660/3-74-012
Ecological Research Series
Heavy-Metal Accumulation
In Soil and Vegetation
From Smelter Emissions
National Environmental Research Center
Office of Research and Development
U.S. Environmental Protection Agency
Corvallis, Oregon 97330
-------
RESEARCH REPORTING SERIES
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been grouped into five series. These five broad
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2. Environmental Protection Technology
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This report has been assigned to the ECOLOGICAL
RESEARCH series. This series describes research
on the effects of pollution on humans, plant and
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-------
EPA-660/3-74-012
August 1974
HEAVY-METAL ACCUMULATION IN SOIL AND VEGETATION
FROM SMELTER EMISSIONS
Hi!man C. Ratsch
National Ecological Research Laboratory
Con/all is, Oregon 97330
Roap/Task 21BCI-01
Program Element 1AA006
NATIONAL ENVIRONMENTAL RESEARCH CENTER
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CORVALLIS, OREGON 97330
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price 80 cents
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ABSTRACT
Soil and plant samples were collected along north-south and northeast-
southwest transects radiating out from the Tacoma Smelter. The concen-
trations of lead, arSenic, cadmium and mercury in garden soil decline
with increasing distance from the smelter. The concentrations of arsenic
and cadmium in vegetation also decrease at increasing distance from the
smelter, but lead and mercury concentrations did not appear to be related
to distance from the smelter.
The heavy-metal levels in the samples demonstrate the accumulation
of large amounts of metals in surface soils and the availability of
metals to plants. When these values are compared to "average" heavy-
metal contents a deterioration of the quality of the soil and the presence
of heavy-metals at levels toxic to some plants is shown.
-------
CONTENTS
Page
Abstract ii
List of Figures iv
Sections
I Background 1
II Sampling and Site Evaluation 1
III Effects 3
IV Results 9
V Control Measures 10
VI Conclusions 11
VII Toxicity and Biogeochemistry
of Elements 12
VIII Tables of Heavy Metal Content 13
111
-------
FIGURES,
No. Page
la Arsenic Concentration in Vegetation 16
Ib Arsenic Concentration in Garden Soils 17
2a Mercury Concentration in Vegetation 18
2b Mercury Concentration in Garden Soils 19
3a Lead Concentration in Vegetation 20
3b Lead Concentration in Garden Soils 21
4a Cadmium Concentration in Vegetation 22
4b Cadmium Concentration in Garden Soils 23
IV
-------
Background
The Ruston copper smelter in Tacoma, Washington, has been a signifi-
cant source of air pollution during much of its 84 year history. The
emissions consist of SCL, SCL, acid mist and particulates of arsenic,
lead, zinc, cadmium, copper and sulfates. In 1970, the smelter was
discharging about a ton of particulate matter into the air each day,
containing as much as 590 Ibs. of lead and 876 Ibs. of arsenic. The
sulfur emissions amount to 200,000 tons per year.
There are two specific sources of emissions; (1) SO^j and partic-
ulates at a low level around the anode furnaces and plant operations,
and (2) S02, S03, acid mist and particulates from a tall stack (560
ft.). At present the smelter is functioning under intermittant controls
in which plant operations are shut down when S02 levels are expected to
exceed S02 air quality standards. During 1973, the plant reduced its
operations 25-30 percent.
Winds in the summer are from the north and northwest and carry
emissions from the smelter to residential and open areas in west Tacoma,
while during much of the fall, winter, and early spring the winds are
from the south and southwest and carry effluent to offshore islands
(Vashon and Muary Islands) in Puget Sound.
Sampling and Site Evaluation
In response to a request from EPA, Region X for assistance in
estimating the terrestrial impact of the smelter on the immediate area,
visits were made to the Tacoma smelter area to collect soil and vegetation
-------
samples. A total of 68 vegetation and soil samples were collected or
received from Puget Sound Air Pollution Control Agency from within six
miles of the Tacoma smelter. A majority of the samples were taken from
residential gardens on two transects (N-S, NE-SW) at varying intervals
from the smelter. The soil samples of the top 0-2 inches were taken
immediately adjacent to the vegetation samples. All the samples were
analyzed by the Consolidated Laboratory Services, NERC-Corvallis using
atomic absorption spectroscopy for lead, cadmium, zinc, copper and
antimony; flameless atomic absorption for mercury and the Silver Diethyldithio-
carbamate colorometric method for arsenic determination.
On August 2 and October 25th and 26th, 1973, site visits were made
in the vicinity of the smelter. The area within a mile south and south-
west of the smelter is striking in that only a few species of vegetation
remain with a complete absence of legumes (alfalfa, clover, etc.) and
Douglas fir. The species that predominate are maple, Oregon grape,
horsetail, laurel hedge, bracken fern, Scottish broom and native grasses.
At a greater distance from the smelter a larger variety of species is
observed, although Douglas fir is absent 4-5 miles southwest of the
smelter.
Vegetation injury reported over the years in the vicinity of the
smelter has been of the S02 and acid mist type. At the time of observation,
no S0? injury symptoms were observed on vegetation in the smelter vicinity.
Peach leaves showed some evidence of injury by acid mist, acid partic-
ulate or arsenic. At the Busic residence (5621 N. 46th ST.) margins of
peach leaves were red and showed small holes of necrotic tissue that
subsequently fell out of the leaf. Small bleached spots were seen
adjacent to the margins or covering the leaf. Marginal reddening of
-------
peach leaves followed by "shot hole," and then defoliation is indicative
of arsenic injury. Acid mist injures leaves by burning small holes in
the leaf tissue.
In general, plants reflect the geochemical environment in which
they grow. However, mineral elements differ in their availability to
plants and plant species differ in their ability to absorb specific
elements. Many factors determine the availability of a given element to
plants for example, relative abundance, form in which the element is
present, soil pH, interaction of elements, physical condition of the
soil, environmental factors of temperature and soil moisture and genetic
variability. Absorption of toxic metals through the leaf cuticle is a
significant source of contaminating in many species of plants.
Effects
A. Copper
The copper content of normal soils range from 1-200 ppm with most
in the range of 25-60 ppm. Normal plants contain from 5-20 ppm copper.
Copper has long been known to be toxic to plants. Levels in tissues
greater than 20 ppm, in general, are indicative of copper excess.
Excess copper commonly causes reduced growth and iron chlorosis symptoms
in plants and is associated with stunting, reduced branching, thickening
and abnormally dark coloration of rootlets of many plants. Clover,
alfalfa, poppy, spinach, gladious, corn, bean and squash are known to be
sensitive to copper.
The extremely high copper concentrations in grass and other leaf
sample from the smelter vicinity represent a possible environmental
hazard especially to sensitive plant species. These canot become
established and moderately sensitive species will show reduced growth.
-------
The absence of legumes in the smelter vicinity may be related to the
levels of copper and other metals in the soil.
B. Zinc
Total zinc in normal soils varies from 10-300 ppm and a wide range
of plants have concentrations of from 20-10,200 ppm. In a variety of
plants normal levels of zinc range from 25-150 ppm and amounts greater
than 400 ppm may indicate toxic levels of zinc.
The levels of zinc present in grass and leaves from the Tacoma
smelter appear to be within the high range of normal and probably are
not directly affecting plants, but may be important indirectly due to
interactions and competition with other heavy metals.
C. Cadmium
Cadmium is present in many soils and is apparently taken up with
ease by a great number of plant species, especially the grasses and
grains; for example, wheat, corn, rice, oats and millet. Cadmium is
also found in peas, beets, lettuce and radishes. The composition of an
"average" plant leaf is 0.5 - 0.6 ppm for cadmium and normal soils contain .06
ppm cadmium.
Cadmium is toxic to plants at higher concentrations. In radishes
grown in nutrient solutions at concentrations of 100 ppb cadmium, growth
of both roots and tops was reduced. At this level, the concentration
of cadmium in roots and leaves was 16.2 and 81.2 ppm respectively, but
no visible injury was evident.
In Japan, near a zinc refinery, the accumulation of cadmium was
extremely high in leaves of plants. Leafy vegetables such as greens,
cabbages, the leaves of eggplants, green onions and the leaves of radishes
4
-------
and turnips, contained 3.2 - 56 ppm cadmium. Greens with 56 ppm cadmium
were damaged.
Although the levels of cadmium in plant samples analyzed from the
Tacoma site are of questionable toxicity to plants, cadmium is present
in lettuce and cabbage in sufficient quantity to warrant toxicological
evaluations. Cadmium has been associated with a number of serious human
afflictions, e.g., hypertension, non-rheumatic heart disease, ostemalacia,
proteinuria and emphysema.
The values that are recommended or under discussion for maximum
allowable concentrations of cadmium in food is 135 micrograms per kilo-
gram (fresh weight) or approximately 1.35 parts per million (dry weight).
The cadmium levels in the cabbage family in the washed samples from
Tacoma ranged form 1.2 - 8.2 ppm (dry weight), with a mean value of 3.8
(dry weight), three to seven times higher than the maximum allowable
concentration.
D. Lead
Lead is present in all soils and plants. Soil contains an average
of 10-15 ppm and ranges from 2-200 ppm of lead.
In general, plants respond to lead only to a limited extent. For
example, the lead content of strawberries did not change when the lead
content of soil was increased from 8 to 59 ppm. In radishes a 10-fold
increase in soil lead content increased the lead concentration by a
factor of less than two.
The samples analyzed from Tacoma follow this pattern in that lead
values were essentially the same in cabbage cauliflower and brussel
sprouts regardless of the lead concentrations in the soil.
-------
Some plants showed retarded growth at 10 ppm lead in solution
culture studies. Lead reduced the growth of corn in nutrient solutions
and is translocated and accumulated in high concentrations in the leaves.
Foliar accumulation of lead was 3-8 times greater where phosphate was
deficient than were it was sufficent in the root environment. In young
corn leaves, 936 ppm of lead were found in the presence of adequate
phosphate while in phosphate deficient growth medium, the lead content
was 6,716 ppm.
E. Arsenic
The knowledge about the toxicity of arsenic is based on the use of
arsenicals over the years as insecticides, herbicides and defoliants.
Arsenic accumulates in soils to levels that may be phytotoxic. In
treated areas soils contain from 1.8 - 830 ppm arsenic, while untreated
areas had from 0.5 - 14.0 ppm arsenic.
In soils, toxic amounts of arsenic arrest the germination of seeds,
reduce the viability of seedlings and have the greatest effect at the
seedling stage. In soils the rate of nitrification in the presence of
arsenic is decreased and arsenic is toxic to nitrogen metabolism.
The concentration of soluble arsenic in soil necessary to cause
injury varies from 1 ppm for cowpeas, 9 ppm for peas and beans, 2 ppm
for barley, and 7 ppm for rice. Sodium arsenite applied to common field
sand at 1, 5 and 10 ppm reduced the yield of peas, beans, and corn.
Soil levels of 50-125 ppm of total arsenic may have a detrimental
effect on the growth of beans and strawberries. In apple orchards,
normal growth can be expected in soil with less than 50 ppm arsenic.
Soil with 50 - 100 ppm arsenic reduces growth 50 percent and soil with
over 100 ppm arsenic produces very little growth. Lead arsenate at 1-
200 pounds per acre reduced the germination of string beans and lima
beans and retarded the seedling growth of many vegetables. Apple seed-
6
-------
lings grown in potted soil with 100 - 160 ppm Sodium arsenate were
killed. Corn kernels rarely develop at soil concentrations of 80 - 100
ppm arsenic.
The chemical form of arsenic is more important than the total soil
arsenic in phytoxic effect. The formation of arsenic compounds is
affected by acidity, Fe, Al, Ca, P and humus content of the soil. Soils
with high reactive aluminum levels are less phytotoxic even after heavy
applications of arsenic. Six of the cabbage and lettuce samples from
Tacoma exceed the arsenic tolerance levels and are a possible health
hazard.
Arsenic is present in the soil and plant tissue from Tacoma at
levels that can be toxic to sensitive and moderately sensitive plant
species. Snap bean, lima bean, onion, peas, cucumber, alfalfa and other
legumes are highly sensitive to water soluble arsenic. This may account
for the fact that legumes are absent from the vicinity of the smelter.
F. Mercury
The mercury content of soils in the United States range from 10-500
ppb, and average 100 ppb. Mercury tends to be retained in the surface
layers of the soil due to adsorption by organic and inorganic materials
and the low solubilities of mercury salts (phosphate, carbonate, sulfide).
In most plants mercury concentrations range from 10-200 ppb (15 ppb
ave.), but plants growing near mercury deposits can contain 500-3500 ppb
mercury. Translocation of mercury occurs in many plant tissues, including
leaves, fruit and tubers.
Toxicity of mercury to terrestrial plants apparently depends more
on chemical form than on its concentration. There are but a few studies
available on the toxicity of mercury to specific plants, but small
7
-------
amounts of volatilized mercury are known to be toxic to roses in
greenhouses.
The mercury concentrations in the samples from Tacoma are well
above the "normal" mercury content. The values are on the threshold of
being a serious environmental hazard.
-------
Results
Sample locations and concentrations of heavy metals in garden soil
and vegetation are shown in eight Figures la-4b and Tables I-III. The
highest concentrations of lead, arsenic, cadmium, and mercury in the
soil were found close to the smelter. Generally, concentrations of
lead, arsenic, cadmium and mercury decline with increasing distance from
the smelter, although concentrations at points 1/4 - 1/2 mile from the
smelter stack are consistently lower than those at approximately 1/2 - 1
mile due to plume rise and looping at distances from the smelter.
The arsenic concentrations of plant samples follow the same pattern
as the soil samples in that the highest levels are found closest to the
smelter, and the values decrease at increasing distance from the smelter.
The lead and mercury present in vegetation samples did not appear to be
related to distance from the stack. The highest mercury concentration
in the plant sample was found 2 1/2 miles from the smelter. The lead
concentrations in vegetation samples did not differ significantly regard-
less of location, even though the soil lead concentrations varied widely.
The concentration of cadmium in vegetation samples is apparently unrelated
to the distance from the smelter. The cadmium concentrations are high
in plant samples relative to related soil samples, indicating that the
vegetation is actively accumulating cadmium from soils acidified by
sulfuric acid.
The high concentrations of sulfur in the grass samples indicate a
substantial sulfur enrichment of vegetation, although injury symptoms on
vegetation from sulfur were not observed. The expected sulfur content
of grass is 2000 - 4000 ppm.
-------
The analysis of vegetation and soil samples demonstrate the accumulation
of high concentrations of heavy metals in surface soils and the avail-
ability of these metals to plants. The heavy metal content of these
samples from the Tacoma sites are many times greater for the "average"
all elements analyzed with the possible exception of zinc. All of the
elements measured may be toxic to one or more plant species.
Control Measures
Methods of altering soil chemistry are available to minimize or
reduce heavy metal uptake by plants from soil. The addition of lime is
a common measure used to reduce metal uptake by
1. Decreasing the soil acidity to pH 6.5 may result in the precipitation
of heavy metals as hydroxides, carbonates, phosphates, etc., and in
immobilizing the heavy metal ions.
2. Cations will compete with the trace elements in the soil for
exchange sites of the soil and root surfaces.
3. Liming may promote the capacity of plant roots to form complexes
with metal ions.
Adding soil phosphates may be a means to precipitate heavy metals
as compounds of limited availability to plants.
10
-------
Conclusions
1. A major impact of the Tacoma smelter on the soil and vegetation
in the vicinity has been observed for many years. Sulfur dioxide emissions
over the years have degraded some plant species and altered the composi-
tion of plant communities. Heavy metals in soils in the smelter vicinity
have undoubtedly contributed to the degradation. With increased controls
on sulfur dioxide emissions, the heavy metals content in soil becomes more
important to soil toxicity and limits the restoration of natural plant
communities.
2. The heavy metals copper, arsenic and cadmium are present in
soils in concentrations that are likely to be toxic. These have suppressed
the establishment of natural and introduced plant species in contaminated
areas. Cadmium and mercury also represent a possible health hazard as
constituents of leafy vegetables.
3. Sulfur dioxide probably will have a lesser effect on vegetation
as emission controls increase. Plant injury due to high pollution
episodes should decrease and be replaced by low level chronic type
injury.
11
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General Classification of Toxicity of Elements to Plants /I
Very Toxic: Toxic effects may be seen at concentrations below 1 ppm
in nutrient solution (included are Cu++, Hg++, Pb++)
Moderately Toxic:
Scarcely Toxic:
Toxic effects appear at concentrations between 1 and 100
ppm in nutrient solution (included are AsIII, AsV, Cd++
Zn++)
Toxic effects rarely appear (included are C1-, I-, Ca++
K+)
II.
Arsenic
Cadmium
Copper
Mercury
Lead
Zinc
Sulfur
The Biogeochemistry of the Elements
(Bowen)/!
soils - 6 ppm
plants - 0.2 ppm
moderately toxic to plants
soils - .06 ppm
plants - 0.2 ppm
moderately toxic to all organisms
soils - 20 (2-100) ppm
plants - 14 ppm
very toxic to algae, fungi, seed
plants
(Chapman)/2
0.3-38 ppm
10-200 ppm
5-20 ppm
soils - .03-0.8 ppm
plants - .015 ppm
very toxic to fungi and green plants
soils - 10 ppm 2-200 ppm
plants - 100 ppm 25-150 ppm
very toxic to most plants
soils - 50 ppm 10-300 ppm
plants - 100 ppm 25-150 ppm
moderately toxic to most plants
30% 5 ppm or less
50% 5-10 ppm
20% 10 ppm or more
plants - 3400 ppm
1300-6500 ppm
Academic Press, London
I/ H. J. M. Bowen, Trace Elements in Biochemistry.
(1966)
2/ H. P. Chapman (Ed.) Diagnotic Criteria for Plants and Soils.
of California, Div. of Agricultural Sciences (1966)
University
12
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TABLE I
Heavy metal content of vegetation and soil samples from
the vicinity of the Tacoma Smelter. (Concentrations
expressed in parts-per-million on a dry weight basis)
Sample No.
7516001
7516002
7516003
7516004
7516005
7532001
7532002
7532003
7532004
7532005
7532006
7532007
7532008
Location
5020 Lexington St.
6102 Park Avenue
5309 Ruby Street
4852 N. 50th St.
5311 Commercial Ave.
Court & Baltimore
Court & Baltimore
5621 N. 46th St.
Sample
Arsenic Cadmium Lead
grass
grass
grass
grass
grass
grass
maple leaves
pear
horsebean pod
Ijigr^ib.ean
grape leaves
squash leaves
fig leaves
168
56.3
396
797
472
582
167
9
7
142
116
66
200
5
4
8
12
16
4
2
2
2
4
2
2
2
160
51
450
470
692
250
50
10
10
55
49
19
49
Mercury Zinc Copper Antimony Sulfur
2
2
8
8
10
3.0
1.3
0.3
0.4
2.5
1.8
1.9
1.3
381
49
208
288
190
113
113
49
12
180
50
140
48
608
350
2260
3040
3150
1400
1400
54
230
575
660
303
680
229
148
244
165
332
_
-
_
_
-
_
-
-
8090
9960
21900
13600
8000
-
-
-
-
-
_
-
-
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Table II
Heavy metal content of vegetation and spill samples from
the vicinity of the Tacoma Smelter. (Concentrations expressed
in parts-per-million on a dry weight basis)
Sample No.
7544016
7544034
7544017
7544035
7544018
7544036
7544037
7544038
7544039
7545004
7545001
7545005
7545002
7545006
7545003
7547001
7547002
7547003
7547004
Location
5621 N. 46th St.
969 Altadena Dr.
1719 Naomi PI.
(Seattle)
5141 N. Ruby St.
Manzanita Beach
Muary Island
Finer Point,
Muary Island
Neil! Point
Vashom Island
5130 N. 48th St.
5129 N. 47th St.
5140 N. 47th St.
Sample
Arsenic Cadmium Lead
soil
cabbage
soil
cabbage
soil
cabbage
soil
lettuce
(unwashed)
lettuce
(washed)
soil
broccoli i
soil
cabbage
soil
broccol 1 i
cabbage
214
11.4
12.2
1.5
7.3
1.8
457
no
68.5
36.2
12.5
36.8
3.1
39.1
10.9
1.6
(inner head)
brussel sprouts 30.8
saurkraut 0.6
cabbage 1.2
(inner head)
2.9
2.9
1.0
2.7
1.8
1.8
8.3
2.3
3.1
1.6
0.8
1.4
0.6
1.8
3.35
0.9
0.8
1.1
0.8
238
9
9
16
271
12
743
28
17
305
11
70
9
68
19
8
7
5
11
Mercury
11.0
0.5
0.
0.
,2
,7
0.2
0.3
6.8
1.0
1.2
0.6
0.5
0.2
0.2
0.3
0.6
0.1
0.1
0.06
0.1
14
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Table III
Heavy metal content of vegetation and soil samples from
the vicinity of the Tacoma Smelter. (Concentrations
expressed in parts-per-million on a dry weight basis)
Sample No
7542001
7542002
7542003
7542004
7542005
7544001
7544019
7544002
7544020
7544003
7544021
7544004
7544022
7544005
7544023
7544006
7544024
7544007
7544025
7544008
7544026
7544009
7544027
7544010
7544028
7544011
7544029
7544012
7544030
7544013
7544031
7544040
7544014
7544032
7544015
5129
5110
5618
2844
643
4845
3106
2136
5011
4508
8002
5130
5140
5423
5447
5103
St.
Location
N.
N.
N.
N.
Skyl
S.
N.
N.
N.
N.
W.
N.
N.
N.
N.
N.
47th St.
40th St.
43rd St.
Bristol
ine Dr.
7th St.
Huson St
Mildred
25th St.
Visscher
31st St.
48th St.
47th St.
49th St.
49th St.
Sample
lettuce
(unwashed)
lettuce
(washed)
cabbage
(unwashed)
cabbage
(washed)
soil
soil
brussel sprouts
soil
swiss chard
St. soil
cabbage
soil
brussel sprouts
soil
cabbage
soil
cauliflower
St. soil
cabbage
soil
cabbage
St soil
cabbage
soil
cauliflower
soil
brussel sprouts
soil
cabbage
soil
cabbage
cabbage
(unwashed)
soil
cabbage
Winnifred soil
Arsenic
657
445
94
67
384
44.
7.
331
27.
24.
5.
26.
4.
16.
1.
55.
5.
93.
8.
24.
8.
355
14.
29.
5.
110
16.
326
32.
240
79.
128
247
3.
307
2
8
6
0
2
4
6
5
0
7
5
3
5
6
7
5
7
2
3
9
2
45
Cadmium
1.
2.
n
5.
1.
8.
1.
5.
1.
3.
2.
2.
2.
7.
0.
5.
12.
2.
1.
2.
1.
1.
5.
5.
8.
6.
7.
7.
1.
7.
86
3
6
5
2
4
3
5
0
3
6
5
9
9
3
0
4
7
4
8
2
4
0
3
6
8
0
5
8
Lead
1200
700
50
45
1100
115
14
972
19
44
20
12
25
97
14
120
23
102
11
30
20
1190
22
52
21
88
11
505
16
291
9
65
819
14
1240
Mercury
6.
3.
0.
0.
3.
1.
0.
6.
0.
1.
0.
0.
0.
0.
0.
0.
0.
0.
2.
1.
0.
3.
0.
0.
0.
0.
0.
4.
0.
1.
0.
1.
3.
0.
3.
0
2
4
1
9
37
5
1
4
5
5
7
3
2
3
6
7
5
4
0
6
6
8
3
5
9
4
8
3
9
7
2
0
3
6
7544033
cauliflower
35.8
3.5
13
0.5
15
-------
Fig. la
Arsenic concentration (ppm) in vegetation
in the Tacoma area.
COMMENCEMENT
BAY
TACOMA
16
-------
Fig. lb
Arsenic concentration (ppm) in garden
soils in theTacoma area.
COMMENCEMENT
BAY
17
-------
Fig. 2a
Mercury concentration (ppm) in vegetation
in the Tacoma area.
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TACOMA
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Fig. 2b
Mercury concentration (ppm) in garden
soils in the Tacoma area.
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Scale of miles
TACOMA
19
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Fig. 3a
Lead concentration (ppm) in vegetation
in the Tacoma area.
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Fig. 3b
Lead concentration (ppm) in garden soils
in the Tacoma area.
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Fig. 4a
Cadmium concentration (ppm) in vegetation
in the Tacoma area.
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TACOMA
22
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Fig. 4b
Cadmium concentration (ppm) in garden
soils in the Tacoma area.
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Scale of miles
TACOMA
23
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BIBLIOGRAPHIC DATA
SHEET
1. Report No.
EPA-660/^-7^-012
3. Recipient's Accession No.
4. Title and Subtitle
Heavy*Metal Accumulation in Soil and Vegetation
from Smelter Emissions
5. Report Date
August 1974
6.
7. Author(s)
Mil man C. Ratsch
8- Performing Organization Kept.
No.
9. Performing Organization Name and Address
National Ecological Research Laboratory
Environmental Protection Agency
Con/all is, OR 97330
10. Project/Task/Work Unit No.
PE 1AA006 21 BCI-01
11. Contract/Grant No.
12. Sponsoring Organization Name and Address
same
13. Ty|3e of Report & Period
Covered
Final
14.
15. Supplementary Notes
16. Abstracts
Soil and plant samples were collected along north-south and northeast-southwest
transects radiating out from the Tacoma Smelter. The concentrations of lead, arsenic,
cadmium, and mercury in garden soil decline with increasing distance from the smelter.
The concentrations of arsenic and cadmium in vegetation also decrease at increasing
distance from the smelter, but lead and mercury concentrations did not appear to
be related to distance from the smelter. The heavy-metal levels in the samples
demonstrate the accumulation of large amounts of metals in surface soils and the
availability of metals to plants. When these values are compared to "average"
heavy-metal contents a deterioration of the quality of the soil and the presence-
of heavy metals at levels toxic to some plants is shown.
17. Key Words and Document Analysis. 17o. Descriptors
Heavy-metal accumulation
Air pollution
Vegetation effects
soil toxicity
copper smelter emissions
17b. Identifiers /Open-Ended Terms
heavy-metal accumulation in soils
heavy-metal accumulation in vegetation
air pollution
17c. COSATI Field/Group
18. Availability Statement
19. Security Class (This
Report)
UNCLASSIFIED
20. Security Class (This
' UNCLASSIFIED
21. No. of Pages
23
22. Price
FORM NTIS-35 (REV. 3-721
USCOMM-OC 14952-P72
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