University of Southern California Dissertations and Theses

The Geochemical Cycle Of Mercury And The Pollutional Increment

(USC Thesis Other)

The Geochemical Cycle Of Mercury And The Pollutional Increment

PDF

Download a page range

Download transcript

Copy asset link

Request this asset

Transcript (if available)

Content INFORMATION TO USERS
This material was produced from a microfilm copy of the original document. While
th e most advanced technological means to photograph and reproduce this document
have been used, the quality is heavily dependent upon the quality of the original
submitted.
The following explanation of techniques is provided to help you understand
markings or patterns which may appear on this reproduction.
1 .T h e sign o r "target" for pages apparently lacking from the document
photographed is "Missing Page(s)". If it w a s possible to obtain the missing
page(s) or section, they are spliced into the film along with adjacent pages.
T his may have necessitated cutting thru an image and duplicating adjacent
pages to insure you com plete continuity.
2. W hen an image on the film is obliterated with a large round black mark, it
is an indication that the photographer suspected that the copy may have
m oved during exposure and thus cause a blurred image. You will find a
good image of the page in the adjacent frame.
3. W hen a m ap, drawing or chart, etc., was part of the material being
photographed the photographer followed a definite method in
"sectioning" the material. It is customary to begin photoing at the upper
le ft hand corner of a large sheet and to continue photoing from left to
rig h t in equal sections with a small overlap. If necessary, sectioning is
continued again — beginning below the first row and continuing on until
com plete.
4. T h e m ajority of users indicate that the textual content is of greatest value,
however, a somewhat higher quality reproduction could be made from
"photographs" if, essential to the understanding of the dissertation. Silver
prints of "photographs" may be ordered at additional charge by writing
th e Order Department, giving the catalog number, title, author and
specific pages you wish reproduced.
5. PLEASE NOTE: Some pages may have indistinct print. Filmed as
received.
Xerox University Microfilms
300 North Zeeb Road
Ann Arbor, Michigan 48106
J r '
74-28,442
HESS, Frank Devereaux, 1916-
THE GEOCHEMICAL CYCLE OF MERCURY AND THE
POLLUTIONAL INCREMENT.
University of Southern California, Ph.D., 1974
Geochemistry
Xerox University Microfilms , Ann Arbor, Michigan 48106
*
THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED.
THE GEOCHEMICAL CYCLE OF MERCURY
AND
THE POLLUTIONAL INCREMENT
by
Frank Devereaux Hess
A Dissertation Presented to the
FACULTY OF THE GRADUATE SCHOOL
UNIVERSITY OF SOUTHERN CALIFORNIA
In Partial Fulfillment of the
Requirements for the Degree
DOCTOR OF PHILOSOPHY
(Geological Sciences)
August 1974
UNIVERSITY O F SOUTHERN CALIFORNIA
THE GRADUATE SCHOOL
UNIVERSITY PARK
LOS ANGELES. CALIFORNIA S 0 0 0 7
This thesis, written by
Frank..Deyereai^Hess
under the direction of h.j*S...Thesis Committee,
and approved by all its members, has been p re
sented to and accepted by the Dean of The
Graduate School, in partial fulfillment of the
requirements for the degree of
DOCTOR OF PHILOSOPHY
Dean
D ate—
THESIS COMMITTEE
CONTENTS
PAGE
ABSTRACT........................................... vi
I. MERCURY: THE HISTORICAL PERSPECTIVE...... 1
1. The Minamata incident................... 1
2. Purpose of this study................... 3
3. Mercury in foods........................ 4
II. THE GEOCHEMICAL BALANCE OF MERCURY......... 8
1. The balance defined..................... 8
2. Rocks and sediments: Masses........... 10
3. Rocks and sediments: Mercury
distribution............................ 12
4. Calculation of the geochemical
balance.................................. 26
III. THE GEOCHEMICAL CYCLE OF MERCURY........... 28
1. Primary cycle............................ 28
2. The Holocene: General considerations.. 28
3. The pre-agricultural cycle.............. 34
4. The pre-industrial cycle................ 35
5. The modem cycle: General
considerations.......................... 37
IV. THE POLLUTIONAL INCREMENT.......... 43
1. Mercury from industry -
agriculture............................. 43
2. Mercury as a by-product of smelting.... 44
3. Mercury from fossil fuels............... 49
4. Analyses of mercury in coal,
peat, petroleum......................... 52
ii
PAGE
5. Compilation: The pollutional
increment and the modem cycle......... 58
V. OCCURRENCE OF MERCURY IN COAL............... 60
1. Correlation coefficients............... 60
2. Relation of mercury to coalification... 63
VI. STEPS TOWARD MERCURY POLLUTION CONTROL 68
ACKNOWLEDGEMENTS.................................. 75
Appendix 1: Analytical Methods................. 76
Appendix 2: Mercury in coal: Correlation
Coefficients........................ 85
Appendix 3: Proximate Analysis of Coals
and Peats........................... 87
REFERENCES........................................ 89
TABLES
NUMBER TITLE PAGE
1. Mercury content of common foods........ 5
2. Mercury concentrations in museum
specimens of tuna and swordfish
(neutron activation analysis).......... 7
3. Masses of crustal rocks and sedi
ments .................................... 11
4. Mercury contents of rocks and
sediments............................... 17
5. Mercury content of exposed rocks....... 35
6. River burden carried to sea,
world wide.............................. 36
7. Annual transport rate of mercury
during various cycles.................. 38
8. Range of possible mercury discharges
from copper, lead, and zinc smelting.
Calculated from reported mercury
content of predominant ore minerals.... 48
9. Possible mercury discharges from
copper, lead, and zinc smelting.
Calculated from mercury analysis
of predominant ore minerals............ 50
10. Mercury content of fossil fuels........ 53
11. Mercury content of United States
coals, by area.......................... 54
12. World coal production and mercury
content for 1969........................ 55
13. United States coal reserves
as of 1965.............................. 57
14. Mercury entering the environment:
The pollutional increment.............. 58
15. Annual transport rate of mercury,
all cycles.............................. 59
iv
TABLES
NUMBER TITLE PAGE
16. Correlation coefficients for
mercury and other trace elements
in Illinois coals...................... 61
17. Substitution factors for mercury 63
18. Correlation coefficients for minor
and trace elements in Illinois
coals................................... 86
19. Proximate analysis of coals and
peats................................... 88
v
FIGURES
NUMBER TITLE PAGE
1. Mercury concentration in the
food chain............................. 6
2. Mercury content of various rocks 13
3. Formation of sediments from
primary igneous rock.................. 21
4. Flow of mercury in formation
of existing sediments................. 22
5. Distribution of mercury deposits,
world wide............................. 40
6. Metal provinces in western America.... 41
7. Flow of industrial and agricultural
mercury, in tons, United States,
1971.................................... 45
8. Mercury versus volatiles in
peats and coals........................ 65
9. Cycle of materials in and waste
products out of a power plant.......... 71
10. Mercury in USGS G-l granite as
analyzed over a five year period. 78
11. Diagram of analytical method for
mercury by neutron activation........ 80
vi
ABSTRACT
Recent occurrences of mass poisoning by mercury, in
troduced into food sources as a pollutant, raised two im
portant questions - what is the natural level of Hg in the
environment, and how far has pollution raised that level?
Seeking to answer these questions, this study was under
taken, first to determine a static geochemical balance for
Hg, then to determine the geochemical cycle - the flux of
Hg through the environment in terms of tons per year, before
and after pollutional conditions existed. The geochemical
balance, the total Hg mobilized from weathered igneous rock
Q
and mantle sources and deposited in sediments, is 66 x 10
T Hg from weathered igneous rock and 104 x 10^ T Hg to se
diments, the difference of 38 x 10^ T being derived from
the mantle at sites of sea-floor spreading, and from igne
ous rocks as volcanic gases and hydrothermal solutions.
From this balance the primary geochemical cycle (annual Hg
flux) is computed at 100 T yr“^, not including recycled ma
terial. Three subsequent cycles are then distinguished:
(1) a pre-agricultural cycle of 600 T yr"^, (2) a pre-in
dustrial cycle at 1500 T yr”^ for Hg deposited in marine
sediments, (3) a modern cycle, which is the previous natur
al cycle plus a pollutional increment, making 30,000 T yr"^-
in all - 20,000 T natural, 6500 T from industry, 1200 T
from base-metal smelting, and 1400 T from fossil-fuel com
bustion. Analysis of fossil fuels gave 80 to 340 ppb Hg
in U. S. coals, 100 to 180 ppb Hg in German coals, 70 and
vSii
100 ppb Hg in U. S. petroleums. Further studies showed
that Hg in coal correlates with other chalcophile trace me
tals, but not with elements in clay minerals, and that the
Hg content of coals is inversely proportional to the degree
of coalification as expressed by percent volatiles, indica
ting loss of Hg as coalification progresses. The impact
of SO^ scrubbers for coal-fired power plants on trace-
met al removal was considered, since such systems, which may
soon be adopted on a large scale, may be useful to remove
Hg from stack gases.
viii
CHAPTER I
MERCURY: THE HISTORICAL PERSPECTIVE
Land, labor, and capital have their
prices. But environmental resources -
public watercourses, the atmosphere,
and public lands - have no price be
cause no one owns them. As a result,
these resources are treated as free
goods. When scarce resources are
made available at a zero price, and
with no market control of their use,
they are overcrowded and abused.
Freeman
1. The Minamata incident.
In 1953 Dr. Hosokawa, physician in the prefecture of
Minamata, Kyushu, Japan, noticed an unusual illness among
villagers living on Minamata Bay, bordering the East China
Sea. First they felt numbness in the skin of the hands
and forearms, in lips and tongue, leading to slurring of
speech, and followed by unsteady gait, loss of muscular
control and peripheral vision. Up to 1972, 128 cases were
treated, most patients either dying or suffering serious
permanent disability (D'ltri, 1972).
When in 1956 the Minamata disease was at its height,
it was noted that fishermen and their families were the
principal victims, and a high fish diet seemed to be com
mon to all those who had the strange nervous disorder.
Fishing in the bay was prohibited. The effect was an
immediate decline in the number of new cases of Minamata
disease.
As the malady attracted the attention of medical in
vestigators, one of their number (Takeuchi, 1957) was re
minded of an article he had read about the illness of four
British workers in a seed-dressing factory. These men were
handling a fungicide used to preserve the seeds during
storage and planting - its base, a methyl mercury compound.
They also showed the skin numbness, the deterioration of
speech and vision, the poor muscular control. With this
information at hand, Dr. Takeuchi had mercury analyses run
on liver, brain, and kidney tissues from 17 victims of the
Minamata disease. Their Hg content was nearly 30 times
higher than that of controls.
Minamata Bay, on the southwest coast of Kyushu, is
2
about 8 km in area and 85% landlocked, with minimal cir
culation of water from the East China Sea. On its north
side stood a factory making acetaldehyde, plastics, and
fertilizers. It discharged an effluent directly into the
bay until 1957 or 1958; then, as attention was called to
the hazard of the Hg content, diverted it to the Minamata
River and the larger and more open Shiranuhi Sea. In 1959
Minamata disease made its appearance among the dwellers
along the lower course of the Minamata River.
A recurrent theme among sufferers from the disease
was their dependence on fish, particularly shellfish, as a
major item of diet. A study by Irukayama (1961) led him to
conclude that highly toxic methylmercury chloride in wastes
from the acetaldehyde plant was concentrated in the marine
2
life of the bay, and passed on to the terminal members of
the food chain - the fishermen. Mercury, therefore, joins
the list of poisons that occur at very low concentrations
in practically all natural materials, but at times accumu
late to toxic levels in foodstuffs. When this happens,
the suspicion arises that some contributory source has
greatly augmented the supply of the toxin in question, and
nowadays the most likely variable source is human activity.
2. Purpose of this study.
This work is addressed to the question of the natural
balance, or geochemical cycle, of mercury, and the extent
to which the cycle has been perturbed by man. The sources
from which mercury enters the environment will be examined:
first, the natural background produced by erosion, trans
port, and deposition as alluvium and bottom sediments, and
then the superimposed mercury content in effluvia from
man's activities - the pollutional increment. The latter
will be discussed in terms of contributions from: (1) in
dustrial-agricultural sources, and (2) smelting-fuel com
bustion sources. In recognition of the seriousness of
mercury pollution by fuel combustion, this aspect of the
overall problem of pollution was selected as the principal
contribution of the present work in the form of original
data.
It will be noted that emphasis is given to the total
flux of mercury in all forms (whether or not biologically
available or hazardous) through the environment. Except
3
for the brief discussion in the next section, no study was
attempted of mercury concentrations in foods. Moreover,
although distinctions between inorganic and metal-organic
forms of mercury are considered, no attempt has been made
to quantify them, such quantification comprising a major
effort in itself.
3. Mercury in foods.
Considering once more the Minamata incident, the
toxic agent in the industrial waste was a methyl mercury
derivative, which comprised 1% of the spent acetaldehyde
catalysts, mercuric sulfate and chloride, discharged into
the bay (Wood, 1968). Mercury compounds vary widely in
their toxicity, and Hg vapor itself is toxic, the American
Conference of Government and Industrial Hygienists recom
mending threshold limit values (continuous exposure) of
0.1 mg m“3 for metallic and inorganic Hg in air, and 0.01
mg nf3 for organic Hg (Truhaut, 1969). As Truhaut's sur
vey noted, while the aryl compound, phenyl Hg, converts to
a readily eliminated inorganic form, its homologue methyl
Hg is more stable, having a half-life in man of 70 days.
The central nervous system is most susceptible to this
form; 98% of the Hg in the brain is the methyl compound,
and it can pass through the placenta to cause mental retar
dation, cerebral palsy, convulsions and death in the new
born. Twenty-two of the Minamata victims were infants.
From our food and water, we take up an average of 20
g of Hg per day; from the air we breathe, another 0.11 g
(Schroeder, 1971). This much is tolerable; it may even be
beneficial. As expressed by Goldwater (1971), "Tolerance
for a potent substance not infrequently grows into depen
dence on it, and it is reasonable to suppose that man, as
well as other forms of life, may now be dependent on mer
cury as a useful trace element." Or from Magee (1973),
"... it is no accident that the level of metabolic toler
ance in many cases is close to average crustal abundance,
the amount of the element found in ordinary dirt." Poi
soning occurs only when levels of Hg normally present in
the environment are locally exceeded by several fold,
usually as a result of sustained pollution, and frequently
aggravated by concentration in the food chain.
A table by Tanner (1972) shows Hg contents of common
foodstuffs used in the United States at the present time:
TABLE 1
Mercury Content of Common Foods
Hg, ppb
(parts per billion) Hg, ppb
Range Median Range
Median
Flour <3-6 <3 <2-7 3
Milk, dry <4-27 10 <1-7 3
Milk, whole <1-9 <1 5-43 14
Sugar <3-10 <3 <2-8 3
Potatoes <1-15 3 <2-5 <2
The authors conclude that with the exception of cer
tain fish, the major foods in this country are essentially
5
free of Hg. There is little cause for complacency in the
situation, as a few years' mismanagement of Hg-base fungi
cides, for example, could lead to high Hg levels for a
given region or a given crop. An illustration given by
Storrs (1970) is that of three members of an Alamogordo,
New Mexico, family hospitalized after eating pork which
had fed on grain treated with a methyl Hg preservative.
The Hg content of the pork was 27.5 ppm, about lO^- times
that of the beef noted in Table 1.
Probably as a result of the Minamata experience, no
occurrence of Hg in food has been followed more closely
than that of fish and shellfish. Because of its tendency
to accumulate in fatty tissue, it concentrates in the food
chain ascending from the simpler marine organisms to the
predators. This is shown in Figure 1, modified from
Birke (1972):
FIGURE 1
Mercury Concentration in the Food Chain
Approximate
Hg level, ppb
10,000 _________
1,000 __________ k////Mil///. //A fish eaters
i00 ___________I ! //////////////) P^e, perch
10
1
0.1 ______
0.01 [7777777777777771 water
The substantially higher level of Hg in seafood was
noted forty years ago by Stock (1934), whose analyses of Hg
in fish ranged from 28 to 180 ppb, and in shellfish from 24
to 82 ppb. It does not appear, however, that the high
levels can be uncritically ascribed to the activities of
man. High Hg levels occur in Pacific tuna today, but they
are equally high in museum specimens dating back nearly a
hundred years. Miller (1972) reported analyses as follows:
TABLE 2
Mercury Concentrations in Museum Specimens
of Tuna and Swordfish (Neutron Activation Analysis)
Hg, ppm
7 Tuna (1878-1909), average 0.95 + 0.33
Swordfish (1946) 1.36 + 0.31
5 Tuna, recent, average 0.91 + 0.47
6 Swordfish, recent, average 3.1 +1.5
It is evident that the relation between Hg as natural
product and as pollutant to that found in foodstuffs is on
ly beginning to be explored. For the first time in history
we are about to undertake large-scale regulatory measures
in the name of a habitable environment. These measures
will restrict activities that we are accustomed to exercise
without restraint - particularly the exploitation of the
environment for economic ends. They will call for impar
tial decisions, based on the most reliable information that
we can arrive at. Some of that information is compiled in
the remaining sections of this work.
CHAPTER II
THE GEOCHEMICAL BALANCE OF MERCURY
A thing therefore never returns to
nothing, but all things after dis
ruption go back into the first bodies
of matter.
Lucretius
1. The balance defined.
The concept of a geochemical cycle was foreseen by
Hailey, who noted in the eighteenth century that the age
of the seas could be determined if an appreciable increase
could be found in the salt content since ancient times
(Livingstone, 1963). The formulation of a balance was gi
ven by Mead (1914) and is essentially unchanged today; this
is the postulate that the mass of igneous rocks that have
weathered to form existing sediments, sedimentary rocks,
and the dissolved species derived from them, can be esti
mated by comparing their elemental composition:
x granite + y basalt = a shale + b sandstone +
c limestone
Here the lower-case letters stand for the content of a
given element in each type of rock, a content obtained by
averaging as many reliable analyses as can be obtained,
weighting them if necessary to adjust for the proportion
ate part of the rock type that they represent.
The equation is usually solved for the term that
cannot be measured directly, i.e., the mass of the weather
ed igneous rock. But if equations for several elements are
set up simultaneously, then other rock masses may be com
puted. Goldschmidt (1954), whose work on the geochemical
balance may be called definitive, used three simultaneous
equations for Na, Ca, and Mg. Reversing this procedure,
Horn (1966) , using a computer method with rock masses as
the input, determined the composition of the various rocks
and sediments for no less than 65 elements.
Other important contributions to the concept of geo
chemical balance (static model, outlined above) and geo
chemical cycle (dynamic model, based on rates of transport
of eroded materials) were made by Kuenen (1941), Conway
(1942), Wickman (1954), Poldervaart (1955), Turkenian
(1961) , and Barth (1962) , and will be referred to as they
are utilized in this discussion.
The limitations on our knowledge of the factors en
tering into the geochemical balance require that certain
assumptions be made. These are justifiable, as a rule,
when the elements concerned are stable over a wide temper
ature range, and their transport paths are uncomplicated.
They must be scrutinized carefully, however, in dealing
with such elements as Hg and As. The geochemical balance,
we will show, discriminates between Hg transported to sedi
ments by the weathering-erosion-deposition cycle and that
transported as vapor, volcanic exhalations, and hydrother
mal solutions. But it does not make a distinction between
sources of Hg in the latter case - whether from the mantle,
from primary igneous rock, ancient weathered sediments, or
9
secondary igneous rock. To some degree, therefore, the
concept of a balance, developed to determine the igneous-
rock equivalent of existing sediment and sedimentary rocks
(hereafter referred to jointly as sediments), is an over
simplification when applied to the determination of the
natural Hg flux.
Another assumption concerns the relative proportions
of primary and secondary igneous rocks which have contri
buted to existing sediments. The proportions are usually
assumed (see, for example, Onishi, 1955) to be those which
exist today, but obviously a large part of existing sedi
ments were formed when the proportion of secondary igneous
rock was lower than it is today. In this work a correction
is made for the larger share of primary igneous rock exis
ting at the time the average sediments were deposited.
2. Rocks and sediments: Masses.
Early studies of the geochemical balance were based
on the familiar rock types: igneous, metamorphic, lime
stone, sandstone, and shale. But a balance can be based
on any system of related units showing a sufficient degree
of homogeneity; Green's (1972) classifications may be con
sulted for examples. Today most determinations of geochem
ical balance follow the system of Poldervaart (1955) , who
classified the rocks and sediment of the lithosphere into
four broad structural provinces and several petrological
subprovinces, giving them masses shown in Table 3. Ton
nages are metric unless otherwise noted. 10
TABLE 3
Masses
Deep oceanic
Suboceanic
Continental
shield
Y >ung folded
belts
of Crustal Rocks and Sediments
1015 T
Pelagic sediment
Calcareous sands and ooze 156
Red clay 42
Siliceous ooze 19
Subtotal 217
Hemipelagic sediment
Terrigenous mud 505
Coral mud 150
Volcanic mud 25
Shelf sediment, listed by
source rock (proportions
same as young folded belts)
Shale 168
Sandstone 42
Limestone 71
Graywacke 16
Andesite 19
Rhyolite __6
Subtotal 1005
Shale 57
Sandstone 60
Limestone 22
Subtotal 140
Shale 177
Sandstone 44
Limestone 75
Graywacke 17
Andesite 20
Rhyolite __7
Subtotal 340
(After Poldervaart, 1955)
11
3. Rocks and sediments: Mercury distribution.
The range in composition of major constituents in a
given rock type is relatively small, since the type is de
fined by its major minerals (plus textural features), which
in turn are fixed by their chemical constituents. For this
reason, geochemical balances based on major constituents
should not show gross disagreement, and in fact the prin
cipal area of disagreement is in the selection of rock
domains, thicknesses, and masses.
With minor and trace elements, however, there is a
great deal of uncertainty observed in analyses of a given
host rock, when such analyses are compiled from the liter
ature. The reasons are twofold: the first reason being
the difficulty of obtaining precise analyses in the parts-
per-billion range, and is discussed in Appendix A, Analy
tical Methods. The second reason is inherent in the na
ture of the material; i.e., while there are broad affini
ties of some rock types for a trace metal based on its
geochemical affinity (lithophile, chalcophile, siderophile),
or on its ready substitution for a major cation by reason
of compatibility of ionic radius and charge, yet the con
tent of trace metal in a particular specimen of rock has
been determined largely by its availability during and
after the rock-forming process. The availability, as will
be shown, varies greatly with locality, especially for Hg,
due to its mobility. Consequently there exists a wide
range in the trace metal content of rocks. Figure 2,
Sedi- Meta- Igneous
mentary morphic
FIGURE 2
Mercury Content of Various Rocks
T
Basic Extrusive: Basalts
--------- Basic Intrusive: Gabbro, Diabase
Intermediate Intrusive
+
+
Carbonaceous Shale
Interm ediate Extrusive
Acidic Extrusive: Rhyolite, Trachyte
Acidic^ Intrusive: Granite, Granodiorite, Dacite
-----------1 ------------- — Alkalic: Nepheline Syenite,
Syenite, Phonolite
Marble, Marbleized Dolomite
Gneiss
Amphibolite
Quartzite
Schist
+
Hornfels
Limestone, Dolomite
— Sandstone, Arkose, Conglomerate
— Shale, Mudstone, Argillite I
-----------------Recent Stream , Lake Sediments
-+ '-T------- I _________
10 .
From Jon asson (1972)
100
Mercury, ppb
1000 10,000
based on a compilation from many sources made by Jonasson
(1972) , shows the means and ranges for Hg in the rock types
that are used to compute the geochemical balance. The
spread for some materials is over two orders of magnitude.
Furthermore, the meap can be appreciably biased by two fac
tors; the first is the relatively small number of accurate
Hg analyses that have been made for some rocks, the second
is the tendency to investigate atypical rocks, more intri
guing to the investigator than typical ones. This may re
sult in analyses that deviate widely from the mean.
As mentioned earlier, some uncertainty is introduced
in the computation of a geochemical balance for Hg by the
difficulty of evaluating mantle contributions (and losses
to the mantle by subduction) as compared to volcanic ema
nations from secondary sources. The factor of a mantle
contribution to the geochemical balance was unknown or ig
nored prior to Barth’s (1962) work; Poldervaart, for exam
ple, found it a problem to explain why the thickness and
deposition rates of pelagic sediment indicated that it had
all been laid down in the last 200 million years. To
quote Barth:
In addition, to the cyclic migration,
we must not forget, however, the new
supply brought in from below... A
small fraction of some of the metals,
for example mercury and perhaps
sodium, are likewise possible products
of degassing and are eventually brought
into the external geochemical cycle
mainly by hydrothermal processes...
The mantle contribution also appears to have affected
14
the results obtained by Onishi (1955) in his computation of
the balance for As, and he was obliged to include an As
contribution from magmatic sources.
Evidence of a possible mantle contribution of Hg may
be noted by comparing the analyses of USGS DTS-1 dunite,
8 ppb Hg (Fleischer, 1970), and of kimberlite, 210 ppb
(this work). If the former can be considered representa
tive of the lower-crust conditions, it may indicate a low
Hg content in the upper mantle. Kimberlite, however, is
also deep-seated in origin. The most likely explanation
for its relatively large Hg content is that it has been
exposed to volcanic emanations, which have been found to
contain appreciable amounts of Hg (Eshleman, 1971).
Other observations based on Figure 2 are:
1. Except for the anomalous Hg content of kimber
lite, there is a general increase in Hg level of
igneous rocks from the ultrabasic through the
acidic members of the series. This increase
would not appear to relate to Si02 content, how
ever, since the alkalic types are highest of all
in Hg.
2. In the metamorphic series, hornfels is presumed
to be beneficiated by hydrothermal Hg or Hg va
por from the plutonic body producing the contact
metamorphism.
3. In the sedimentary series, carbonaceous shale is
anomalously high in Hg. This may indicate either
15
that uptake and concentration by plants has oc
curred, or that concentration of Hg has taken
place after deposition of shale-forming sediment.
Using Figure 2 as a basis and borrowing from other
sources as noted, it is possible to assign Hg values to the
various rocks and sediments listed in Table 3, and to the
igneous rocks whose weathering produced the sediments.
These values are shown in Table 4.
The selection of Hg values appearing in Table 4 is
discussed here:
1. The value of 95 ppb for the calcareous sand and
ooze component of pelagic sediment is averaged
from Aidin1yan's (1963) analyses of foramini-
feral ooze from the Atlantic, Pacific, and
Indian Oceans, weighted for ocean area.
2. The figure of 83 ppb for the red clay portion of
pelagic sediment is averaged from Marowsky's
(1971) figures for Atlantic and Pacific pelagic
clays, weighted for ocean area.
3. The figure of 60 ppb for the siliceous ooze in
the pelagic sediment is the ’’ recent" sandstone
value plus a small increment to allow for organic
Hg uptake.
4. The figure of 60 ppb for terrigenous mud in hemi-
pelagic sediment is taken from the weighted
average for shelf sediment, following Polder-
vaart1 s reasoning that the principal source of
TABLE 4
Mercury Contents of Rocks and Sediments
Material Hg, ppb
Pelagic sediment
Calcareous sand and ooze 95
Red clay 83
Siliceous ooze 60
Hemipelagic sediment
Terrigenous mud 60
Coral mud 45
Volcanic mud 40
Shelf sediment (by source rock)
Shale 67
Sandstone 55
Limestone 40
Graywacke 55
Andesite 66
Rhyolite 62
Sediments of continental shield
and young folded belts Same as shelf
sediment
Basalt 20
Granodiorite 62
Diorite 34
Sea water (dissolved and 0.013
particulate)
shelf sediment is the higher mountain (young
folded belt) areas.
The value for coral mud in hemipelagic sediment,
45 ppb, is derived from the figure for limestone
with an increment to allow for organic uptake.
For the small quantity of hemipelagic sediment
as volcanic mud, no reliable figure is available.
The value of 40 ppb is an average for basic and
acidic extrusive igneous rocks.
For the quantity of sea water, Sverdrup's (1943)
figure of 1370 x 10^ km3 is used, converted to
1400 x 1013 T, while Leatherland's (1971) Hg
analyses for the North Atlantic, averaging 0.013
ppb, is chosen for sea water. The latter in
cludes Hg present in suspended particulates as
well as in solution.
To determine the Hg content of the biosphere, we
use 361 x 10^ km^ as the area of the oceans and
147 x 10^ km^ as that of the land (Sverdrup,
1943). Skirrow (1955) gives 0.002 g cm^ as the
mass per unit area of carbon in marine biota and
0.06 g cm^ in land biota, the total (dry) weight
being about twice the C content (Poldervaart,
1955). Applying Jonasson's (1972) figures of 37
ppb Hg in marine and 40 ppb in land organisms, we
obtain 533 T Hg in the marine biomass and 7056 T
in the land biomass. The biosphere then contains
18
about 8000 T of Hg, an appreciable figure when
calculating an annual Hg budget, but negligible
when compared to other terms in the geochemical
balance.
Atmospheric measurements of Hg over populous land
areas often reflect a pollutional rather than a
natural Hg content. Williston's (1968) finding
of 0.6 to 0.7 nanograms per cubic meter, sampled
at 10,000 feet over the Pacific Ocean, 20 miles
offshore, is probably the closest that we can
approximate an unpolluted atmosphere. It is an
order of magnitude less than the Hg in the air
over the adjacent California coast, which in
places is a pollutional contribution. The den
sity of the atmosphere at 3 km altitude (just
under 10,000 feet) is 0.9094 kg m"^, (List,
1958) giving 0.7 ng kg-^ as the Hg content per
unit mass of air. The total mass of the tropo
sphere is 5100 x 1015 kg (Rankama, 1950) , which
therefore has a total Hg content of 3.6 x 10^ T.
While this is by no means insignificant in terms
of the annual Hg flux, it has no effect on the
geochemical balance. The higher atmosphere
should be relatively free of Hg.
The Hg mass of 3.6 x 10^ T derived here, it
may be noted, is one-third the figure of 10^ T
estimated by Kothny (1973), which was obtained by
assuming an atmospheric mean of 2 ng m"^, i.e.,
three times the value used in our estimate, and
including pollutional Hg.
From these considerations, no further accounting is
made in the geochemical balance for the biosphere and the
atmosphere.
The last figures required for the geochemical bal
ance are those for masses of weathered primary and secon
dary igneous rock. For total igneous rock, Horn's (1966)
value of 2040 x 10^** T is used here because, like this
work, it is based on Poldervaart1s classification.
Existing or surviving sediments (the terms are used
interchangeably) have their ultimate source in primordial
or primary igneous rock. Some sediments were formed by
direct weathering-erosion-deposition of this primary rock,
however, large masses of existing sediments were laid down
by weathering of older sediments, and still others origina
ted in the burial and recrystallization of ancient sedi
ments, forming secondary igneous rocks which in turn wea
thered and deposited their debris as sediments. Various
permutations of these processes may have occurred, but a
simplified diagram would be:
20
FIGURE 3
Formation of Sediments from Primary Igneous Rock
M
(a)
PI
M
ES
M
(b)
AS
M
AS
M,
SI
(c)
Mpj = mass of primary igneous rock
M = mass of secondary igneous rock
D 1
M^s = mass of ancient sediments, no longer
surviving
Mgs = mass of existing sediments
(1) MpjCa) + Mpj (b) + MgI = Mti
M r j , ] - = mass of total weathered igneous rock
In tracing the path of Hg from primary igneous rock
to existing sediments, it is seen that paths (a) and (b)
can be considered as one, provided that no Hg loss occurs
in the transition from M^g to Mgg. Path (c) , however, may
yield sediments with a different Hg content from those
formed by (a) or (b), due to losses by outgassing. The
Hg flow itself may be diagrammed as in Figure 4.
Wavy lines indicate transport of Hg from the source
rock in a hydrothermal or vapor phase, i.e., no weathering
of source rock has occurred, and the sediment is enriched
FIGURE 4
Flow of Mercury in Formation of Existing Sediments
(f)
HgPI =
Hg
SI
Hg
'AS
Hg
ES
H%
Hg from primary igneous rock
Hg from secondary igneous rock
Hg from ancient sediments, no longer
surviving
Hg in existing sediments
Hg from mantle
in Hg from a remote source, with deposition of Hg often
localized as an ore body. As with the rock masses of Fi
gure 3, paths (b) , (c) , and (d) may be treated as one,
since they represent only a weathering-erosion-deposition
process, however permutated. Paths (a), (e) and (f) are
also effectively one, if it is assumed that the igneous
rocks which lose Hg by outgassing are deepseated plutons,
not represented in the Table 4 analyses of Hg rock types.
Figures 3 and 4 may then be made the basis for a geochemi-
22
cal balance having these terms on the left (source) side:
1. Hg from weathered primary igneous rock
2. Hg from weathered secondary igneous rock
3. Hg from all deep-seated sources, mobilized by
heat and transported as vapor or hydrothermal
solution. It also includes a process of par
tial chemical weathering which may be of impor
tance - the leaching of oceanic basalts at sites
of sea-floor spreading. This path was described
by Corliss (1971) in considering a mantle source
for Mn, Fe, Co, and rare-earth elements found in
Mid-Atlantic Ridge basalts:
It is suggested that these components...
are mobilized by dissolution as chloride
complexes in sea water... These solu
tions may be the metal bearing 'hydro-
thermal exhalations' or 'volcanic emana
tions ' that accompany submarine volcanism.
According to this concent, Hg is added to sea water
either as gaseous emanations accompanying eruptive volcan
ism, or leached from freshly extruded rocks along the
oceanic ridges and rises, to be scavenged by particulate
matter (perhaps organic in part) and redeposited on the
sea floor. Evidence for this deposition is found in
fl
Bostrom's (1969) finding of 400 ppb Hg in the crest of the
East Pacific Rise, compared to 1 - 2 ppb for locations off
the rise.
While initially all sediments had to originate from
primary igneous rock, today they are formed from the two
sources, primary and secondary rocks, in the proportions
in which they are exposed. (Formation from other sedimen
tary rocks need not be considered here, because we wish to
determine only the extent to which igneous rocks have con
tributed to existing sediments.) Assuming that erosional
processes and survival rates have been fairly constant
throughout erosional history, surviving sediments should
have a composition corresponding, not to the average pro
portions of primary and secondary igneous rocks existing
today, as is frequently assumed in setting up geochemical
balances, nor yet to the average proportions of these rocks
existing throughout erosional history. Rather, they should
have an amount of secondary igneous rock corresponding to
about two-thirds of its present proportionate amount.
This is the ratio that existed when the quantity of sur
viving sediments attained half its present mass: i.e.,
plotting the mass of surviving sediments as a first-order
function of time, it is the locus in time of the center of
mass, or a point in time two-thirds of the way between
the start of erosional history and the present.
The mass of primary igneous rock contributing to
the sediments, of course, is simply the difference between
the total igneous rock and the secondary igneous contri
bution .
The present proportions of crustal igneous rock,
according to Poldervaart (1955), is 41 parts granodiorite,
10 parts diorite, and 49 parts olivine and tholeiite ba-
24
salt. These figures provide a ratio of very nearly 1 to 1
for primary and secondary igneous rocks existing today, on
the assumption that basalts are primary, granodiorite and
diorite are secondary. But since we wish to reduce the
proportion of the secondary rock to two-thirds of its pre
sent value, the ratio used in the geochemical equation is:
(2) 1 1/3 primary igneous +2/3 secondary igneous
= total igneous rock eroded to form sediments.
In calculating its Hg content, the tonnage of secondary
igneous rock will be further distributed between granodio
rite and diorite according to Poldervaart's estimate.
Using Horn's calculation of 2040 x 10^ T for total
weathered igneous rock, the tonnages for Mpj and Mg^ are
obtained by solving the equations:
(3) M'pi = 1
(4) M f + M'SI = 2040 x 1015
(5) M'gi = 1020 x 1015
(6) MSI = fxM'sx = § (1020 x 1015)
(7) MSI = 680 x 1015
(8) HpI = Hpj - MgI = 2040 x 1015 - 680 x 1015
(9) Mpx = 1360 x 1015
The primes in the above equations represent present
masses of primary and secondary igneous rocks, from the
relations derived by Poldervaart for basalt and (grano
diorite + diorite) . The rock masses of (7) and (9) are
those that existed when the average surviving sediments
were laid down.
4. Calculation of the geochemical balance.
The equation for the geochemical balance, in com
plete form, would be:
(10> CPIMPI + CSIMSI + v “ scsMs + Vsw
-I- C i p M i p "I" C g M g
Cpj = concentration of Hg in weathered primary
igneous rock
Mpi = mass, weathered primary igneous rock
Csx = concentration of Hg in weathered secondary
igneous rock
Mgj = mass, weathered secondary igneous rock
V = mass (following Conway’s notation, 1942) of
Hg from sources other than rock weathering
and erosion, i.e., mantle and volcano contri
butions
Cg = concentration of Hg in sediments (sediment
and sedimentary rocks)
Mg = mass, sediments
C^ = concentration of Hg in troposphere
M = mass, troposphere
T
C = concentration of Hg in biosphere
B
M = mass, biosphere
B
The last two terms in (10) are omitted as negligible
in the final computation of the Hg balance.
Equation (10) may now be solved by multiplying the
figures for mass of each type of rock or sediment (Table 2,
26
plus equations' C7J and 191) by Hg content of the same ma
terial (Table 4) .
(11) 27.2 x 109 + 38.8 x 109 + Y = 104.4 x 109 + 0.02 x 109
(12) 66.0 x 109 + Y = 104.4 x 109
(13) Y = 38.4 x 109
The solution to the equation for the geochemical
balance, therefore, requires that 37% of all Hg in sedi
ment and sedimentary rocks be supplied to the host material
as a contribution from remote sources - mantle emanations,
volcanic gases, hydrothermal solutions, or sea-water
leachings at sea-floor spreading sites.
This percentage may be compared to that derived for
another element forming volatile compounds - arsenic.
Onishi (1955) found the As in sediments to be 1.32 g c m ” 2
of the earth's surface area, while weathered igneous
rocks, by his calculations, contributed only 0.32 g c m “ 2.
The difference of 607o he attributed to direct release of
As from magmatic sources.
27
CHAPTER III
THE GEOCHEMICAL CYCLE OF MERCURY
1. Primary cycle.
The total quantity of 104.4 x 109 T of Hg mobilized
to form existing sediments is not of particularly heuris
tic interest. A more useful figure would be the rate at
which Hg has been mobilized and cycled through the environ
ment, for this could be used as the background against
which we could compare the yearly increment added by
pollution. A minimum can be estimated for this yearly
rate by dividing the number of years that deposition of
9
sediments has occurred (roughly 10 years, Erikkson,
1960) into the Hg tonnage of the sediments.
(14) Hg, T yr"1 = 4 x 1q9
109
(15) Hg, T yr-1 = IQ4.4 T yr-1
In view of the uncertainties involved, a rounded fi
gure of 100 T yr“l is proposed for the natural Hg flux
contributing to existing sediments. This will be referred
to as the primary cycle of Hg.
2. The Holocene: General considerations.
The Hg flux designated the primary cycle is quite
different from the total Hg flux through the environment,
being the rate at which fresh contributions of Hg would
have to be added to sediments to bring them up to their
present levels. The actual flux of Hg through the environ
ment includes much recycling or reworking of previously
introduced material. Therefore, the annual Hg flux that
we would measure as a rate process is n (100) T yr“^,
where n is the average number of times recycling of sedi
ments has occurred. Such a measurement is no longer possi
ble over the whole period of erosional history. In the
first place erosion rates have increased several fold in
the last few thousand years as a result of man's activi
ties - clearing forests for grazing and crop land, and re
placing these in turn with housing developments (Douglas,
1967; Meade, 1969). Likewise, if mountain building is
episodic, present erosion rates may not reflect accurately
those of the past.
To take these factors into account, we compute a
second cycle for Hg, based on erosion rates rather than
overall erosion. This is the cycle that prevailed during
the early part of the Holocene, after our climate acquired
its present pattern, until a period, perhaps 3000 years
ago, when agriculture and grazing began to produce the
erosion rates we see today. This will be termed the pre-
agricultural cycle.
Using this early Holocene cycle as a starting point,
we proceed to determine, or at least roughly estimate,
the Hg flux that existed for a brief period, about a
hundred years ago when agriculture was practiced on a
world-wide scale, but industrial uses of Hg had not pro
liferated to the extent of comprising a serious pollution-
al problem. This third cycle is the pre-industrial cycle,
and is the one of immediate concern for comparing today's
input of Hg to the environment.
We shall conclude, then, with a fourth cycle, the
modern cycle, which is the pre-industrial cycle plus the
pollutional increment. This is the flux that we would
measure when we sample today's soils, rivers, seas, and
atmosphere - all media by which transport of Hg might
occur.
In summarized form the four cycles are:
Cycle
Primary
2. Pre-agricultural
Description
Hg flux through the terres
trial and marine environments
resulting from the weather
ing of freshly exposed igneous
rock, leaching of rocks at
sites of sea-floor spreading,
and vulcanism. Based on esti
mates of masses and Hg content
of eroded igneous rock and
resulting sediments and sedi
mentary rocks. Excludes re
cycling .
Hg flux during the period
10,000 - 3,000 years ago,
establishing a base level con
sidered tolerable by life.
30
3. Pre-industrial
4. Modern
Estimated from Hg content of
surficial rocks, and from ero
sion rates as determined by
chemical weathering and sedi
ment deposition rates. It is
limited, therefore, to Hg
carried out to sea, and does
not include Hg mobilized by
weathering and erosion but
deposited with alluvium with
in continental borders.
Hg flux as of a hundred years
ago (no sharp time demarca
tion can be assigned) when
land under cultivation and
deforested areas approximated
their present extent. Esti
mated from Hg content of sur
ficial rocks and erosion
rates as determined by pre
sent-day river burdens. This
flux establishes the pre-pol-
lutional level, and ideally
would be the one that would
exist with completely effec
tive Hg pollution controls.
The pre-industrial level plus
31
pollutional increments from
two major sources: the mining
of Hg for use as an ingredient
in chemicals for industry,
medicine, and agriculture,
and the venting of Hg to the
atmosphere as a byproduct of
the smelting of base metals
and the combustion of fossil
fuels.
Since we are a part of and directly affected by all
aspects of our terrestrial environment, we are concerned
with all Hg that is mobilized, and not merely that portion
which is carried out to sea. Items 3 and 4 should there
fore be estimated in terms of the total river burden
dropped in alluvial valleys as well as that which is borne
out to sea. The figures available for an estimate amount
to little more than guesses, although a firm estimate has
been made for the Potomac River (95% terrestrial alluvium,
5% detrital discharge to sea, Meade, 1969). Such estima
tes obviously do not apply to the pre-agricultural cycle,
since river burdens were so much lower than today's that
rivers were better graded; having no dams, they were free
to scour their flood-plains occasionally and carry a larger
proportion of their burden to sea.
If we view Hg as an undesirable migrant through our
environment, the form in which it occurs is of interest
32
as well as its absolute quantity. Dissolved Hg (probably
Hg°, Hem, 1970) is removed from solution by sorption on
suspended particulates and bottom sediments. The Salinas
River of West Central California may be cited as an example.
Draining an area adjacent to the mercuriferous Franciscan
Formation of the California Coastal Range, its head waters
were found to contain 12 ppb Hg, its mouth only 5 ppb.
(Dilution by low-Hg tributaries is, of course, a possibi
lity.) Similar instances of Hg depletion of river waters
are reported by Dall'Aglio (1968), Smith (1971) , and
Cranston (1972). In the words of Jenne (1971):
...mercury appears to be strongly sorbed
by soils and sediments. Mercury must be
fixed, that is, be desorbed very slowly,
by soils and fluvial sediments... In
asmuch as mercury forms many stable organo-
metallic compounds... probably a very sig
nificant part of the cationic mercury
that has resided in natural fresh waters
for times on the order of hours to days
will be in some organic form... The
sorption efficiency ascribed to clays...
is very likely due to the nearly ubi
quitous microcrystalline iron and to a
lesser extent, manganese oxide coatings
present on the clays...
The consequence is that much Hg, initially in solu
tion, becomes fixed on clays and other particulates, and
can be filtered from domestic water supplies before use.
Its immobilization, however, is precarious; in bottom
sediments under anaerobic conditions it may be converted
to the toxic methyl mercury by reaction with methane from
methanogenic bacteria (Wood, 1968).
33
3. The pre-agricultural cycle.
We may proceed to derive the Hg flux for Item 2, the . v
pre-agricultural cycle. The input figures - river runoff,
dissolved and suspended solids, and associated erosion
rates are found in Livingstone (1963), Holeman (1968), Jud-
son (1968), Moore (1969), Gregor (1970), Hood (1971), and
Gibbs (1972), and these authors will be cited when appro
priate.
Considering that chemical weathering is little influ
enced by man, Gregor calculated that the Na content' of mo
dern rivers indicated a continental denudation rate of
10 x 10^ T yr-- * - . While this derivation is more likely to
represent an upper limit, it agrees well enough with his
9 1
figure of 11 x 10 T yr from sediment survival rates, and
with Judson's of 9 x 10^ T yr"-*- from sediment deposition
rates, to permit averaging the three, giving 10 x 10^ Tyr"-*-
as the rate of erosion of continental land masses during
the pre-agricultural period.
To derive the Hg content of this rock mass, we use
the rock types listed by Barth (1962) which comprise the
continental surface subject to erosion. For the Hg analy
ses of exposed igneous rock, it is considered that the
figure of 50 ppb as shown in Figure 2 for gneisses and
amphibolites, is applicable. These are rock types re
garded by Poldervaart (1955) as representative of shield
areas. Hg is somewhat higher (62 ppb) for the acidic in-
trusives and considerably lower (20 ppb) for plateau ba-
salts, and 50 ppb is a reasonable average. The values for
the sedimentary rocks are taken from Table 2. These areas
and Hg contents appear in Table 5.
TABLE 5
Mercury Content of Exposed Rocks
Percent of
Rock Type Continental Surface ppb Hg
Igneous 25 50
Shale 60 66
Sandstone 9 55
Limestone & Dolomite 6 40
The weighted average for all rocks subject to ero
sion is 60 ppb Hg. Applying this figure to the mass of
10^-0 t gives a quantity of 600 T yr“^ Hg carried to sea by
river discharge in pre-agricultural times. (This is an
upper limit, as an indeterminate amount must be sorbed on
river bottom sediments.) Using Holeman's estimate of
6 9
117 x 10 km^ of earth's surface subject to erosive loss
to sea (excluding interior drainage basins and continental
glacier floor) the rate of Hg loss per unit area amounts
to 5 g km" ^ yr"^-.
4. The pre-industrial cycle.
In a similar manner an estimate can be made of the
tonnage of Hg from natural sources, borne annually to sea
in pre-industrial times, a quantity that we assume is still
contributed by these sources. First the total river burden
is summed up: 35
TABLE 6
River Burden Carried to
T yr”^ -
Suspended load 18.3 x 10^
Bed load 1.8 x 10^
9
Dissolved load 4.3 x 10
Total 24.4 x 10^
The figure for total load multiplied by the Hg aver
age of 60 ppb as previously derived, gives 1460 T yr“^ Hg,
rounded off to 1500 T yr"^ as the quantity of natural Hg
transported to sea. This is also an upper limit, with an
unknown amount removed by bottom clays and oozes. The cor-
responding figure for Hg loss per unit area is 12.5 g km"''1
Recognizing the high degree of uncertainty involved,
we may also estimate, very roughly, the tonnage of Hg mo
bilized by weathering and transported either to sea or to
alluvial flood-plains. This estimate is desired because
it represents the actual background against which we can
compare the pollutional increment. As noted, it applies
to Cycles 3 and 4, the pre-industrial and modem cycles,
but not to Cycle 2, the pre-agricultural, when rivers were
generally graded and competent to carry a larger part of
their suspended load to sea. Taking the pre-industrial
Sea, World Wide
(Holeman, 1968)
(Judson, 1968, est. at
107o of suspended load)
(Poldervaart, 1955,
3.7 x lO1* g yr“l run
off, Gibbs, 1967,
avg. 115 ppm solids)
figure of 1500 T yr"1 discharged to sea, and applying the
factor for the Potomac River of 95% of the total detrital
load dropped as alluvium (a figure best considered a maxi
mum) , it appears that on a world-wide scale about 30,000 T
yr“l of Hg are mobilized from natural sources alone, by
weathering and erosion. By far the greater part (including
sorption losses from the 1500 T yr"'*' "discharged to sea"
is redeposited within continental borders.
A check is provided by Kothny's (1973) estimate of
11,500 T yr"l for Hg mobilized in river water and alluvium.
This contains a pollutional contribution, since it is based
partly on Hg in rainfall, but it does take into account the
large proportion of Hg deposited within continental bor
ders. The disparity between the two figures, 11,500 and
30,000 T, reflects the high degree of uncertainty in our
knowledge of the masses involved. The average is 20,750
which is rounded off to 20,000 T yr“l as the Hg flux for
the pre-industrial cycle for land and ocean deposition.
All estimates of Hg flux are summarized at this
poinjt in Table 7.
5. The modern cycle: General considerations.
The final computation required to develop the modern
Hg cycle is the determination of Hg losses to the environ
ment from man's activities, i.e., the pollutional increment.
If there existed a uniform and world-wide correspondence
between the two patterns of Hg dispersion, pre-industrial
and modern, it would be an easy task to estimate the pollu-
37
TABLE 7
Annual Transport Rate of
Mercury During Various Cycles
1. Primary
Cycle Hg, T yr"1
100
2. Pre-agricultural 600
3a. Pre-industrial,
marine deposition only 1,500
3b. Pre-industrial,
marine and terrestrial
deposition 20,000
tional contribution of Hg in a river, for example; we
would simply analyze its waters for Hg and multiply the
result by the appropriate factor. It is true that, com
paring the natural and artificial dispersion patterns, we
can find some major features in common. Most industrial
Hg is consumed in the large population centers which are
usually located on the lower reaches of major rivers,
i.e., the floodplains where the greater part of Hg in
alluvium is deposited. The same alluvial valleys like
wise receive a large share of the Hg-organic fungicides
consumed in agriculture, as well as the Hg dispersed to
the atmosphere in the combustion of fossil fuels. Base-
metal smelting, however, the source of much atmospheric
Hg, is more likely to be performed in mountain areas of
relatively light population. The Hg from this activity is
eventually scrubbed from the atmosphere by rainfall, but
since the average interval between rainfalls is ten days
(Hood, 1971), a steady wind of a few knots can disseminate
Hg from a smelter stack over half a continent.
On the other side of the ledger, there is a consider
able imbalance in the concentrations found in the natural
dispersion of Hg, due to the unequal distribution of this
element in the earth's crust. This is apparent from the
map showing the location of mercuriferous deposits (Figure
5, adapted from Bailey, 1973). The formation of such de
posits, and of ore bodies in general, has been the subject
of papers by Moiseyev (1971), Jfinks (1971), Krauskopf
(1971), Barnes (1967) and Tunell (1964), and need not be
given in detail here. As Figure 5 shows, Hg concentrates
in two belts coincidental with the two major volcanic
belts, i.e., one circumpacific, the other Caribbean -
Mediterranean - South Asian. The first accounts for the
mines of California and Mexico, the second for those of
Spain, Italy, and Yugoslavia. The Hg enrichment along the
oceanic ridges and rises is also shown on this map. This
latter enrichment has already been discussed in terms of
mantle origin and sea-floor spreading, but the relation to
the continental ore bodies is not immediately apparent.
This relation was provided, at least for those countries
bordering the East Pacific, by Noble (1970) and by Sillitoe
(1972), whose diagram of metals mobilization from subducted
oceanic crust is reproduced here as Figure 6. Noble gives
the sequence of metal ore deposits in the western United
States, ranging inland from the Pacific Coast, as Hg, Cu,
FIGURE 5
DISTRIBUTION OF MERCURY DEPOSITS, WORLD WIDE
■ p >
o
c?
2
n
e r
r v : *
Stippled areas denote
mercury deposits
i i i I i
After Bailey (1973)
Km
FIGURE 6
100 -
200 -
300 -
400 -
500
Oceanic crust
Moho
included
200 400 600 800 1000
Km
METAL PROVINCES IN WESTERN AMERICA
A fter S illit o e (1972)
Au, Ag, W, Pb, Mo, the highly mobile Hg being the first
to be expelled from the subducted material, and therefore
concentrated in the California Coastal Range. As expressed
by Sillitoe:
Much of the metals contained in post-
Paleozoic magmatogene ore deposits in
western America were derived from the
mantle at the East Pacific Rise...
carried toward the margins of the
Pacific Ocean Basin as components of
basaltic-gabbroic oceanic crust and
overlying pelagic sediments, and thrust
beneath the continents along inclined
Benioff zones. Metals were released
from the underthrust oceanic crust and
sediments during partial melting, and
incorporated in ascending bodies of
calc-alkalic magma... finally to be con
centrated in fluid phases associated with
the roof-zones of intrusive masses and
also with the comagmatic extrusive
rocks.
...Regions with particularly high
concentrations of ore deposits... might
be... zones beneath which higher than
normal quantities of metals were sub
ducted, due to a rapid rate of sea-
floor spreading, or to an above-average
rate of volcanism and metal production
on the corresponding segment of ocean
rise, or more fundamentally, to an in-
homogeneous distribution of metals in
the upper mantle beneath the ocean rise.
With both the natural and pollutional Hg subject to
such wide variation in their source concentrations, it
follows that their ratio, as computed in the following
section, does not apply on the regional scale, but is
valid as a world-wide average.
42
CHAPTER IV
THE POLLUTIONAL INCREMENT
1. Mercury from industry - agriculture.
The Hg pollutional increment can be divided into two
categories:
1. Hg extracted in mining operations and consumed
in industry, medicine, and agriculture. The
annual world production is known with a fair
degree of accuracy, but consumption and losses
to the environment are less certain, and are
estimated on the basis of figures for the United
States. Since this source of Hg is purposefully
exploited, our exposure to it amounts to a recog
nized (but uninformed) risk.
2. Hg in stack gases from smelters and fossil fuel
combusion. The quantity contributed by the for
mer is still highly conjectural. Hg from the
latter source is just beginning to be quantified,
and a major objective of this work is to provide
data for such quantification.
Between 1965 and 1969, annual world Hg production
fluctuated from 8000 to 9800 T with United States produc
tion slightly over 1/10 and United States consumption
slightly less than 1/3 (West, 1971). The average annual
growth rate for the five year period was 1.3%, which pro
jects to a production of 10,500 T in 1974. For the United
43
States, the balance of Hg production and consumption in
1968 appears in chart form in Figure 7 (data from Bailey,
1973). In that year, 21% of the consumption was recycled
or added to inventory. The rest, 79%, is eventually lost
to the environment. The same loss rate, if applied to the
world production of 10,500 T in 1974, would mean that 8300
T will eventually be released to the environment from this
source. Its half-life in the economy can only be conjec
tured, but a reasonable estimate would be a ten-year lag
from production to dissipation, with losses for 1974 re
flecting the production for 1964. On a world-wide basis,
therefore, about 7200 T of Hg will be dissipated to the en
vironment in 1974 from the sources shown on Figure 7. The
amount actually lost may be less than this figure, as more
stringent controls on discharges from chloralkali plants go
into effect, so a rounded figure of 7000 T yr"^ is adopted.
2. Mercury as a byproduct of smelting.
The only means available to measure the Hg discharge
from base metal smelting are indirect. An estimate was
made by Klein (1971) , based on the assumption that nearly
all the Hg vented to the atmosphere must come from the
large-scale smelting of the chalcophile metals Cu, Pb, and
Zn. Accordingly if we multiply the tonnage of Cu, for
example, that is produced annually, by the ratio of Hg to
Cu in the earth's crust, we obtain the tonnage of Hg pro
duced as an unrecovered byproduct of Cu smelting. Due to
44
FIGURE 7
FLOW OF INDUSTRIAL AND AGRICULTURAL MERCURY, IN
TONS, UNITED STATES, 1971
Stockpile
200
Inven -
tory . (148,
Agri
culture
Paints
Imports
Mining
248) Exports Total
Domestic
Consumption
Pharm a
ceutical
24
Recycled
380
Labor-'
atory
6
Catalysts
38
Measure
ment and 1140
control
Chlor
al kali
plants
Dental
Elec
300
trical
580
7
Unrecovered: 1430
Data from Bailey (1973)
45
its high volatility at the temperatures of the Cu roasting,
V
matte, and refining furnaces, the probability is high that
nearly all the Hg escapes through the stack. The predicted
Hg pollution from this source for 1974, based on Klein’s
figures for 1969, is 46,000 T yr“^, which is nearly 7 times
that resulting from industrial pollution and more than
twice the Hg mobilized from natural sources for alluvial
and marine deposition - the pre-industrial cycle.
In view of its magnitude, the premises for the esti
mate of 46,000 T must be carefully examined. The crustal
abundances for the metals are from Vinogradov (1962),
whose figure for Hg, 83 ppb, is about twice as high as
that determined from Table 4. Furthermore, it is presumed
that the ratio of Hg to base metal in ore bodies of the
latter is the same as their average ratio throughout the
earth's crust. But according to the Noble-Sillitoe hypo
thesis (Figure 6), the Hg-enriched areas are well separated
from those of the other metals, with the result that the
principal ore bodies are found in the California Coastal
Range; the Cu, Pb, and Zn are found in the Rockies and
Tri-State Area. Even with a common magmatic source, the
Hg will migrate further than the other heavy metals. To
quote Barth (1962):
Observations show that mercury, arsenic,
and antimony are found in low-temperature
deposits far from an igneous source...
lead (as galena) is often found farther
from the igneous source than are ores
of zinc and copper.
46
It may be argued, then, that the proportion of Hg in
the ores of the other three metals is significantly less
than that derived from crustal abundance figures.
A second method, also suggested by Klein, for arri
ving at Hg smelter losses, is to base them on Cu, Pb, and
Zn ore tonnages instead of refined metal, multiplying the
tonnages by their respective Hg contents. With ore pro
duction figures projected to 1974, this method yields
32,000 T Hg as the yearly smelter stack loss. The method
likewise depends on an unverified premise, i.e., that near
ly all the Hg is associated with the sulfide minerals and
very little with the gangue. Typically, sulfide ores are
concentrated by flotation, an example being that of El Ten-
iente, Chile, where an ore averaging 2% Cu was brought up
to a smelting grade of 32% Cu, dropping 95-99% of the gan
gue in the process. Any Hg included in the gangue must
consequently be subtracted from the smelter stack loss.
Parks (1974, personal communication) proposed the
computation of Hg smelter losses from Jonasson's figures
for Hg minimia and maxima in the principal Cu, Pb, and Zn
ore minerals. The results are shown in Table 8, the last
two columns being the range of Hg that would accompany the
predominant ore minerals sphalerite, galena, and chalcopy-
rite to the smelter. The minimum figure is a negligible
2.5 T of Hg, the maximum is 3200 T (projected figures for
the year 1974) . The arithmetic average is 1600 T yr“^ Hg.
To arrive at a better figure, samples of sphalerite
47
TABLE 8
Range of Possible Mercury Discharges from
Copper, Lead, and Zinc Smelting
Calculated from Reported Mercury Content
of Predominant Ore Minerals
Predominant Metal Production^- Estimated Normal Hg Range Estimated Hg
Mineral Projected to 1974 Mineral Tonnage1 in Mineral2 Lost in Smeltir
103 T 103 T ppm T yr-1
Min. Max. Min. Max.
Sphalerite 8,247 12,300 0.1 100 1.2 2400
Galena 4,606 5,320 0.004 70 0.2 360
Chalcopyrite 10,920 31,500 0.1 40 1.1 440
Total 2.5 3200 T Hg
^Calculated from data in Kimbell (1971).
2Jonasson (1972).
(Ottawa Co., Oklahoma), galena (Galena, Kansas), and chal-
copyrite (Rouyon District, Quebec) were obtained from
Ward's Natural History Establishment and analyzed for Hg as
described in Appendix 1 under Atomic Absorption Methods.
The Hg contents determined by these analyses were applied
to the figures for estimated mineral tonnages projected to
1974, taken from Table 8. The resulting estimated Hg
smelter loss, shown in Table 9, is 1215 T, rounded off to
1200 T yr-^. While it is recognized that the number of
samples is inadequate, this value is used as the best ob
tainable for that portion of the Hg pollutional increment
due to base-metal smelting.
3. Mercury from fossil fuels.
In 1971 there appeared two articles on the pollution
caused by combustion of fossil fuels that gave conflicting
views on the seriousness of their Hg contribution. One was
a paper by Joensuu (1971), giving analyses of 36 United
States coals with a mean Hg content of 3300 ppb. Taking a
more conservative estimate, 1000 ppb, Joensuu calculated
the resulting Hg pollution at 3000 T yr"^ on a world-wide
basis. On close appraisal (Magee, 1973) the mean value ap
peared biased on the high side as far as it purported to
represent a world average; nevertheless it stimulated much
effort in search of a better figure, including that portion
of this work dealing with coal analysis. Joensuu did not
find sufficient information on Hg in petroleum and base-
metal ores, however, to provide him with a reliable working
49
TABLE 9
Possible Mercury Discharges from Copper, Lead, and Zinc Smelting
Calculated from Mercury Analyses of Predominant Ore Minerals
Predominant
Mineral
Hg Content
ppm
Estimated 1974 _
Mineral Tonnage
Estimated Hg
Lost in Smelting
Sphalerite
Galena
Chalcopyrite
15
5
17
103 T
12,300
5,320
31,500
T yr'
652
27
536
-1
T O T A L 1,215 T Hg
^Calculated from data in Kimbell (1971).
figure for Hg from these sources.
The second paper, published soon afterwards, was by
Bertine (1971). It was more reassuring with respect to the
Hg contribution from coal combustion, but discomforting
with regard to petroleum. Using an older value of 12 ppb
for coal (Joensuu's work was published too late to include
in his estimate), Bertine allowed 1.7 T yr"^ as the Hg pol
lution from coal combustion. For petroleum he used the
only published figure available, 10 ppm, based on the mer-
curiferous Cymric field crudes, and this resulted in an
estimate of 1200 T yr"^ as the Hg contribution from petro
leum.
The figure of 12 ppb for coal derives from analyses
of German coals by Stock, using methods which would now
be considered inexact, and to which Stock’s own words are
applicable:
Wir betonten schon wiederhold, dass
die alteren Bestimmungen so kleiner
Quecksilbermengen (einschliesslich
der von uns selbst noch nach den
fruheren Analysenvorschriften
ausgefuhrten) wenig Vertrauen
verdienen.
The disparity between the two estimates, Bertine's
and Joensuu1s, illustrates the uncertainty that existed
only a few years ago regarding the pollutional Hg from
fossil fuels, and the extent to which a few anomalous
measurements can bias limited data. The Cymric crude oil
analysis likewise affected estimates of pollution by petro
leum, although the analyses themselves were prompted by
51
the observation of a highly unusual condition - the pre
sence of considerable free Hg in gas condensates (Stockman,
1947). Bailey (1961) recognized the Hg content as an ano
maly, and ascribed it to the location of this field on the
southeast prolongation of the Hg belt east of the San An
dreas Fault. To obtain the figure used here for Hg in pe
troleum, analyses published by Klein (1971) and Magee
(1973) have been averaged to give the value of 60 ppb. For
natural gas, Klein's figure of 40 ppb is used; in both
cases the resulting tonnages are small.
The sparseness of analytical data began to be recti
fied principally by government agencies and studies funded
by pollution control authorities. Hg analyses in the Uni
ted States coals were published by Kessler (1973) for 13
coals, O'Gorman (1972), 10 coals; Schlesinger (1972), 11
coals; Ruch (1973), 25 coals; and a listing (Magee, 1973)
of analyses by area, compiled from various sources, from
which our figures for Hg in United States coals are taken.
British figures, used here by permission, were provided by
Caldwell (1972, personal communication), Russian figures
are from the analysis of 3000 Donets coals (Karasich, quo
ted by O'Gorman, 1972), German figures from 5 Ruhr coals
analyzed in the course of this work (Table 10). Fossil-
fuel tonnages are from Kimbell (1971), with extrapolations
to 1974 based on production trends from 1965 to 1969.
4. Analysis of Hg in coal, peat, petroleum.
Analyses listed in Table 10 were performed by neutron
52
TABLE 10
Mercury Content of Fossil Fuels
U.S. coals Hg, ppb
Anthracite, Pittsburgh, Pennsylvania 80
Bituminous, Washington County,
Pennsylvania 340
Lignite, Bowman, North Dakota 110
Cannel, Morgantown, Kentucky 210
U.S. peat, Junius, New York 370
United Kingdom peat, Glastonbury, England 1200
German coals
Anthracite^, Ruhr 110
Gaskohle^, Ruhr 110
Fettkohle^, Ruhr 100
Gasflussigkohle^, Ruhr 170
Esskohle^, Ruhr 180
U.S. petroleums
San Joaquin Valley, sample No. 1 70
San Joaquin Valley, sample No. 2 100
^Anthracite type according to proximate analysis
(Appendix 3)
n
^•Bituminous type according to proximate analysis
(Appendix 3)
53
activation as described in Appendix 1, Analytical Methods.
United States coals and peats were obtained from Ward's
Natural History Establishment, Ruhr coals from the Ruhr-
kohle Aktiengesellschaft, and petroleum samples by courtesy
of Dr. Chilingar, University of Southern California.
The figure for German coals (Table 10), weighted
for the proportion of bituminous; anthracite of 12 : 1,
is 140 ppb. The samples available did not include the
lignites, which account for half the West German produc
tion and nearly all East German.
Magee's compilations for the United States coals are
given in Table 11.
TABLE 11
Mercury Content of United States
Coals, by Area
Hg, ppb
Appalachian 190
Interior, East 130
Interior, West 190
Southwest 60
Northern Plains 70
Since 95% of United States coals are taken from east
ern fields near the country's large population centers
(from Magee, as of 1964), the first two figures were used,
weighted toward the Appalachian value, to give a Hg value
of 170 ppb for the United States.
British coals contain from 200 to 400 ppb Hg, and
54
the mean figure of 300 ppb is used here.
For the Russian coals, Karasich's mean (quoted by
O'Gorman, 1972) of 860 ppb is accepted, recognizing that
they occur in a mercuriferous area and are higher in Hg
than the world average. Dvornikov (1967) noted two maxima
in his Hg analyses of coals from the same area, one at 20
ppb which he considered due to the natural geochemical
background, and a second at 500 ppb, reflecting local Hg
mineralization which produced Hg concentrations in coal as
high as 20,000 ppb.
Analytical data are available, therefore, for about
52% of world production, as shown in Table 12. The Russian
average, however, is not used in the "Rest of the World"
estimate.
TABLE 12
World Production and Mercury
Content for 1969
Coal
108 T
Hg Content
ppb
Hg, T
United States 5.18 170 88
West Germany 2.20 140 31
United Kingdom 1.53 300 46
U.S.S.R. 6.08 860 523
Rest of World 13.78 185* 255
Total 943
•^Weighted average from U.S., West Germany,
United Kingdom figures
55
Projecting an increase in coal production from 28.77
x 10® in 1969 to 32.3 x 10^ in 1974, we obtain an estimated
Hg tonnage of 1059 T as the pollutional increment from coal
combustion, which may be rounded off to 1100 T yr-^-.
About 90% of this tonnage enters the atmosphere di
rectly as Hg vapor in stack gas (Bolton, 1973), the re
maining 10% appearing as fly ash and furnace bottom ash,
which are disposed of as land or mine fill.
A curious consequence has ensued as a result of im
proved combustion technology during the present century.
While our utilization of fossil fuels has enormously in
creased, their toxic effects by inhalation may have shown
an actual decline. This is suggested by Kevorkian (1972)
on the basis of Hg analyses of samples of human tissue
from 59 autopsies preserved at the University of Michigan,
dating from the years between 1913 and 1970. Results were
somewhat inconclusive because of wide variations among
analysts, but in general showed a downward trend through
7 decades. Brain tissue, for example, ranged from 34.0 ppm
(1910 - 1919) to 1.3 ppm (1960 - 1969), with the sharpest
decline occurring around 1930. This decline Kevorkian as
cribes to the decrease in the direct combustion of coal
in homes. Cooking and heating needs are now met by cleaner
natural gas and fuel oil, while coal combustion is limited
to large power stations located on the city outskirts.
Evidently pollution can be ameliorated, as well as caused,
by technological adjustments.
56
No less fortuitously, the greater part of our coal
reserves, that of the western states, has a low Hg content,
as well as low S. As expressed in Table 13, (the figures
are from Schlesinger, 1972):
TABLE 13
United States Coal Reserves as of 1965
109 T Hg, ppb
Eastern 479 180
Western 1097 80
Total 1576 110
At the 1974 level of consumption, the country has
sufficient reserves for 3000 years, and our present energy
shortage is one of facilities rather than resources.
The next computation for Hg in fossil fuels is that
for petroleum, with a projected consumption in 1974 (a
figure subject to considerable downward revision) of
3.27 x 109 T with an average Hg content of 60 ppb. This
amounts to 200 T of Hg released to the environment by the
combustion of petroleum and its products.
The high Hg content of crude oil from the Cymric
field of the San Joaquin Valley in California has been
remarked. To see if this was typical of San Joaquin Val
ley crudes in general, samples from two wells in the valley
of indeterminate location, were analyzed for Hg (Table 10).
They showed 70 and 100 ppb Hg, i.e., only slightly above
the figure used as a mean for all petroleums. As in the
57
case of the Russian coals, anomalously high Hg contents
have resulted from proximity to a Hg deposit.
Finally a calculation is made for the pollutional in
crement due to Hg in natural gas. The estimated tonnage
for 1974 is 1.37 x 10^, with a Hg content of 40 ppb (Klein),
This yields a figure of 55 T discharged to the environment
from this source.
5. Compilations: The pollutional increment and
the modem cycle.
It is now possible to tabulate (Table 14) the pollu
tional increment of Hg from all major sources:
TABLE 14
Mercury Entering the Environment:
The Pollutional Increment
Source Hg, T yr"1
Industry - Agriculture
Purposeful consumption of Hg 7,000
Byproducts of Extractive Industries
Smelting - Refining 1,200
Fossil fuel combustion 1,355
Coal 1,100
Petroleum 200
Natural gas 55
Total 9,555
The total is rounded off to 10,000 T yr“^. We may say,
then, that industrialization has augmented by a factor of
1/2 the flow of Hg through the environment. As we shall
discover, this pollutional increment probably would not
tax the land's assimilative powers if it were evenly dis-
58
tributed. But as the Minimata incident revealed, Hg from
relatively small pollution sources can be trapped in stag
nant areas, its toxicity multiplied by methylation and its
concentration enhanced by passage up the food chain, whose
ultimate consumers fall victim to their own waste products.
A final compilation is made (Table 15) for Hg in all
four cycles, by combining Tables 7 and 14.
TABLE 15
Annual Transport Rate of Mercury, All Cycles
Natural Pollutional
Hg, T yr-1 Increment
Hg, T yr-1
1. Primary
2. Pre-agricultural
3. Pre-industrial
100
600
Marine deposition only 1,500
Marine + terrestrial deposition 20,000
4. Modern
Marine + terrestrial deposition 20,000
Industrial - agricultural
Smelting - refining
Fossil fuel combustion
7,000
1,200
1,355
Modem, total 29,555
The modem cycle Hg flux is rounded off to 30,000
T yr-' * ’.
CHAPTER V
OCCURRENCE OF MERCURY IN COAL
Be it known to all within the sound of
my voice: Whosoever shall be found
guilty of burning coal shall suffer
the loss of his head.
Edward I
1. Correlation coefficients.
Additional insight into the relation between Hg and
coal was sought by computing correlation coefficients of
Hg with major, minor, and trace elements present in coal.
It is postulated that associations of Hg with other ele
ments may occur in one or more of four ways:
1. Siderophile, chalcophile, lithophile geochemical
classification (Goldschmidt, 1957). Hg, being
chalcophile, would be found on this basis to
correlate with As, Cd, Cu, Ga, Pb, S, Sb, Se,
and Zn, and possibly with Fe, Ge, Sn, and Mo,
which sometimes have chalcophile properties.
2. Adsorption on clay minerals comprising the shaly
incombustible portion of coal. This would be
indicated by high correlations with K, Al, and
Si.
3. Substitutions for major mineral ions having
similar ionic charge and radius.
A. Selective uptake of Hg by the plants which are
incorporated into the coal measures, with forma
tion of metal-organic complexes. 60
For input, the report by Ruch (1973) of the Illinois
State Geological Survey, providing analytical data for 30
elements in 25 samples of coal having a mean Hg content of
240 ppb, was used with permission (Gluskoter, personal
communication) to compute correlation coefficients by the
Aerospace Corporation Program "CORRE" (Appendix 2). The
complete tabulation of correlations for all 30 elements is
of sufficient general interest to be given in its entirety
in Appendix 2, while Table 16 shows correlations for Hg
only:
TABLE 16
Correlation Coefficients for Mercury and
Other Trace Elements in Illinois Coals
Element Correlation
Coefficient
Element Correlation
Coefficient
Element Correlation
Coefficient
Pb 0.53 V 0.28 Mo 0.00
Ge 0.53 P 0.24 Sn -0.03
As 0.52 Mn 0.24 Al -0.04
Be 0.48 Cd 0.18 B -0.04
Sb 0.43 Zn 0.15 Cr -0.06
Ni 0.41 S 0.13 Cl -0.07
Ga 0.40 Zr 0.10 Ti -0.11
Cu 0.39 K 0.04 Br -0.17
Co 0.34 Ca 0.03 Mg -0.22
Fe 0.33 Se 0.03 Si -0.24
61
Of the eight elements analyzed which are classed as
purely chalcophile, all but Se show some degree of correla
tion with Hg, though the values for Cd, Zn, and S itself
are low. Of the four elements having some chalcophile pro
perties, Ge and Fe correlate with Hg; Mo and Sn do not.
The overall balance for Hg is one of general correlation
with other chalcophile elements. It is difficult, however,
to explain the correlation coefficient with Be of 0.48,
significant at the 0.01 level; the figure would seem more
appropriate with Bi but there does not appear to be any
possibility of confusion.
The negative correlation coefficients for Al and Si,
and the low values for K and Ca, argue against a relation
between Hg and the clays and feldspars, and the role of
adsorption as a concentration mechanism for Hg in coal.
Scavenging of Hg by Fe (OH)^ and MnC^, as suggested by
Jenne (1970), may play a minor role, resulting in the co
efficients of 0.33 and 0.24 respectively.
The factors that make for ready substitutions of
cations within a crystal lattice are: ionic radius, co
ordination number (of the oxide), percent ionic bond to
oxygen, and electronegativity. Table 17, from Krauskopf
(1967) shows the most likely possibilities for Hg sub
stitutions .
Of the 5 elements for which Hg substitution might
readily occur, only Ca is present to the extent of com
prising even a minor constituent in the Illinois coals,
62
TABLE 17
Substitution Factors for Mercury
Element Ionic
Radius
Ionic
Charge
Percent
Ionic
Bond
Coordi
nation
Number
Electro
negati
vity
ppm in
Illinois
coals
Ag 1.26 1 71 8 or 10 1.9
Ba 1.34 2 84 8 to 12 0.9
Ca 0.99 2 79 6 or 8 1.0
660
Hg
1.10 2 62 8 1.9 0.23
Pb 1.20 2 72 6 to 10 1.8 46
Sr 1.12 2 82 8 1.0
—
and its correlation with Hg is quite low (0.03).
Concei
vably some of the Hg might proxy for Pb (correlation co
efficient 0.53) if discrete minerals of the latter element,
e.g., galena, anglesite, are present in the coals. For
the samples considered, therefore, the evidence for sub
stitution is slight, with only one likely host mineral
present, and that one in low abundance.
Table 16 does not convey any information about selec
tive uptake of Hg by the living plants that produced the
Illinois coals, but there is a strong suggestion that such
uptake occurs in the high level of Hg in the Glastonbury
peat (1200 ppb) and the New York peat (370 ppb).
2. Relation of mercury to coalification.
What happens to the Hg during the long process of
conversion of plant to coal? The analysis of samples re
presenting every degree of coalification enables us to
trace the retention of Hg throughout the process. Starting
with a lignin-cellulose mixture with an indeterminate
amount of inorganics, principally shale, the process of
coalification involves anaerobic decay in a peat bog or its
Carboniferous equivalent, followed by burial, compaction
under heat and pressure with a decrease in hydrocarbons and
an increase in fixed, i.e., elemental C. Successive stages
in this process are designated peat, cannel (i.e., candle)
coal, lignite or brown coal, bituminous coal, and anthra
cite. The variable in the process is the proportion of vo
latile matter to fixed C, representing the degree of coal
ification. Qualitatively, it can be seen from Table 9
that, starting with peat (370 - 1200 ppb Hg) and ending
with anthracite (80 - 110 ppb Hg) there appears to be a
progressive loss of Hg. Such loss might be expected be
cause the conditions accompanying coalification - heat,
pressure, and a reducing environment - might also reduce
Hg^+ to the highly mobile Hg° vapor.
To test the hypothesis of Hg loss during coalifica
tion, a graph was prepared (Figure 8) plotting Hg versus
volatile matter as a percentage of total C. The figures
for volatiles and fixed C were computed, first, on a dry
basis, then normalized to 100% on an ash-free basis to eli
minate the variable amount of ash present in the samples.
A semi-logarithmic scale was selected for the plot because
the curve for Hg content must be asymptotic to a line re
presenting 100% volatiles. By the least-squares method,
64
Oi-hA
FIGURE 8
MERCURY VERSUS VOLATILES IN PEATS AND COALS
N. Y p e a t .O
50
o 40
o
H
L i g n i t e O
X
30
o
O O
20
10
100
(56) 200 1000 500
M e r c u r y , p p b
it was possible to construct a first-order curve, showing
that for samples as diversified as British peat, German an
thracite, and Pennsylvania bituminous, there is a direct
relation between Hg and volatiles. In other words, as vola
tile hydrocarbons are driven off or reduced to C, Hg is
driveti off also.
The points for the North Dakota lignite and the New
York peat do not fall on the curve, being deficient in Hg
with respect to the other samples. This probably reflects
a lack of Hg in the soils where the parent plants grew. It
is also worthy of note that the curve intersects the ab
scissa, representing zero volatiles, at the Hg value of 56
ppb. It may be argued, on somewhat tenuous ground, that
this is a stable and irreducible amount of Hg associated
with the ash in the form of HgS, while the Hg that is lost
was originally present as an unstable Hg-organic complex.
It is tentatively concluded that Hg associations in
coal are due to:
1. Its original occurrence in the soil that suppor
ted the growing plants, derived from rock wea
thering, and in natural association with other
chalcophile elements, particularly Pb, where
substitution of Hg in the crystal lattice of
galena, for example, may readily occur.
2. An uptake by those plant forms which are conver
ted to coal, with some concentration of Hg taking
66
place, as reflected by the high Hg content of
peat. It is conjectured that most Hg is present
as an Hg-organic complex with a stable inorganic
species present in the ash-forming minerals.
3. During coalification, progressive loss of Hg oc
curs, down to an irreducible level such as that
found in anthracite.
4. Although the Hg vs. volatiles graph (Figure 8)
shows a positive slope, i.e., low Hg corresponds
to an advanced degree of coalification, the
graph is not otherwise a guide to low-Hg coals.
These are determined primarily by the degree of
local Hg mineralization, the low-Hg North
Dakota lignite and the high-Hg Donets Basin
bituminous representing extremes in Hg content
that have little relation to the coalification
process.
67
CHAPTER VI
STEPS TOWARD MERCURY POLLUTION CONTROL
In a sense mining is an acceleration of the natural
erosional process. We strip the land for its minerals or
withdraw them from beneath the surface, refine their metal
content to a state that is unstable in contact with the
atmosphere, and dispose of them in alluvium and marine se
diments, sometimes locally concentrated to toxic levels.
The pre-agricultural flux of Hg through the environment
was 600 T yr“l; we may have speeded this up something like
fifty times.
To mention in detail all the measures that could be
taken for the control of Hg pollution would not be possible
here. A brief listing will be made, however, of those
areas where the principal obstacle to effective measures
seems to be a lack of information on sources and degree of
pollution, and a more detailed discussion is given of Hg
emissions from fossil-fuel combustion.
1. Because it is an important contributor to the
pollution picture, base-metal smelting must be
looked at more closely as a source of Hg. The
analysis of Hg in ore concentrates is advocated
as the first step in filling this data gap.
Stack emissions and the flow of Hg through
smelter operations also require checking.
2. Industrial leaks of Hg in wastes and sewage might
68
have been held to unobjectionable levels simply
by enforcement of the Rivers and Harbors Act of
1899, which prohibits the addition to navigable
waters of wastes other than domestic sewage hav
ing an impurities content higher than the water
itself. Lack of enforcement of the act was due
to two circumstances: a lack of sufficiently sen
sitive analytical methods, and a belief that what
could not be analyzed could scarcely be harmful.
The first circumstance has been alleviated by re
cent improvements in atomic absorption spectro
photometry; the second dispelled by studies of
concentration in the food chain, particularly of
DDT.
3. The continued use of DDT has been upheld as ne
cessary if we are to avoid crop failures and fa
mines. Similar criticism may be expected for
proposals to restrict the use of Hg-based seed,
pulp, and paint preservatives. Research should
therefore be undertaken to develop low-toxicity
and auto-degradable substitutes, in order to eli
minate the mercurials completely from applica
tions where they are broadcast to the environ
ment in handy food package form.
The growing awareness of weaknesses in our energy
base - shortage of easily extracted domestic fuels, depen
dence on foreign supplies subject to embargo, and environ-
69
mental damage from the exploitation of less accessible
sources - has stimulated interest in cleaning up combustion
products from high-S coals, which comprise the bulk of
eastern United States reserves. Experimental scrubber sys
tems for removing SO2 from power plant stack gases are now
on the line at Paducah, Kentucky, (Shawnee Power Station),
Pittsburgh, Pennsylvania (Phillips Power Station), Mohave,
Nevada (Mohave Power Station), and Joseph City, Arizona
(Cholla Power Station) , to name only those whose Hg con
tents have been studied by the author.
The presence of Hg in power plant flue gas has been
under investigation for several years, Billings (1972) re
porting a 31 pg m“^ Hg escaping out the stack, which he
estimated as 90% of that contained in the coal, while Bol
ton (1973) reported about 85% stack losses of Hg. Both
plants used electrostatic precipitators to remove particu
lates, but no SO2 scrubbers. The paths by which Hg subse
quently enters the environment from stack gases, ash, and
process water, are shown in Figure 9, after Swanson (1972).
Present scrubber systems are designed to take a sin
gle pollutant, SO2, out of the flue gas. The TCA unit of
the TVA's Shawnee Power Station at Paducah, Kentucky, may
be cited as an example. It contains, as the central com
ponent, a turbulent contact absorber (TCA), a spray tower
loaded with pingpong balls loosely confined in stratified
beds. Flue gas is admitted at the bottom, washed in a
countercurrent spray of limestone slurry, and vented at
70
FIGURE 9
CYCLE OF MATERIALS IN AND WASTE PRODUCTS OUT OF
A POWER PLANT
(Atmosphere?
Water
Power
Plant
Coal
Steam
Soil
Ash
Process
Water
Seepage
Bottom
. . Ash. >
Ash
Slurry
H g
Strip
Pit Ground
Water
A fte r Swanson (1972). Hg f lo w s . added.
the top. The SO2 is dissolved in the slurry liquor which
is withdrawn at the bottom, passing to a holding tank where
CaS03 precipitates; the latter is removed by filtration and
pumped as a sludge for disposal in a settling pond.
The coal comes from the Illinois fields described in
Ruch's (1973) report, and the average Hg content probably
approximates the 240 ppb given in that report. The ash
content is 12%, so if all the Hg were removed by the scrub
ber, the solids in the sludge (ignoring the limestone con
tribution) would have an Hg content of about 1000 ppb.
The figure actually determined was 2 ppm, indicating that
not much of the Hg escapes in the stack gas. While the
actual loss to the stack is probably a not inappreciable
figure, it is evident that the system may bS efficient for
the removal of Hg. While this work is still in an experi
mental phase, and before expensive capital investments have
been made, careful consideration should be given to the
efficiency of alternate scrubber system designs in removing
toxic trace metals, of which Hg is only one.
First a more fundamental question should be answered-
a question implicit in the quotation from Goldwater given
in the introduction,•"Tolerance for a potent substance not
infrequently grows into dependence on it..." We assume
that zero DDT pollution is a desirable goal because there
is no such thing as natural DDT. But is zero Hg pollution
an equally desirable goal?
A study was made by Cannon (1972) of the effects of
72
trace elements broadcast by the Four Corners Power Station,
San Juan County, New Mexico. She notes that certain trace
metals, i.e., B, Ba, Co, Cu, Mh, Mo, Sr, Ti, and Zn are
essential for plant growth; others - As, Be, Cd, Cr, Hg,
Ni, Pb, V and Zr - are not required, or possibly are re
quired only in very small amounts. The facts are that the
thin desert soils of San Juan County are deficient in the
vital trace elements, and even with the increment in the
form of fallout from the power plant, they are below the
national average in most of these elements. In effect,
the Four Comers plant is distributing fertilizer over the
countryside from its stacks. Perhaps the only harm that
results is a high localized concentration of the most
toxic metals in the near vicinity of the station; when di
luted by atmospheric mixing and spread over several states,
they may be innocuous or even beneficial. We are reminded
of Kevorkian's work with autopsied brain tissues; perhaps
the trend toward construction of large isolated power
plants has diminished the danger of pollution, or even
turned it to our advantage. The power plant of the future
may be intentionally utilized as a disseminating device for
renewing soils that are depleted of essential elements, and
for enriching the seas with food for the phytoplankton.
Anyone who has seen the barren countryside downwind
from a large smelter realizes the need for emissions con
trol, particularly for SC^. Neither is it possible to dis
miss the dumping of three thousand tons of Hg into the at-
73
mosphere yearly, as a matter of no public concern. It is
possible, however, that the answer to the problem of trace
metals in scrubber effluent gases may be to use this as the
pathway for their disposal, building our stacks lofty
enough to avoid dangerous local concentrations, rather than
impounding the toxic materials in a form where they may
readily be leached into water supplies.
To any suggestion of the need to control pollution,
the response is frequently made "There is no conclusive
proof of harm; further studies are needed." With the
Minamata experience in mind, it is only prudent to apply
obvious and immediate measures to reduce Hg discharges.
But for long-term planning, we must also consider imagina
tive and unconventional approaches - measures that empha
size recovery instead of dumping. Only by turning our
waste products into resources can adequate supplies be
assured for generations to come.
74
ACKNOWLEDGEMENTS
I am indebted to the following individuals
for providing facilities, information, and
advice in support of this work.
Dr. James Bischoff, Department of Geological
Sciences, University of Southern California,
who suggested the topic.
Dr. James Warf, Department of Chemistry,
University of Southern California.
Dr. Kenneth Chen, Environmental Engineering
Projects, University of Southern California.
Dr. George Parks, Department of Earth
Sciences, Stanford University, who reviewed
the manuscript and offered much valued
criticism.
Appendix 1
Analytical Methods
\
Appendix 1
I. Analytical Methods
1. Preparation of samples.
The analysis of Hg in trace amounts requires
special precautions against loss by volatization, and
against contamination by the many sources of metallic
Hg commonly found in laboratories. Jenne (1970), for
example, comparing soil analyses on freshly sampled versus
stored materials, found Hg losses to run as high as 42%
after two days' storage in sealed containers at 20°.
Fleischer (1970), noting the discordant results obtained
in analyses of USGS standard rocks, considered the gen
erally higher early results as indicative of Hg contami
nation, but in view of Jenne's findings, the question
arises whether the first analyses might not be correct,
and the latter results low due to volatization loss.
The possibility is illustrated by four neutron activation
analyses of USGS G-l granite made over a period of five
years (Fleischer), which when plotted against time, show
a uniform downward trend amounting to nearly 10% per
year (Figure 10).
To determine whether the coal samples listed in
Table 9 may have been subject to such loss, a portion of
NBS 1630 standard coal was placed in an open petri dish
and stored at 80° for one month. The Hg content, as de
termined by neutron activation analysis (q.v.) was found
77
Mercury, ppb
FIGURE 10
MERCURY IN USGS G-l GRANITE
AS ANALYZED OVER A FIVE YEAR PERIOD
(Neutron activation analysis)
300,
200
100.
Data from F leisch er (1970)
68 66 69 67 65 64
Year
to be slightly higher than the control stored at room tem
perature. Therefore, it was concluded that storage of
coal samples analyzed in this work did not result in signi
ficant loss of Hg. It is recommended as good practice,
nevertheless, to analyze samples as soon as possible after
comminution, and to store them in sealed containers in
areas not subject to Hg contamination.
2. Neutron activation analysis.
The method used for the greater number of analy
ses described here was neutron activation, since at the
time the work was undertaken it was the only one sensitive
to 0.01 g Hg (5 ppb in a 2 g sample) considered necessary
for the materials balance. It has the further advantages
of eliminating blank corrections, since Hg introduced after
irradiation does not affect the activity count, and of cor
recting for volatilization losses. Such losses are sub
stantial (Gorsuch, 1959; Merodio, 1961), but the use of a
Hg carrier-monitor makes them easily correctible.
A schematic diagram of the radiochemical separation
following neutron activation is presented in Figure 11,
with the step-by-step description as follows:
1. Samples of the United States coals and South
African kimberlite were received in lump fora,
outer surfaces were chiseled off, and centers
were milled in a porcelain mortar to -60 mesh.
The Ruhr coal samples were received in a finely
pulverized condition, sealed in plastic bags.
f i g u r e 1 1
Diagram of Analytical Method for Mercury
by Neutron Activation
Glycine,
HCIO3
H2S
Weigh
Correction
for
Moisture
Count H g ^
Activity
F ilter-
discard
Irradiate
sample as
received
Digest
with acid
S i0 2,
trace
metals -
discard
Filter
Distill
over
HgCI2
The New York peat was in shredded form and re
quired no further preparation; the United King
dom peat was milled to a fine powder.
All samples were run singly as received (after
milling if necessary). Moisture was determined
on separate portions of approximately 1 g,
which was dried over for one week. Final
Hg content was computed on a dry basis.
Samples were weighted into high-purity poly
ethylene vials.
Weight ranges were:
Coals 2.5 to 4.5 g
Peat 0.9 to 2.6 g
Petroleum 3.6 to 3.8 g
Kimberlite 4 g
Irradiation was done in the Triga reactor of
the Intelcom Company, San Diego, for one half
1 3
hour at a neutron flux of 1.8 x 10 neutrons
-2 -1
cm ^ sec .
After a waiting period of 22 hours to allow
for the decay of short-life activities, sam
ples were transferred to 125 ml Erlenmeyer
flasks.
Quantities of HgCNOg^ carrier, averaging 30 mg
were added to each flask.
10 ml concentrated was added to each
sample and digestion begun on the hot plate.
81
8. Concentrated HNOg was added by medicine dropper,
1 ml at a time, waiting between additions until
brown fumes disappeared. Digestion was contin
ued until black carbonaceous matter was gone and
solution was light straw color.
9. The flask was cooled and boileezers added, plus
2 ml glycine solution (60 g / 100 ml H^O) , and
5 ml conc. HClOg, in order to distill over Hg
as HgC^. This process (Sjostrand, 1964) , by
reduction of HCIO^ with glycine, generates HC1
continuously during the distillation. If HC1
itself were used, most of it would distill over
before evolution of HgC^. Distillation turns
the volatility of HgCl^ to advantage by separa
ting Hg from other trace metals except As.
The most important of these separations is that
from Au, which has an activity almost coincident
with that of Hg.
10. The stillhead was attached and distillation con
tinued for one half hour, heating with bunsen
burner and trapping distillate under ^ 0 in an
ice bath.
11. The distillate was diluted to 50 ml and HgS
precipitated with I^S.
12. HgS was removed by filtration through Whatman
No. 40 paper.
13. The HgS precipitate was washed off the paper
using a minimum quantity of water, disregarding
traces, into a tared A1 weighing dish.
14. The HgS was dried and weighed to determine Hg
recovery.
15. The Hg^^ activity at 77 keV was counted 22 to
48 hours after separation, using a Northern
Scientific 4096 channel counter and 52 cm^
Princeton Gamma-Tech Ge-Li detector.
16. To obtain Hg content, sample counts were compar
ed to those obtained on the NBS 1630 standard
coal sample containing 130 ppb Hg. Because of
irradiation costs, it was impractical to run re
plicate samples, but a duplicate check was affor
ded by the two NBS samples, one stored at room
temperature, the other at 80°. Referred to a
mean of 130 ppb, the sample held at R.T. showed
120 ppb Hg, that held at 80° showed 140 ppb Hg.
This gives an average deviation from the mean of
+ 5%, which compares well to Bolton's (1973) de
termination of + 8% for similar samples run by
NAA.
3. Atomic Absorption analysis.
Within recent years the development of the graph
ite furnace as the activating source for atomic absorption
has extended the sensitivity of the instrument to the point
where it is fully as useful as neutron activation, with a
considerable saving in money and effort. With the instru
ment attachments described here, it would now be considered
favorably for all Hg analyses.
Atomic absorption spectrophotometry was done on the
Perkin-Elmer Mod. 303 instrument with graphite furnace and
deuterium background corrector attachments. Solid samples
were prepared by chiseling off outer surfaces, crushing
center portions with a hammer, and milling in a porcelain
crucible. Liquid samples were concentrating by extracting
Hg into CHClg-dithizone solution and pipetting an aliquot
into the furnace.
4. Proximate analysis of coal and peat.
For proximate analyses, samples of coal and peat,
prepared for NAA by milling, were run as received and cor
rected to a dry basis. Volatile matter + H2O was found by
heating a 2 g sample in a nearly covered Vycor crucible
over a low bunsen flame for a two hour period, with oc
casional rabbling. The method is not a standard one, but
is adequate for comparative purposes.
Ash is determined by igniting the uncovered sample
in the full heat of the burner, with occasional rabbling,
and fixed C is the difference: (sample - volatiles) -
ash.
84
Appendix 2
Mercury in Coal:
Correlation Coefficients
TABLE
COREELATION COEFFICIENTS: MINOR AND
Al As B Be Br Ca Cd Cl Co Cr Cu Fe Ga Ge
A1 1.00 -.39 .28 .13 -.13 -.15 .13 .10 -.07 .32 .17 -.09 .17 -.4 A
AS 1.00 -.18 .50 -.25 -.04 .02 -.20 .76 -.24 .61 ■ '.28 .65 .76
B 1.00 .08 -.42 .54 .23 -.38 -.11 .06 -.15 .07 .12 .15
Be 1.00 -.45 -.22 .36 -.17 .57 .04 .40 .41 .46 .57
Br 1.00 -.42 -.09 .08 -.25 -.15 .00 -.74 -.34 -.56
Ca 1.00 .11 -.28 -.18 -.17 -.34 .05 .01 .31
Cd 1.00 -.33 .00 .17 .16 -.11 .15 .26
Cl
1.00 -.05 .17 -.15 .16 -.26 -.31
Co
1.00 -.11 .48 .20 .52 .54
Cr
1.00 -.12 .10 .05 -.15
Cu
1.00 -.09 .58 .26
Fe 1.00 .13 .46
Ga 1.00 .59
Ge
1.0C
Hg
K
Mg
Mn
Mo
Ni
P Computation of correlation coefficients, r ,
Pb by Aerospace Corporation subroutine "COREE**
S
Sb S.
jk
•jk
Se
f \AiT V skk
Zn
Zr where j = 1, 2, . ...m; k= 1, 2, ... .m;
S = sums of cross-products of deviations
from means.
TABLE . 18
iRRELATION COEFFICIENTS: MINOR AND TRACE ELEMENTS IN ILLINOIS COALS
Co Cr Cu Fe Ga Ge i- Hg K Mg Mn Mo Ni P Pb S
-.07 .32 .17 -,09 .17 -.44 -.04 .75 .53 -.07 .31 .01 .22 -.13 -.19
.76 -.24 .61 .'.28 .65 .78 .52 -.19 -.28 .17 -.20 .71 .20 .77 .15
-.11 .06 -.15 .07 .12 .15 -.04 -.10 .11 .65 .02 .07 -.30 -.18 .35
.57 .04 .40 .41
.46 .57 .48 .07 -.04 .27 .07 .56 .05 .79 .26
-.25 -.15 .00 -.74 -.34 -.56 -.17 -.09 -.18 -.57 -.41 -.43 .27 -.50 -.60
-.18 -.17 -.34 .05 .01 .31 .03 -.28 -.03 .49 .04 -.10 -.26 -.10 .12
.00 .17 .16 -.11 .15 .28 .18 .04 .04 .36 .18 .21 -.17 .04 .05
-.05 .17 -.15 .16 -.26 -.31 -.07 .12 .08 -.40 .19 -.14 -.07 -.08 -.07
1.00 -.11 .48 .20 .52 .54 .34 .02 -.13 .03 -.02 .84 .00 .71 -.03
1.00 -.12 .10 .05 -.15 -.06 .34 .34 .18 .44 .06 .07 -.20 .16
1.00 -.09 .58 .28 .39 .26 -.03 .07 -.03 .56 .54 .49 -.11
1.00 .13 .48 .33 -.02 .09 .38 .33 .30 -.34 .49 .73
1.00 .59 .40 .26 .07 .28 .11 .69 .34 .43 .12
1.00 .53 -.31 -.26 .54 .07 .67 -.11 .65 .47
1.00 .04 -.22 .24 .00 .41 .24 .53 .13
1.00 .43 -.10 .36 .08 .42 .04 -.15
1.00 .20 .22 .00 .08 -.21 .03
1.00 -.04 .27 -.17 .07 .54
1.00 .25 -.31 -.01 .35
1.00 .04 .60 .19
its, r •T- §
1.00 .09 -.48
CORRE
ak
1.00 .04
1.00
• • I t l 7
ations
; ELEMENTS IN ILLINOIS COALS
K Mg Mn Mo Ni P Pb S Sb Se Si Sn Ti V Zn Zr
.75 .53 -.07 .31 .01 .22 -.13 -.19 -.43 .27 .76 -.18 .76 .33 .20 .09
-.19 -.28 .17 -.20 .71 .20 .77 .15 .86 -.07 -.61 -.13 -.38
i
•
i - *
0 0
i
•
o
-.11
-.10 .11 .65 .02 .07 -.30 -.18 .35 -.11 .07 .35 .31 -.21 -.33 .12 -.18
.07 -.04 .27 .07 .56 .05 .79 .26 .42 .04 -.17 -.06 .02 .11 .39 -.27
-.09 -.18 -.57 -.41 -.43 .27 -.50 -.60 -.47 -.17 -.31 -.10 .30 -.08 -.11 .11
-.28 -.03 .49 .04 -.10 -.26 -.10 .12 .18 -.10 .25 .16 -.35 -.23 .00 -.06
.04 .04 .36 .18 .21 -.17 .04 .05 .23 .15 .12 .17 .07 .12 .88 -.26
.12 .08 -.40 .19 -.14 -.07 -.08 -.07 -.20 .21 .13 -.07 .08 .49 -.26 .11
.02 -.13 .03 -.02 .84 .00 .71 -.03 .63 -.04 -.32 -.24 -.07 .00 .12 -.15
.34 .34 .18 .44 .06 .07 -.20 .16 -.04 .30 .34 -.09 .16 .52 .17 .35
.26 -.03 .07 -.03 .56 .54 .49 -.11 .35 .24 -.27 .00 .13 -.12 .22 -.16
-.02 .09 .38 .33 .30 -.34 .49 .73 .44 .07 .05 .18 -.40 .24 -.10 .09
.26 .07 .28 .11 .69 .34 .43 .12 .57 -.08 -.13 -.25 -.02 -.12 .22 .05
-.31 -.26 .54 .07 .67 -.11 .65 .47 .86 -.07 -.41 .06 -.62 -.18 .26 -.19
.04 -.22 .24 .00 .41 .24 .53 .13 .43 .03 -.34 .03 -.11 .28 .15 .10
1.00 .43 -.10 .36 .08 .42 .04 -.15 -.23 .13 .53 -.21 .68 .52 .12 .15
1.00 .20 .22 .00 .08 -.21 .03 -.16 .14 .62 .00 .27 .28 .09 .53
1.00 -.04 .27 -.17 .07 .54 .33 .01 .09 .34 -.48 -.17 .21 .08
1.00 .25 -.31 -.01 .35 .12 .43 .47 -.03 .06 .46 .38 -.05
1.00 .04 .60 .19 .71 .27 -.17 -.08 -.18 -.01 .32 -.06
1.00 .09 -.48 -.11 .03 -.08 -.13 .43 .02 -.16 .28
1.00 .04 .67 .01 .17 .10 .14 .12 ,05 -.31
1.00 .33 .18 -.04 .21 -.65 .01 .04 -.22
1.00 . .04 -.41 -.11 -.49 .00 .18 -.03
1.00 .28 -.02 .06 .27 .11 -.09
1.00 .02 .47 .26 .17 .11
1.00 -.30 -.18 .10 -.03
1.00 .37 .14 .12
1.00 .12 . 22Z
1.00 -.3]
1.0C
86
Appendix 3
Proximate Analysis of Coals and Peats
Appendix 3
Proximate Analysis of Coals and Peats
Source
Volatiles
%
Dry Basis
Fixed C
%
Ash
%
Anthracite, Pennsylvania 10.6 76.1 15.5
Bituminous, Pennsylvania 28.1 66.7 5.2
Lignite, North Dakota 32.8 57.7 9.1
Cannel*, Kentucky 14.0 67.0 19.0
Peat, New York 58.0 38.5 3.5
Peat, England 51.8 44.7 3.7
Anthracite, Ruhr 0.8 93.8 5.6
Gaskohle, Ruhr 5.8 89.7 4.5
Fettkohle, Ruhr 12.4 80.8 7.1
Gasflussigkohle, Ruhr 23.9 72.0 4.2
Esskohle, Ruhr 23.6 70.9 7.4
*This sample had the luster and fracture of a cannel coal,
but the volatiles content is atypical. 50% volatiles
would be closer to the norm for caiinel.
88
REFERENCES
Aidin'yan, N. Kh., Ozerovna, N. A., Gipp, S. K. (1963).
The problem of the distribution of mercury in contem
porary sediments. Akad. Nauk. S.S.R. Trudy Inst.
Geol. Rudn. Mestorozhd., Petrog. Mineral. Geokhim.
99, p. 5-11. (Translation) Chem. Abstr. ,59, p. 7262.
Bailey, E. H. , Snavely, P. D. Jr., White, D. E. (1961).
Chemical analysis of brines and crude oil, Cymric
field, Kern County, California. USGS Prof. Paper
424D, p. D306-D309, USDI, Wash. D. C.
Bailey, E. H., Clark, A. L. , Smith, R. M. (1973). Mercury.
From: United States Mineral Resources, USGS Prof.
Paper 820, p. 401-414.
Barnes, H. L. , Romberger, S. B., Stemprock, M. (1967).
Ore solution chemistry. II: Solubility of HgS in
sulfide solution. Econ. Geol. 62, p. 957-982.
Barth, T. F. W. (1962). Theoretical petrology. Wiley,
N.Y., 2nd Ed.
Bertine, K. K. , Goldberg, E. D. (1971). Fossil fuel com
bustion and the major sedimentary cycle. Science,
173, p. 233-235.
Billings, C. E., Matson, W. R. (1972). Mercury emission
from coal combustion. Science 176, p. 1232-1233.
Birke, G. , Johnels, A. G. , Plantin, L. 0., Sjostrand, B. ,
Skerfving, S., Westermark, T. (1972). Studies on
humans exposed to methyl mercury through fish con
sumption. Arch. Environ. Health 25_, 2, p. 77-91.
Bolton, N. E., Van Hook, R. I., Fulkerson, W. , Lyon, W. S.,
Andren, A. W., Carter, J. A., Emery, J. F. (1973).
Trace element measures at the coal-fired Allen steam
plant. Progress report, June 1971 - Jan. 1973.
ORNL-NSF-EP-43, Oak Ridge Nat'l Lab., Oak Ridge, Tenn.
Bostrom, K. , Fisher, D. E. (1969). Distribution of
mercury in East Pacific sediments. Geochim. Cosmochim.
Acta 33, p. 743-745.
Cannon, H. L., Anderson, B. M. , (1972). Southwest energy
study. Report of the coal resources work group.
Part III: Trace element content of the soils and
vegetation in the vicinity of the Four Corners
Power Plant. Feb. 1972. USGS, Denver. USDI, Wash.
D. C.
89
Conway, E. J. (1942). Mean geochemical data in relation to
oceanic evolution. Roy. Irish Acad. Proceed. 48,
sec. B, p. 119-159.
Corliss, J. B. (1971). The origin of metal-bearing sub
marine hydrothermal solutions. J. Geophys. Res.
76, 33, 0. 8128-8138.
Cranston, R. E., Buckley, D. E. (1972). Mercury pathways
in a river and estuary. Environ. Sci. 6c Tech. 6,
3, p. 274-278.
Dall'Aglio, M. (1968). The abundance of mercury in 200
natural water samples from Tuscany and Latium
(Central Italy). From: Origin and distribution of
the elements, Ahrens, L. H., (Ed.), Pergamon, N.Y.,
p. 1065-1081.
D'ltri, F. M. (1972). The environmental mercury problem.
Chem. Rubber Co., Cleveland, 0.
Douglas, I. (1967). Man vegetation, and the sediment
yields of rivers. Nature 215, p. 925-928.
Dvornikov, A. G. (1967). Some features of mercury-con
taining coals of the eastern Donbass (Rostov region).
Dokl. Akad. Nauk U.S.S.R., 172, p. 199-202.
(Translation) Chem. Abstr. 66, p. 5450.
Eriksson, E. (1959). The yearly circulation of chloride
and sulfur in Nature: Meteorological, geochemical,
and pedological implications. Part II. Tellus 12,
1, p. 63-109.
Eshleman, A., Siegel, S. M., Siegel, B. Z. (1971). Is
mercury from Hawaiian volcanoes a natural source of
pollution? Nature 233, p. 471-472.
Fleischer, M. (1970). Summary of the literature on the
inorganic geochemistry of mercury. From: Mercury
in the Environment, USGS Prof. Paper 713, USDI,
Wash. D. C., p. 6-13, 53.
Gibbs, R. J. (1967). The geochemistry of the Amazon River
Basin. Part I. Geol. Soc. Amer. Bull. 78, p. 1203-
1232. “
Goldschmidt, V. M. (1958). Geochemistry. Oxford Univ.
Press, London.
Goldwater, L. J. (1971). Mercury in the environment. Sci.
Am. 224, 5, p. 15-21.
90
Gorsuch, T. T. (1959). Radiochemical investigations on
the recovery for analysis of trace elements in organic
and biological materials. Analyst 79i, p. 135-173.
Green, J. (1972). Elements: Planetary abundances and
distribution. From: Encyclopedia of geochemistry and
environmental sciences. Fairbridge, R. W., (Ed.),
p. 268-300, Van Nostrand Reinhold Co., N.Y.
Gregor, B. (1970). Denudation of the continents. Nature
228, p. 273-275.
Hem, J. D. (1970). Chemical behavior of mercury in aqueous
media. From: Mercury in the environment. USGS
Prof. paper 713, p. 19-24. USDI, Wash., D.C.
Holeman, J. N. (1968). The sediment yield of major rivers
of the world. Water Resources Rev. 4, p. 737-747.
Hood, D. E., (Ed.), (1971). Impingement of man on the
oceans. Wiley-Interscience, N.Y.
Horn, M. K. , Adams, J. A. S. (1966). Computer-derived
geochemical balances and element abundances.
Geochira. Cosmochim. Acta 30, 3, p. 279-297.
Irukayama, K. , Fujiki, M. , Kai, F., Kondo, T. (1961).
Studies on the origin of the causative agent of
Minamata disease. 1. Organic mercury compounds in
the fish and shellfish of Minamata Bay. Kumamoto
Med. Jour. 14, p. 157.
Jenks, W. F. (1971). Tectonic transport of massive sul
fide deposits in submarine volcanic and sedimentary
host rocks. Econ. Geol. 66, p. 1215-1224.
Jenne, E. A. (1970). Atmospheric and fluvial transport of
mercury. From: Mercury in the environment, USGS
Prof. paper 713, p. 40-45. USDI, Wash., D. C.
Joensuu, 0. I. (1971). Fossil fuels as a source of mercury
pollution. Science 172, p. 1027-1028.
Jonasson, I. R. , Boyle, R. W. (1972). Geochemistry of
mercury and origins of natural contamination of the
environment. Can. Min. Metall. Bull., Jan. 1972.
Judson, S. (1968). Erosion of the land. Amer. Sci. 56,
p. 356-374. ~
91
Kessler, T., Sharkey, A. G. Jr., Friedel, R. A., (1973).
Analysis of trace elements in coal by spark-source
mass spectrometry. BuMines Report of Investigations
7714, USDI, Wash. D. C.
Kevorkian, J., Cento, D. P., Hyland, J. H., Bagozzi, W. M.,
v. Hollebecke, E. (1972). Mercury content of human
tissues during the Twentieth Century. Amer. J. Pub.
Health, Apr. 1972, p. 504-513.
Kimbell, C. L. (1971). Minerals in the world economy.
From: Minerals Yearbook 2, 1969, p. 1-61, USDI,
Wash. D. C.
Klein, D. H., (1971). Sources and present status of the
mercury problem. From: Mercury in the Western
Environment Conf., Portland, Oregon, February 25-26,
1971.
Kothny, E. L., (1973). The three-phase equilibrium of
mercury in nature. From: Trace elements in the
environment, p. 48-80. Kothny, E. L. (Ed.), Amer.
Chem. Soc., Wash., D. C.
Krauskopf, K. B. (1967). Introduction to geochemistry.
McGraw-Hill, N.Y.
Krauskopf, K. B. (1971). The source of ore metals.
Geochim. Cosmochim. Acta 35, 7, p. 643-659.
Kuenen, P. H. (1941). Geochemical calculations concerning
the total mass of sediments in the earth. Amer. J.
Sci. 239, 3, p. 161-190.
Leatherland, T. M., Burton, J. D., McCartney, M. J.,
Culkin, F. (1971). Mercury in north-eastern
Atlantic Ocean water. Nature 232, p. 112.
List, R. J. (1958). (Ed.), Smithsonian Meteorological
Tables. 6th Ed., Smithsonian Inst., Wash., D. C.
Livingstone, D. A. (1963). Chemical composition of rivers
and lakes. From: Data of geochemistry. USGS Prof.
paper 440-G, USDI, Wash., D. C.
Magee, E. M. , Hall, H. J., Varga, G. M. Jr., (1973).
Potential pollutants in fossil fuels. EPA-R2-73-249.
Esso Research & Engr. Co., Linden, N. J.
Marowsky, G., Wedepohl, K. H. (1971). General trends in
the behavior of Cd, Hg, Tl, and Bi in some major rofck
forming processes. Geochim. Cosmochim. Acta 35,
p. 1255-1267. ~ 92
Mead, W. J. (1914). The average igneous rock. J. Geol.
22, p. 772-781.
Meade, R. H. (1969). Errors in using modem stream-load
data to estimate natural rates of denudation. Geol.
Soc. Amer. Bull. 80, p. 1265-1274.
MerSdio, J. C. (1961). Separaci6n y valoraci6n de
pequenas cantidades de mercdrio en materia org£nica.
Xnales Asoc. Qulm. Argent. 49, p. 225-236.
Miller, B. E., Grant, P. M., Kishore, R. , Steinkruger,
F. J., Rowland, F. S., Guinn, V. P. (1972). Mercury
concentrations in museum specimens of tuna and sword
fish. Science 175, p. 1121-1122.
Moiseyev, A. N. (1971). A non-magmatic source for
mercury ore deposits? Econ. Geol. 66, p. 591-601.
Moore, G. T. (1969). Interactions of rivers and oceans -
Pleistocene petroleum potential. Amer. Asso. Petr.
Gas Bull. 53/12, p. 2421-2430.
Noble, J. A. (1970). Metal provinces of the western
United States. Geol. Soc. Amer. Bull. 81, p. 1607-
1624.
O'Gorman, J. V., Suhr, N. H., Walker, P. L. Jr. (1972).
The determination of mercury in some American coals.
Appl. Spectroscopy 26, 1, p. 44-48.
Onishi, H., Sandell, E. B. (1955). Geochemistry of
arsenic. Geochim. Cosmochim. Acta 7 _ , p. 1-33.
Poldervaart, A. (1955). Chemistry of the earth's crust.
From: Crust of the Earth, Geol. Soc. Amer. Spec.
Paper (32, p. 119-144.
Rankama, K., Sahama, T. G. (1950). Geochemistry.
Chicago Univ. Press, Chicago, 111.
Ruch, R. R., Gluskoter, H. J., Shimp, N. F. (1973).
Occurrence and distribution of potentially volatile
trace elements in coal: An interim report. 111.
State Geol. Survey, Environ. Geol. Notes 61, Apr.
1973.
Schroeder, H. A. (1971). Metals in the air. Environment
13, 8, p. 18-32.
93
Schlesinger, M. D., Schultz, H. (1972). An evaluation of
methods for detecting mercury in some U. S. coals.
BuMines Report of Investigations 7609, USDI, Wash.,
D. C.
Sillitoe, R. E. (1972). Relation of metal provinces in
western America to subduction of oceanic lithosphere.
Geol. Soc. Amer. Bull. 83, p. 813-818.
Sjostrand, B. (1964). Simultaneous determination of
mercury and arsenic in biological and organic
materials by activation analysis. Anal. Chem. 36,
4, p. 814-819.
Smith, J. D., Nicholson, R. A., Moore, P. J. (1971). Mer
cury in water of the tidal Thames. Nature 232, p.
393-394.
Skirrow, G. (1965). The dissolved gases - carbon dioxide.
From: Chemical Oceanography, Riley, J. P. and Skir
row, G., (Eds.), Academic Press, London, p. 227-322.
Stock, A., Cucuel, F. (1934). Die verbreitung des Queck-
silbers. Die Naturwissenschaften 22^, 22-24, p.
390-393.
Stockman, L. P. (1947). Mercury in three wells at Cymric.
Petroleum World 3, p. 37.
Storrs, B., Thomson, J., Fair, G., Dickerson, M. S.,
Nickey, L., Barthell, W., Spaulding, J. E. (1970).
Organic mercury poisoning. Morbidity & Mortality
19, 3, p. 25-26.
Sverdrup, H. U., Johnson, M. W., Fleming, R. H. (1949).
The oceans, their physics, chemistry, and general
biology. Prentice-Hall, N. Y.
Swanson, V. E. (1972). Composition of coal, southwestern
United States - Tables of chemical analysis. USGS
Southwest energy study, Report of the Coal Resources
Work Group, Appendix J, Part II. USDI, Wash., D. C.
Takeuchi, T., Tawone, M., Kambara, I., Matsumoto, H.,
Morikawa, N., Murao, M., Hara, Y. (1957). Histo-
pathological studies of the encephalopathia from
unknown cause in Minamata district of Kyushu. J.
Kumamoto Med. Soc. (Suppl. 1) 3T, p. 37.
Tanner, J. T., Friedman, M. H., Lincoln, D. N. (1972).
Mercury content of common foods determined by
neutron activation analysis. Science 177, p.
1102-1103.
94
Truhaut, R. (1969). Second international symposium on
maximum allowable concentrations of toxic substances
in industrial environments. Arch. Environ. Health
19, p. 891-905.
Tunell, G. (1964). Chemical processes in the formation
of mercury ores and ores of mercury and antimony.
Geochim. Cosmochim. Acta 2_8, p. 1019-1037.
Turkenian, K. K., Wedepohl, K. H. (1961). Distribution
of the elements in some major units of the earth's
crust. Geol. Soc. Amer. Bull. 7_2, 2, p. 175-192.
Vinogradov, A. P. (1962). Average contents of chemical
elements in the principal types of igneous rocks of
the earth's crust. Geokhim. 7, p. 555-571. From
(Translation) Geokhim. 7, p. 641-663.
West, J. M. (1971). Mercury. From: Minerals Yearbook 2,
1969, p. 685-695. USDI, Wash., D. C.
Wickman, F. E. (1954). The total amount of sediments.
Geochim. Cosmochim. Acta 5, p. 97-110.
Williston, S. H. (1968). Mercury in the atmosphere.
Jour. Geophys. Res. 73^, 22, p. 7051-7055.
Wood, J. M., Kennedy, F. S., Rosen, C. G. (1968). Synthe
sis of methyl-mercury compounds by extracts of a
methanogenic bacterium. Nature 220, p. 163-174.
95

Linked assets

University of Southern California Dissertations and Theses

Conceptually similar

PDF

Early Diagenesis In Southern California Continental Borderland Sediments

PDF

Marine Geology Of The Baja California Continental Borderland, Mexico

PDF

Characterization of geochemical and lithologic variations in Milankovitch cycles: Green River Formation, Wyoming

PDF

Late-Neogene Paleomagnetic And Planktonic Zonation, Southeast Indian Ocean - Tasman Basin

PDF

Sedimentology And Pleistocene History Of Lake Tahoe, California - Nevada

PDF

Oceanography And Late-Quaternary Planktonic Foraminifera, Southwestern Indian Ocean

PDF

Heat Flow And Other Geophysical Studies In The Southern California Borderland

PDF

Recent And Upper Pleistocene Sediments Of The Southwestern Portion Of Losangeles County, California

PDF

Petrology And Depositional History Of Late-Precambrian - Cambrian Quartzites In The Eastern Mojave Desert, Southeastern California

PDF

Neogene to recent Naticidae (Mollusca : Gastropoda) of the eastern Pacific

PDF

A Study Of Human Response To California Library Organization And Management Systems

PDF

Distribution And Transport Of Suspended Matter, Santa Barbara Channel, California

PDF

The Aleutian-Kamchatka Trench Convergence: An Investigation Of Lithospheric Plate Interaction In The Light Of Modern Geotectonic Theory

PDF

Geochemical studies of beryllium isotopes in marine and continental natural water systems

PDF

Wave-Induced Scour Around Natural And Artificial Objects

PDF

Integrated geochemical and hydrodynamic modeling of San Diego Bay, California

PDF

Albert Camus And The Kingdom Of Nature

PDF

Ultrastructure Of Tests Of Some Recent Benthic Hyaline Foraminifera

PDF

Biogeography Of Lanternfishes (Family Myctophidae) South Of 30 Degrees S

PDF

Carbon isotopic heterogeneity and limited oxygen isotopic homogeneity in the cretaceous Cucamonga terrane, southeastern San Gabriel Mountains, California

Asset Metadata

Creator Hess, Frank Devereaux (author)

Core Title The Geochemical Cycle Of Mercury And The Pollutional Increment

Degree Doctor of Philosophy

Degree Program Geological Sciences

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag geochemistry,OAI-PMH Harvest

Language English

Contributor Digitized by ProQuest (provenance)

Advisor Bischoff, James L. (committee chair), [Chen, Kenneth S.] (committee member), Parks, George (committee member)

Permanent Link (DOI) https://doi.org/10.25549/usctheses-c18-732442

Unique identifier UC11356583

Identifier 7428442.pdf (filename),usctheses-c18-732442 (legacy record id)

Legacy Identifier 7428442.pdf

Dmrecord 732442

Document Type Dissertation

Rights Hess, Frank Devereaux

Type texts

Source University of Southern California (contributing entity), University of Southern California Dissertations and Theses (collection)

Access Conditions The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the au...

Repository Name University of Southern California Digital Library

Repository Location USC Digital Library, University of Southern California, University Park Campus, Los Angeles, California 90089, USA