STUDY OF LEAD, COPPER, ZINC AND CADMIUM
CONTAMINATION OF FOOD CHAINS OF MAN
C. Richard Dorn; Project Director
James 0. Pierce, II; Co-investigator
Gerald R. Chase; Co-investigator
Patrick E. Phillips; Research Associate
University of Missouri
Columbia, Missouri 65201
Contract Number 68-02-0092
Date: 6/26/71 to 12/26/72
Final Report
Prepared for the Environmental Protection Agency
Durham, North Carolina
December 1972
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TABLE OF CONTENTS
I . INTRODUCTION
II. SUMMARY
III. RECOMMENDATIONS
IV. MATERIALS AND METHODS
A. DESCRIPTION OF STUDY AREA
B. SELECTION OF THE TEST FARM
C. SELECTION OF THE CONTROL FARM
D. DESCRIPTION OF THE TEST AND CONTROL COWS
E. SAMPLE COLLECTION AND PREPARATION
F. ATOMIC ABSORPTION SPECTROPHOTOMETRY
PROCEDURES
6. STATISTICAL PROCEDURES
V. RESULTS AND DISCUSSION
A. DUSTFALL
B. SOIL
C. VEGETATION - ROOTS
D. VEGETATION - TOPS
E. CATTLE HAIR
F. CATTLE BLOOD
G. MILK FROM COWS
H. CATTLE TISSUES
I. HUMAN CONSUMPTION OF MEAT AND MILK FROM COWS
EXPOSED TO PRODUCTION SOURCES OF HEAVY METALS ..
J. GARDEN CROPS
K. LEAD TRANSLOCATION
PAGE
2
5
8
11
11
.... 13
14
17
19
25
26
33
33
34
35
35
37
38
39
76
76
80
80
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PAGE
L. INTAKE AND ASSIMILATION OF LEAD BY CATTLE 87
M. METEOROLOGICAL EFFECTS AND SOURCES OF
CONTAMINATION ON THE TEST FARM 94
VI. REFERENCES 103
VII. ACKNOWLEDGMENTS 108
VIII. APPENDIX TABLES 110
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I.
INTRODUCTION
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I. INTRODUCTION
Environmental contamination by cadmium (Cd), copper (Cu),
lead (Pb) and zinc (Zn) involves several trophic levels of the
ecosystem. It is well documented that airborne lead is translo-
cated through food chains of soil, roots, foliage and domestic
animals to man. Lead is present in varying amounts in all
natural foods. Cadmium is usually present in the environment in
small amounts, but serious illnesses in human and domestic animal
populations have been observed following ingestion of food and
2
water contaminated by cadmium containing mining wastes. Copper
and zinc are considered essential elements for mammals and are
3
translocated from the soil via various food chains.
Under normal circumstances, the levels of these elements
in the environment are determined by the geochemical composition
of the region, and they are not high enough to adversely affect
the health of indigenous animal or human populations. For example,
the current soil lead concentrations in most rural areas are
usually similar to the average content in the earth's crust,
a
10-15 ug/gm. There is, however, evidence that there have been
localized increases in lead concentrations in soil, and this is
thought to be associated with an increased body burden of lead
among certain population groups.
Lead ore mining and lead production results in the addition
of Cd, Cu, Pb and Zn to the levels naturally present in the soil.
The extent of this contamination depends upon the amounts contribu-
ted by various sources. In turn, the level of contamination will
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affect the quantities of these elements translocated in various
food chains. Some of the food chains involve human foods, and
environmental contaminants may be transported long distances in
food products. Thus, remote human populations may be exposed via
food products to contaminants originating in a mining area.
The primary purpose of this study was to investigate
production sources of heavy metal contamination of food supplies.
The objectives were:
1. estimation of annual contamination of soil in a lead
mining area by Cd, Cu, Pb and Zn,
2. quantisation of these metals on vegetation,
3. estimation of intake by animals grazing on contaminated
vegetation,
4. determination of levels of contamination of meat and
milk produced by cattle grazing on contaminated pasture.
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II.
SUMMARY
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II. SUMMARY
A statistically designed study was conducted In the new
lead producing region of southeastern Missouri to estimate the
amount of soil, vegetation, meat and milk contamination by Cd, Cu,
Pb and Zn. Dustfall, soil, root and vegetation tops were collected
4 times during a one year period at varying distances from the
highway on a test farm exposed to lead production sources of heavy
/
metal contamination and on a control farm outside the lead production
area. Hair, blood, milk, liver, kidney cortex, diaphragm muscle
and bone samples were collected for analysis by atomic absorption
spectrophotometry from cows.on the test and control farms. Between
the first and last sampling, the lead concentration In soil at the
60 ft (18,3 m), 140 ft (42,7 m) and 220 ft (67.1 m) sites on the
test farm Increased 219%, 257% and 284%, respectively. The main
sources of heavy metals at the test farm were stack emissions from
a lead smelter, lead ore concentrate spillage from trucks, and dust
from stockpiled ore at the smelter. High lead and cadmium dustfall
and air filter samples at the test farm corresponded to wind con-
ditions that would carry the smelter plume In the direction of the
test farm, located approximately 800 meters from the stack. The re-
sults of analyses of dustfall and soil samples from the 3 sites at
varying distances from the highway indicated that copper was a
highway contaminant on the test farm but not on the control farm.
The highest airborne, suspended Cd, Cu, Pb and Zn concentrations
were observed in winter on the test farm. This corresponded with
high dustfall, soil and vegetation levels and the time of greatest
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increase in lead assimilation by a project owned test cow.
There was a general dilution in the lead concentrations at each
step of the food chain from soil to cattle tissues on the control
farm, while on the test farm bio-magnification of lead in the
grass roots was observed. This was attributed to higher airborne
lead levels on the test farm, foliar absorption and deposition
in the roots. On an equivalent basis, the test cow's blood Pb
concentration at the end of the study period was 1/246 the test
farm soil concentration and the control cow's blood Pb was 1/187
the control farm soil concentration. Analysis of cattle hair was
a sensitive indicator of lead contamination; however, it had
limited use in determining the body burden of lead because washed
hair contains both exogenous and endogenous components. The liver,
kidney, muscle and milk of the test cow contained very small
amounts of cadmium, and the lead levels were 2.35 ug/gm, 3.75 ug/gm,
0.19 ug/gm and 13 ug/100 ml, respectively. The test cow milk Pb
concentrations were 1.9 times that of the control cow, and Pb
concentrations in milk from another cow exposed to only lead ore
concentrate spillage from trucks and background sources was
intermediate to those for the test and control cows.
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nr.
RECOMMENDATIONS
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III. RECOMMENDATIONS
The following recommendations are based on the results
of this study:
1. Lead ore concentrate should not be hauled by trucks
on public highways or property in open hoppers, or
without enough moisture to prevent escape of dust
in transit.
2. Dust from stockpiled lead ore concentrate and
metallurgical fumes in smelter emissions should be
controlled to as small amounts as possible.
3. Tolerances should be determined for lead and cadmium
in ambient air and continuous air sampling in lead
production areas should be conducted using standard
criteria.
4. It should be determined if slag, the end by-product
resulting from the smelting process, contains lead
which is available to plants and animals.
5. The use of slag in road maintenance should be dis-
couraged because feasible environmental monitoring
usually relies on testing soil or other environmental
samples, and current analytical methods can not
determine with reliability that portion of the total
lead that is taken up by plants.
6. Tolerances and/or guidelines should be developed for
permissible levels of lead and cadmium in meat and
milk products in the United States.
8
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7. A long term surveillance program should be developed
to monitor for build up of lead and cadmium In the
environment and possible harmful botanical and health
effects using soil, cattle hair and other biological
samples as markers.
8. Systems to identify sources of lead contamination
using lead isotopic ratios of selected food chains ,
involving domestic animals and wildlife in south-
eastern Missouri should be developed.
9. Long range plans for uses of National Forests, National
Parks and other public lands that involve industrial
leasing and development should include specific
tolerances and guidelines that will prevent the
occurrence of ecological imbalances.
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IV.
MATERIALS AND METHODS
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IV. MATERIALS AND METHODS
A. Description of Study Area
The area chosen for study was Iron and Reynolds Counties
in southeastern Missouri (Figure 1). Geological exploration
of this part of the State in the 1950's and early 1960's
indicated that major deposits of lead, zinc, copper and silver
were present. Since then extensive industrial development has
occurred, and it has become the world's largest lead-producing
district. In 1970 the production was 432,576 tons of lead
or 74.431 of the entire U.S. lead production. The location
of this new mining district has been named the "Viburnum Trend"
or "New Lead Belt" to distinguish it from the older lead
producing areas that are now inactive.
The development of new mines has been accompanied by the
building of two new lead smelters which became operational
in 1968. One smelter was built at a mining site in the
Clark National Forest, and the other was built on privately
owned land at Glover, Missouri. Following milling and con-
centration, lead ore is hauled by truck via State Highway
72/21 to the smelter at Glover from the mining sites in the
Clark National Forest to the west (Figure 1). This part of
the highway traverses wooded and agricultural land. The
deforested areas are used as pasture for livestock. The chief
agricultural products are hay, beef cattle and hogs. Dairy
cattle, horses and garden crops are also raised on a more
limited basis.
11
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FIGURE 1. A MAP OF IRON AND REYNOLDS COUNTIES IN SOUTHEASTERN MISSOURI
SHOWING ROADS, TEST AND CONTROL FARMS, VIBURNUM TREND, LEAD
MINES, AND SHELTERS, (MODIFIED FROM HAYES AND SEARIGHT, 1969)
+
VIBURNUM TREND
LEAD SMELTERS
LEAD MINES
o
L
10
20
'
30
MILES
12
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There are several ways in which heavy metals from the
lead producing operations enter the environment. The galena
(PbS) deposits are approximately 700-1200 feet deep so the
metallurgical dusts associated with removal of the ore and
milling are limited to the shaft sites. Excess water from
the mines and waste water containing tailings are directed
to settling and treatment lagoons which have varying effi-
ciencies in removal of heavy metals before discharge into
receiving streams in the area. Spillage of lead ore
concentrate, which is comprised of approximately 70.0% Pb,
1.5% Zn, 0.5% Cu and 0.2% Cd, from the trucks enroute to the
Glover smelter adds to the background levels along the
roadsides from automobile emissions and other sources. In '
the Glover area, especially downwind from the smelter, emissions
from the smelter stack and dust from stockpiled ore are
sources of contamination. Slag from the smelter, containing
approximately 2.5% Pb, is used as road resurfacing material
and, also, for road clearing in the winter.
B. Selection of the Test Farm
The selection of the test farm was based upon the
availability of cattle for testing and exposure to contamina-
tion from production sources of heavy metals. The farm chosen
was on the ore trucking highway (72/21) near Glover in Iron
County, approximately 800 meters (0.5 mile) north of the
smelter stack (Figure 1). During 1970, horses on this farm
and a farm on the opposite side of the highway developed signs
of lead poisoning and died.
13
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Selection of the Control Farm
The control farm was selected from the same geographical
region, with as many of the characteristics of the test farm
as possible except exposure to lead production sources of
contamination. Both the test and control farms have soil of
the Clarksville stony loam type, and they have similar topo-
graphic features. Results of macroelement, pH and organic
matter analyses of soil samples from each farm are presented
in Table 1. There was considerable variation between measure-
ments at the beginning and those at the end of the study.
This variation, partially due to variation 1n sample collection
and to crop depletion, was approximately as great as the
variation between farms. Therefore, the farms were relatively
similar in respect to macroelements, pH and organic matter.
The depletion of macroelements and organic matter and the
decline 1n pH from the beginning to the end of the study on
both farms is understandable in view of the absence of
fertilizer applications since 1970, absence of lime applica-
tions since 1969 (test farm) and 1966 (control farm), and
very little manure application.
Similar grasses were identified (Table 2) and the top
growth during 1972 was approximately 1.1 meters on both farms.
The amount of rainfall was approximately the same on both
farms during the study period (Table 3). The test and control
farms were also similar in regard to proximity of pastures to
the highway and farming practices. There was a negative
14
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Table 1. History of Fertilizer and Lime Applications and Results of Analyses of
Soil Samples from Test and Control Farms
N
P2°5
K
Ca
Mg
CaC03
pH
Organic matter
(percent)
Test Farm
Last fertilizer 116 116 116
application
(12-12-12 in 1970)
Last lime application
(red lime in 1969)
Soil test, Sep., 1971 58.0 380
Soil test, Oct., 1972 69.0 210
Control Farm
Last fertilizer 100 100 100
application
(12-12-12 in 1970)
Last lime application
(red lime in 1966)
Soil test, Sep., 1971 8.0 95
Soil test, Oct., 1972 50.0 480
3500
2200
600
420
5100 800
2700 460
8,000
6,000
6.2
4.9
6.3
5.8
5.1
4.5
6.5
4.1
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Table 2. Listing of Grasses In Pastures on Test and Control
Farms
Species
Poa annua
Tridens flavus
Lespedeza virginica
Trifollum repens
Trifolium pratense
Common
Name
Blue grass
Purple Top
Bush Clover
White Clover
Red Clover
Test
Farm
X
X
X
X
X
Control
Farm
X
X
X
Table 3. Rainfall Recorded on Test and Control Farms during
Study Period
Inches of Rainfall
Time
Total
Sep
Oct.
Jan .
Apr.
Jul.
Period
(Oct.
. 1972;
- Dec.
- Mar.
- Jun.
- Sep.
1
)
1
1
1
1
971 -
971
972
972
972
Test
33.
7.
4.
9.
12.
Farm
27
11
31
15
70
Contro
37.
9.
3.
12.
11.
1 Farm
33
07
45
96
85
16
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slope away from the roadway: approximately 1.5 meters per
50 on the test farm and approximately 6 meters per 50 on
the control farm.
A Highway Commission Survey conducted in 1970-71, indica-
ted that the traffic passing near the test farm was less than
that passing a point near the control farm (Table 4). Because
of the location of the counters and higher traffic volume near
town, the count near the test farm is probably an under-
estimate and the count near the control farm is probably an
overestimate of the volumes that actually pass the test and
control farms.
Description of the Test and Control Cows
The cows selected for study on the control farm will
be described first. The owner-operator of the control farm
had a 6 cow dairy herd which provided milk for the family's
use and for sale to the local neighbors. The cow that the
owner was willing to sell to the project (for slaughter at
the end of the study) was a purebred Holstein, 10 years of
age. A 10 year old half-sister of this cow, originally from
this herd, was purchased from a neighbor and used as a
genetically matched comparison cow on the test farm. The
youngest of the other cows in the control farm were chosen
as the remaining 3 of the required 4 cows to be studied.
They were a 3 year old Holstein, a 3 year old Guernsey and a
6 year old Guernsey-milking shorthorn crossbred cow. None of
these cows had been moved from the farms so they had never
been exposed to lead mining sources of heavy metals.
17
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Table 4. Vehicular Traffic by Season Near Test and Control
Farms
*
Number of Vehicles
Months
Oct.
Jan.
Apr.
Jul.
- Dec.
- Mar.
- Jun.
- Sep.
Test Farm
76077
58706
85107
96196
Control Farm
136260
114425
157202
177654
Factored average traffic volume for 1970-1971 from Missouri
State Highway Commission data.
Counter located on Route 21, .3 miles north of test farm.
+Counter located on Route 106, .3 miles west of Ellington
and 3.7 miles east of the control farm.
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The test farm was primarily a cow-calf operation with a
few pleasure horses for riding. At the initiation of the
study, the owner of the farm acquired 2 Hereford-dairy
crossbred cows with young calves and a Jersey cow with a
young calf. The crossbred cows were 3 years and 5 years of
age and the Jersey was approximately 7 years of age. The
fourth cow for study on the test farm was the half-sister
of the 10 year old Holstein on the control farmi The mean
ages were: 6.25 years for the test cows and 5.5 years for the
control cows. All of the cows studied on the test farm '
originally came from locations outside the new lead-belt area,
and they were placed on the test farm 1-2 weeks before the
first sample collection, October 2, 1971.
E. Sample Collection and Preparation
The main sampling was performed on a seasonal basis:
fall (Oct.-Dec.), winter (Jan.-Mar.), spring (Apr.-Jun.),
and summer (Jul.-Sep.). This sampling was performed in the
same manner on each farm on the same day or on contiguous
days. For dustfall, soil, roots and washed and unwashed
vegetation tops, 3 distances from the highway were used:
60 ft (18.3 m), 140 ft (42.7 m), and 220 ft (67.1 m). Two
rows of 3 sites each were established on each farm as shown
in the following site diagram:
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>*:
XI
u-
I-H!
aci
i i
Distance from highway
60 ft
140 ft
2
220 ft
Dustfall
buckets
1. Dustfall
Settleable particulates were collected In 5.6 liter
TM
polyethylene Tupperware canisters. These containers
were chosen because they are the standard equipment used
by the Missouri Air Conservation Commission and other
official agencies. The area of the mouth of the container
was 0.0284 square meters.
Paired dustfall containers were placed in a holder
approximately 1.7 meters above the ground at each of the
6 sampling sites on each farm. Use of both containers was
alternated between rows each sampling period to accomplish
50% duplicate sampling. In other words, at each sampling,
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9 dustfall containers were collected on each farm
(6 from one row and 3 from the other).
Each container was washed with 1% nitric acid and
deionized-distilled water 3 times in the field at the
time of placement at the site. The dustfall containers
were left at each site for approximately 3 months during
each sampling period. Ethylene glycol was added to the
containers during the winter months to avoid freezing
of contents and subsequent cracking of the container.
The contents of each container were emptied into
600 ml Pyrex beakers and, when required, reduced in
volume to about 150 ml by boiling. Each container was
scrubbed and rinsed with deionized-distilled water to
ensure complete removal of contents. Deionized-distilled
water was added to make 250 ml total; 25 ml were then
transferred to Kjeldahl flasks for wet ashing using a
hot acid mixture (5 parts nitric acid : 1 part perchloric
acid). The ash was then diluted to 25 ml with 1% nitric
acid and stored to await analysis by atomic absorption
spectrophotometry (AAS).
2. . Air filters
Suspended particles were collected on 2 inch diameter
glass fiber filters, Gelman Type E, with efficiency greater
than 985K for particles 0.05 microns or larger and a flow
rate of approximately 0.025 cubic meter per minute.
Collections were made for approximately one month during
each of the 4 sampling period at a single site on each farm,
21
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Each pump was calibrated before each new collection,
and the air flow during the collection period was
calculated. The filters were placed approximately
1.7 meters above the ground with an Inverted plastic
container mounted over the filter to protect against
rain and to avoid collecting large particles that would
fall directly on the filter, Clocks were wired into the
t
electrical supply for the air pumps and corrections were
made for periods that the electric power was off.
The exposed filter samples were leached using successive
amounts of hot acid mixture. Thirty ml of the acid mixture
was placed with the filter in a 250 ml beaker with a watch
glass cover and boiled for 2 hours. After cooling, the acid
was poured off and 30 ml of the acid mixture was added,
and the boiling was repeated. The supernatant was again
poured off, added to the original supernatant and reduced
to ash by heating in Kjeldahl flasks. The ash was then
diluted to 25 ml with 1% nitric acid and stored.
Soil
Four core samples of the top 15 cm of soil were
collected with a soil probe at locations A, B, C and D
shown in the site diagram. They were placed in a new
polyethylene bag, mixed and then passed through a 12 mesh
sieve to remove rocks. At each sampling, one or the other
row was alternately duplicated. After drying in an oven
at 105° C, a 3 gm portion was refluxed with 20 ml concen-
trated nitric acid in a 250 ml Pyrex beaker with a watch
22
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glass cover. The sample was then passed through a
Watman #42 filter and diluted to 100 ml with deionized-
distilled water after proper washing.
4. Vegetation-roots
Vegetation roots in 4 locations shown in the site
diagram (A, B, C and D) were exposed by a shovel, shaken
to remove excess dirt, scrubbed with a polyethylene brush
and water, and rinsed with deionized-distilied water.
The sample was then placed in tared polyethylene bags and
oven dried at 105° C. The dried sample in the bag was
then weighed; the weight of the bag was subtracted to
obtain the dried sample weight. The sample was then
placed in Kjeldahl flasks for wet ashing.
5. Vegetation - tops
Clump-size grass tops were cut 5 cm above the soil
at 4 locations (A, B, C and D) shown in the site diagram
and composited as one sample in polyethylene canisters
containing 200 ml deionized-disti1 led water. At each
sampling, one row or the other was alternately duplicated.
The tops were washed in the canisters, transferred to
polyethylene bags, oven-dried, weighed as for root samples,
and wet ashed. The washings were acidified to 1 N with
nitric acid, stored for 1-2 days, and filtered through
Watman #42 filter paper. The filtered samples were then
analyzed for the specific element. For unwashed vegetation
values, the washings and corresponding washed vegetation
values were added together.
23
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In addition, green bean, tomatoe and bell pepper
samples were collected from home gardens in the vicinity
of the test and control farms. They were washed, dried,
weighed and wet ashed as for the foliage. Their washings
were not analyzed.
Cattle hair
Approximately 10 gm of hair was clipped in equal amounts
from 4 different areas of the cow's body and then split
into duplicate samples in polyethylene bags. Each sample
was washed with 12 Snoop solution, a low trace metal
containing soap. The hair was then rinsed twice with
deionized-distilled water, air dried, and wet ashed.
Cattle blood and milk
Two 5 ml blood samples were collected by jugular
venipuncture in heparinized blood vials from each cow.
The samples were mixed gently to prevent clotting and
stored at 4° C.
Prior to collecting milk samples, the udder of the
cow was brushed to remove loose debris and the teats were
washed with water. The first milk (approximately 100-200 ml)
was discarded. Duplicate milk samples, consisting of
milk from each quarter, were collected in 100 ml glass
bottles and stored at 4° C.
Applied Laboratories, Inc.
24
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The 5 ml samples of blood and milk were added to 30
ml of acid mixture in Kjeldahl flasks for wet ashing.
Following cooling the sample was diluted with 1% nitric
acid to a final volume of 50 ml.
All of the blood and milk samples were extracted by
g
the following procedure, modified from Pierce and Cholak.
One-half ml perchloric acid and 2.0 ml ammonium citrate
solution were added to the samples. Ammonium hydroxide
or nitric acid was used to adjust the pH to 4.5. After
transfer to a 50 ml volumetric flask, 2.0 ml ammonium
pyrrolidine dithiocarbamate and 4.0 ml methyl isobutyl
ketone, were added to the flask. The organic layer which
forms is used for the atomic absorption analysis.
8. Cattle tissues
Five gm specimens of diaphragm muscle, bone, liver
and kidney cortex were collected at slaughter of one
cow from the test farm and one cow from the control
farm. These samples were stored at 4° C and then wet
ashed as previously described.
Atomic Absorption Spectrophotometry Procedures
The operation of the AAS followed previously described
procedures. All determinations were made by direct
aspiration of the sample solution or the extract into the
flame of the atomic absorption unit. Analysis of standards,
made according to sample concentration ranges, accompanied
each group of samples tested. The concentrations of elements
25
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under study were determined in blood vial, ethylene glycol and
glass fiber filter blanks (Table 5). All of the measurements
were low except for the zinc content in the glass fiber filters.
The mean filter blank zinc concentration (581 ug/gm) was
subtracted from the sample measurements to obtain corrected
values which were used in reporting the results. All values
are expressed on a dry weight basis except for blood, milk,
muscle, liver, kidney corte* and bone which are on a fresh
weight basis. The minimum detectable limits for specific
types of samples and elements are presented in Table 6.
Statistical Procedures
All samples were coded prior to submitting them to the
laboratory so that the laboratory personnel had no knowledge
of the study design considerations in the sampling. The
identifying information for each sample and the concentration
values were coded and placed on punch cards for statistical
analysis. All data were normalized by log transformation to
satisfy necessary assumptions for analysis of variance (ANOVA).
ANOVA was performed to determine the effect of farm location,
season and sampling site upon the concentrations of Cd, Cu,
Pb and Zn in the various components of the food chain under
study.
The ANOVA model for dustfall, soil and vegetation was:
Mijkl ' u + Ti + Pj + TPij + Dk + DTik + DPjk + DTPijk + Mijkl
where:
u represents some overall element measurement in ug/gm
epresents the
ment: i =1,4
T. represents the effect of the i time period on the measure-
26
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Table 5. Concentrations of Cd, Cu, Pb and Zn in Blood Vials,
Ethylene Glycol and Glass Fiber Filters
Element (ug/gm)
Blanks Cd Cu Pb Zn
Blood vials <.01 <.01 <.01 1.04
Ethylene glycol <.10 <.10 <.08 <.10
Glass fiber filters<.25 .65 <2.50 581
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Table 6. MINIMUM DETECTABLE LIMITS BY TYPE OF SAMPLE AND ELEMENT
Code No.
Type of
Sample
Element
Minimum
Detectable Limit
1 Air Sample Filter Cd 0.50 ug
4 Dustfall Cd 2.5 ug
5 Soil Cd 0.35 ug/gm
6 Roots (washed) Cd 0.50 ug/gm
Pb 5.0 ug/gm
7 Tops (washed) Cd 0.50 ug/gm
Pb 5.0 ug/gm
*
8 Tops (unwashed) Cd 1.5 ug/gm
*
Cu 1.0 ug/gm
*
Pb 15.0 ug/gm
9 Blood Cd 0.2 ug/100 ml
Pb 2'.0 ug/100 ml
10 Milk Cd 0.2 ug/100 ml
Cu 7.0 ug/100 ml
Pb 2.0 ug/100 ml
11 Hair Cd 0.01 ug/gm
12 Muscle Cd 0.10 ug/gm
13 Bone Cd 0.05 ug/gm
17 Water Cd 0.01 mg/1
Cu 0.01 mg/1
Pb 0.005 mg/1
Zn 0.01 mg/1
18 Grain Feed Cd 0.50 ug/gm
Pb 5.0 ug/gm
19 Hay or Silage Cd 0.50 ug/gm
Pb 5.0 ug/gm
21 Home-grown Vegetables. ... Cd 0.50 ug/gm
Pb 5.0 ug/gm
*If both washed tops and washings were below minimum detectable limits.
28
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P. represents the effect of the J farm on the measurement:
j
J - 1. 2
TP.. represents the effect on the ij time period-farm
J
combination on the measurement
D. represents the effect of k distance (site) from the
highway: k = 1 , 3
DTik represents the effect of the ik time period-distance
combination on the measurement
DP., represents the effect of the jk farm-distance combination
on the measurement
DTP... represents the effect of the ijk time period-farm-
1 J K
distance combination on the measurement
Miikl rePresents tne err°r term: 1=1,3
W'ikl rePresents ug/gm of a specific element in dustfall, soil,
roots, unwashed vegetation tops and washed vegetation tops
The conventional 5% level (p=0.05) significance was used
in interpreting the results. The p values are expressed to
the fourth decimal, although an individual value may have
little meaning beyond the second decimal because of the
approximations involved in the statistical analysis. Because
of the large number of comparisons and statistical tests per-
formed, it should also be recognized that even if no effects
were present, some differences may be statistically significant
due to chance alone.
The ANOVA model for hair, blood, milk, muscle and bone was:
Xijkl ' u + Ti + Pj + TPij + Ck(j) + CTik(j) + M
where:
29
-------
u represents some overall element measurement in ug/gm
T. represents the effect of the i time period on the
measurement: i = 1 , 4
P. represents the effect of the j farm on the measurement:
j = 1, 2
TP.. represents the effect of the ij time period-farm
' J
combination on the measurement
Ck/.\ represents the effect of the k cow on the j farm
on the measurement k = 1 , 4
CT.. /.\ represents the effect of the ik time period-cow
combination of the j farm on the measurement
Mik(i)l rePresents tne error term: 1=1,2
Xiikl rePresents u9/9m of a specific element in blood, hair
milk, muscle or bone.
For the tabular presentations of mean concentrations of
a specific element, individual values below the lower detectable
limit for that element and type of sample (Table 6) were
excluded, except for unwashed samples of vegetation tops. In
the analysis of variance calculations, the maximum values were
used for samples that contained a smaller concentration than
the lower detectable limit. For example, the cadmium value of
0.35 ug/gm was used for soil samples containing less than the
lower detectable limit. This has the result of avoiding assump-
tions of the exact values for those lower than the detection
limit. The control farm samples were more often below lower
detection limits than test farm samples; therefore, some
30
-------
comparisons between test and control farm samples are
conservative.
31
-------
V.
RESULTS AND DISCUSSION
-------
V. RESULTS AND DISCUSSION
A summary of variables with significant effects on heavy
metal concentration in the various food chain components studied
is presented in Table 7. Results of analyses of each component
will first be reported and then inter-relationships will be
considered.
A. Dustfall
The dustfall concentrations of all 4 elements (Cd, Cu, Pb
and Zn) were significantly different on the test and control
farms (Tables 8-11). The test farm to control farm ratios for
each element were: cadmium 11.9, copper 5.9, lead 12.9, and
zinc 6.8. Cadmium and zinc concentrations in dustfall varied
significantly between seasons. The winter season dustfall
samples from the test farm had the highest levels of Cd, Cu
and Pb; Zn was highest in the summer. The results indicated
that distance from the highway was a significant effect in the
Cu and Zn analyses. Copper was in highest concentration at
the 140 ft site on the control farm during all seasons, while
on the test farm there was a gradient of copper levels from
a high at the 60 ft site to a low at the 220 ft site in all
seasons except fall (Appendix Tables 1-8). An extremely high
2
lead dustfall measurement (170.3140 mg/m /mo) was obtained
at the 60 ft site on the test farm in the winter (Appendix
Table 3). There was a significant interaction of farm and
season in the cadmium analysis.
33
-------
B. Soil
The soils of the test farm and of the control farm
significantly differed in their concentrations of each of
the elements studied: Cd, Cu, Pb and Zn (Tables 12-15).
In each comparison, the concentration was greater on the
test farm than on the control farm. This was found for
Zn even though the fall Zn concentration on the control farm
was much higher than that on the test farm. From these fall
data (Appendix Tables 1-2) it was apparent that an aberrant
source of Zn was present and further examination of the data
revealed that a 60 ft site near a galvanized fence yielded
high Zn levels in soil, as well as in roots and vegetation
tops. All subsequent samples were collected at distances
greater than 6 feet from the fence.
There was significant seasonal variability in the concen-
trations of Cd, Cu and Pb in soil. The soil lead concentra-
tions increased over 2 fold during the study period on the
test farm.
The distance from the highway also had a significant
effect on the soil concentration of all 4 elements. For each
element, there was a gradient from high values at the 60 ft
site to lower values at the 220 ft site, except for unexplained
high levels of copper at the 140 ft site on the control farm
in all 4 seasonal samples (Appendix Tables 2, 4, 6 and 8).
These differences in copper levels in soil corresponded to the
copper levels in dustfall and indicated that copper was a
34
-------
highway contaminant on the test farm but not on the control
farm.
There were significant farm-season interactions for Cd,
Pb and Zn measurements which may reflect in part the seasonally
determined meterological effects on the distribution of smelter
stack emissions at the test farm. Farm and site interactions
were significant in Cd, Cu and Pb analyses. This was expected
in view of the multiple sources of highway contamination on
the test farm compared with only vehicular exhaust emissions
as a main source on the control farm.
C. Vegetation - roots
The Cd, Cu, Pb and Zn concentrations in roots all differed
significantly on the test and control farms (Tables 16-19).
There was also a significant effect of season on the concen-
trations of all 4 elements. Only Pb and Zn were significantly
affected by distance from the highway. An extremely high mean
zinc concentration (259.33 ug/gm) in 3 root samples from the
60 ft site at the control farm in the fall, was attributed to
the galvanized fence (Appendix Table 2). While the cadmium in
soil ratio on test and control farms was approximately 1:1, the
comparable cadmium in root ratio was approximately 3:1. The
lead in soil ratio was similarly smaller than the lead in root
ratio on test and control farms (5:1 vs. 12:1).
D. Vegetation - tops
The differences between the test and control farms'concen-
trations of all 4 elements, Cd, Cu, Pb and Zn, in unwashed
vegetation tops were significant (Tables 20-23). The largest
differences were for Cd and Pb. Lead in unwashed tops on
35
-------
the test farm was approximately 19.6 times higher than on the
control farm and cadmium was approximately 3.6 times higher
than on the control farm. All 4 elements also differed
significantly from season to season. The zinc variability
in unwashed tops is again probably due to sample collection
near the galvanized fence, as the extremely high mean value
of 337.37 ug/gm was obtained in the fall on the control farm
(Appendix Table 2). On the test farm, winter and spring were
consistently higher than summer and fall. High concentrations
of heavy metals in foliage during winter periods when plants
13-14
are dormant have been observed in several other studies.
The spring sample was collected on April 1 when the grass was
growing again, but before the extensive growth and grazing
which followed. In general, the pasture was grazed so that
most grasses did not grow higher than 60 cm, except where the
cattle were restricted and the grass grew to 1.1 meters.
Only zinc concentrations in unwashed tops were significantly
different on test and control farms. An inspection of the
data again implicated the samples, collected near the fence, that
contributed the high values. Farm-season interaction was sig-
nificant for all 4 elements. The higher contamination from
multiple sources at the test farm, linked with the seasonal
effect of dormant plants having higher concentrations than
rapidly growing plants, could explain this interaction.
The levels of all 4 elements in washed tops varied sig-
nificantly between test and control farms (Tables 24-27). All
elements except zinc were found in much higher amounts on the
36
-------
test farm than on the control farm. The high zinc levels
along the fence on the control farm again appeared to affect
the levels in the washed vegetation. Also, the significant
farm-site interaction reflects this unique exposure on the
control farm. The elemental concentrations in washed tops
were uniformly affected by seasons. Most of this effect was
present on the test farm where all 4 elements were highest
in tops during the winter and spring test periods. The site
variable was not significant for any element tested in washed
tops. The only significant interaction, farm and season,
could be explained by the unique exposure to smelter and
trucking contamination by Cd, Cu and Pb on the test farm and
to galvanized fence contamination by Zn on the control farm.
Cattle Hair
The concentrations of Cd and Pb in the washed hair of the
4 cows on the test farm were significantly different than the
concentrations in hair of the 4 control cows (Tables 28 and 30).
At the summer sampling the Cd concentration in the project
owned test cow's hair was approximately 10 times higher than
that of the project owned control cow's hair, and the Pb
concentration in the test cow's hair was approximately 115 times
higher than that of the control cow's hair (Appendix Tables
7-8).
The hair concentrations of three elements, Cd, Pb and Zn,
were significantly affected by season (Tables 28, 30-31). Only
Cu and Zn hair concentrations varied significantly among the
37
-------
cows on each farm (Tables 29 and 31).
Even though the hair was washed, apparently It is possible
that cadmium and lead adsorbed by hair remains in hair after
the washing process. Nishujama reported that cadmium and lead
adsorbed on human and mouse hair was incompletely removed by
different treatments. The most complete removal of cadmium
was by using a sufficiently strong solution of an acid; however,
the different treatments were not effective for separate
analysis of exogenous and endogenous cadmium in hair.
Therefore, analysis of hair concentrations of cadmium and
lead may not truly represent body accumulation, depending upon
the amount of airborne exposure. In the present study
airborne exposure was negligible on the control farm and
uniformly high on the test farm. The higher hair cadmium and
lead concentrations on the test farm than those on the control
farm, therefore, may reflect both the increased lead and
cadmium assimilation by the cattle and the adsorption of
airborne cadmium and lead on the hair. In any event, the high
hair concentrations of both elements truly reflected high
airborne concentrations on the test farm. That hair lead
concentrations were higher than the concentrations of any of
the other biological samples tested (Figure 4), supports the use
of cattle hair as a sensitive indicator of airborne lead
contamination.
p. Cattle Blood
The cows' blood Pb and Cu concentrations were both
significantly different on the test and control farms (Tables
38
-------
33-34). The mean of the blood lead concentrations of the
test cows was approximately 4 times greater than the cor-
responding mean value for the control cows. The difference
between blood copper concentrations of test and control cows
was in the opposite direction, i.e. the control cows were
higher than the test cows.
Blood concentrations of Cd, Cu and Pb for test and (
control cows were significantly affected by season (Tables
32-34). The only significant variability detected among
cows, within farm, was detected for blood zinc concentrations
(Table 35).
The highest concentration of blood lead was a mean of
87 ug/100 ml for 2 duplicate analyses of a spring blood sample
collected from the youngest (3 year old) cow on the test farm
(Appendix Table 5). The relationship between blood lead and
hair lead for the test cows is shown in Figure 2.
Milk from Cows
Lead was the only element studied that was significantly
affected by season and the only one present in significantly
different concentrations in milk from test and control cows
(Tables 36-39). The lead concentration was over 5 times
higher in milk from the project owned test cow than milk from
the project owned control cow. The highest concentration of
milk Pb was a mean of 35 ug/100 ml for 2 duplicate analyses
performed on a sample collected April 1 (spring) from the 7
year old cow on the test farm. As found for hair and blood,
39
-------
the concentrations of cadmium varied significantly among cows
on each farm.
There was significant interaction between farm and season
variables in the lead analysis. The winter and spring milk
lead concentrations were over 5 times the fall and summer
concentrations on the test farm only. The relationship
between milk Pb and blood Pb for the test cows is shown in
Figure 3.
40
-------
Table 7. Summary of Farm Location (F), Season (S), Gradient
Distance from Highway (D) and Cow Within Farm (C)
Variables With Significant Effect on Heavy Metal
Concentrations in Each Type of Environmental Sample
Type of Sample
Dustfall
Soil
Roots
Unwashed tops
Washed tops
Hair
Blood
Milk
Cadmium
F,
F,
F,
F,
F,
F,
S
S
S, D
S
S
S
S
Copper
F,
F,
F,
F.
F,
C
F,
C
D
S, D
S
S
S
S
Lead
F
F,
F,
F,
F,
F,
F,
F,
S, D
S, D
S
S
S
S
S
Zinc
F,
F,
F,
F,
F,
S,
C
S, D
D
i
S, D
S, D
S
C
Statistically significant at the 5% level
41
-------
Table 8. Summary of Data and Analysis of Variance for Cadmium In Dustfall
Test Farm Control Farm
No. of nean No. of
** , 2 **
Season Samples (mg/m /mo) Samples
Fall
Winter
Spring
Summer
8 0.7484 7
9 1.6617 1
8+ 0.5439 9
9 1.3913 2
Mean
2
(mg/m /mo)
0.2427
0.0386
0.0528
0.0322
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 452.619 107.981
3 41.481 3.299
2 1.207 0.144
2 60.868 7.261
2 1.900 0.227
6 24.044 0.956
4 10.728 0.640
50 209.583
P
.0001
.0272
.8665
.0021
.8005
.5346
.6395
**
Samples below lower detectable limit (2.5 ug) excluded; analysis of
variance based on maximum values for sample tests that were below
lower detectable limit.
*0ne sample lost in laboratory preparation.
42
-------
Table 9. Summary of Data and Analysis of Variance for Copper in Dustfall
Test Farm Control Farm
No. of Mean No. of
Season Samples (mg/m2/mo) Samples
Fall
Winter
Spring
Summer
9 2.2155 9
9 2.7543 9
8** 2.2300 9
9 1.9682 9
Mean
(mg/m2/mo)
0.7602
0.1983
0.3332
0.2515
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 75.003 216.688
3 0.817 0.787
2 2.408 3.479
2 0.212 0.306
2 0.960 1.387
6 1.834 0.883
4 0.625 0.452
50 17.307
P
.0001
.5097
.0374
.7419
.2582
.5152
.7730
**
One sample lost in laboratory preparation.
43
-------
Table 10. Summary of Data and Analysis of Variance for Lead in Dustfall
Test Farm Control Farm
No. of Mean No. of Mean
Season Samples (mq/mz/mo) Samples (mg/mz/mo)
Fall
Winter
Spring
Summer
9 97.6796
9 141.4106
8** 86.0278
9 96.4958
9 25.9181
9 2.1435
9 2.8856
9 1.7206
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares
1 218.296
3 7.701
2 0.668
2 0.538
2 1 .026
6 5.558
4 0.725
50 67.398
' F p
161.944 .0001
1.904 .1396
0.248 .7844
0.200 .8214
0.381 .6908
0.687 .6628
0.135 .9661
**
One sample lost in laboratory preparation.
44
-------
Table 11. Summary of Data and Analysis of Variance for Zinc in Dustfall
Test Farm
Control Farm
No. of Mean No. of
Season Samples (mg/m'/mo) Samples
Fall
Winter
Spring
Summer
9
9
**
8
9
1.4479 9
14.4001 9
12.3750 9
16.2486 9
Mean
(mg/mz/mo)
1.8170
1.2800
1.8486
1.5559
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
d.f.
1
3
2
2
2
6
4
50
Sum of
Squares F
47.299 444.499
36.504 114.349
0.975 4.582
0.497 2.335
0.240 1.130
0.622 0.974
0.100 0.234
5.321
P
.0001
.0001
.0147
.1053
.3316
.5464
.9164
**
One sample lost in laboratory preparation.
45
-------
Table 12. Summary of Data and Analysis of Variance for Cadmium In Soil
Test Farm
Control Farm
No. of Mean No. of **
Season Samples ( (ug/gm) Samples
Fall
Winter
Spring
Summer
Source
Farm
Season
Site
Farm* Sea son
Farm*S1te
Sea son* Site
Farm*Season*S1te
Residual (error)
9
9
9
9
Analysi
d.f.
1
3
2
3
2
6
6
48
.56 9
.91 9
.70 1
.83 1
s of Variance
Sum of
Squares F
5.399 342.001
2.039 43.055
0.126 4.006
0.745 15.721
0.118 3.736
0.105 1.109
0.093 0.982
0.758
Mean
(ug/gm)
.40
.60
.57
.37
P
..0001
.0001
.0240
.0001
.0302
.3711
.5511
**
Samples below lower detectable limit (0.35 ug/gm) excluded; analysis of
variance based on maximum values (0.35 ug/gm) for sample tests that
were below lower detectable limit.
46
-------
Table 13. Summary of Data and Analysis of Variance for Copper In Soil
Test Farm
Control Farm
No. of
Season Samples
Fall
Winter
Spring
Summer
9
9
9
9
Mean No. of
(ug/gm) Samples
9.86 9
12.01 9
12.76 9
12.26 9
Mean
(ug/gm)
5.71
7.58
7.82
6.50
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1
3
2
3
2
6
6
48
5.039 273.746
0.837 15.160
0.334 9.071
0.088 1.599
0.376 10.204
0.034 0.310
0.171 1.545
0.884
P
.0001
.0001
.0007
.2008
.0004
.9282
.1836
47
-------
Table
Summary of Data and Analysis of Variance for Lead In Soil
Test Farm
Control Farm
Season
Fall
Winter
Spring
Summer
No. of
Samples
9
9
9
9
Mean
(ug/gm)
52.00
77.83
88.62
128.28
No. of
Samples
9
9
9
9
Mean
(ug/gm)
13.00
15.13
18.87.
15.93
Analysis of Variance
' Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares
1
3
2
3
2
6
6
48
45.205
3.743
1.291
1.551
0.681
0.337
0.435
55.426
F
836.47
23.09
11.95
9.57
6.300
1.040
1.342
P
.0001
.0001
.0002
.0001
.0040
.4120
.2570
48
-------
Table 15. Summary of Data and Analysis of Variance for Zinc in Soil
Test Farm
Control Farm
Samples
Fall
Winter
Spring
Summer
No. of
Samples
9
9
9
9
Mean
(ug/gm)
24.11
30.24
33.16
33.24
No. of
Samples
9
9
9
9
Mean
(ug/gm)
30.56
22.16
23.89
15.69
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
d.f.
1
3
2
3
2
6
6
48
Sum of
Squares
1.727
0.447
1.319
1.605
0.221
0.299
0.961
3.053
F
27.153
2.344
10.368
8.410
1.740
0.784
2.518
P
.0001
.0836
.0004
.0003
.1848
.5884
.0333
49
-------
Table 16. Summary of Data and Analysis of Variance for Cadmium In Roots
Test Farm
Control Farm
No. of Mean No. of **
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 1.54 8
9 3.13 9
9 2.87 8
9 1.60 8
Mean
(ug/gm)
.92
.65
.69
.72
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 20.742 198.650
3 1.301 4.155
2 0.056 0.267
3 3.224 10.293
2 0.221 1.059
6 0.859 1.371
6 0.785 1.254
48 5.012
P
.0001
.0108
.7699
.0001
.3559
.2447
.2958
**
Sample below lower detectable limit (0.50 ug/gm) excluded; analysis of
variance based on maximum values (0.50 ug/gm) for sample tests that
were below lower detectable limit.
50
-------
Table 17. Summary of Data and Analysis of Variance for Copper In Roots
Test Farm
Control Farm
No. of
Season Samples
Fall
Winter
Spring
Summer
9
9
9
9
Mean No. of
(uq/qm) Samples
21.89 9
33.88 9
24.28 9
17.49 9
Mean
(uq/qm)
11.32
20.69
15.71
11.62
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1
3
2
3
2
6
6
48
4.325 84.378
4.197 27.291
0.057 0.559
0.163 1.063
0.387 3.779
0.105 0.340
0.580 1.886
2.460
P
.0001
.0001
.5808
.3745
.0291
.9117
.1021
51
-------
Table 18. Summary of Data and Analysis of Variance for Lead in Roots
Test Farm
Control Farm
No. of Mean No. of **
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 208.22 9
9 238.67 8
9 309.00 9
9 132.11 8
Mean
(ug/gm)
12.73
8.74
22.33
10.53
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 139.849 606.494
3 6.091 8.805
2 1.594 3.456
3 1.886 2.726
2 1.632 3.539
6 1.628 1.177
6 1.877 1.356
48 11.068
P
.0001
.0002
.0385
.0534
.0358
.3341
.2507
**
Sample below lower detectable limit (5.0 ug/gm) excluded; analysis of
variance based on maximum values (5.0 ug/gm) for sample tests that
were below lower detectable limit.
52
-------
Table 19. Summary of Data and Analysis of Variance for Zinc in Roots
Test Farm
Control Farm
No. of
Season Samples
Fall
Winter
Spring
Summer
9
9
9
9
Mean No. of
(ug/gm) Samples
79.89 9
100.78 9
84.44 9
57.89 9
Mean
(ug/gm)
124.56
45.56
38.17
54.61
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*S1te
Residual (error)
Sum of
d.f. Squares F
1
3
2
3
2
6
6
48
2.583 15.332
1.940 3.839
4.318 12.817
2.518 4.983
0.310 0.921
2.504 2.478
1.795 1.776
8.085
P
.0005
.0151
.0001
.0046
.5924
.0357
.1236
53
-------
Table 20. Summary of Data and Analysis of Variance for Cadmium in
Vegetation (unwashed)
Test Farm
No. of ** Mean
Control Farm
No. of ** Mean
Season
Fa\l
Winter
Spring
Summer
Samples (ug/gm) Samples
9 3.60 9
9 8.41 9
9 8.72 9
8* 2.03 9
(ug/qm)
1.74
1.55
1.50
1.52
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Sguares F
1 21.238 311.081
3 5.816 28.396
2 0.121 0.885
3 6.494 31.708
2 0.091 0.664
6 0.488 1.192
6 0.303 0.739
47 3.209
P
.0001
.0001
.5777
.0001
.5239
.3265
.6227
**
For calculation of means and analysis of variance, minimum detectable
limit values (0.50 ug/gm for washed vegetation; 1.00 ug/gm for washings)
were used for measurements below these limits.
''One sample lost.
54
-------
Table 21
Summary of Data and Analysis of Variance for Copper In
Vegetation (unwashed)
Test Farm
Control Farm
No. of ** Mean No. of **
Season Samples (ug/qm) Samples
Fall
Winter
Spring
Summer
9 12.63
9 19.67
9 17.84
8+ 6.71
9
9
9
9
Mean
(ug/gm)
11.85
9.42
7.08
5.78
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*S1te
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares
1 4.116
3 5.684
2 0.123
3 2.154
2 0.316
6 0.116
6 0.215
47 2.553
F
75.783
34.886
1.129
13.221
2.906
0.357
0.659
P
.0001
.0001
.3326
.0001
.0630
.9021
.6845
**
For calculation of means and analysis of variance the minimum detec-
table limit value for washings (1.00 ug/gm) was used for sample
measurements below this limit.
One sample lost.
55
-------
Table 22. Summary of Data and Analysis of Variance for Lead In
Vegetation (unwashed)
Test Farm
Control Farm
No. of** Mean No. of**
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 326.00 9
9 979.44 9
9 823.00 9
8+ 118.15 9
Mean
(ug/gm)
25.74
41.13
37.64
15.44
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 141.262 726.288
3 23.928 41.009
2 0.645 1.657
3 4.336 7.431
2 0.235 0.604
6 0.697 0.597
6 0.454 0.389
47 9.141
P
.0001
.0001
.2000
.0006
.5558
.7330
.8826
**
For calculation of means and analysis of variance, minimum detectable
limit values (5.00 ug/gm for washed vegetation; 1.00 ug/gm for washings)
were used for sample measurement below these limits.
One sample lost.
56
-------
Table 23. Summary of Data and Analysis of Variance for Zinc in
Vegetation (unwashed)
Test Farm
Control Farm
No. of Mean No. of
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 60.20 9
9 82.18 9
9 102.88 9
**
8 36.11 9
Mean
(ug/gm)
157.62
78.40
32.39
31.16
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 1.107 5.416
3 7.362 12.007
2 2.442 5.975
3 6.272 10.230
2 0.593 1.451
6 0.831 0.678
6 1.134 0.924
47 9.605
P
.0229
.0001
.0051
.0001
.2435
.6702
.5127
**
One sample lost.
57
-------
Table 24. Summary of Data and Analysis of Variance for Cadmium In
Washed Vegetation
Test Farm
Control Farm
No. of ** Mean No. of **
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 2.53 8
9 6.98 2
9 7.29 0
7 1.11 1
Mean
(ug/gm)
.83
.73
.70
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 53.420 479.563
3 10.450 31.271
2 0.075 0.336
3 13.122 39.266
2 0.220 0.987
6 0.476 0.712
6 0.682 1.020
47 5.236
P
.0001
.0001
.7209
.0001
.6179
.6438
.4248
**
Samples below lower detectable limit (0.50 ug/gm) excluded; analysis of
variance based on maximum values (0.50 ug/gm) for sample tests that
were below lower detectable limit.
One value missing.
58
-------
Table 25. Summary of Data and Analysis of Variance for Copper in
Mashed Vegetation
Test Farm
Control Farm
No. of Mean No. of
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 11.13 9
9 14.63 9
9 16.11 9
8** 5.34 9
Mean
(ug/gm)
8.72
6.24
6.06
4.64
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Si te
Season*Site
Farm*Season*Site
Residual (errotf)
Sum of
d.f. Squares F
1 5.377 119.268
3 5.478 40.504
2 0.192 2.131
3 2.463 18.208
2 0.112 1.243
6 0.076 0.282
6 0.256 0.948
47 2.119
P
.0001
.0001
.1282
.0001
.2976
.9421
.5286
**0ne value missing.
59
-------
Table 26. Summary of Data and Analysis of Variance for Lead in
Mashed Vegetation
Test Farm
Control Farm
No. of Mean No. of **
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 267.56 9
9 771.67 9
9 711.67 9
8+ 87.54 5
Mean
(ug/gm)
13.19
19.36
24.50
5.80
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 187.765 985.125
3 33.455 58.509
2 0.378 0.991
3 2.749 4.808
2 0.004 0.011
6 0.626 0.547
6 0.499 0.436
47 8.958
P
.0001
.0001
.6194
.0056
.9902
.7712
.8516
**
Samples below lower detectable limit (5.0 ug/gm) excluded; analysis of
variance based on maximum values (5.0 ug/gm) for sample tests that
were below lower detectable limit.
One value missing.
60
-------
Table 27. Summary of Data and Analysis of Variance for Zinc in
Washed Vegetation
Test Farm
Control Farm
No. of Mean No. of
Season Samples (ug/gm) Samples
Fall
Winter
Spring
Summer
9 55.11 9
9 61.70 9
9 85.67 9
8** 29.36 9
Mean
(ug/gm)
141.33
48.10
26.56
26.51
Analysis of Variance
Source
Farm
Season
Site
Farm*Season
Farm*Site
Season*Site
Farm*Season*Site
Residual (error)
Sum of
d.f. Squares F
1 1.156 5.358
3 7.264 11.218
2 ' 1.247 2.889
3 6.012 9.285
2 1.270 2.943
6 1.545 1.193
6 1.611 1.244
47 10.144
P
.0236
.0001
.0640
.0002
.0609
.3260
.3010
**
m
One value missing.
61
-------
Table 28.
Summary of Data and Analysis of Variance for Cadmium
in Hair
Test Farm
Control Farm
Season
Fall
Winter
Spring
Summer
No. of
Samples
8
8
8
8
Mean
(ug/gm)
1.29
1.74
2.80
0.67
No. of
Samoles
8
8
8
**
Mean
(ug/gm)
.06
.13
.05
.04
Analysis of Variance
Source
Farm
Season
Cow within farm
Farm*Season '
Season*Cow within farm
Duplicate analysis error
d.f .
1
3
6
3
18
32
Sum of
Squares
163.190
11.334
1.578
3.211
6.934
3.003
F P
423.630 0.0000
9.807 0.0005
0.683 0.6658
2.779 0.0710
**0ne sample below lower detectable limit excluded; analysis of
variance based on maximum value (i.e. 0.01 uq/qm) for the
sample test that was below lower detectable limit.
62
-------
Table 29.
Summary of Data and Analysis of Variance for Copper
in Hair
Test Farm
Control Farm
No. of
Season Samoles
Fall 8
Winter 8
Spring 8
Summer 8
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow within farm
Mean
(ug/gm)
8.26
7.76
6.94
7.99
Analysis of
d.f.
1
3
6
3
18
Duplicate analysis error 32
No. of
Samples
8
8
8
8
Variance
Sum of
Squares F
0.047 2.226
0.179 2.802
0.536 4.196
0.041 0.642
0.383
0.356
Mean
(ug/gm)
7.25
7.84
6.81
7.41
0.
0.
0.
0.
p
1530
0694
0082
5979
63
-------
Table 30. Summary of Data and Analysis of Variance for Lead
in Hair
Test Farm
Control Farm
No. Of
Season Samples
Fall 8
Winter 8
Spring 8
Summer 8
Ana
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow within farm
Duplicate analysis error
Mean
(ug/gm)
94.13
87.50
96.50
66.00
lysis of
d.f.
1
3
6
3
18
32
NO. Of
Samples
8
8
8
8
Variance
Sum of
Squares
233.536
7.414
4.317
2.790
5.374
6.272
Mean
(ug/gm)
2.19
3.92
2.13
0.88
F
782.272 0.
8.278 0.
2.410 0.
3.115 0.
p
0000
0011
0691
0521
64
-------
Table 31,
Summary of Data and Analysis of Variance for Zinc
in Hair
Test Farm
Control Farm
No. of
Season Samples
Fall 8
Winter 8
Spring 8
Summer 8
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow within farm
Mean
(ug/gm)
104.50
134.88
130.50
93.30
Analysis of
d.f.
1
3
6
3
18
Duplicate analysis error 32
No. of
Samples
8
8
8
8
Variance
Sum of
Squares
0.096 3
1.694 20
0.641 3
0.021 0
0.493
2.019
Mean
(ug/gm)
93.75
115.88
101.88
82.59
F
.514 0.
.619 0.
.901 0.
.252 0.
p
0772
0000
0114
8588
65
-------
Table 32.
Summary of Data and Analysis of Variance for Cadmium
in Blood
Test Farm
Control Farm
No. of
Season Samples
Fall 8
Winter 6
Spring 6
Summer 7
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow within farm
,+ Mean
(ug/100
1.74
0.38
0.60
0.76
Analysis of
d.f.
1
3
6
3
18
Duplicate analysis error 32
No. of **
ml) Samples
8
4
6
8
Variance
Sum of
Squares F
0.249 0.437
29.366 17.195
2.537 0.743
0.678 0.397
10.247
6.270
Mean
(ug/100 ml)
2.16
0.38
0.80
0.36
P
0.5167
0.0000
0.6226
0.7568
**
i
Samples below lower detectable limit excluded; analysis of
variance based on maximum values (i.e. 0.02 ug/100 ml) for
sample tests that were below detectable limits.
66
-------
Table 33.
Summary of Data and Analysis of Variance for Copper
in Blood
Test Farm
Control Farm
Season
Fall
Winter
Spring
Summer
Source
Farm
Season
Cow within
Farm*Season
Season*Cow
No. of Mean
Samples (ug/100 ml
8 85.88
8 97.13
8 63.48
8 76.13
Analysis of
d.f.
1
3
farm 6
3
within farm 18
Duplicate analysis error 32
No. of
) Samples
8
8
8
8
Variance
Sum of
Squares
1.117 42
0.448 5
0.306 1
0.455 5
0.468
0.241
Mean
(ug/100 ml)
97.25
111.00
109.75
98.13
F P
.966 0.0000
.748 0.0061
.960 0.1254
.839 0.0057
67
-------
Table 34. Summary of Data and Analysis of Variance for Lead
in Blood
Test Farm
Control Farm
No. of Mean No. of Mean
Season Samples (ug/100 ml) Samples (ug/100 ml)
Fall
Winter
Spring
Summer
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow withi
Duplicate analys
8 34.00
8 46.50
8 58.75
8 28.13
Analysis of
d.f.
1
3
6
3
n farm 18
is error 32
8
8
8
8
Variance
Sum of
Squares F
30.168 233.265
4.071 10.497
0.655 0.845
3.438 8.864
2.327
1.399
18.
8.
10.
6.
0.
0.
0.
0.
88
75
38
63
P
0000
0003
5523
0008
68
-------
Table 35.
Summary of Data and Analysis of Variance for Zinc
in Blood
Test Farm
Control Farm
No. of Mean No. of Mean
Season Samples (ug/100 ml) Samnles (ug/ 100 ml)
Fall
Winter
Spring
Summer
Source
Farm
Season
Cow within farm
'Farm*Season
Season*Cow withi
Duplicate Analys
8 389.75 8 495.25
8 391.50 8 376.88
8 425.25 8 379.13
8 402.50 8 372.50
i
Analysis of Variance
Sum of
d.f. Squares F p
1 0.000 0.024 0.8776
3 0.178 3.367 0.4116
6 0.565 5.339 0.0025
3 0.297 5.615 0.0068
n farm 18 0.318
is error 32 0.588
69
-------
Table 36. Summary of Data and Analysis of Variance for Cadmium
in Milk
Test Farm
Control Farm
No. of ^ Mean No. of Mean
Season Samples (ug/100 ml) Samples** (ug/100 ml)
Fall 3 .30 4
Winter 6 .42 4
Spring 2 .30 1
Summer 1 .20 5
.43
.40
.30
.34
Analysis of Variance
Sum of
Source d.f. Squares F
Farm 1 0.036 0.180
Season 3 0.973 1.607
Cow within farm 6 1.068 0.882
Farm*Season 3 0.602 0.994
Season*Cow within farm 18 3.632
Duplicate analysis error 32 2.093
P
0.6764
0.2228
0.5278
0.4181
*x
**
Samples below lower detectable limit excluded; analysis of
variance based on maximum values (i.e. 0.2 ug/100 ml) for
sample tests that were below lower detectable limits.
70
-------
Table 37.
Summary of Data and Analysis of Variance for Copper
in Milk
Test Farm
Control Farm
Season
Fall
Winter
Spring
Summer
No. of ^
Samples
4
3
8
1
Mean
(ug/100 ml)
13.50
6.43
8.48
9.00
No. of ;
Samples
5
6
8
4
Mean
(ug/100 ml)
8.66
10.07
10.28
11.50
Analysis of Variance
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow within farm
Duplicate analysis error
d.f.
1
3
6
3
18
32
Sum of
Squares
0.
0.
1.
0.
1.
1.
196
204
588
578
539
177
2
0
3
2
F
.296
.795
.096
.253
0.
0.
0.
0.
P
1470
5127
0291
1171
**
Samples below lower detectable limit excluded; analysis of
variance based on maximum values (i.e. 7.0 ug/100 ml) for
sample tests that were below lower detectable limits.
71
-------
Table 38.
Summary of Data and Analysis of Variance for Lead
in Milk
Test Farm
Control Farm
Season
Fall
Winter
Spring
Summer
No. of +J
Samples
4
8
8
7
t Mean
(ug/100 ml)
3.50
20.25
25.00
5.71
No. of **
Samples
8
8
7
0
Mean
(ug/100 ml)
13.00
8.00
6.86
Analysis of Variance
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow within farm
Duplicate analysis error
d.f.
1
3
6
3
18
32
Sum of
Squares
2.662
22.266
1.492
22.630
4.829
5.028
F
9.924
27.666
0.927
28.118
P
0.0055
0.0000
0.4992
0.0000
**
Samples below lower detectable limit excluded; analysis of
variance based on maximum values (i.e. 2.0ug/100 ml) for
sample tests that were below lower detectable limit.
72
-------
Table 39.
Summary of Data and Analysis of Variance for Zinc
in Milk
Test Farm
Control Farm
Season
Fall
Winter
Spring
Summer
Source
Farm
Season
Cow within farm
Farm*Season
Season*Cow with
Duplicate analy
No. of Mean No. of
Samples (ug/100 ml) Samples
8 193
8 339
8 275
8 313
Analysis
d.f.
1
3
6
3
in farm 18
sis error 32
.38 8
.25 8
.75 8
.75 8
of Variance
Sum of
Squares
0.843 2
2.577 2
3.150 1
0.753 0
5.354
0.391
Mean
(ug/100 ml)
280.00
345.88
375.88
343.75
F p
.835 0.1095
.889 0.0641
.765 0.1633
.844 0.4877
73
-------
100
o
00
8
v
.0
O.
=*» 40
20
D
D
D
D Fall
Winter
O Spring
Summer
20 40
60 80 100
jjg Pb/g Hair
120 140 160
Figure 2. Relationship Between Lead Concentrations
in Blood and Hair of Cows on Test Farm
74
-------
100
TJ
o
o
CD
80
E
O 60
O
40
20-
D
D
T
T 1
D Fall
Winter
O Spring
Summer
10 20 30
jjg Pb/IOOml Milk
40
Figure 3. Relationship Between Lead Concentrations
in Blood and Milk of Cows on Test Farm
75
-------
H. Cattle Tissues
Lead was found in higher concentrations in the liver,
kidney cortex, muscle and bone of the project owned test
cow than in corresponding tissues of the project owned
control cow (Table 40). Cadmium was also higher in liver
and especially the kidney cortex of the test cow than the
control cow. Zinc was higher in liver and bone of the control
cow than in the liver and bone of the test cow, and copper
was higher in all tissues tested from the control cow. There
were no large differences between levels of each of the 4
metals in the muscle samples from the test and control cows.
The highest concentration of Cd was in the kidney cortex;
copper was highest in liver; and Pb and Zn were highest in
blood. The test cow had approximately 17 times higher level
of Pb in her liver than the control cow and almost 16 times
more Pb in her kidney cortex than the control cow.
I. Human Consumption of Meat and Milk from Cows Exposed to
Production Sources of Heavy Metals
None of the cows, on either the test or control farms
became ill, so they represent heavy metal exposed cattle
that would pass routine inspection and enter meat and milk
supplies. Schroeder and Tipton estimated that the lead
intake averages 100-500 ug/day, assuming a person consumes
about 2,000 gm of food and drink per day. Questions that
might be asked are: Would substitution of meat and milk from
high metal exposed cows for "normal" meat and milk be harmful
76
-------
Table 40. Results of Cd, Cu, Pb and Zn Analyses of Tissues
Collected at End of Study Period from Genetically
Related Cows on Test and Control Farms
*
Mean value (ug/gtn)
Element and tissue
Cadmium
Liver
Kidney cortex
**
Muscle
Bone
Copper
Liver
Kidney cortex
**
Muscle
Bone
Lead
Liver
Kidney cortex
**
Muscle
Bone
Zinc
Liver
Kidney cortex
**
Muscle
Bone
Test Cow
0.90
3.70
0.10*
<0.05
7.25
2.75
1.30
0.58
2.35
3.75
0.19
9.00
33.35
17.55
43.50
70.05
Control Cow
0.24
1.40
0.10*
<0.05
60.00
3.90
1.50
0.74
0.14
0.24
0.06
7.1
51.6
19.6
41.9
88.5
Mean value of 2 duplicate samples
**
Diaphragm
*0ne sample below lower detectable limit (0.10 ug/gra)
77
-------
to some persons? If it is harmful, under what circumstances
will harm result? Assuming that a growing boy, 8-10 years of
age, eats 6 oz of meat and drinks 1 qt of milk per day, the
consumption of meat and milk from the test cow rather than
the control cow would result in an added 123 ug lead per day.
Before this excess dietary lead could result in toxicity, it
would be necessary for a person to have considerable exposure
to other sources and a resultant high body burden. Other
human health effects of lead such as neurological changes,
howevdr, may result from chronic exposure to subtoxic doses.
A comparison of the meat and milk Pb values with those
for garden crops provides some perspective for evaluation of
the dietary implications. Kehoe et_ al_. found lead in practi-
cally all food items tested including samples from a primitive
region far from industrial and mining activities. Leaf and
root vegetables are usually higher than kernel and other
vegetables. Because of the variety of food items that make
up the diet, at the present time food items such as vegetables
probably contribute more lead than the meat and milk components.
It is, however, disturbing that currently the lead content of
some food is considerably higher than in the past.
Even though meat and milk from exposed cattle may not
presently constitute a general risk for the consumer, reasonable
tolerances would help to both protect the consumer against
extreme situations and provide an incentive for the affected
businesses to end the mounting lead contamination of the
environment. For example, the lead concentration in soil at
78
-------
the 60 ft site increased 219%, 140 ft site increased 257%
and 220 ft site increased 284% during a 9 month period on
the test farm. The soil there already is approximately 10
times higher in lead than control farm soil. Natural lead
removal processes are grossly inadequate to balance the
amount of lead being deposited on the soil. The build up
of lead has been fairly rapid because the smelter at Glover
first started production in 1968. Extensive trucking of ore
from the mines in Clark National Forest started at that
same time.
The only restrictions on lead in foods in the United
States are Food and Drug Administration tolerances for fruit,
contained in regulations which were enacted to protect against
1 o
the effects of improper use of lead arsenate orchard sprays.
These tolerances range from 1 ppm for citrus to 7 ppm for
apples, apricots and tomatoes. Great Britain has adopted lead
I rt _ O I
tolerances in foods and Canada has proposed similar standards.
Their tolerance for lead in liver is 2 ppm and fish and edible
bone meal is 10 ppm. The British standard permits up to 0.2
ppm in milk. Under the British and Canadian standards, both
the slaughtered test cow's liver and kidneys Pb concentrations
would have exceeded the tolerance limit. One test cow's milk
In an earlier progress report, dated September 19, 1972, it was
stated that all specimens were under British regulations for beef
products. Since that time it has been determined that the Lead
in Food Regulations of 1961 established the limit of 2.0 ppm in
liver. The 5.0 ppm limit in the Regulation apparently applies
to canned meat products and meat extracts.
79
-------
sample collected In January and all 4 test cows' milk
samples collected in April exceeded the British milk standard
of 0.2 ppm. All of the other samples from the test farm cows,
the control cows and a cow located on a farm 7.6 miles west
from Glover on State Highway 72/21 (thus primarily exposed
to ore spillage instead of smelter sources of heavy metal
contamination) were below the British milk standards.
J. Garden Crops
A few samples of garden crops raised in the vicinity of
the test and control farms were also collected (Table 41).
The test area samples were collected from a farm approximately
2 miles north of the test farm. The available gardens did not
have lettuce or root vegetables so the samples tested were
green beans, bell peppers and tomatoes. The levels of Cd,
Cu, Pb and Zn were generally low and there were no differences
between the test and control farms. Other garden samples
collected in the Glover area have contained higher than normal
levels of lead.22
K. Lead Translocation
The concentrations of lead at each level of the food chain
were compared to derive some estimates that might be used in
evaluating the consequences of increased environmental contami-
nation on the lead levels in meat and milk produced in an area.
A translocation model was developed for the components of the
ecosystem under study, and corresponding lead concentrations
were abstracted from the data for the test farm (Figure 4) and
80
-------
Table 41. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and
Zinc (Zn) Analyses of Garden Crop Samples Collected
in the Vicinity of the Test and Control Farms, July 28,
1972
Location & Item
Element (ug/gm)
Cd
Cu
Pb
Zn
Test Area
Green Beans <.5
Bell Pepper <.5
Tomato .75
Control Area
Green Beans <.5
Bell Pepper <.5
Tomato <.5
10.4
10.3
9.2
9.4
11.5
5.8
5.3
<5.0
5.0
<5.0
<5.0
<5.0
33.5
30.0
28.2
40.5
28.2
17.0
81
-------
the control farm (Figure 5). The entire study period (i.e.
4 samplings) was used for determining the lead levels in air,
soil, vegetation, and water that would have contributed to the
cows' body burden and the levels measured in hair, blood,
milk, liver, kidney cortex, muscle and bone of the cows slaugh-
tered at the end of the study period. The 220 ft samples were
used in these calculations because they represented, better
than the 60 ft and 140 ft samples, the overall levels that
would contribute to the cow's body burden. Additional samples
of soil and vegetation were collected on both the test and
control farms in October 1971 and July 1972 at 440 ft from
the highway. These samples, from near the centers of the fields,
were very close to the 220 ft values thus indicating that the
220 ft site was far enough from the highway to represent the
general level in the pasture.
From the data presented in Figures 4 and 5, it can be
seen that a difference between dustfall Pb on test and control
farms of approximately 10 fold, corresponded approximately to
3.2 times higher muscle Pb concentration and a 5 times higher
milk Pb concentration for the slaughtered test cow than for
the slaughtered control cow. A similar relationship was found
when suspended lead values from the air filter data were used.
o
The mean of the suspended lead values (2.1671 ug/m ) on the
test farm for the sampling periods was approximately 15 times
higher than the mean of the sampling periods on the control
farm (0.1431 ug/m3).
Soil samples would be more easily obtained than dustfall
82
-------
AIR
DUSTFALL
87,70 MG/M2/MO
SUSPENDED LEAD
2,1671/uG/M3
SOIL
75,57 /XG/GM
VEGETATION
ROOTS
197,37/iG/GM
TOPS
509,43 |iG/GM
WATER
0,012 MG/L
BLOOD MILK HAIR
30,5 10,0 63,50
/AG/100ML /XG/100ML /IG/GM
COW
LIVER
2,4
/ifi/GM
KIDNEY MUSCLE
3,7 0,19
fxG/GM ftG/GM
BONE
9,0
Figure 4. Test Farm Lead Translocation Model
83
-------
AIR
DUSTFALL
8,95 MG/M2/MO
SUSPENDED LEAD
SOIL
14,94/AG/GM
VEGETATION
ROOTS
TOPS
10,85jtG/GM
WATER
0,006 MG/L
BLOOD MILK HAIR
8,0 2,0 0,55
JAG/100ML ^U3/100ML JiG/GM
COW
LIVER
0,11
jiG/GM
KIDNEY MUSCLE BONE
0,21 0,06 3,6
/AG/GM /AG/GM ftG/GM
Figure 5. Control Farm Lead Translocation Model
84
-------
or air filter samples for predicting the muscle and milk lead
levels of cattle grazing on the soil. The 5 times higher mean
soil Pb concentration for all samplings on the test farm than
on the control farm corresponded to the previously described
3.2 times higher muscle Pb and 5 times higher milk Pb on the
test farm than on the control farm. On an equivalent basis,
the test cow's blood Pb concentration was 1/246 the test farm
soil concentration and the control cow's blood Pb concentration
was 1/187 the control farm soil concentration. This relation-
ship should not, however, be expected to be the same in other
situations involving markedly different Pb contamination
sources. For example, in the models developed for the test
and control farm, water appeared to have very little contribu-
tion to the cattle's intake of lead. The pH of the soil, type
of vegetation, use of fertilizers and lime, rainfall and other
meteorological conditions would also affect the relationships
between air and soil lead levels and the levels found in animal
food products for human consumption produced in a given area.
On the control farm, there was a general dilution in the
lead concentrations at each step in transport between soil and
biological tissues (Figure 4). The roots had a lower concen-
tration than soil, unwashed vegetation tops lower than roots,
and all body tissues were lower than the tops. The bone
concentration of lead was higher than other body tissues sampled
and milk was less than 1/4 the blood lead level.
On the test farm, a different pattern was observed. The
85
-------
concentration of lead in roots was 2.6 times higher than
soil, unwashed vegetation tops were 2.6 times higher than
roots, and finally all body tissues were less than the
tops. Milk had between 1/3 and 1/4 the concentration of
lead found in the blood.
The high lead levels for unwashed vegetation on the
test farm obviously reflected the airborne contamination
because the washed vegetation tops were only 84.5% the
level for unwashed vegetation tops (i.e. the washings con-
tained 79 ug Pb/gm or accounted for 15.5% of the unwashed
tops value). The consistent findings in all seasons of
higher lead concentrations in roots than in soil on the test
farm, but not on the control farm, indicates that under these
conditions of relatively high levels of contamination, there
was bio-magnification of lead in the roots. These observations
also lend support to the view that much of the lead in vege-
tation, foliage and roots, enters the plant by foliar
absorption.
It is commonly thought that in an area of lead contamination,
that horses are more likely to develop lead poisoning than cattle
25-27
grazing on the same pasture. In fact, that relationship
has been observed in the Glover area as documented horse deaths
due to lead poisoning occurred, but no cattle deaths have been
diagnosed as lead poisoning. It has been suggested that the
grazing habits of the horse may be a reason for the greater
86
-------
apparent susceptibility of the horse, versus the cow, to lead
28
poisoning. Horses occasionally pull forage out by the roots
and eat the roots and attendant soil along with the forage.
The data reported here show that the soil and root lead con-
centrations are much less than unwashed vegetation tops so
a horse would have less intake if the roots substituted for
some of the tops in its diet. Therefore, it seems that the
basis for observations of horses being afflicted more than
cattle by lead poisoning in an area of contamination is for
other reasons than their grazing habits, probably a lower
biological tolerance on the part of the horse.
L. Intake and Assimilation of Lead by Cattle
Of the total lead intake, only a portion is assimilated
by the body. Assimilation occurs in two ways: absorption
from the alimentary tract and absorption from the respiratory
tract. Lead transported via these 2 pathways contribute to
the body burden, and each pathway will be considered separately
to facilitate the determination of the total amount of lead
assimi la ted.
1. Lead intake from the diet
An estimate of the daily ration of a cow can be arrived
at by knowing its nutritional needs and the nutritional
value of the food available to the cow for consumption. The
basis used for determining the daily nutritional require-
ment was megacalories of digestible energy, which in turn
is dependent on body weight, milk production, butterfat
87
-------
content of the milk and period of gestation. From the
foodstuffs available and their dates of feeding, a ration
was calculated that was adequate in fulfilling the cow's
daily requirement for energy.
At the test farm, the ration consisted of ground corn
and hay or pasture forage depending on the season of the
year, i.e. hay in the winter and pasture forage the rest
of the year. At the control farm, the ration was essen-
tially the same except that corn silage was offered along
with hay in the winter.
During each sampling period, grain and vegetation
samples were collected. Hay and silage samples were obtained
during the winter and spring sampling. Laboratory results
were reported as ug/gm; therefore, by knowing the amounts
of grain, hay, silage, or pasture forage the cow consumes,
it was possible to calculate the total amount of lead
ingested. The daily intakes of the project owned cows on
the test farm and on the control farm were calculated from
\ pg
the ration and the nutritive requirements of each cow.
It was estimated that, depending on the season, the test
cow consumed 18-21 kg feed per day and the control cow
consumes 26-32 kg feed per day. Assuming a cow drinks 29
gallons of water per day, the intake of lead from water on
the test farm (0.012 mg/1) and control farm (<0.006 mg/1)
was negligible. Based upon feed intake, the test cow was
consuming 8.65 mg Pb per kg of body weight, or 4762.92 mg Pb
-------
per day, and the control cow was consuming 0.78 mg Pb
per kg of body weight, or 430.54 mg Pb per day, over the
entire year. The specific values for the 4 seasons are
shown in Table 42. Based upon radioisotope studies, one
percent of this dietary intake was assumed to be absorbed
by the body.30
2. Lead intake from respiration
An estimate of the amount of lead inhaled per day by
a cow can be computed if the average concentration of
airborne suspended lead is known. Determination of sus-
pended lead was accomplished by continuous air sampling
during 4 to 6 weeks of the 13 weeks in a sampling period.
Suspended lead in air on the test farm remained relatively
constant during the fall, spring and summer months (Table
43). The winter period, however, had a level 2 times
greater than the mean value for all seasons on the test
farm. At the control farm, the level of suspended lead
declined steadily throughout the year with the last period
being less than 50% of the first period. Overall, the
test farm had higher suspended lead levels than the control
farm with the test/control ratio for lead being 16.5. On
the control farm, lead concentration in air was assumed to
be stable at the location of air sampling approximately 400
meters from the highway and the levels found in the first
4 weeks of each sampling period.
Multiplying the lead concentrations in ambient air by
89
-------
Table 42. Dally Dietary Intake and Respiratory Intake of Lead
by Project Owned Test Cow and Control Cow by Season
Test Cow
Control Cow
Season
i
Dietary intake
All seasons
Fall
Winter
Spring
Summer
mg Pb/kg
body wt/day
k
8.65
7.65
10.05
14.13
2.77
mg Pb/day
4762.92
4205.40
5529.28
7772.73
1524.04
mg Pb/kg
body wt/day
0.78
0.88
0.71
0.95
0.59
mg Pb/day
430.54
486.44
388.59
520.11
327.02
Respiratory intake
All seasons
Fall
Winter
Spring
Summer
0.00057
0.00045
0.00110
0.00036
0.00037
0.3126
0.2464
0.6050
0.1978
0.2011
0.00004
0.00006
0.00004
0.00003
0.00002
0.0207
0.0320
0.0201
0.0179
0.0127
Assumption: 550 kg body weight
Assumption: 156.9942 m /day inhaled air
90
-------
Table 43. Comparison of Suspended Cd, Cu, Pb and Zn on Test and
Control Farms
**
Test Farm (ug/m )
Control Farm (ug/m )
Season
Cd
All seasons .0259
Fall
Winter
Spring
Summer
.03
16
.0420
.01
.01
37
30
Cu
.0282
.0278
.0404
.0274
.0147
2
1
3
1
1
Pb
.1474
.5692
.8536
.5507
.3001
Zn'
.5141
.7261
.7601
.1725
.3446
Cd
.0023
.005
.001
.001
.001
1
4
3
5
Cu
.0068
.0057
.0130
.0041
.0028
Pb
.1304
.2037
.1282
.1068
.0804
Zn
.4111
.5754
.8384
.0141
.1127
**
Gelman Glass Fiber filters
Approximately 4 week sampling period for each season; the season total
is a weighted average of the season-specific values.
Values corrected by subtracting blank value from the sample
measurement.
91
-------
the cows' total respiratory volume in a day (156.9942 m ;
from Brody ) would result in the amount of lead inhaled
by cows each day. For the purposes of estimation, it was
assumed that the cow was similar to man with 30% pulmonary
retention of inhaled lead. The absolute amount of lead
via the respiratory tract was only 0.19% as great as the
amount of dietary assimilation on the test farm and 0.13%
as great as the amount of dietary assimilation on the
control farm.
Total lead assimilation
By combining the amount of lead absorption from food
and water and the amount retained from inhaled air, it was
determined that the test cow was assimilating during the
season of highest exposure (spring), approximately 0.14
mg/kg body weight and the control cow was receiving
approximately 0.01 mg/kg body weight during the same season.
25
Hammond and Aronson have estimated that the minimum
cumulative lethal dose for a cow is 6-7 mg/kg body weight,
32
and Allcroft succeeded in producing a chronic syndrome
and death after 33 months of continuous feeding of 5-6 mg
Pb/kg/day to a steer. The mean seasonal daily intake
calculated in the present study for the test cow (Table 42)
was above these dosages in all of the seasons except summer,
but the cow was never observed to be ill or exhibit signs
of lead toxicity. This is not necessarily in conflict with
the earlier observations as this cow was 10 years old.
92
-------
The minimum cumulative lethal dose would be expected to
be higher for older cows, as younger animals are usually
more sensitive to lead.
4. Relationship between total lead assimilation and blood lead
Based upon data collected by Kehoe, the relationship
between total lead assimilated from both the gastrointestinal
tract and lungs of man were compared with the subjects
blood levels.33 Allcroft32 and Allcroft and Blaxter34 have
published results of cattle experiments in which the blood
lead concentrations were determined for various amounts
of lead fed in the ration. It was assumed in these studies
that the contribution of lead in inhaled air was negligible.
The present study provided an opportunity to examine under
natural conditions the relationship between total lead
absorption in the cow, from both ingested and inhaled lead,
and the blood lead levels.
As shown in Figure 6, there is a peak in assimilated
lead during the spring period on both farms with the test
cow being approximately 15 times higher than the control
cow. The blood lead levels also peaked at this time with
the level of the cow on the test farm being almost 5 times
greater than the level of the cow on the control farm.
The milk lead level of the test cow also reflected this
increase of lead intake by increasing and peaking during
this period, although the lead level in the control cow's
milk did not peak and continued to decline. Overall, the
93
-------
mean blood lead value of the cow on the test farm was 3.8
times greater than the mean blood lead value of the cow on
the control farm, and the mean milk lead value of the cow
on the test farm was 1.6 times greater than the mean milk
lead value of the cow on the control farm.
M. Meteorological Effects and Sources of Contamination on the
Test Farm
Mind data were collected at the test farm for a total of
331 days over a 366 day period. Mechanical break-down of
recorder and occasionaly lack of strip-chart paper accounted
for 35 days for which no data was collected. The main 3 wind
directions and their corresponding mean velocities were South
(26.59%) at 4.4 mph, Southwest (24.17%) at 2.2 mph and North
(23.87%) at 5.6 mph.
Tables 44 and 45 contain seasonal data for suspended Cd
and Pb levels in air, vehicular traffic (for the previous year)
wind direction and wind velocity at the test farm. It is
north of the smelter and north of State Highway 72/21 so wind
direction and velocity would affect in a similar manner the
recognized sources of heavy metal contamination, namely vehicu-
lar emissions, smelter stack emissions (the stack is 610 ft
tall), ore truck spillage, and dust from stockpiled ore on the
smelter premises. Assuming that the seasonal pattern of ve-
hicular traffic by the farm during the study period was similar
to the preceding year, there was a negative relationship with
the levels of Cd and Pb in the air. In the winter and spring
94
-------
when the suspended Cd and Pb levels were highest in the air,
the traffic was lowest. Therefore, it appears that the
contribution by vehicular emissions has a minor role in deter-
mining the airborne Cd and Pb levels. It is not known if the
ore truck traffic corresponds to the total vehicular traffic
pattern. The trucking of ore to the smelter operated inde-
pendently of the smelter operating schedule because the ore
was stockpiled to ensure a constant supply when the smelter
sinter and blast furnaces were operating. Due to the hilly
terrain and adverse driving conditions in the winter, it is
thought that the amount of trucking was less in the winter than
in other seasons. A more important factor is wetting the lead
ore loaded onto the trucks to avoid dust and covering of the
two ore hoppers on each truck to avoid spillage. It is not
known if these two procedures were performed more diligently
in some seasons than others; however, the project investigators
have personally seen uncovered ore trucks on State Highway
72/21 during all 4 seasons.
The smelter is an obvious major source of airborne lead
in the area. During 1971, the smelter production was erratic
because of a labor strike. The strike was ended in Feb., 1971
and the numbers of days that the sinter and blast furnace were
operated during each of the previously described sampling
periods in this study were consistent.
The wind, as determined by the weather station maintained
on the test farm, was from a quadrant (SE,S,SW) that would blow
95
-------
the smelter plume and any dust from the property towards the
test farm more of the time during the winter and summer periods
than other periods. Conversely, the wind was observed to
blow towards the smelter, away from the farm, much of the time
during the fall and spring study periods. Therefore, it
appeared that the southerly wind had a major effect, increasing
the levels of suspended Pb and Cd on the test farm. The wind
velocity had variable effect on the levels of suspended Pb and
Cd. The hypothesis that the main source of the contamination
on the test farm is the smelter stack emissions, is supported
by the 10 fold higher dustfall Pb at the 220 ft site and 13
fold higher airborne suspended Pb on the test farm as compared
with corresponding measurements on the control farm. It is
unlikely that the main highway sources (engine emissions and ore
spillage) would contribute much to the 220 ft measurements.
Furthermore, the gradient had leveled off at the 220 ft site to
values that were similar to the general levels found near the
center of the field at the 440 ft collection location. The
distance between the test farm and the smelter property,
approximately 800 meters or 0.5 mile, would greatly diminish
the amount of surface wind distribution of stockpiled ore to
the test farm during times when the wind was blowing from a
southern quadrant.
It was difficult to fully evaluate the contribution of
spillage from ore trucks to the levels of lead in the cattle
on the test farm, so another cow from a farm on the north side
96
-------
of State Highway 72/21 approximately 7.6 miles west of
Glover was sampled in the fall, spring and summer (Table 46).
The mean concentrations of lead in both blood and milk of the
cow exposed to ore spillage (plus background due primarily to
vehicular emissions but not smelter emissions) were inter-
mediate between that of the cows exposed to multiple sources
on the test farm and cows exposed to only background on the
control farm. The milk lead mean concentration of the ore
spillage exposed cow (11.8 ug/100 ml) was almost as large
as the milk concentrations of the cows on the test farm.
97
-------
Table 44. Settleable and Suspended Cadmium (Cd) by Season, Vehicular
Traffic, and Wind Direction and Velocity.
Samples
Measurement per season
Dustfall Cd1
(mg/mz/mo.)
60' 3
140' 3
220' 3
2
Total Suspended Cd
(ug/m3) 3
Vehicular Traffic3
Season
Fall
0.8716*
0.8680
0.5466
0.0316
76077
Winter
1.8316
1.6824
1.4711
0.0420
58706
Spring
0.5954X
0.5589*
0.4825
0.0106
85107
Summer
1.6082
1.3249
1.2407
0.0209
96196
Percent
Mind Direction
Toward Farm (SE,S,SU)
Not Toward Farm
A
Wind Velocity*
0-5 mph
5-10 mph
10-15 mph
100.00
39.58
60.42
100.00
59.30
40.70
100.00
49.45
50.55
100.00
60.44
39.56
Percent
100.00
66.67
29.88
3.45
100.00
51.52
39.39
9.09
100.00
66.67
30.95
2.38
100.00
72.53
26.38
1.09
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
+0ne sample lost during lab preparation; therefore, the value presented
is based on two samples.
1Fall=Oct.2,1971-Jan.6,1972; Winter=Jan.6,1972-Apr.1,1972; Spring=Apr.1,1972-
Jul.1,1972; Summer=Jul.1,1972-Oct.1,1972.
2
Weighted average based on percent of total collection period that each
filter was used. Fall=0ct.3,1971-0ct.30,1971; Winter=Jan.6,1972-Feb.6,1972;
Spring=Apr.l,1972-Apr.28,1972 and May 5,1972-May 19,1972; Summer=Jul.1,1972-
Jul.28,1972 and Aug.4,1972-Aug.20,1972.
3
Factored average traffic volume for 1970-1971 time periods equivalent to
footnote 1; from Missouri State Highway Commission data.
4
Average velocity of daily-prevailing-winds.
98
-------
Table 45. Settleable and Suspended Lead (Pb) by Season, Vehicular
Traffic, and Wind Direction and Velocity.
Measurement
Samples
per season
Season
Fall
Winter
Spring
Summer
Dustfall Pb1
2
(mg/m /mo.)
60'
140'
220'
/
Total Suspended Pb'
3 85.9698 170.3140
3 130.4618 130.9470
3 76.4983 122.9700
100.5931 121.9600
87.0318 89.0289
72.7931 78.4986
(ug/m°)
Vehicular Traffic
Mind Direction
Toward Farm (SE,S,SW)
Not Toward Farm
Wind Velocity4
0-5 mph
5-10 mph
10-15 mph
3 1.5692
76077
100.00
39.58
60.42
100.00
66.67
29.88
3.45
3.8536 1.2599
58706 85107
Percent
100.00 100.00
59.30 49.45
40.70 50.55
Percent
100.00 100.00
51.52 66.67
39.39 30.95
9.09 2.38
1.2810
96196
100.00
60.44
39.56
100.00
72.53
26.38
1.09
Vall-Oct. 2, 1971-Jan. 6, 1972; Winter=Jan. 6, 1972-Apr. 1, 1972; Spring=
Apr. 1, 1972-July 1, 1972; Summer=July 1, 1972-Oct. 1, 1972.
2
Weighted average based on percent of total collection period that each
filter was used. Fall=0ct. 3, 1971-Oct. 30, 1971; Winter=Jan. 6, 1972-
Feb. 6, 1972; Spring=Apr. 1, 1972-Apr. 28, 1972; and May 5, 1972-
May 19, 1972; Summer=Ju1y 1, 1972-July 28, 1972 and Aug. 4, 1972-
Aug. 20, 1972.
3
Factored average traffic volume for 1970-1971 time periods equivalent to
footnote 1; from Missouri State Highway Commission data.
4
Average velocity of daily-prevailing-winds.
99
-------
Table 46. Comparison of Mean Bovine Blood and Milk Lead Values by
Season and Location of Farm
Test Farm
Farm 7.6 Miles
West of Glover
Control Farm
Specimen
and Season
Blood
All seasons
Fall
Winter
Spring
Summer
Milk
All seasons
Fall
Winter
Spring
Summer
No. of
Samples
32
8
8
8
8
32
8
8
8
8
uq/100 ml
41.8
34.0
46.5
58.8
28.1
13.0
1.8
20.3
25.0
5.0
No. of
samples
4
2
-
1
1
4
2
-
1
1
uq/100 ml
17.5
22.0
-
8.0
18.0
11.8
16.5
-
14.0
<2.0
No. of
Samples
32
8
8
8
8
32
8
8
8
8
uq/100 ml
11.2
18.9
8.8
10.4
6.6
6.8
13.0
8.0
6.0
<2.0
100
-------
TEST FARM
o
o
o
o
m
O_
D>
E
.16
.14
.12-
.10
.08-
,06
100 _
E
O
80 2
60
40
20
CQ
Oct
Jan
Apr
Jul
Assimilated Pb
a a Blood Pb
A- - -A Milk Pb
CONTROL FARM
O»
jf.
,010-
.008-
.006-
.004-
,002-
0
25 g
o
o
20
-15
-10
- 5
o
o
£
CD
Oct
Jan
Apr
Jul
Figure 6. Total Assimilated Lead, Blood Lead, and
Milk Lead for Project Owned Test Cow and
Control Cow
-------
VI.
REFERENCES
-------
VI. REFERENCES
1. Committee on Biological Effects of Atmospheric Pollutants:
Airborne Lead in Perspective. National Academy of Sciences,
Wash. D.C., 1972.
2. Kobayashi, J.: Relation between the "Itai-Itai" disease and
the pollution of river water by cadmium from a mine. Proc.
5th International Water Pollution Research Conference, San
Francisco, July-August, 1970.
3. Underwood, E.J.: Trace elements in human and animal nutrition.
Academic Press, New York, 1956.
4. Chow, T.J. and Patterson, C.C.: The occurrence and signifi-
cance of lead isotopes in pelagic sediments. Geochim. Cosmo-
chim. Acta 26:263-308, 1962.
5. Missouri Geological Survey and Water Resources: The World's
No. 1 Lead Producer. Missouri Mineral News, Rolla, Mo.
Vol. 11 , No. 3, 1971.
6. Gibson, F.W.: New Buick lead smelter incorporates forty years
of technical advances. Engineering and Mining Journal, 1968.
7. Wixson, B.G., and Bolter, E.: Evaluations of stream pollution
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5th Annual Conf. on Trace Substances in Environmental Health,
University of Missouri, Columbia, 1972.
8. Connor, J.J., Erdman, J.A., Sim, J.D., and Ebens, R.J.: Roadside
effects on trace element content of some rocks, soils and plants
of Missouri. jhi_ Hemphil 1 , D.D. (ed.) Proc. 4th Annual Conf.
Trace Subst. in Environ. Health. Univ. of Missouri, Columbia, Mo.
1970.
103
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9. Pierce, J.O. and Cholak, J.: Lead, chromium and molybdenum by
atomic absorption. Arch. Environ. Health 13:208-212, 1966.
10. Analytical Methods for Atomic Absorption Spectrophotometry.
Perkin-Elmer Corp., Norwalk, Conn., 1968.
11. Pickett, E.E.: Current capabilities in analysis of trace
substances: flame photometry and atomic absorption. Proc. 1st
Annual Conf. Trace Substances in Environmental Health. Univ.
of Missouri, Columbia, 1967.
12. Kirtyohann, S.R. and Pickett, E.E.: Spectral interferences in
atomic absorption Spectrophotometry. Anal. Chem. 38:585-587,
1966.
13. Mitchell, R.L. and Reith, J.W.S.: The lead content of pasture
herbage. J. Sci. Food Agric. 17:437-440, 1966.
14. Everett, J.C., Day, C.L. and Reynolds, D.: Comparative survey
of lead at selected sites in the British Isles in relation to
air pollution. Food Cosmet. Toxicol. 5:29-35, 1967.
15. Nishujama, K. and Nordberg, G.F.: Adsorption and elution of
cadmium on hair. Arch. Environ. Health 25:92-96, 1972.
16. Shroeder, H.A. and Tipton, I.H.: The human body burden of lead.
Arch. Environ. Health 17:965-978, 1968.
17. Kehoe, R.A., Thamann, F. and Cholak, J.: On the normal absorp-
tion and excretion of lead. I. Lead absorption and excretion
in primitive life. J. Ind. Hyg. 15:257-272, 1933.
18. Food and Drug Administration: Title 21 Food and Drugs, Section
120.194. Code of Federal Regulations, U.S. Govern. Printing
Office.
104
-------
19. Ministry of Agriculture, Fisheries and Food and Ministry of
Health: The Lead in Food Regulation, 1961. Food and Drugs
Composition, England and Wales, No. 1931. Her Majesty's
Stationery Office, 1961.
20. Peden, J.D.: A survey of the arsenic, copper and lead
contents of pigs and other animal livers. J. Assoc. Public
Analysts 8:14-19, 1970.
21. Anonymous: Lead. Food Chemical News 12:12, Oct. 5, 1970.
22. Hemphill, D.: Personal communication, Nov., 1972.
23. Chamberlain, A.C.: Interception and retention of radioactive
aerosols by vegetation. Atmos. Environ. 4:57-78, 1970.
24. Mueller, P.K. and Stanley, R.L.: Origin of lead in surface
vegetation. AIHL Report No. 87. State of Calif Dept. of
Public Health, Berkeley, Calif.
25. Hammond, P.B. and Aronson, A.L.: Lead poisoning in cattle
and horses in the vicinity of a smelter. Annals N.Y. Acad.
Sci. Vol. Ill, Art. 2, pp. 595-611, 1964.
26. Schmitt, N., Larsen, A.A., McCausland, E.D. and Seville, J.M.:
Lead poisoning in horses; an environmental health hazard.
Arch. Environ. Health 23:185-195, 1971.
27. California Air Resources Board: A Joint Study of Lead
Contamination Relative to Horse Deaths in Southern Solano
County. December, 1972.
28. Aronson, A.L.: Lead poisoning in cattle and horses following
long-term exposure to lead. Amer. J. Vet. Res. 33:627-629, 1972.
29. National Academy of Science: Nutrient Requirements of Dairy
Cattle. National Research Council Publication No. 1349, Third
Revised Edition, 1966.
105
-------
30. Stanley, R.E., Mullen, A.A., and Bretthauer, E.W.: Transfer
to milk of ingested radiolead. Health Physics 21:211-215, 1971
31. Brody, W.: Bioenergetics and Growth. Missouri Agriculture
Experiment Station Publication, 1944.
32. Allcroft, R.: Lead as a nutritional hazard to farm livestock.
IV. Distribution of lead in the tissues of bovines after
ingestion of various lead compounds. J. Comp. Path. 60:190-
208, 1950.
33. Kehoe, R.A.: The metabolism of lead in man in health and
disease. The Harben Lectures, 1960. J. Roy. Inst. Public
Health Hyg. 24:1-81, 101-120, 129-143, 177-203, 1961.
34. Allcroft R. and Blaxter, K.L.: Lead as a nutritional hazard to
farm livestock. V. The toxicity of lead to cattle and sheep
and an evaluation of the lead hazard under farm conditions.
J. Comp. Path. 60:209-218, 1950.
106
-------
VII.
ACKNOWLEDGMENTS
-------
VII. ACKNOWLEDGMENTS
The project investigators wish to thank Dr. Arthur A.
Case, School of Veterinary Medicine and Dr. Delbert D.
Hemphill, Program Director of the Environmental Trace
Substances Center, University of Missouri, Columbia, for
many helpful suggestions in conducting this research, and
Dr. David Hutcheson, Sinclair Comparative Medicine Research
Farm for performing nutritive analyses of the cattle
rations. The assistance and cooperation of the staffs of
the Missouri Air Conservation Commission, the Missouri
Division of Health, the lead industries, and the University
of Missouri Cooperative Extension Service are gratefully
acknowledged. Appreciation is also extended to those
persons who allowed the use of their land and livestock for
sample collection.
-------
VIII.
APPENDIX TABLES
-------
Table 1. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Test Farm near Glover, Missouri
During October 2, 1971 - January 6, 1972.
Type of Animal
Sample ID No.
2
Blood 1
Blood 2
Blood 3
Blood 4
Milk2 1
Milk 2
Milk 3
Milk 4
Hair3 1
Hair 2
Hair 3
Hair 4
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.3
Roots 140 ft.
Roots 220 ft.
3
Vegetation, unwashed
60 ft.
140 ft.
220 ft.
3
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60 ft.4 '
Dustfall 140 ft.
Dustfall 220 ft.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Mean Value
Cd
1.60
1.50
2.00
1.85
.30*
**
.40*
.20*
1.20
.90
.95
2.10
.58
.53
.56
1.66
1.06
1.90
4.
4.18*
4.40*
2.96
2.93
2.37
2.30
.8716+
.8680
.5466
Cu
74.50
94.00
89.00
86.00
12.00
**
15.00
**
9.10
8.45
8.60
6.90
10.13
9.63
9.80
23.00
23.00
19.67
14.01
11.50
11.98
12.13
10.23
11.03
1.8703
2.8291
1.9466
Pb
35.50
33.50
27.50
39.50
2.50
**
4.50
**
160.00
83.00
83.00
50.50
71.67
43.00
41.33
211.33
115.00
298.33
396.00
296.00
286.00
304.00
251.33
247.33
86.0115
130.4618
76.5575
Zn
408.50
435.00
389.00
326.50
290.50
67.00
324.00
92.00
118.50
126.50
86.00
87.00
26.67
22.00
23.67
105.33
60.67
73.67
66.13
59.40
55.07
58.33
55.00
52.00
1.3546
1.1621
1.8268
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
Mean value of blood and milk samples as ug/100 ml; Oct. 2, 1971.
Mean value of hair, soil, root and vegetation samples as ug/g; Oct. 2«-9, 1971.
4 2
Mean value as mg/m /mo; Oct. 2, 1971 - Jan. 6, 1972.
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**All sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
Two sample values were below lower detectable limit; therefore, the value
presented is based on one sample.
no
-------
Table 2. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Control Farm near Ellington,
Missouri, During October 2, 1971 - January 4, 1972.
Type of Animal
Sample ID No.
Blood2 1
Blood 2
Blood 3
Blood 4
2
Milk 1
Milk 2
Milk 3
Milk 4
3
Hair 1
Hair 2
Hair 3
Hair 4
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.
Roots 140 ft.
Roots 220 ft.
3
Vegetation, unwashed
60 ft.
140 ft.
220 ft.
3
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60 ft.4
Dustfall 140 ft.
Dustfall 220 ft.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Mean value
Cd
.95
4.40
1.15
2.15
**
.30*
.60
.20*
.06
.05
.06
.07
.41
.42
.38
1.22+
.79
.86
**
**
1.07+
.76
.93
.69
.0356*
.3052
.2492
Cu
89.50
94.50
107.00
98.00
9.00
10.00*
7.65
**
7.45
6.50
7.65
7.40
5.43
6.77
4.80
10.63
11.67
11.67
8.95
13.37
10.06
7.97
10.47
7.73
.2373
1.3090
.7342
Pb
17.50
14.00
22.50
21.50
12.50
16.00
9.50
14.00
2.85
1.55
2.40
1.95
13.67
13.00
12.33
15.33
8.20
14.67
21.47
24.97
15.10
17.57
11.70
10.30
1.6204
46.3752
29.7586
Zn
520.00
456.00
481.50
523.50
451.00
205.50
281.50
182.00
90.50
94.00
98.00
92.50
49.67
25.00
17.00
259.33
36.33
78.00
337.37
70.23
65.27
309.33
62.33
52.33
1.5871
2.7328
1.1310
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
2
Mean value of all blood and milk samples in ug/100 ml; Oct. 2, 1971.
Mean value of hair, soil, root and vegetation samples as ug/g; Oct. 2-3, 1971.
4 2
Mean value as mg/m /mo; Oct. 2, 1971 - Jan. 4, 1972.
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
Two sample values were below lower detectable limit; therefore, the value
presented is based on one sample.
Ill
-------
Table 3. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Test Farm near Glover, Missouri,
During January 6 - March 31, 1972.
Type of Animal
Sample ID No.
Blood2
Blood
Blood
Blood
Milk2
Milk
Milk
Milk
Hair
Hair
Hair
Hair
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.
Roots 140 ft
Roots 220 ft
Vegetation,
60 ft.
140 ft.
220 ft.
1
2
3
4
1
2
3
4
1
2
3
4
3
unwashed
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
Mean Value
Cd
1
1
2
1
1
3
2
2
9
8
6
.40*
.40*
.35
.40
.30
.50
.50*
.40*
.55
.10
.35
.95
.06
.79
.88
.90
.67
.83
+
72I
4>
.41
.72
Cu
92.
100.
112.
84.
**
**
**
8.
7.
7.
8.
7.
14.
10.
10.
32.
34.
34.
23.
19.
16.
00
00
50
00
90*
25
85
65
30
67
50
87
90
47
27
97
03
00
Pb
56.00
47.
38.
44.
20.
30.
16.
14.
87.
61.
98.
103.
122.
49.
61.
374.
196.
145.
1081.
1012.
845.
50
00
50
00
50
50
00
00
50
50
00
33
73
43
67
00
33
00
33
00
440
361
406
358
331
423
265
337
195
128
109
107
39
22
28
151
84
66
885
58
99
Zn
.50
.50
.00
.00
.50
.00
.00
.50
.00
.00
.50
.00
.20
.60
.93
.33
.67
.33
.33
.37
.63
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60
Dustfall 140
Dustfall 220
ft.4
ft.
ft.
3
3
3
3
3
3
7
7
5
1
1
1
.30
.97
.68
.8316
.6824
.4711
15.
15.
12.
3.
2.
2.
33
70
87
3897
5775
2957
756.
860.
698.
170.
130.
122.
67
00
33
3140
9470
9700
48
47
89
18
13
11
.97
.13
.00
.2331
.1568
.8101
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
Mean value of all blood and milk samples in ug/100 ml; Jan. 6, 1972
Mean value of hair, soil, root and vegetation samples as ug/g; Jan. 6, 1972.
4 2
Mean value as mg/m /mo; Jan. 6 - March 31, 1972.
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
112
-------
Table 4. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Control Farm near Ellington,
Missouri, During January 5 - April 2, 1972.
Type of Animal
Sample ID No.
Blood2 1
Blood 2
Blood 3
Blood 4
Milk2 1
Milk 2
Milk 3
Milk 4
Hair3 1
Hair 2
Hair 3
Hair 4
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.3
Roots 140 ft.
Roots 220 ft.
3
Vegetation, unwashed
60 ft.
140 ft.
220 ft.
3
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60 ft.4
Dustfall 140 ft.
Dustfall 220 ft.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Mean Value
Cd
.35
.30*
**
.50*
.55
**
**
.25
.18
.06
.08
.19
.66
.60
.55
.55
.70
.68
**
**
**
i
.90T
**
.55*
.0386*
**
**
Cu
109.00
102.00
121.00
112.00
11.90
7.70
10.60
**
9.70
6.70
7.55
7.40
6.83
8.87
7.03
18.13
20.97
22.97
9.20
10.03
9.03
6.07
7.07
5.60
.1682
.3111
.1156
Pb
13.50
6.00
8.00
7.50
8.50
15.00
5.00
3.50
3.95
1.02
2.70
8.00
15.47
15.23
14.70
9.50
6.80
9.27
**
132.00*
**
21.23
22.67
14.17
2.7708
1.6883
1.9713
Zn
346.50
430.50
325.50
405.00
484.00
178.50
357.00
364.00
115.50
111.00
117.00
120.00
23.47
23.43
19.57
41.53
46.93
48.20
108.07
73.73
53.40
56.33
49.13
38.83
1.6625
1.0660
1.1115
1 . . £ 1_1 J J -,, , V V
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
Mean value of all blood and milk samples in ug/100 ml; Jan. 5, 1972.
Mean value of hair, soil, root and vegetation samples as ug/g; Jan 5. 1972.
4 2
Mean value as mg/m /mo; Jan. 4 - April 2, 1972.
*One sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
Two sample values were below lower detectable limit; therefore, the value
presented is based on one sample.
113
-------
Table 5. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Test Farm near Glover, Missouri,
During April 1 - July 1, 1972.
Type of Animal
Sample ID No.
Blood2
Blood
Blood
Blood
Milk2
Milk
Milk
Milk
Hair
Hair
Hair
Hair
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.
Roots 140 ft
Roots 220 ft
Vegetation,
60 ft.
140 ft.
220 ft.
Vegetation,
60 ft.
140 ft.
220 ft.
Dustfall 60
Dustfall 140
Dustfall 220
1
2
3
4
1
2
3
4
1
2
3
4
3
.
3
unwashed
washed
ft.4
ft.
ft.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Mean Value
Cd
**
.
**
**
2.
2.
4.
2.
.
2.
3.
2.
**
8.
10.
7.
6.
7.
50
60
70
30*
30*
00
00
50
70
65
63
83
53
60
47
n
55+
33
57
97
5954
5589
4825
Cu
64
64
72
52
8
7
9
7
6
7
8
5
14
13
.25
.25
.50
.90
.90
.90
.40
.70
.20
.50
.45
.60
.57
.23
10.47
22
27
22
21
18
16
16
17
14
2
2
1
.67
.50
.33
+
.35
.37
.10
.50
.00
.83
.4622
.2803
.9644
1
Pb
46
87
43
59
20
20
24
35
84
93
143
66
99
84
82
343
293
290
851
807
810
696
718
720
100
84
72
.00
.00
.00
.00
.50
.50
.00
.00
.00
.00
.00
.00
.00
.67
.20
.33
.67
.00
.23
.07
.73
.67
.33
.00
.5931
.0318
.7931
428
525
394
353
323
341
134
304
145
133
126
117
41
Zn
.50
.00
.00
.50
.00
.50
.00
.50
.00
.50
.00
.50
.23
30.67
27
86
94
72
103
104
100
84
88
84
.57
.83
.17
.33
.23
.60
.80
.33
.00
.67
12.9044
14
10
.0149
.7524
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
Mean value of all blood and milk samples in ug/100 ml; Apr. 1, 1972.
Mean value of hair, soil, root and vegetation samples as ug/g; Apr. 1, 1972.
4 2
Mean value as mg/m /mo; April 1 - July 1, 1972.
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
114
-------
Table 6. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Control Farm near Ellington,
Missouri, During April 2 - June 30, 1972.
Type Animal
Sample ID No.
Blood2
Blood
Blood
Blood
Milk2
Milk
Milk
Milk
Hair3
Hair
Hair
Hair
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.
Roots 140 ft
Roots 220 ft
1
2
3
4
1
2
3
4
1
2
3
4
3
.
.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
Mean Value
Cd
.35
1.25
.80*
.80*
.30*
**
**
**
.04
.05
.07
.06
.57*
**
**
.71
.68
.70
Cu
96
103
128
111
10
5
16
8
7
5
6
7
7
8
7
16
15
15
Vegetation, unwashed
60 ft.
140 ft.
220 ft.
3
3
3
**
**
**
7
7
7
.25
.75
.00
.00
.65
.95
.35
.15
.55
.80
.50
.40
.33
.67
.47
.33
.00
.80
i
.06*
35I
.50*
Pb
9.
9.
10.
13.
7.
4.
7.
9.
2.
2.
00
00
oo'
50
00*
00
50
00
80
00
1.85
1.
19.
19.
18.
17.
28.
20.
59.
**
**
85
20
10
30
67
50
83
30*
Zn
328
431
313
444
470
245
374
414
115
96
100
95
21
22
27
41
34
39
.00
.50
.00
.00
.50
.00
.00
.00
.00
.50
.75
.25
.57
.43
.67
.00
.33
.17
36.77
30
30
.30
.10
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60
Dustfall 140
Dustfall 220
ft.4
ft.
ft.
3
3
3
3
3
3
**
**
**
.0594
.0483
.0507
5
6
6
.67
.33
.17
.3464
.3958
.2573
20.
27.
25.
4.
2.
2.
67
33
50
1959
1256
3355
30
24
24
2
2
1
.33
.50
.83
.1217
.0267
.3973
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
2
Mean value of all blood and milk samples in ug/100 ml; Apr. 2, 1972.
Mean value of hair, soil, root and vegetation samples as ug/g; Apr. 2, 1972.
4 2
Mean value as mg/m /mo; April 2 - June 30, 1972.
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
+One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
Two sample values were below lower detectable limit; therefore, the value
presented is based on one sample.
115
-------
Table 7. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Test Farm near Glover, Missouri,
July 1 - October 1, 1972
Type of Animal
Sample ID No.
Blood2 1
Blood 2
Blood 3
Blood 4
Milk2 1
Milk 2
Milk 3
Milk 4
Hair 1
Hair 2
Hair 3
Hair 4
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.
Roots 140 ft.
Roots 220 ft.
3
Vegetation, unwashed
60 ft.
140 ft.
220 ft.
3
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60 ft.4
Dustfall 140 ft.
Dustfall 220 ft.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Mean Value
Cd
1.85
.30*
.30
.35
**
**
**
.20*
.47
.84
.58
.79
.89
.73
.87
1.77
1.87
1.17
1.03
.65*
1.34
1.03
.65*
1.34
1.6082
1.3249
1.2407
Cu
73.00
86.00
67.50
78.00
9.00*
**
**
**
6.10
9.30
8.15
8.40
13.80
11.53
11.43
22.73
17.00
12.73
7.27
6.40
5.70
5.93
+
5.90
4.37
2.3932
1.8572
1.6542
Pb
33.50
30.50
30.50
18.00
3.50
3.00
20.00*
3.50
53.00
69.00
63.50
78.50
157.17
110.33
117.33
242.50
98.00
55.83
130.97
132.20
95.97
93.27
+
113.25
64.67
121.9600
89.0289
78.4986
Zn
425.00
455.00
420.00
310.00
390.00
335.00
230.00
300.00
102.75
93.35
84.10
93.00
42.17
27.13
30.43
105.00
35.17
33.50
47.73
32.60
26.83
37.70
29.50
20.93
19.9501
15.2785
13.5171
1 .
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
2
Mean value of all blood and milk samples in ug/100 ml; July 1, 1972.
Mean value of hair, soil, root and vegetation samples as ug/g; July 1, 1972.
4 2
Mean value as mg/m /mo; July 1 - Oct. 1, 1972.
*0ne sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
Two sample values were below lower detectable limit; therefore, the value
presented is based on one sample.
116
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Table 8. Results of Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn)
Analyses of Samples Collected on Control Farm near Ellington,
Missouri, July 1 - September 30, 1972.
Type of Animal
Sample ID No.
Blood2 1
Blood 2
Blood 3
Blood 4
2
Milk 1
Milk 2
Milk 3
Milk 4
Hair3 1
Hair 2
Hair 3
Hair 4
Soil 60 ft.3
Soil 140 ft.
Soil 220 ft.
Roots 60 ft.
Roots 140 ft.
Roots 220 ft.
3
Vegetation, unwashed
60 ft.
140 ft.
220 ft.
Vegetation, washed
60 ft.
140 ft.
220 ft.
Dustfall 60 ft.4
Dustfall 140 ft.
Dustfall 220 ft.
No. of
Samples
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
Mean Value
Cd
.30
.40*
.35
.40*
.20
**
.50
.30*
.06
.06
.02*
.02
**
.37*
**
.53+
.87
.69
**
.70*
**
**
.70*
**
.0322*
**
**
Cu
72.00
126.00
93.00
101.50
10.50
**
12.50
**
7.75
5.90
7.60
8.40
6.57
7.20
5.73
9.03
12.67
13.17
5.38
4.40
5.50
4.67
4.40
4.87
.2527
.3102
.1915
Pb
6.00
8.00
5.00
7.50
**
**
**
**
1.25
.55
.57
1.15
17.80
15.57
14.43
8.75*
10.73
11.50
-,.vw
5.40
6.60
i
5.00*
5.40
6.60
2.0869
1.3326
1.7423
Zn
380.00
355.00
350.00
405.00
450.00
230.00
335.00
360.00
83.70
78.25
85.70
82.70
17.87
16.57
12.63
84.57
38.00
41.25
37.80
25.73
29.93
31.67
23.67
21.87
1.9414
1.4283
1.2981
Calculated on a dry weight basis, except for blood and milk values which are
on a wet weight basis.
2
Mean value of all blood and milk samples in ug/100 ml; July 1, 1972.
Mean value of hair, soil, root and vegetation samples as ug/g; July 1, 1972.
4 2
Mean value as mg/m /mo; July 1 - sept. 30, 1972.
*One sample value was below lower detectable limit; therefore, the value
presented is based on one sample.
**A11 sample values were below lower detectable limits.
One sample value was below lower detectable limit; therefore, the value
presented is based on two samples.
Two sample values were below lower detectable limit; therefore, the value
presented is based on one sample.
117
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