United States
Environmental Protaction
Agency
Office of 'A/ale;
Regulations and Standards
Waahinaton. CC 20460
Water
, Juno, 1985
, a
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PREFACE
This document is one of a series of preliminary assessments dealing
with chemicals of potential concern in municipal sewage sludge. The
.purpose of these documents is to: (a) summarize the available data for
the constituents of potential concern, (b) identify the key environ-
mental pathways for each constituent related to a reuse and disposal
option (based on hazard indices), and (c) evaluate the conditions under
which such a pollutant may pose a hazard. Each document provides a sci-
entific basis for making an initial determination of whether a pollu-
tant, at levels currently observed in sludges, poses a likely hazard to
human health or the environment when sludge is disposed of by any of
several methods. These methods include landspreading on food chain or
nonfood chain crops, distribution and marketing programs, landfilling,
incineration and ocean disposal.
These documents are intended to serve as a rapid screening tool to
narrow an initial list of pollutants to those of concern. If a signifi-
cant hazard is indicated by this preliminary analysis, a more detailed
assessment will be undertaken to better quantify the risk from this
chemical and to derive criteria if warranted. If a hazard is shown to
be unlikely, no further assessment will be conducted at this time; how-
ever, a reassessment will be conducted after initial regulations are
finalized. In no case," however, will criteria be derived solely on the
basis of information presented in this document.
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TABLE OF CONTENTS
Page
PREFACE i
1. INTRODUCTION 1-1
2. PRELIMINARY CONCLUSIONS FOR IRON IN MUNICIPAL SEWAGE
SLUDGE 2-1
Landspreading and Distribution-and-Mark.eti.ng 2-1
Landfilling 2-2
Incineration 2-2
Ocean Disposal 2-2
3. PRELIMINARY HAZARD INDICES FOR IRON IN MUNICIPAL SEWAGE
SLUDGE 3-1
Landspreading and Distribution-and-Marketing 3-1
Effect on soil concentration of iron (Index 1) ,.. 3-1
Effect on soil biota and predators of soil biota
(Indices 2-3) 3-2
Effect on plants and plant tissue
concentration (Indices 4-6) 3-4
Effect on herbivorous animals (Indices 7-8) 3-10
Effect on humans (Indices 9-13) 3-14
Landf illing 3-22
Incineration 3-22
Ocean Disposal 3-22
4. PRELIMINARY DATA PROFILE FOR IRON IN MUNICIPAL SEWAGE
SLUDGE 4-1
Occurrence 4-1
Sludge 4-1
.Soil - Unpolluted 4-2.
Water - Unpolluted 4-2
Air 4-3
Food 4-3
11
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TABLE OP CONTENTS
(Continued)
Page
Human Effects 4-4
Ingestion 4-4
Inhalation 4-6
Plant Effects 4-6
Phytotoxicity 4-6
Uptake 4-7
Domestic Animal and Wildlife Effects 4-8
Toxicity 4-8
Uptake 4-8
Aquatic Life Effects 4-8
Toxicity 4-8
Uptake 4-9
Soil Biota Effects 4-9
Toxicity 4-9
Uptake 4-9
Physicochemical Data for Estimating Fate and Transport 4-9
5. REFERENCES 5-1
APPENDIX. PRELIMINARY HAZARD"INDEX CALCULATIONS FOR
IRON IN MUNICIPAL SEWAGE SLUDGE A-l
111
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SECTION 1
INTRODUCTION
This preliminary data profile is one of a series of profiles
dealing with chemical pollutants potentially of concern in municipal
sewage sludges. Iron (Fe) was initially identified as being of
potential concern when sludge is landspread (including distribution and
marketing).* This profile is a compilation of information that may be
useful in determining whether Fe poses an actual hazard to human health
or the environment when sludge is disposed of by this method.
The focus of this document is the calculation of "preliminary
hazard indices" for selected potential exposure pathways, as shown in
Section 3. Each index illustrates the hazard that could result from
movement of a pollutant by a given pathway to cause a given effect
(e.g., sludge -»• soil •* plant uptake •* animal uptake •*• human toxicity).
The values and assumptions employed in these calculations tend to
represent a reasonable "worst case"; analysis of error or uncertainty
has been conducted to a limited degree. The resulting value in most
cases is indexed to unity; i.e., values >1 may indicate a potential
hazard, depending upon the assumptions of the calculation.
The data used for index calculation have been selected or estimated
based on information presented in the "preliminary data profile",
Section 4. Information in the profile is based on a compilation of the
recent literature. An attempt has been made to fill out the profile
outline to the greatest extent possible. However, since this is a pre-
liminary analysis, the literature has not been exhaustively perused.
The "preliminary conclusions" drawn from each index in Section 3
are summarized in Section 2. The preliminary hazard indices will be
used as a screening tool to determine which pollutants and pathways may
pose a hazard. Where a potential hazard is indicated by interpretation
of these indices, further analysis will include a more detailed exami-
nation of potential risks as well as an examination of site-specific
factors. These more rigorous evaluations may change the preliminary
conclusions presented in Section 2, which are based on a reasonable
"worst case" analysis.
The preliminary hazard indices for selected exposure routes
pertinent to landspreading and distribution and marketing are included
in this profile. The calculation formulae for these indices are shown
Jin the Appendix. The indices are rounded to two significant figures.
* Listings were determined by a series of expert workshops convened
during March-May, 1984 by the Office of Water . Regulations and
Standards (OWRS) to discuss landspreading, landfilling, incineration,
and ocean disposal, respectively, of municipal sewage sludge.
1-1
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SECTION 2
PRELIMINARY CONCLUSIONS FOR IRON IN MUNICIPAL SEWAGE SLUDGE
The following preliminary conclusions have been derived from the
calculation of "preliminary hazard indices", which represent conserva-
tive or "worst case" analyses of hazard. The indices and their basis
and interpretation are explained in Section 3. Their calculation
formulae are shown in the Appendix.
I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING
A. Effect on Soil Concentration of Iron
Landspreading of municipal sewage sludge at low application
rates (5 mt/ha) is not expected to increase soil concentra-
tions of Fe above background levels. At higher application
rates (50 mt/ha and 500 mt/ha), a slight increase in Fe soil
concentrations may occur (see Index 1).
B. Effect on Soil Biota and Predators of Soil Biota
Conclusions were not drawn because index values could not be
calculated due to lack of data (see Indices 2 and 3).
C. Effect on Plants and Plant Tissue Concentration
Phytotoxic effects due to soil concentrations of Fe resulting
from landspreading of sludge could not be determined due to
lack of data (see Index 4). When municipal sewage sludge is
applied to soil at a low rate, no increase in levels of plant
tissue concentration of Fe is anticipated. If sludge is
applied at 50 mt/ha to 500 mt/ha, the Fe concentration in
plants grown in the amended soil may increase moderately (see
Index 5). These elevated plant tissue concentrations of Fe
are not expected to be precluded by phytotoxicity (see
Index 6).
D. Effect on Herbivorous Animals
The consumption of plants grown in sludge-amended soils by
herbivorous animals is not expected to pose a toxic hazard due
to Fe (see Index 7). The incidental ingestion of sludge-
amended soil, however, may pose a toxic hazard to grazing ani-
mals when sludge containing a high concentration of Fe is
applied (see Index 8).
E. Effect on Humans
Landspreading of sludge is not expected to pose a health haz-
ard due to Fe for humans who consume plants grown in sludge-
amended soil, except possibly for adults when sludge contain-
ing a high concentration of Fe is applied at a high rate (see
2-1
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Index 9). The consumption of animal products derived from
animals that have either grazed plants grown in sludge-amended
soil or have ingested sludge-amended soil is not expected to.
pose a health threat due to Fe for humans (see Indices 10 and
11). Ingestion of sludge-amended soil or pure sludge by todd-
lers may increase the health hazard due to Fe above the hazard
posed by ingestion of unamended soil. This increase may be
substantial when sludge containing a high concentration of Fe
is applied at a high rate. For adults, ingestion of sludge-
amended soil or sludge is not expected to pose a health hazard
due to Fe (see Index 12). The aggregate amount of Fe in the
toddler diet resulting from landspireading of sludge may
slightly increase the health hazard due to Fe, above the risk
posed by the acceptable daily intake of Fe. For adults, a
health hazard due to the aggregate amount of Fe in the diet is
only expected when sludge containing a high concentration of
Fe is landspread at a high rate (see Index 13).
II. LANDFILLING
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
III. INCINERATION
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
IV. OCEAN DISPOSAL
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
2-2
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SECTION 3
PRELIMINARY HAZARD INDICES FOR IRON
IN MUNICIPAL SEWAGE SLUDGE
I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING
A. Effect on Soil Concentration of Iron
1. Index of Soil Concentration Increment (Index 1)
a. Explanation - Shows degree of elevation of pollutant
concentration in soil to which sludge is applied.
Calculated for sludges with typical (median if
available) and worst (95th percentile if available)
pollutant concentrations, respectively, for each of
four sludge loadings. Applications (as dry matter)
are chosen and explained as follows:
0 mt/ha No sludge applied. Shown for all indices
for purposes of comparison, to distin-
guish hazard posed by sludge from pre-
existing hazard posed by background
levels or other sources of the pollutant.
5 mt/ha Sustainable yearly agronomic application;
i.e., loading typical of agricultural
practice, supplying s$Q kg available
nitrogen per hectare.
50 mt/ha Higher application as may be used on
public lands, reclaimed areas or home
gardens.
500 mt/ha Cumulative loading after years of
application.
b. As sumptions/Limitations - Assumes pollutant is dis-
tributed and retained within the upper 15 cm of soil
(i.e., the plow layer), which has an approximate
mass (dry matter) of 2 x 10-* mt/ha.
c. Data Used and Rationale
i. Sludge concentration of pollutant (SC)
Typical 28,000 yg/g DW
Worst 78,700 ug/g DW
The typical and worst sludge concentrations are
the median and maximum values of sludge
3-1
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concentration data from 14 cities (Cunningham
et al., 1975; Dowdy and Larson, 1975; Furr et
al., 1976; and Sommers et al., 1976). (See
Section 4, p. 4-1.)
ii. Background concentration of pollutant in soil
(BS) = 20,000 ug/g DW
Shacklette et al. (1971 in TDI, 1981) reported
that the geometric mean of Fe concentration in
soils from western states was 20,000 ug/g,
while the geometric mean for eastern states was
15,000 Hg/g. Connor and Shacklette (1975 in
TDI, 1981) reported that the geometric means of
Fe concentration for different soil types range
from 4,700 to 43,000 Hg/g. Jackson (1964 in
TDI, 1981) reported that Fe concentrations for
most soils range from 7,000 to 42,000 Ug/g.
The value selected as the background concentra-
tion in soil was 20,000 Ug/g. This value was
selected because it falls near the center of
the ranges reported for different soil types.
(See Section 4, p. 4-2.)
Index 1 Values
Sludge Application Rate (mt/ha)
Sludge
Concentration 0 5 50 500
Typical
Worst
1
1
1.0
1.0
1.0
1.1
1.1
1.6
e. Value Interpretation - Value equals factor by which
expected soil concentration exceeds background when
sludge is applied. (A value of 2 indicates concen-
tration is doubled; a value of 0.5 indicates
reduction by one-half.)
f. Preliminary Conclusion - Landspreading of municipal
sewage sludge at low application rates (5 mt/ha) is
not expected to increase soil concentrations of Fe
above background levels. At higher application
rates (50 mt/ha and 500 mt/ha), a slight increase in
Fe soil concentrations•may occur.
Effect on Soil Biota and Predators of Soil Biota
1. Index of Soil Biota Toxicity (Index 2)
a. Explanation - Compares pollutant concentrations in
sludge-amended soil with soil concentration shown to
be toxic for some organism.
3-2
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b. Assumptions/Limitations - Assumes pollutant form in
sludge-amended soil is equally bioavailable and
toxic as form used in study where toxic effects were
demonstrated.
c. Data Used and Rationale
i. Index of soil concentration increment (Index 1)
See Section 3, p. 3-2.
ii. Background concentration of pollutant in soil
(BS) = 20,000 Ug/g DW
See Section 3, p. 3-2.
iii. Soil concentration toxic to soil biota (TB) -
Data not immediately available.
d. Index 2 Values - Values were not calculated due to
lack of data.
e. Value Interpretation - Value equals factor by which
expected soil concentration exceeds toxic concentra-
tion. Value >1 indicates a toxic hazard may exist
for soil biota.
f. Preliminary Conclusion - Conclusion was not drawn
because index values could not be calculated.
2. Index of Soil Biota Predator Toxicity (index 3)
a. Explanation - Compares pollutant concentrations
expected in tissues of organisms inhabiting sludge-
amended soil with food concentration shown to be
toxic to a predator on soil organisms.
b. Assumptions/Limitations - Assumes pollutant form
bioconcentrated by soil biota is equivalent in tox-
icity to form used to demonstrate toxic effects in
predator. Effect level in predator may be estimated
from that in a different species.
c. Data Used and Rationale
i. Index of soil concentration increment (Index 1)
See Section 3, p. 3-2. •
ii. Background concentration of pollutant in soil
(BS) = 20,000 ug/g DW
See Section 3, p. 3-2.
3-3
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iii. Uptake slope of pollutant in soil biota (UB) -
Data not immediately available.
In the only available study in which Fe content
in applied sludge and earthworms was measured
(Helmke et al., 1979), there was no clear
relationship between applied Fe and tissue Fe.
This may have been due in part to the low Fe
concentration in sludge of 11,600 Ug/g DW,
compared to 20,800 Ug/g DW in soil. (See
Section 4, p. 4-9.)
iv. Background concentration in soil biota (BB) =
730 ug/g DW
This background concentration in soil biota
represents the control value for earthworms
reported by Helmke et al. (1979). (See Section
4, p. 4-9.)
v. Feed concentration toxic to predator (TR) =
800 ug/g DW
Birds were selected as a model earthworm
predator. The only available information
indicating Fe concentrations toxic to birds was
for chickens. A diet containing 800 Ug/g in
the form of FeS04 • 7^0 was associated with
reduced growth in chicks (McGhee et al., 1965
in National Academy of Sciences (NAS), 1980).
This concentration is considered a conservative
choice, since the form of Fe fed to chicks is a
soluble form and, thus, may be absorbed more
readily then less soluble forms. (See Section
4, P; 4-12.)
d. Index 3 Values - Values were not calculated due to
lack of data.
e. Value Interpretation - Value equals factor by which
expected concentration in soil biota exceeds that
which is toxic to predator. Value > 1 indicates a
toxic hazard may exist for predators of soil biota.
f. Preliminary Conclusion - Conclusion was not drawn
because index values could not be calculated.
C. Effect on Plants and Plant Tissue Concentration
1. Index of Phytotoxicity (Index 4)
a. Explanation - Compares pollutant concentrations in
sludge-amended soil with the lowest soil
concentration shown to be toxic for some plant.
3-4
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b. Assumptions/Limitations - Assumes pollutant form in
sludge-amended soil is equally bioavailable and
toxic as form used in study where toxic effects were
demonstrated.
c. Data Used and Rationale
i. Index of soil concentration increment (Index 1)
See Section 3, p. 3-2.
ii. Background concentration of pollutant in soil
(BS) = 20,000 ug/g DW
See Section 3, p. 3-2.
iii. Soil concentration toxic to plants (TP) - Not
determined.
The forms of Fe that predominate in aerated
soils, i.e., the hydroxides and oxides of the
Fe III or ferric state, are practically insolu-
ble in water and are thus 'of limited availabil-
ity to plant roots. Under reducing conditions,
characterized by waterlogging and/or low pH,
the soluble Fe II or ferrous forms become more
prevalent (Fuller, 1977). Fe in sludge may be
present in the ferrous state, depending on the
oxygen status of the sludge. Under normal soil
conditions, soluble Fe added to soil is rapidly
precipitated as ferric hydroxide (FeO(OH]), and
then gradually converted to even less soluble
forms (Council for Agricultural Science and
Technology (CAST), 1976). However, at low- pH
(<5.-0) and especially in soils deficient in
manganese, Fe solubility is enhanced (CAST,
1976; Asghar and Kanehiro, 1981). Organic
matter can also have a reducing effect.in soil;
the additioH of sludge has been shown to cause
an increase in soluble soil Fe, even when the
sludge itself was low in soluble Fe (John and
Van Laerhoven, 1976).
Plants can tolerate high levels of soil Fe
under aerobic conditions, as evidenced by the
mean soil concentration of 20,000 Ug/g DW (see
Section 3, p. 3-2.), but soil solution
concentrations of soluble Fe as low as 100 mg/L
are associated with toxicity in rice (Tanaka et
al., 1966-in Foy et al., 1978) (See Section 4,
p. 4-10.) Thus, any hazard of Fe toxicity is
more a function of soil conditions than of Fe
concentration. While sludge addition can
promote reducing conditions in soil, this
3-5
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effect is independent of the sludge Fe
concentration. Liquid sludge is often phyto-
toxic when first applied, and this toxicity may
be due in part to reduced Fe, but this effect
is well known and ordinarily short-lived.
Therefore, a soil concentration of total Fe
resulting in phytotoxicity will not be stated,
and Index 4 will not be calculated. It should
be recognized, however, that addition of any
sludge that increases soil Fe (see Index 1) may
increase the hazard of phytotoxicity in soils
prone to such problems.
d. Index 4 Values - Values were not calculated due to
lack of data.
e. Value Interpretation - Value equals factor by which
soil concentration exceeds phytotoxic concentration.
Value > 1 indicates a phytotoxic hazard may exist.
f. Preliminary Conclusion - Index values were not cal-
culated because a soil concentration of total Fe
resulting in phytotoxicity could not be identified.
The hazard of Fe toxicity is more a function of soil
conditions than Fe concentration. However, it
should be recognized that any sludge addition that
increases soil Fe (see Index 1) may increase the
hazard of Fe phytotoxicity in soils prone to such
problems.
2. Index, of Plant Concentration Increment Caused by Uptake
(Index 5)
a. Explanation - Calculates expected tissue concentra-
tion increment in plants grown in sludge-amended
soil, using uptake data for the most responsive
plant species in the following categories: (1)
plants included in the U.S. human diet; and (2)
plants serving as animal feed. Plants used vary
according to availability of data.
b. Assumptions/Limitations - Assumes a linear uptake
slope. Neglects the effect of time; i.e., cumula-
tive loading over several years is treated equiva-
lently to single application of the same amount.
The uptake factor chosen for the animal diet is
assumed to be representative of all crops in the
animal diet. See also Index 6 for consideration of
phytotoxicity.
3-6
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c. Data Used and Rationale
i. Index of soil concentration increment (Index 1)
See Section 3, p. 3-2.
ii. Background concentration of pollutant in soil
(BS) = 20,000 Ug/g DW
See Section 3, p. 3-2.
iii. Conversion factor between soil concentration
and application rate (CO) = 2 kg/ha (ug/g)"1
Assumes pollutant is distributed and retained
within upper 15 cm of soil (i.e. plow layer)
which has an approximate mass (dry matter) of
2 x 103.
iv. Uptake slope of pollutant in plant tissue (UP)
Animal diet:
Wheat grain 0.0057 Ug/g tissue DW (kg/ha)"1
Human diet:
Lettuce leaf 0.0077 Ug/g tissue DW (kg/ha)"1
Wheat grain was selected to represent a grain
crop consumed by livestock. The uptake slope
was calculated from data presented by Sabey and
Hart (1975) in a field study investigating the
chemical composition of plants grown in sludge-
amended soil. Although higher uptake slopes
were available for sorghum grown in pots with
FeSO'4-amended soil (Fuller and Lanspa, 1975),
the data for wheat were considered more rele-
vant because the wheat was grown on sludge-
amended soil. Lettuce leaf was chosen to rep-
resent plants consumed by humans, based on a
field study by Dowdy and Larson (1975) in which
sludge was used. A higher slope for beet
tubers (John and Van Laerhoven, 1976) was not
used because total Fe was not reported and the
slope was based on soluble Fe. In addition, a
much higher slope for turnip greens (0.27 Ug/g
[kg/ha]~l) from a field study using sludge
(Miller and Boswell, 1979) was not selected
because it appeared to be anomalous when com-
pared with the other values available. (See
Section 4, p. 4-11.)
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v. Background concentration in plant tissue (BP)
Animal diet:
Wheat grain 36.3 Ug/g DW
Human diet:
Lettuce leaf 94 Ug/g DW
Background concentrations of Fe in wheat grain
and lettuce leaf were reported by Sabey and
Hart (1975) and Dowdy and Larson (1979),
respectively. Their studies provided data used
to calculate the uptake slopes. (See
Section 4, p. 4-11.)
d. Index S Values
Sludge Application
Rate (mt/ha)
Sludge
Diet Concentration 0 5 50 500
Animal
Typical
Worst
1.0
1.0
1.0
1.0
1.1
1.4
1.5
4.7
Human Typical 1.0 1.0 1.0 1.3
Worst 1.0 1.0 1.2 2.9
e. Value Interpretation - Value equals factor by which
plant tissue concentration is expected to increase
above background when grown in sludge-amended soil.
f. Preliminary Conclusion - When municipal sewage
sludge is applied to soil at a low rate, no increase
in levels of plant tissue concentration of Fe is
anticipated. If sludge is applied at 50 mt/ha to
500 mt/ha, the Fe concentrations in plants, grown in
the amended soil may increase moderately.
3. Index of Plant Concentration Increment Permitted by
Phytotoxicity (Index 6)
a. Explanation - Compares maximum plant tissue concen-
tration associated with phytotoxicity with back-
ground concentration in same plant tissue. The
purpose is to determine whether the plant concentra-
tion increments calculated in Index 5 for high
applications are truly realistic, or whether such
increases would be precluded by phytotoxicity.
b. Assumptions/Limitations - Assumes that tissue con-
centration will be a consistent indicator of
phytotoxicity.
3-8
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c. Data Used and Rationale
i. Maximum plant tissue concentration associated
with phytotoxicity (PP)
Animal diet:
Alfalfa (tops) 1206 Ug/g DW
Human diet:
Soybean (tops) 1320 Ug/g DW
No information was available on tissue con-
centration of Fe associated with phytotoxicity
for wheat or lettuce. Shetron (1979) reported
Fe concentrations as high as 1206 Ug/g in
alfalfa grown on Fe tailings. No effects were
observed on growth and development; however,
the study did not report data for yields.
Brown and Jones (1977 in Foy et al., 1978)
reported growth limitations in soybeans
containing tissue concentrations of 1320 Ug/g»
It is assumed that the tissue concentrations
associated with toxicity for alfalfa and
soybeans are representative of those for wheat
and lettuce. (See Section 4, p. 4-10.)
ii. Background concentration in plant tissue (BP)
Animal diet:
Alfalfa 200 Ug/g DW
Human diet:
Soybeans 200 Ug/g DW
The background concentration of Fe for alfalfa
is the concentration given for alfalfa meal in
TDI (1981). The concentration of Fe in the
upper leaves of soybean plants prior to pod set
was reported to be 100 to 200 Ug/g (TDI, 1981).
The higher concentration was selected to pro-
vide a conservative increment value. (See
Section 4, p. 4-7.) •
d. Index 6 Values
Plant Index Value
Alfalfa . 6.0
Soybeans 6.6
e. Value Interpretation - Value gives the maximum
factor of tissue concentration increment (above
background) which is permitted by phytotoxicity.
Value is compared with values for the same or
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similar plant tissues given by Index 5. The lowest
of the two indices indicates the maximal increase
which can occur at any given application rate.
£. Preliminary Conclusion - The index values for
alfalfa and soybeans are similar. Increases of Fe
concentrations in plant tissues above background
concentrations by a factor of 6 are expected to be
accompanied by phytotoxicity. Comparison to Index 5
indicates that the highest concentration factors
predicted for wheat or lettuce would not be expected
to be precluded by phytotoxicity.
Effect on Herbivorous Animals
1. Index of Animal Toxicity Resulting from Plant Consumption
(Index 7)
a. Explanation - Compares pollutant concentrations
expected in plant tissues grown in sludge-amended
soil with food concentration, shown to be toxic to
wild or domestic herbivorous animals. Does not con-
sider direct contamination of forage by adhering
sludge.
b. Assumptions/Limitations - Assumes pollutant form
taken up by plants is equivalent in toxicity to form
used to demonstrate toxic effects in animal. Uptake
or toxicity in specific plants or animals may be
estimated from other species.
c. Data Used and Rationale
i. Index of plant concentration increment caused
by uptake (Index 5)
Index 5 values used are those for an animal
diet (see Section 3, p. 3-8).
._i
ii. Background concentration in plant tissue (BP) =
36.3 yg/g DW
The background concentration value used is for
the plant chosen for the animal diet (see
Section 3, p. 3-8).
iii. Feed concentration toxic to herbivorous animal
(TA) = 477 Ug/g DW
Cattle fed diets containing iron citrate (a
highly available form) at 500 Ug/g or more (as
Fe) showed a trend toward poorer performance
(weight gain and feed consumption); however,
the effects were not statistically significant
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(Koong et al., 1970 in NAS, 1980). In the same
study, a level of 2500 Ug/g caused significant
reduction of feed intake and daily weight gain.
Standish et al. (1969 in NAS, 1980) reported
similar findings with slight reduction in
weight gain and feed conversion at dietary
FeS(>4 levels of 477 Ug/g (as Fe) and
significant reduction in growth and feed intake
at 1677 Ug/g. Although no significant effects
were observed at this dietary level, 477 Ug/g
was selected to conservatively estimate the
feed concentration toxic to herbivorous
animals.
Less available forms are tolerated at higher
levels. For example, when FeO(OH) was admini-
stered in amounts corresponding to a dietary
concentration of 1400 Ug/g DW (for a total con-
centration, including food sources of Fe, of
1980 Ug/g DW), cattle performance • was
unaffected, although biochemical indices showed
a marked Cu deficiency had developed (Campbell
et al., 1974). However, since the availability
of Fe forms in common animal feeds is not known
(NRC, 1979), toxicity values for the more
available forms are used as a conservative
approach. (See Section 4, p. 4-12.)
d. Index 7 Values
Sludge Application Rate (mt/ha)
Sludge
Concentration 0 5 50 500
Typical
Worst
0.076
0.076
0.077
0.080
0.081
0.11
0.11
0.36
e. Value Interpretation - Value equals factor by which
expected plant tissue concentration exceeds that
which is toxic to animals. Value > 1 indicates a
toxic hazard may exist for herbivorous animals.
f. Preliminary Conclusion - The consumption of plants
grown in sludge-amended soils by herbivorous animals
is not expected to pose a toxic hazard due to Fe.
2. Index of Animal Toxicity Resulting from Sludge Ingestion
.(Index 8)
a. Explanation - Calculates the amount of pollutant in
a grazing animal's diet resulting from sludge adhe-
sion to forage or from incidental ingestion of
sludge-amended soil and compares this with the
dietary toxic threshold concentration for a grazing
animal.
3-11
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Assumptions/Limitations - Assumes that sludge is
applied over and adheres to growing forage, or that
sludge constitutes 5 percent of dry matter in the
grazing animal's diet, and that pollutant form in
sludge is equally bioavailable and toxic as form
.used to demonstrate toxic effects. Where no sludge
is applied (i.e., 0 mt/ha), assumes diet is 5 per-
cent soil as a basis for comparison.
Data Used and Rationale
i. Sludge concentration of pollutant (SC)
Typical 28,000 pg/g DW
Worst 78,700 yg/g DW
See Section 3, p. 3-1.
ii. Background concentration of pollutant in soil
(BS) = 20,000 yg/g DW
See Section 3, p. 3-2.
iii. Fraction of animal diet assumed to be soil (GS)
= 5%
Studies of sludge adhesion to growing forage
following applications of liquid or filter-cake
sludge show that when 3 to 6 mt/ha of sludge
solids is applied, clipped forage initially
consists of up to 30 percent sludge on a dry-
weight basis (Chaney and Lloyd, 1979; Boswell,
1975). However, this contamination diminishes
gradually with time and growth, and generally
is not detected in the following year's growth.
For example, where pastures amended at 16 and
32 mt/ha were grazed throughout a growing sea-
son (168 days), average sludge content of for-
age was only 2.14 and 4.75 percent,
respectively (Bertrand et al., 1981).., It seems
reasonable to assume that animals may receive
long-term dietary exposure to 5 percent sludge
if maintained on a forage to which sludge is
regularly applied. This estimate of 5 percent
sludge is used regardless of application rate,
since the above studies did not show a clear
relationship between application rate and ini-
tial contamination, and since adhesion is not
cumulative yearly because of die-back.
Studies of grazing animals indicate that soil
ingestion, ordinarily <10 percent of dry weight
of diet, may reach as high as 20 percent for
cattle and 30 percent for sheep during winter
3-12
-------
months when forage is reduced (Thornton and
Abrams, 1983). If the soil were sludge-
amended, it is conceivable that up to 5 percent
sludge may be ingested in this manner as well.
Therefore, this value accounts for either of
these scenarios, whether forage is harvested or
grazed in the field.
iv. Peed concentration toxic to herbivorous animal
(TA) = 1400 ug/g DW
In sludge applied to soil, Fe II is readily
oxidized to the less available Fe III (see
Section 3, p. 3-5). It is assumed that a simi-
lar conversion readily takes place in sludge
applied over growing forage, once the sludge is
permitted to dry. Therefore, a value for feed
concentration toxic to herbivorous animals will
be chosen based on data for Fe III (i.e.,
FeO[OH]), since this index estimates hazard
from ingested sludge or soil. A dietary Fe
concentration of 1400 Ug/g DW administered as
FeO(OH), was associated with marked adverse
effects on Cu status in cattle (although per-
formance was not affected) (Campbell et al.,
1974). However, if forage were grazed immedi-
ately after liquid sludge application, the
lower value of 477 Ug/g DW based on Fe II might
be more applicable (see Section 3, p. 3-10 and
Section 4, p. 4-12).
d. Index 8 Values
Sludge Application Rate (mt/ha)
Sludge
Concentration 0 5 50 500
Typical
Worst
0.71
0.71
1.0
2.8
1.0
2.8
1.0
2.8
Value Interpretation - Value equals factor by which
expected dietary concentration exceeds toxic concen-
tration. Value > 1 indicates a toxic hazard may
exist for grazing animals.
Preliminary Conclusion - The incidental ingestion of
sludge-amended soil may pose a toxic hazard to graz-
ing animals when sludge containing a high
concentration of Fe is applied.
3-13
-------
E. Effect on Humans
1. Index of Human Toxicity Resulting from Plant Consumption
(Index 9)
a. Explanation - Calculates dietary intake expected to
result from consumption of crops grown on sludge-
amended soil. Compares dietary intake with accept-
able daily intake (ADI) of the pollutant.
b. Assumptions/Limitations - Assumes that all crops are
grown on sludge-amended soil and that all those con-
sidered to be affected take up the pollutant at the
same rate as the most responsive plant(s) (as chosen
in Index 5). Divides possible variations in dietary
intake into two categories! toddlers (18 months to
3 years) and individuals over 3 years old.
c. Data Used and Rationale
i. Index of plant concentration increment caused
by uptake (Index 5)
Index 5 values used are those for a human diet
(see Section 3, p. 3-8).
ii. Background concentration in plant tissue (BP) =
94 yg/g DW
The background concentration value used is for
the plant chosen for the human diet (see
Section 3, p. 3-8).
iii. Daily human dietary intake of affected plant
tissue (DT)
Toddler 74.5 g/day
Adult 205 g/day
The intake value for adults is based on daily
intake of crop foods (excluding fruit) by vege-
tarians (Ryan et al., 1982); vegetarians were
chosen to represent the worst case. The value
for toddlers is based on the FDA Revised Total
Diet (Pennington, 1983) and food groupings
listed by the U.S. EPA (1984). Dry weights for
individual food groups were estimated from
composition data given by the U.S. Department
of Agriculture (USDA) (1975). These values
were composited to estimated dry-weight
consumption of all non-fruit crops.
3-14
-------
iv. Average daily human dietary intake of pollutant
(DI)
Toddler 15,000 Ug/day
Adult 17,400 Ug/day
Sollman (1957 as cited in U.S. EPA, 1976)
reported a range of 7,000 to 35,000 Ug/day in
diets with an average of 16,000 ug/day. Bjorn-
Rasmussen et al. (1974 in TDI, 1981) reported
an average daily intake of 17,400 Ug/g in
males. The daily nutritional requirement for
Fe is 1,000 to 2,000 Ug> but larger quantities
are required in the diet due to poor absorp-
tion. NRC Recommended Daily Allowances (RDAs)
for Fe ranged from 10,000 to 18,000 ug/day
depending on age and sex (NRC, 1980 in TDI,
1981). The RDA for children 1 to 3 years old
(15,000 ug/day) was chosen to represent average
daily intake in toddlers. The average daily
intake for males, 17,400 ug/day, was chosen as
the average daily intake for adults. This
value is within the range of RDA values and
reflects a reported average intake.
v. Acceptable daily intake of pollutant (ADI) =
35,000 Ug/day
No information was available on acceptable
daily intake of Fe. Recommended daily intakes
(RDAs) ranged from 10,000 to 18,000 Ug> depend-
ing on age and sex (NRC, 1980 in TDI, 1981).
The RDA for pregnant and lactating women
includes Fe supplements to the diet of 30 to
60 fng daily. RDAs are considered the minimal
requirement for normal healthy persons and
necessary for the avoidance of Fe deficiency,
anemia, or other manifestations of severe lack
of Fe (TDI, 1981). Diets are reported to range
from 7,000 to 35,000 ug/day by Sollman (1957 in
U.S. EPA, 1976). High incidence of hemochroma-
tosis and siderosis were observed among Bantu
populations where males consumed 50 to
100 mg/day of Fe from beer alone (Bothwell et
al., 1964 in TDI, 1981).
The value of 35,000 ug/day was selected to
represent the high end of the range of normal
daily intake, with the exception of pregnant
and lactating women. This value was
conservatively chosen to avoid problems
associated with chronic excessive intake of Fe.
3-15
-------
d. Index 9 Values
Sludge Application
Rate (mt/ha)
Sludge
Group Concentration 0 5 50 500
Toddler
Typical
Worst
0.43
0.43
0.43
0.43
0.43
0.48
0.48
0.81
Adult Typical 0.50 0.50 0.51 0.64
Worst 0.50 0.51 0.63 1.6
e. Value Interpretation - Value equals factor by which
expected intake exceeds ADI. Value > 1 indicates a
possible human health threat. Comparison with the
null index value at 0 mt/ha indicates the degree to
which any hazard is due to sludge application, as
opposed to pre-existing dietary sources.
f. Preliminary Conclusion - Landspreading of sludge is
not expected to pose a health hazard due to Fe for
humans who consume plants grown in sludge-amended
soil, except possibly for adults when sludge con-
taining a high concentration of Fe is applied at a
high rate.
2. Index of Human Toxicity Resulting from Consumption of
Animal Products Derived from Animals Feeding on Plants
(Index 10)
a. Explanation - Calculates human dietary intake
expected to result from consumption of animal
products derived from domestic animals given feed
grown on sludge-amended soil (crop or pasture land)
but not directly contaminated by adhering sludge.
Compares expected intake with ADI.
b. Assumptions/Limitations - Assumes that all animal
products are from animals receiving all their feed
from sludge-amended soil. The uptake slope of pol-
lutant in animal tissue (UA) used is assumed to be
representative of all animal tissue comprised by the
daily human dietary intake (DA) used. Divides pos-
sible variations in dietary intake into two categor-
ies: toddlers (18 months to 3 years) and
individuals over 3 years old.
3-16
-------
Data Used and Rationale
i. Index of plant concentration increment caused
by uptake (Index 5)
Index 5 values used are those for an animal
diet (see Section 3, p. 3-8).
ii. Background concentration in plant tissue (BP) =
36.3 ug/g DW
The background concentration value used is for
the plant chosen for the animal diet (see
Section 3, p. 3-8).
iii. Uptake slope of pollutant in animal tissue (UA)
= 0.26 Ug/g tissue DW (ug/g feed DW)'1
Standish et al. (1969 in NAS, 1980) reported
uptake of Fe in steers fed diets . containing
FeSO^. Uptake slopes were calculated for
liver, spleen, kidney, heart and muscle.
Spleen tissue had the highest uptake slope but
was not selected for use in the index because
it does not represent tissue normally consumed
by humans. Liver had the second highest uptake
slope and was selected for calculation of the
index since it is a common component of the
human diet. The uptake slope for muscle was
very low. This slope was not chosen because
Standish et al. (1969 in NAS, 1980) noted that.
the increase in muscle tissue concentration of
Fe was not significant. (See Section 4,
p. 4-13.)
iv. Daily human dietary intake of affected animal
tissue '(DA)
Toddler 0.97 g/day
Adult. 5.76 g/day
The FDA Revised Total diet (Pennington, 1983)
lists average daily intake of beef liver fresh
weight for' various age-sex classes. The 95th
percentile of liver consumption (chosen in
order to be conservative) is assumed to be
approximately 3 times the mean values.
conversion to dry weight is based on data from
USDA (1975).
3-17
-------
v. Average daily human dietary intake of pollutant
(DI)
Toddler 15,000 Ug/day
Adult 17,400 Ug/day
See Section 3, p. 3-15.
vi. Acceptable daily intake of pollutant (ADI) =
35,000 Ug/day
See Section 3, p. 3-15.
Index 10 Values
Group
Sludge
Concentration
Sludge Application
Rate (mt/ha)
5 50 500
Toddler
Typical
Worst
0.43
0.43
0.43
0.43
0.43
0.43
0.43
0.43
Adult
Typical
Worst
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
e.
f.
Value Interpretation - Same as for Index 9.
Preliminary Conclusion - The consumption of animal
products from animals that have grazed plants grown
in sludge-amended soil is not expected to pose a
health threat due to Fe for humans.
3. Index of Human Toxicity Resulting from Consumption of
Animal Products Derived from Animals Ingesting Soil
(Index 11)
a. Explanation - Calculates human dietary intake
expected to result from consumption of animal prod-
ucts derived from grazing animals incidentally
ingesting sludge-amended soil. Compares expected
intake with ADI..
b. Assumptions/Limitations - Assumes that all animal
products are from animals grazing sludge-amended
soil, and that all animal products consumed take up
the pollutant at the highest rate observed for
muscle of any commonly consumed species or at the
rate observed for beef liver or dairy products
(whichever is higher). Divides possible variations
in dietary intake into two categories: toddlers
(18 months to 3 years) and individuals over three
years old.
3-18
-------
c. Data Used and Rationale
i. Animal tissue = Beef liver
Section 3, p. 3-17.
ii. Background concentration of pollutant in soil
(BS) = 20,000 Ug/g DW
See Section 3, p. 3-2.
iii. Sludge concentration of pollutant (SC)
Typical 28,000 Ug/g DW
Worst 78,700 ug/g DW
See Section 3, p. 3-1.
iv. Fraction of animal diet assumed to be soil (GS)
= 5%
See Section 3, p. 3-12.
v. Uptake slope of pollutant in animal tissue (UA)
= 0.26 ug/g tissue DW (ug/g feed DW)~1
See Section 3, p. 3-17.
vi. Daily human dietary intake of affected animal
tissue (DA)
Toddler 0.97 g/day
Adult 5.76 g/day
See Section 3, p. 3-17.
vii. Average daily human dietary intake of pollutant
(DI)
Toddler 15,000 Ug/day
Adult 17,400 ug/day
See Section 3, p. 3-15.
viii. Acceptable daily intake of pollutant (ADI) =
35,000 Ug/day
See Section 3, p. 3-15.
3-19
-------
Index 11 Values
Sludge Application
Rate (mt/ha)
Sludge
Group Concentration 0 5 50 500
Toddler
Adult
Typical
Worst
Typical
Worst
0.44
0.44
0.54
0.54
0.44
0.46
0.56
0.67
0.44
0.46
0.56
0.67
0.44
0.46
0.56
0.67
e. Value Interpretation - Same as for Index 9.
f. Preliminary Conclusion - The consumption of animal
products from animals that have ingested sludge-
amended soils is not expected to pose a health
threat due to Fe for humans.
Index of Human Toxicity from Soil Ingestion (Index 12)
a. Explanation - Calculates the amount of pollutant in
the diet of a child who ingests soil (pica child)
amended with sludge. Compares .this amount with ADI.
b. Assumptions/Limitations - Assumes that the pica
child consumes an average of 5 g/day of sludge-
amended soil. If an ADI specific tor a child is not
available, this index assumes that the ADI for a
10 kg child is the same as that for a 70 kg adult.
It is thus assumed that uncertainty factors used in
deriving the ADI provide protection for the child,
taking into account the smaller body size and any
other differences in sensitivity.
c. Data Used and Rationale
i. Index of soil concentration increment (Index 1)
See Section 3, p. 3-2.
ii. Sludge concentration of pollutant (SC)
Typical 28,000 Ug/g DW
Worst 78,700 Ug/g DW
See Section 3, p. 3-1.
iii. Background concentration of pollutant in soil
(BS) = 20,000 ug/g DW
See Section 3, p. 3-2.
3-20
-------
iv. Assumed amount of soil in human diet (DS)
d.
Pica child
Adult
5 g/day
0.02 g/day
The value of 5 g/day for a pica child is a
worst-case estimate employed by U.S. EPA's
Exposure Assessment Group (U.S. EPA, 1983).
The value of 0.02 g/day for an adult is an
estimate from U.S. EPA (1984).
v. Average daily human dietary intake of pollutant
(DI)
Toddler 15,000 ug/day
Adult 17,400 Ug/day
See Section 3, p. 3-15.
vi. Acceptable daily intake of pollutant (ADI) =
35,000 Ug/day
See Section 3, p. 3-15.
Index 12 Values
Sludge Application
Rate (mt/ha)
Group
Toddler
Adult
Sludge
Concentration
Typical
Worst
Typical
Worst
0
3.3
3.3
0.51
0.51
5
3.3
3.3
0.51
0.51
50
3.3
3.5
0.51
0.51
500
3.5
5.0
0.51
0.52
Pure
Sludge
4.4
12
0.51
0.54
e. Value Interpretation - Same as for Index 9.
f. Preliminary Conclusion - Ingestion of sludge-amended
soil or pure sludge by toddlers may increase the
health hazard due to Fe, above the hazard posed by
ingestion of unamended soil. This increase may be
substantial when sludge containing a high concentra-
tion of Fe is applied at a high rate. For adults,
ingestion of sludge-amended soil or sludge is not
expected to pose a health hazard due to Fe.
5. Index of Aggregate Human Toxicity (Index 13)
a. Explanation - Calculates the aggregate amount of
pollutant in the human diet resulting from pathways
described in Indices 9 to 12. Compares this amount
with ADI.
3-21
-------
b. Assumptions/Limitations - As described for Indices 9
to 12.
c. Data Used and Rationale - As described for Indices 9
to 12.
d. Index 13 Values
Sludge Application
Rate (mt/ha)
Sludge
Group Concentration 0 5 50 500
Toddler
Typical
Worst
3.3
3.3
3.3
3.3
3.3
3.6
3.6
5.4
Adult Typical 0.55 0.57 0.59 0.71
Worst 0.55 0.69 0.81 1.7
Value Interpretation - Same as for Index 9.
Preliminary Conclusion - The aggregate amount of Fe
in the toddler diet resulting from landspreading of
sludge may slightly increase the health hazard due
to Fe above the risk posed by the acceptable daily
intake of Fe. For adults, a health hazard due to
the aggregate amount of Fe in the diet is only
expected when sludge containing a high concentration
of Fe is landspread at a high rate.
II. LANDFILLING
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at Chis time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
III. INCINERATION
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves' the right
to conduct such an assessment for this option in the future.
IV. OCEAN DISPOSAL
Based on the recommendations of the experts at the OWRS meetings
(April-May, ,1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
3-22
-------
SECTION 4
PRELIMINARY DATA PROFILE FOR IRON IN MUNICIPAL SEWAGE SLUDGE
I. OCCURRENCE
A. Sludge
1. Frequency of Detection
100% - based on ubiquitous nature
use in wastewater treatment
2. Concentration
and
Range 1,000
Source of Sludge
Janesville, WI
Fond du Lac, WI
Wisconsin Rapids, WI
Waukesha, WI
Stillwater, MN
Washington, D.C.
Anderson, IN
Crawfordsville, IN
Kokomo, IN
Lebanon, IN
Logansport, IN
Noblesville, IN
Peru, IN
Tipton, IN
Median value for 14 cities
Worst value for 14 cities
to 37,000 ppm (DW)
Fe Concentration
-------
Soil - Unpolluted
1. Frequency of Detection
Fe is the fourth most abundant
element in the earth's crust;
ubiquitous
2. Concentration
Range 7000 to 42,000 ppm
4700 to 43,000 ppm - range of
geometric means for different
soil types
20,000 geometric mean - western States
15,000 geometric mean - eastern States
Water - Unpolluted
1. Frequency of Detection
Assumed 100% due to ubiquitous nature
2. Concentration
a. Freshwater
<_ 1 Ug/L in true solution
in surface water
2 to 200 Ug/L reported ranges
0.04 to 0.67 mg/L
b. Seawater
0.1 to 3.0 ug/L
0.01 mg/L
c. Drinking Water
0.3 mg/L criterion for domestic
water supplies
TDI, 1981
(p. 184)
Jackson, 1964 in
TDI, 1981
(p. 187)
Connor and
Shacklette,
1975 in TDI,
1981 (p. 187)
Shacklette et
al., 1971 in
TDI, 1981
(p. 187)
TDI, 1981
(p. 184)
Hem, 1970
(p. 12)
Berner, 1970
in TDI, 1981
(p. 193)
Hem, 1970
(p. 11)
U.S. EPA, 1976
(p. 78)
4-2
-------
1.8 mg/L in spring water and
3.4 mg/L in distilled water,
taste of Fe detected
Air
1. Frequency of Detection
Assumed 100% due to ubiquitous nature
2. Concentration
a. Urban
14 Ug/m-* (industrial sector
of Chicago)
1580 ng/m-3 mean for urban
location in U.S.
b. Rural
50 ng/m3 (Colstrip, MN)
Pood
1. Total Average Intake
6 mg/1000 kcal (4.9 to 6.3 mg range) -
in typical western diet
NRC Recommended Daily Allowances
Children, 1 to 3 yrs 15,000 Ug/day
Males, 11 to 18 yrs 18,000 Ug/day
Males, 19 to 51+ yrs 10,000 Ug/day
Females, 11 to 50 yrs 18,000 ug/day
Females, 51+ yrs 10,000 ug/day
30 to 60 mg supplemental Fe required
daily for pregnant and lactating
women
12 mg Fe per day in typical vegetarian
diet
17.4 mg Fe per day in diet of typical
men
Cohen et al.,
1960 in U.S.
EPA, 1976 -
(p. 79)
TDI, 1981
(p. 185)
TDI, 1981
(p. 194)
TDI, 1981
(p. 185)
TDI, 1981
(p. 416)
NRC, 1980 in
TDI, 1981
(p. 412)
NRC, 1980 in
TDI, 1981
(p. 412)
TDI, 1981
(p. 418)
Bjorn-Rasmussen
et al., 1974 in
TDI, 1981
(p. 566)
4-3
-------
1 to 2 mg daily nutritional require-
ment but larger quantities required
due to poor absorption. Diets contain
7 to 35 mg per day and average 16 mg.
2. Concentration
Sollman, 1957
in EPA, 1976
(p. 79)
Food
Fe concentration
ppm (DW)
Source
Barley
Citrus, pulp
Corn grain
Oats
Rice bran
Wheat bran
Wheat grain
Fe Content of
50
200
200
70
190
150
50
TDI, 1981 (p. 326)
TDI, 1981 (p. 326)
TDI, 1981 (p. 326)
TDI, 1981 (p. 326)
TDI, 1981 (p. 326)
TDI, 1981 (p. 326)
TDI, 1981 (p. 326)
Some Representative Foods TDI , 1981
mg Fe/100
Kcal
(p. 417)
mg Fe/lOOg
Edible Portion
Liver, calf
Lettuce
Green beans
Eggs
Ground beef
Chicken, dark meat
Chicken, white meat
Wheat flour, refined
Milk
Sugar
5.4
7.8
2.4
1.4
1.4
1.0
0.8
0.2
Trace
14.2
1.4
0.6
2.3
3.2
1.7
1.3
0.8
Trace
0.1
II. HUMAN EFFECTS
A. Ingestion
1. Carcinogenicity
a. Qualitative Assessment
Cancer of the esophagus has been
found to be associated with both
Fe deficiency and Fe overload,
MacPhail et al.,
1979 in TDI,
1981 (p. 550)
4-4
-------
but no causal relationship has
been established.
b. Potency
None demonstrated for ingestion
route.
c. Effects
Liver carcinoma occurs in about
15% of subjects with idiopathic
hemochromatosis. Hemochromatosis
may increase the risk of primary
tumor development elsewhere in
the body.
Chronic Toxicity
a. ADI
No ADI has been established for
Fe.
Finch and Finch,
1955
b. Effects
^100 rag Fe/day in male Bantu
population over many years
results in siderosis. Fe derives
from beer brewed in iron
containers.
^275 mg Fe/day for j>10 years
has resulted in cases of
hemochromatosis.
Absorption Factor
Nonheme - Fe
Heme - Fe
1-10%
10-25%
Ferric iron absorption is greatly
increased when given with brandy or
whiskey to normal fasting subjects.
Existing .Regulations
Water Quality Criteria
(July 1976) = 0.3 mg/L
Bothwell et al.,
1965 in TDI,
1981 (p. 511)
TDI, 1981
(p. 516)
TDI, 1981
(p. 397)
Charlton et al.,
1964 in TDI,
1981
U.S. EPA, 1976
4-5
-------
B. Inhalation
1. Carcinogenicity
a. Qualitative Assessment
No carcinogenicity has been TDI , 1981
demonstrated for ferric oxides. (p. 556)
b. Potency
None demonstrated for inhalation
route.
c. Effects
No cancers were found to be U.S. EPA, 1982
induced in inhalation exposure of (p. 19)
animals by iron oxide, although
the latter does act as a carcino-
gen in the presence of known
carcinogens .
2. Chronic Toxicity
a. Inhalation Threshold or MPIH
See below, "Existing Regulations"
b. Effects
Exposure to levels of ferric oxide TDI, 1981
above the threshold values has (p. 541)
been known to cause lung irritation.
3. Absorption Factor
Data not immediately available.
4. Existing Regulations
5 mg/m3 TWA iron oxide fume (Fe203) ACGIH, 1982
10 mg/m3 STEL as Fe
III. PLANT EFFECTS
A. Pbytotoxicity
1. Soil Concentration
>400 ppm soluble Fe associated with Nhung and
toxicity to rice; >500 ppm highly Ponnamperuma ,
toxic 1966 in Foy
4-6
-------
100 to 500 ppm soluble Fe produced Fe
toxicity in rice
Fe poses little hazard to crop
production and plant accumulation
when sludge is applied to soils
because of its low solubility. As
a result, it has low availability to
plants.
50 and 100 t/ha of sludge with
122,000 mg/kg Fe increased yield
of fodder rape over controls.
2. Tissue Concentration
See Table 4-1.
B. Uptake
et al., 1978
(p. 532)
Tanaka et al.,
1966 in Foy
et al., 1978
(p. 533)
CAST, 1976
(pp. 2 and 24)
Narwal et al.,
1983 (p. 361)
Plant
Concentration
Part ppm (DW)
Source
Corn
Peanut
Rice
Sorghum
Cabbage
Cereal grains
grain
leaf
leaf
plant
leaf
grain
30-50
50-300
89-193
160-250
40-100
30-60
TDI,
TDI,
TDI,
TDI,
TDI,
NAS,
1981
1981
1981
1981
1981
1980
(p.
(p-
(p.
(p.
(p.
(p.
323)
323)
323)
323)
323)
243)
100 to 700 ppm in cultivated grasses
200 ppm alfalfa meal
100 to 200 pg/g in upper leaves of
soybeans prior to pod set
See Table 4-2.
NAS, 1980
(p. 243)
TDI, 1981
(p. 326)
TDI, 1981
(p. 323)
4-7
-------
IV. DOMESTIC ANIMAL AND WILDLIFE EFFECTS
A. Toxicity
"Evidence for Fe toxicity in domestic or
farm animals, or animals living in their
natural habitat, is practically nonexistent".
See Table 4-3.
B. Uptake
See Table 4-4.
V. AQUATIC LIFE EFFECTS
A. Toxicity
1. Freshwater
TDI , 1981
a. Acute
Mayfly larvae
Mosquitofish
Dapthnia magna
Amphipods
b. Chronic
Fe2* 320 ug/L
Fe2* 102,900 Ug/L
Fe3* 9,600 Ug/L
Fe3* 100,000 Ug/L (suspension)
U.S. EPA, 1982
(p. 23-26)
1110 Ug/L
9690 Ug/L
<1870 Ug"/L
<4120
Coho salmon Fe3"1"
Brook trout Fe3*
Fathead minnows Fe3*
Amphipods Fe3*
There is no final freshwater acute or-
chronic value for Fe because the mini
mum data based requirements were not
met.
Saltwater
Acute
Worm species
Mummichog
Mummichog
Mummichog
Fe2* 100,000 Ug/L
Fe2* (ferric chloride) 26,900 Ug/L
Fe3* (ferric ammonium
chloride) 31,500 Ug/L
Fe2* (ferrous ammonium
sulfate) " 110,800 ug/L
No final saltwater acute value could
be calculated.
4-8
-------
b. Chronic
Acceptable chronic toxicity values were
not found for any saltwater animal.
B. Uptake
Data not immediately available.
VI. SOIL BIOTA EFFECTS
A. Toxicity
Data not immediately available.
B. Uptake
Fe concentration (ug/g) in tissues and Helmke et al.,
casts of earthworms grown on sludge-amended 1979 (pp. 324 to
soil (20,800 Ug/g Fe in soil, 325)
11,600 Ug/g Fe in sludge). Wet or dry
weight not specified. Since there was no
clear relationship between applied Fe and
Fe in earthworms, an uptake slope could
not be calculated.
Fe 1971a 1972a 1973a
Application
Rate worms casts worms casts worms casts
Control
174 kg/ha
348 kg/ha
696 kg/ha
730
1190
-
2010
23,000
23,500
-
23,300
1860
5300
390
560
21,900
21,000
19,500
20,000
500
750
410
380
20,800
19,200
19,300
18,500
a Date of sludge application. Sampling conducted in 1975 or
1976.
VII. PHYSICOCHEMICAL DATA FOR ESTIMATING FATE AND TRANSPORT
Atomic weight: 55.847 CRC Handbook of
Melting point: 1535°C Chemistry and
Boiling point: 2750°C Physics, 1976
Specific gravity: 7.86 at 20°C (p. B-119)
Solubility in water: insoluble
4-9
-------
TABLE 4-1. PHYTOTOXICITY OF IRON
Chemical
Plant/tissue Form Applied Soil pH
Rice seedlings Fe** 5.6
Control Tissue
Concentration
(Mg/g DW)
NRa
Experimental
Soil Concentration
(Mg/g DW)
490 mg/Lb»e
Experimental Tissue
Concentration
(Mg/g DW) Effect
NR
Death of rice seedlings
References
Nhung
and Ponnamperuma ,
1966 in Poy et al., 1978
Pe+* 5.6
Fe*+ 5.6
Fe** acid
Fe** acid
Fe** acid
-O
^ Tobacco/leaf Fe*+ NR
O
Rice/root Fe** 3.7
NR
Soybean/top Fe+* NR
. Alfalfa/top Iron 6.6
tailings
(field)
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
>500 mg/Lc»e
>400 mg/Lc»e
730 mg/Le
365 mg/Ld'e
655 mg/Le
NR '
100 mg/Le
500 mg/Le
NR
2134
NR
NR
NR
NR
NR
450 - 1126°
NR
NR
1320
1206
Highly toxic to rice
Toxicity in rice
Killed rice plants 1 day
after transplanting
Toxicity symptoms
Toxicity symptoms
Plant injury
Decreased leaf strength
Plant toxicity
Plant toxicity
Growth limitations
No observed effects on
growth and development'
Rhoads
et al.
Tanaka
Foy et
Brown
Foy et
, 1971 in Foy
, 1978
et al., 1966 in
al., 1978
and Jones, 1977 in
al., 1978
Shetron. 1979
a NR - Not reported.
b Associated aluminum concentration 68 Mg/g.
c Associated aluminum concentrations 25 Mg/g'
™ At planting.
e Refers to concentration of soluble Fe in soil solution or culture medium.
* Study did not report analysis of yield.
-------
TABLE 4-2. UPTAKE OF IRON BY PLANTS
Plant/tissue
Plainsman sorghum/tops
Kafir sorghum/tops
Lettuce/leaf
Beet/tubers
Wheat/grain
Tomato/fruit
Lettuce/leaf
Turnip/greens
Chemical Form Range (N) of Control Tissue
Applied Soil Application Rates Concentration Uptakeb
(study type) pH ( kg/ha )a (pg/6 DW) Slope References
Fe as FeSO^ (pot) 7.6 0 - 736 (2) 112
Fe as FeS04 (pot) 7.6 0 - 736 (2) 107
Primary digested 6.4 3075 - 4360 (3)c 113
sludge and
milorganite (pot)
Primary digested 6.4 3075 - 4360 (3)c 128
sludge and
milorganite (pot)
Combined liquid digested NR (loamy 0 - 1400 (3) 36.3
sludge (field)6 sand)
Anaerobically digested 5.3 0 - 9870 (5) 17
dried sludge (field)
Anaerobically digested .5.3 0 - 4442 (4) 94
dried sludge (field)
Secondary digested 5.6 0 - 1116 (3) 377
sludge (field)
0.065 Puller and Lanspa, 1975
0.018 Puller and Lanspa, 1975
0.0075d John and Van Laerhoven, 1976
0.0112d John and Van Laerhoven, 1976
0.0057 Sabey and Hart, 1975
0.0025 Dowdy and Larson, 1975
0.0077 Dowdy and Larson, 1975
0.27 Miller and Boswell, 1979
(p. 1362)
a N = Number of application rates, including control.
b Slope = y/x: x = kg Fe applied/ha; y = pg Fe/g plant tissue (dry weight).
c Unit is pg Fe/g soil, where Fe is IN HNOi - extractable, not total. Total Fe not reported.
Slope is computed assuming 1 MR/8 = 2 kg/ha to convert soil concentration to application rate,
e Sludge consisted of 502 anaerobically digested primary sludge and 50% aerobically digested primary sludge.
-------
TABLE 4-3. TOXICITY OF IRON TO DOMESTIC ANIMALS AND WILDLIFE
I
NJ
Feed Water Daily
Chemical Concentration Concentration Intake
Species (N)a Form Fed (pg/g DW) (mg/L) (mg/kg DW)
Swine (6) FeS04 3000 NRC NR
FeSO^ 4000 NR NR
Chicken (20) FeS04 400 NR NR
FeSO^ 800 NR NR
Cattle (6) FeSOA 477 NR NR
FeS04 1677 NR NR
Cattle (8) Iron citrate 100 NR ' NR
Iron citrate 500 - 1000 NR NR
Iron citrate 2500 NR NR
Cattle (8) FeO(OH) 1400 NR 30
Duration
of Study (days) Effect
56
56
28
28
84
84
98
NR
NR
210
No Effect
Reduced growth
No effect
Reduced growth
Slight decrease in
gains and food conversion
Significant reductions in
growth and feed intake
No adverse effect
Trend toward poorer
performance (weight
gain, feed consumption)
Significant reduction
in feed intake and
daily weight gain
Marked depression of
liver and blood Cu,
caeruloplasmin and amine
oxidase. No effect on
performance
References'1
0' Donovan et al., 1963
0' Donovan et al., 1963
NcGhee et al., 1965
McGhee et al., 1965
Standish et al., 1969
Standish et al., 1969
Standish et al., 1971
Koong et al., 1970
Koong et al., 1970
Campbell et al., 1974
a N = Number of animals/treatment group.
D Source of all information in table is from NAS, 1980 (p. 244 and pp. 249 to 252).
c NR = Not reported.
-------
TABLE 4-4. UPTAKE OF IRON BY DOMESTIC ANIMALS AND WILDLIFE
Species(N)*
Chemical
Form Fed
Range (N)b
of Feed Tissue
Concentration
DW)
Tissue
Analyzed
Control Tissue
Concentration
(Mg/g DW)C
Uptake0 'd
Slope
References
i
OJ
Steers
0 - 1600 (2)
Liver
185
0.26 Standish et al., 1969 in
NAS, 1980
FeS04
FeS04
FeS04
FeS04
0 -
0 -
0 -
0 -
1600 (2)
1600 (2)
1600 (2)
1600 (2)
Spleen
Kidney
Heart
Muscle
1219
315
291
91
4.8
0.059
0.024
O.i
a N = Number of animals/treatment group.
)04
" N = Number of feed concentrations, including control.
c When tissue values were reported as wet weight, unless otherwise indicated a moisture content of 771 was assumed for kidney, 701 for liver and
72X for muscle. ,
d Slope = y/x: x = Mg/g feed (DW)j y = ug/g tissue (DW).
-------
SECTION 5
REFERENCES
American Conference of Governmental and Industrial Hygienists. 1982.
Threshold Limit Values for Chemical Substances in Work Air Adopted
by ACGIH for 1982. Cincinnati, OH.
Asghar, M., and Y. Kanehiro. 1981. The Fate of Applied Iron and
Manganese in an Oxigol and an Ultisol from Hawaii. Soil Sci.
131:53-55.
Berner, R. 1970. Iron-Abundance in Natural Waters. In; Wedepohl,
K. H. (ed.), Handbook of Geochemistry. Springer-Verlag. New York,
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Bertrand, J. E., M. C. Lutrick, G. T. Edds, and R. L. West. 1981.
Metal Residues .in Tissues, Animal Performance and Carcass Quality
with Beef Steers Grazing Pensacola Bahiagrass Pastures Treated with
Liquid Digested Sludge. J. Ani. Sci. 53:1.
Bjorn-Rasmussen, E., et al. 1974. Food Iron Absorption in Man:
Applications of the Two-Pool Extrinsic Tag Method to Measure Heme
and Nonheme Iron Absorption from the Whole Diet. J. Clin. Invest.
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Boswell, F. C. 1975. Municipal Sewage Sludge and Selected Element
Applications to Soil: Effect on Soil and Fescue. J. Environ.
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Bothwell, T. H., et al. 1964. Iron Overload in Bantu Subjects:
Studies on the Availability of Iron in Bantu Beer. Am. J. Clin.
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Bothwell, T. H., et al. 1965. Oral Iron Overload. S. Afr. Med. J.
39:892. (As cited in TDI, 1981.)
Brown, J. C., and W. E. Jones. 1977. Manganese and Iron Toxicities
Dependent on Soybean Variety. Commun. Soil Sci. Plant. Anal.
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Campbell, A. G., M. R. Coup, W. H. Bishop, and D. E. Wright. 1974.
Effect of Elevated Iron Uptake on the Copper Status of Grazing
Cattle. N. Z. J. Agric. Res. 17:393-399.
Chaney, R. L., and C. A. Lloyd. 1979. Adherence of Spray-Applied
Liquid Digested Sewage Sludge to Tall Fescue. J. Environ. Qual.
8(3):407-411.
Charlton, et al. 1964. Effect of Alcohol on Iron Absorption. Br. Med.
Jour. 2:1427. (As cited in TDI, 1981.)
5-1
-------
Cohen, J. M., et al. 1960. Taste Threshold Concentrations of Metals in
Drinking Water. Jour. Amer. Water Works Assn. 52:660. (As cited
in U.S. EPA, 1976.)
Connor, J. J. and H. T. Shacklette. 1975. Background Geochemistry of
Some Rocks, Soils, Plants, and Vegetables in the Coterminous United
States. Geological Survey Professional Paper. 574-F. U.S.
Government Printing Office. Washington, D.C. (As cited in TDI,
1981.)
Council for Agricultural Science and Technology. 1976. Application of
Sewage Sludge to Cropland. Appraisal of Potential Hazards of the
Heavy Metals to Plants and Animals. EPA 430/9-76-013. U.S.
Environmental Protection Agency, Washington, D.C.
CRC Handbook of Chemistry and Physics. 1976. 57th Edition. CRC Press,
Cleveland, OH.
Cunningham, J. D., D. R. Keeney, and J. A. Ryan. 1975. Yield and Metal
Composition of Corn and Rye Grown on Sewage-Sludge Amended Soil.
J. Environ. Qual. 4(4):448-454.
Dowdy, R. H., and W. E. Larson. 1975. The Availability of Sludge-Borne
Metals to Various Vegetable Crops. J. Environ. Qual. 4(2):278-282.
Finch, S. C., and C. A. Finch. 1955. Idiopathic Hemochromatosis, An
Iron Storage Disease. A. Iron Metabolism in Hemochromatosis.
Medicine. 34:381. (As cited in TDI, 1981.)
Foy, C. D., R. L. Chaney, 'and M. C. White. 1978. The Physiology of
Metal Toxicity in Plants. Ann. Rev. Plant. Physiol. 29:511-66.
Fuller, W. H., and K. Lanspa. 1975. Uptake of Iron and Copper by
Sorghum from Mine Trailings. J. Environ. Qual. 4(3):417-422.
Fuller, W. 1977. Movement of Selected Metals, Asbestos, and Cyanide in
Soil: Applications to Waste Disposal Problems. Prepared for U.S.
EPA under Contract No. 68-03-0208. EPA 600/2-77-020. Cincinnati,
OH. April.
Furr, A. K., G. S. Stoewsand, C. A. Bache, and D. J. Lisk. 1976. Study
of Guinea Pigs Fed Swiss Chard Grown on Municipal Sludge-Amended
Soil. Arch. Environ. Health. March/April: 87-91.
Helmke, P. A., W. P. Robarge, R. L. Korotev, and P. J. Schomberg. 1979.
Effect of Soil-Applied Sewage Sludge on Concentrations of Elements
in Earthworms. J. Environ. Qual. 8(3):322-327.
Hem, ' J. D. 1970. Study and Interpretation of the Chemical
'Characteristics of Natural Water. Geological Survey Water-Supply
Paper. 1473. U.S. Government Printing Office, Washington, D.C.
5-2
-------
Jackson, M. L. 1964. Chemical Composition of Soils. In; Bear, E. E.
(ed.), Chemistry of the Soil. American Chem. Soc. Monograph Series
No. 160. Rheinhold Publ. Corp. New York, NY. (As cited in TDI,
1981.)
John, M. K., and C. J. Van Laerhoven. 1976. Effect of Sewage Sludge
Composition, Application Rate, and Lime Regime on Plant
Availability of Heavy Metals. J. Environ. Qual. 5(3):246-251.
Koong, L. J., M. B. Wise, and E. R. Barrick. 1970. Effect of Elevated
Dietary Levels of Iron on the Performance and Blood Constituents of
Calves. J. Ani. Sci. 31:422.
MacPhail, A. P., et al. 1979. Changing Patterns of Dietary Iron
Overload in Black South Africans. Am. Jour. Clin. Nutr. 32:1272.
(As cited in TDI, 1981.)
McGhee, F., C. R. Greger, and J. R. Couch. 1965. Copper and Iron
Toxicity. Poult. Sci. 44:310.
Miller, J., and F. C. Boswell. 1979. ' Mineral Content of Selected
Tissues and Feces of Rats Fed Turnip Greens Grown on Soil Treated
with Sewage Sludge. J. Agric. Food Chem. 27(6):1361-65.
Narwal, R. P., B. R. Singh, and A. R. Panhwar. 1983. Plant
Availability of Heavy Metals in a Sludge-Treated Soil: I. Effect
of Sewage Sludge and Soil pH on the Yield and Chemical Composition
of Rape. J. Env. Qual. 12(3):358-365.
National Academy of Sciences. 1980. Mineral Tolerances of Domestic
Animals. National Research Council Subcommittee on Mineral Toxicity
in Animals. Washington, D.C.
National Research Council. 1979. Iron. University Park Press,
Baltimore, MD.
National Research Council. 1980. Food and Nutrition Board. Revised
, Edition of Recommended Daily Allowances of Foods - Iron. National
Academy of Sciences, Washington, D.C. (As cited in TDI, 1981.)
Nhung, M. T. M., and F. N. Ponnamperuma. 1966. Effects of Calcium
Carbonate, Manganese Dioxide, Ferric Hydroxide, and Prolonged
Flooding, Chemical and Electrochemical Changes and Growth of Rice
in a Flooded Acid Sulfate Soil. Soil. Sci. 102:29-41. (As cited
in Foy et al., 1978.)
O'Donovan, P. B., R. A. Pickett, M. P. Plumlee, and W. M. Beeson. 1963.
Iron Toxicity in the Young Pig. J. Ani. Sci. 22:1075.
Pennington, J. A. T. 1983. Revision of the Total Diet Study Food Lists
and Diets. J. Am. Diet. Assoc. 82:166-173.
Rhoads, F. M. 1971. Relations Between Fe in Irrigation Water and Leaf
Quality of Cigar Wrapper Tobacco. Agron. J. 63:938-40.
5-3
-------
Ryan, J. A., H. R. Pahren, and J. B. Lucas. 1982. Controlling Cadmium
in the Human Food Chain: A Review and Rationale Based on Health
Effects. Environ. Res. 28:251-302.
Sabey, B. R., and W. E. Hart. 1975. Land Application of Sewage Sludge:
I. Effect on Growth and Chemical Corporation of Plants. J.
Environ. Qual. 4(2):252-256.
Shacklette, H. T., et al. 1971. Elemental Composition of Superficial
Materials in the Coterminous United States. U.S. Geological
Society Professional Paper 574-D. U.S. Government Printing Office,
Washington, D.C. 71 pp.
Shetron, S. G. 1979. Chemical Composition of Alfalfa (Medicago sativa
L.) Grown on Iron and Copper Mine Mill Wastes. U.S. Fish and
Wildlife Service, Wildlife Needs in Eastern U.S. Symposium, WV.
NTIS PB 79-05830. pp. 311-319.
Sollman, T. M. 1957. A Manual of Pharmacology. 8th Ed. W. B.
Saunders Co. Philadelphia, PA.
Sommers, L. E., D. W. Nelson, and K. J. Yost. 1976. Variable Nature of
Chemical Compositon of Sewage Sludges. J. Environ. Qual.
5(3):303-306.
Standish, J. F., C. B. Ammerman, C. F. Simpson, F. C. Neal, and A. Z.
Palmer. 1969. Influence of Graded Levels of Dietary Iron, as
Ferrous Sulfate, on Performance and Tissue Mineral Composition of
Steers. J. Ani. Sci. 29:496.
Standish, J. F., C. B. Ammerman, A. Z. Palmer, and C. F. Simpson. 1971.
Influence of Dietary Iron and Phosphorus on the Performance, Tissue
Mineral Composition and Mineral Absorption in Steers. J. Ani. Sci.
33:171.
TDI, Inc. 1981. Multimedia Criteria for Iron and Compounds. Draft
Prepared for EPA. Cincinnati, OH.
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in the Development of Iron Symptoms in the Rick Plant. Soil Sci.
Plant Natr. 19:173-82. (As cited in Foy et al., 1978.)
Thornton, I., and P. Abrams. 1983. Soil Ingestion - A Major Pathway of
Heavy Metals into Livestock Grazing Contaminated Land. Sci. Total
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Agricultural Handbook No. 8.
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5-4
-------
U.S. Environmental Protection Agency. 1982. Draft Interim Criterion
Statement: Iron. Ambient Water Quality Criterion for the
Protection of Human Health. Internal Review CIN-82-D008.
Environmental Criteria and Assessment Office, Cincinnati, OH.
U.S. Environmental Protection Agency. 1983. Assessment of Human
Exposure to Arsenic: Tacoma, Washington. Internal Document.
OHEA-E-075-U. Office of Health and Environmental Assessment,
Washington, D.C. July 19.
U.S. Environmental Protection Agency. 1984. Air Quality Criteria for
Lead. External Review Draft. EPA 600/8-83-028B. Environmental
Criteria and Assessment Office, Research Triangle Park, NC.
September.
5-5
-------
APPENDIX
PRELIMINARY HAZARD INDEX CALCULATIONS FOR IRON
IN MUNICIPAL SEWAGE SLUDGE
I. LANDSPREADING AND DISTRIBUTION- AND-MARKETING
A. Effect on Soil Concentration of Iron
1. Index of Soil Concentration Increment (Index 1)
a. Formula
T j , _ (SC x AR) + (BS x MS)
IndeX : ~ BS (AR + MS)
where:
SC = Sludge concentration of pollutant
(Ug/g DW)
AR = Sludge application rate (mt DW/ha)
BS = Background concentration of pollutant in
soil (ug/g DW)
MS = 2000 mt DW/ha = Assumed mass of soil in
upper 15 cm
b. Sample calculation
_ _ (28000 ug/g DW x 5 mt/ha) •*• (20000 Ug/g DW x 2000 mt/ha)
20000 ug/g DW (5 mt/ha + 2000 mt/ha)
B. Effect on Soil Biota and Predators of Soil Biota
1. Index of Soil Biota Toxicity (Index 2)
a. Formula
Ii x BS
Index 2 =
where:
II = Index 1 = Index of soil concentration
increment (unitless)
BS = Background concentration of pollutant in
soil (ug/g DW)
TB = Soil concentration toxic to soil biota
(pg/g DW)
b. Sample calculation - Values were not calculated due
to lack of data.
A-l
-------
2. Index of Soil Biota Predator Toxicity (Index 3)
a. Formula
(II - 1)(BS x UB) + BB
Index 3 = —
whereJ
II = Index 1 = Index of soil concentration
increment (unitless)
BS = Background concentration of pollutant in
soil (Ug/g DW)
UB = Uptake slope of pollutant in soil biota
(Ug/g tissue DW [Ug/g soil DW]"1)
BB = Background concentration in soil biota
(Ug/g DW)
TR = Feed concentration toxic to predator (ug/g
DW)
b. Sample calculation - Values were not calculated due
to lack of data.
C. Effect on Plants and Plant Tissue Concentration
1. Index of Phytotoxicity (Index 4)
a. Formula
IT x BS
Index 4 = 'Tp
where:
!]_ = Index 1 = Index of soil concentration
increment (unitless)
BS = Background concentration of pollutant in
soil (ug/g DW) y
TP = Soil concentration toxic to plants (ug/g
DW)
b. Sample calculation - Values were not calculated due
to lack of data.
2. Index of Plant Concentration Increment Caused by Uptake
(Index 5)
a. Formula
(Ii - 1) x BS
Index 5 = —= x CO x UP + 1
BP
A-2
-------
where:
II = Index 1 = Index of soil concentration
increment (unitless)
BS = Background concentration of pollutant in
soil (ug/g DW)
CO = 2 kg/ha (jag/g)"* = Conversion factor
between soil concentration and application
rate
UP = Uptake slope of pollutant in plant tissue
(Ug/g tissue DW [kg/ha]"1)
BP = Background concentration in plant tissue
(Ug/g DW)
Sample calculation
- (1.000997-1) x 2QOQO Ug/g DW 2 kg/ha
— ->/•-» / _,, x / ..,
36.3 ug/g DW ug/g soil
0.0057 ug/g tissue .
X kg/ha 1
3. Index of Plant Concentration Increment Permitted by
Phytotoxicity (Index 6)
a. Formula
PP
Indejc 6 = —
where:
PP = Maximum plant tissue concentration
associated with phytotoxicity (ug/g DW)
BP = Background concentration in plant tissue
(Ug/g DW)
b. Sample calculation
1206 Ug/g DW
°*U ~ 200 Ug/g DW
Effect on Herbivorous Animals
1. Index of Animal Toxicity Resulting from Plant Consumption
(Index 7)
a. Formula
I5 x BP
Index 7 =
TA
A-3
-------
where:
15 = Index 5 = Index of plant concentration
increment caused by uptake (unitless)
BP = Background concentration in plant tissue
(Ug/g DW)
TA = Feed concentration toxic to herbivorous
animal (ug/g DW)
b. Sample calculation
n m^j-t - 1.003268 x 36.3 Ug/g DW
U.U/DJ// — . -,_ / .... —
477 ug/g DW
2. Index of Animal Toxicity Resulting from Sludge Ingestion
(Index 8)
a. Formula
_. A_ . _ BS x GS
If AR = 0, I8 = —^
if AR # o, i8 = SCT* GS
where:
AR = Sludge application rate (mt DW/ha)
SC = Sludge concentration of pollutant
(Ug/g DW)
BS = Background concentration of pollutant in
soil (ug/g DW)
GS = Fraction of animal diet assumed to be soil
(unitless)
TA = Feed concentration toxic to herbivorous
• animal (ug/g DW)
b. Sample calculation
If AR - 0, 0.714285 = 2°°°°J1a/* ""' °'05
' 1400 Ug/g DW
If AR # 0 10= 28000 Ug/g DW x 0.05
If AR f 0, 1.0 -
E. Effect on Humans
1. Index of Human Toxicity Resulting from Plant Consumption
(Index 9)
a. Formula
[(15 - 1) BP x DT] + DI
Index 9 =
ADI
A-4
-------
where:
15 = Index 5 = Index of plant concentration
increment caused by uptake (unitless)
BP = Background concentration in plant tissue
(Ug/g DW)
DT = Daily human dietary intake of affected
plant tissue (g/day DW)
DI = Average daily human dietary intake of
pollutant (ug/day)
ADI = Acceptable daily intake of pollutant
(Ug/day)
b. Sample calculation (toddler)
n /OQooc _ [(1.003268 - 1) x 9'4 Ug/g DW x 74.5 g/dayl + 15000 ue/dav
0.429225 - ug/day
2. Index of Human Toxicity Resulting from Consumption of
Animal Products Derived from Animals Feeding on Plants
(Index 10)
a. Formula
[(Is - 1) BP x UA x DA] + DI
index 10 = —5 - — -
where:
15 = Index 5 = Index of plant concentration
increment caused by uptake (unitless)
BP = Background concentration in plant tissue
(Ug/g DW)
UA = Uptake slope of pollutant in animal tissue
(Ug/g tissue DW [Ug/g feed DW]-1)
DA = Daily human dietary intake of affected
animal tissue (g/day DW)
v DI = Average daily human dietary intake of
pollutant (ug/day)
ADI = Acceptable daily intake of pollutant
(Ug/day)
b. Sample calculation (toddler)
0.428573 =
1.003268-1) x 36.3 Ug/g DW x 0.26 Ug/g tissue[ug/g feed]"1 x 0.97 g/dayl + 15000 He/day
35000 yg/day
A-5
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3. Index of Human Toxicity Resulting from Consumption of
Animal Products Derived from Animals Ingesting Soil
(Index 11)
a. Formula
_,. ._ n _ , .. (BS x GS x UA x DA) * PI
If AR = 0, Index 11 = TTTT
re AD J, n T A 11 (SC x GS x UA x DA) + PI
If AR f 0, Index 11 =
where:
AR = Sludge application rate (mt PW/ha)
BS = Background concentration of pollutant in
soil (ug/g PW)
SC = Sludge concentration of pollutant
(Ug/g PW)
GS = Fraction of animal diet assumed to be soil
(unitless)
UA = Uptake slope of pollutant in animal tissue
(Ug/g tissue PW [Ug/g feed PW"1]
PA = Average daily human dietary intake of
affected animal tissue (g/day PW)
PI = Average daily human dietary intake of
pollutant (ug/day)
API = Acceptable daily intake of pollutant
(Ug/day)
b. Sample calculation (toddler)
0.438659 =
(28000 yg/g DW x Q.Q5 x 0.26 Ug/g tissue [ug/g feed]"1 x 0.97 g/day PW) + 15000 Ug/day
35000 ug/day
4. Index of Human Toxicity Resulting from Soil Ingestion
(Index 12)
a. Formula
(II x BS x PS) + PI
Index 12 =
API
Pure sludge ingestion: Index 12 = rrr
where:
1^ = Index 1 = Index of soil concentration
increment (unitless)
SC = Sludge concentration of pollutant
(Ug/g PW)
A-6
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BS = Background concentration of pollutant in
soil (ug/g DW)
DS = Assumed amount of soil in human diet
(g/day)
DI = Average daily dietary intake of pollutant
(Ug/day)
ADI = Acceptable daily intake of pollutant
(Ug/day)
b. Sample calculation (toddler)
, OOQ<.,, (1.000997 x 20000 ug/g DW x 5 g soil/day) + 15000 ug/day
3'288564 35000 ug/day
Pure sludge:
_ (28000 Ug/g DW x 5 g soil/day) + 15000 Ug/day
— -irnnn I i
35000 Ug/day
5. Index of Aggregate Human Toxicity (Index 13)
a. Formula
Index 13 = I9 + I10 + ln + I12 -
where:
Ig = Index 9 = Index of human toxicity
resulting from plant consumption
(unitless)
IIQ = Index 10 = Index of human toxicity
resulting from consumption of animal
products derived from animals feeding on
plants (unitless)
III ~ Index 11 = Index of human toxicity
resulting from consumption of animal
products derived from animals ingesting
soil (unitless)
Il2 - Index 12 = Index of human toxicity
resulting from soil ingestion (unitless)
DI = Average daily dietary intake of
pollutant (ug/day)
ADI = Acceptable daily intake of pollutant
(Ug/day)
b. Sample calculation (toddler)
3.299307 = (0.429225 + 0.428573 + 0.438659 + 3.288564) -
A-7
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II. LANDFILLING
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
III. INCINERATION
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the right
to conduct such an assessment for this option in the future.
IV. OCEAN DISPOSAL
Based on the recommendations of the experts at the OWRS meetings
(April-May, 1984), an assessment of this reuse/disposal option is
not being conducted at this time. The U.S. EPA reserves the.right
to conduct 'such an assessment for this option in the future.
A-8
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