United States
Environmental Protection
Agency
Office of Water
Regulations and Standards
Washington nc 20460
Water
June, 1985
Environmental Profiles
and Hazard Indices
for Constituents
of Municipal Sludge:
Fluoride
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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 baVvs 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 Che
basis of information presented in this document.
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TABLE OP CONTENTS
Page
PREFACE i
1. INTRODUCTION 7.. 1-1
2. PRELIMINARY CONCLUSIONS FOR FLUORIDE IN MUNICIPAL SEWAGE
SLUDGE 2-1
Landspreading and Distribution-and-Marketing 2-1
Landfilling 2-2
Incineration 2-2
Ocean Disposal 2-2
3. PRELIMINARY HAZARD INDICES FOR FLUORIDE IN MUNICIPAL SEWAGE
SLUDGE 3-1
Landspreading and Distribution-and-Marketing 3-1
Effect on soil concentration of fluoride (Index 1) 3-1
Effect on soil biota and predators of soil biota
(Indices 2-3) 3-3
Effect on plants and plant tissue
concentration (Indices 4-6) ..'. '..' 3-4
Effect on herbivorous animals'(Indices 7-&) 3-9
Effect on humans (Indices 9-13) 3-12
Landf illing 3-21
Incineration 3-21
Ocean Disposal *. 3-21
4. PRELIMINARY DATA PROFILE FOR FLUORIDE IN MUNICIPAL SEWAGE
SLUDGE 4-1
Occurrence 4-1
Sludge 4-1
Soil - Unpolluted .'.. 4-1
Water - Unpolluted '. 4-2
Air 4-2
Food 4-3
Human Effects 4-4
Ingestion 4-4
Inhalation 4-5
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TABLE OF CONTENTS
(Continued)
Page
Plant Effects 4-5
Phytotoxicity 4-5
Uptake 4-6
Domestic Animal and Wildlife Effects 4-7
Toxicity 4-7
Uptake 4-7
Aquatic Life Effects 4-7
Soil Biota Effect 4-7
Physicochemical Data for Estimating Fate and Transport 4-7
5 . REFERENCES .' 5-1
APPENDIX. PRELIMINARY HAZARD INDEX CALCULATIONS FOR
FLUORIDE IN MUNICIPAL SEWAGE SLUDGE A-l
ill
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SECTION 1
INTRODUCTION
This preliminary data profile is one of a series of profiles deal-
ing with chemical pollutants potentially of concern in municipal sewage
sludges. Fluoride was initially identified as being of potential con-
cern when sludge is landspread (including distribution and marketing).41
This profile is a compilation of information that may be useful in
determining whether fluoride 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 repre-
sent 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", Sec-
tion 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 perti-
nent to landspreading and distribution and marketing practices are
included in this profile. The calculation formulae for these indices
are shown in 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 FLUORIDE 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 formu-
lae are shown in the Appendix.
I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING
A« Effect on Soil Concentration of Fluoride
Soil concentrations of fluoride are not expected to change
significantly due to landspreading of sludge. A high applica-
tion of sludge containing a typical concentration of fluoride
may increase the soil concentration due to dilution, and a
high application of sludge containing a high concentration of
fluoride may increase the soil concentration by 30 percent
(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
Fluoride in sludge-amended soil is not expected to pose a
hazard to plants (see Index 4). The concentrations of fluor-
ide in plants consumed by animals and humans are not expected
to increase as a result of landspreading sludge, except when
sludge with a high fluoride concentration is applied at high
rates (see Index 5). The maximum increase in fluoride
concentration predicted for plants in the human and animal
diet will not be precluded by phytotoxicity (see Index 6).
D. Effect on Herbivorous Animals
Landspreading of sludge is not expected to pose a toxic hazard
from fluoride to grazing animals that feed on plants grown on
sludge-amended soil (see Index 7)., or that incidentally ingest
sludge-amended soil (see Index 8).
B. Effect on Humans
Landspreading of sludge is not expected to pose a health
hazard from fluoride to humans who consume plants grown on
sludge-amended soil (see Index 9); ingest animal products
derived from animals fed crops grown on sludge-amended soil
(see Index 10); or consume animal products derived from
animals ingesting sludge-amended soil (see Index 11).
2-1
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Ingestion of sludge-amended soil is not expected to pose a
human health hazard due to fluoride, except possibly for
toddlers who ingest pure sludge containing a high
concentration of fluoride (see Index 12). An aggregate human
health hazard due to fluoride is not expected to occur as a
result of landspreading sludge (see Index 13).
II. LANDPILLING
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
(Aprilr-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 FLUORIDE
IN MUNICIPAL SEWAGE SLUDGE
I. \ LANDSPREADING AND DISTRIBUTTON-AND-MARKETING
A. Effect on Soil Concentration of Fluoride
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 ^50 -kg available
nitrogen per hectare.
SO 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. Assumptions/Limitations - Assumes pollutant is dis-
tributed and retained within the upper IS cm of soil
(i.e., the plow layer), which has an approximate
mass (dry matter) of 2 x 103 mt/ha.
c. Data Used and Rationale
i. Sludge concentration of pollutant (SC)
Typical 86.4 ug/g DW
Worst 738.7 Ug/g DW
The typical and worse sludge concentrations are
the median and 95th perentile values statis-
tically derived from sludge concentration data
3-1
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from a survey of 40 publicly-owned treatment
works (POTWs) (U.S. EPA, 1982). (See
Section 4, p. 4-1.)
ii. Background concentration o£ pollutant in soil
(BS) = 292 Ug/g DW
The background soil concentration for fluoride,
292 Ug/g, is the mean concentration for soils 0
to 12 inches in depth. (Robinson and Edgington,
1946, as cited in National Academy of Sciences
(NAS), 1971). The mean represents concentra-
tions from 30 samples throughout the U.S. rang-
ing from 20 ug/g to 1620 Ug/g. In the same
study, concentrations of fluoride in soil from
0 to 3 inches depth ranged from 20 to 500 Ug/g
with a mean of 190 Ug/g. Since fluoride con-
centration generally increases with depth, the
concentrations for 12 inches was selected con-
servatively as a representative concentration.
This selected value falls within the normal
fluoride concentration range of 200 to 300 Ug/g
for mineral soils (U.S. EPA, 1980). (See Sec-
tion 4, p. 4-1.)
d. Index 1 Values
Sludge Application Rate (mt/ha)
Sludge
Concentration 0 5 50 500
Typical
Worst
1
1
1.0
1.0
0.98
1.0
0.86
1.3
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 reduc-
tion by one-half.)
£. Preliminary Conclusion - Soil concentrations of
fluoride are not expected to change significantly
due to landspreading of sludge. A high application
of sludge containing a typical concentration of
fluoride may decrease the soil concentration due to
dilution, and a high application of sludge
containing a high concentration of fluoride may
increase the soil concentration by 30 percent.
3-2
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B. 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.
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) = 292 yg/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 so'il 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.
3-3
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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) = 292 Ug/g DW
See Section 3, p. 3-2.
iii. Uptake slope of pollutant in soil biota (UB) -
Data not immediately'available.
iv. Background concentration in soil biota (BB) -
Data not immediately available.
v. Peed concentration toxic to predator (TR) -
Data not immediately available.
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 concentra-
tion shown to be toxic for some plant.
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) = 292 yg/g DW
See Section 3, p. 3-2.
3-4
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ill. Soil concentration toxic to plants (TP) =
454 ug/g DW
The soil concentration toxic to plants was
chosen conservatively. This concentration
represents the highest concentration tested by
Davis (1980) in a study of rye grass uptake of
fluoride following application of fluoride-rich
sludge. No adverse effects were observed at
this concentration, and, in fact, the yield was
increased. Cooke et al. (1976, as cited by
Davis, 1980) found no symptoms of toxicity in
rye grass grown on fluorspar waste containing
17.422 fluoride. Although Cooke et al. (1976)
reported a higher soil concentration where no
effects were observed, the concentration of
454 Ug/g was chosen as a conservative estimate
(304 Ug/g plus 150 Ug/g background in experi-
mental soil) of a concentration where effects
might occur. A study by Morse (1935), cited in
Eagers (1969), reported that a concentration of
100 Ug/g greatly diminished seed germination of
maize and 400 Ug/g completely inhibited germi-
nation. However, these concentrations repre-
sent soluble fluoride rather than total
fluoride, which would normally be less avail-
able to plants. Another study- by Thompson et
al. (1979) reported fluoride damage to fir
trees where soil concentrations of fluoride
were 36 Ug/g. However, the soil fluoride con-
centrations in this study'were the result of
deposit of airborne fluoride from a factory.
It was not clear to what degree the damage
observed was due to atmospheric exposure to
fluoride, since plants are known to accumulate
fluoride and suffer injury from atmospheric
exposure to fluoride (U.S. EPA, 1980). (See
Section 4, p. 4-9.)
d. Index 4 Values
Sludge Application Rate (mt/ha)
Sludge
Concentration 0 5 50 500
Typical
Worst
0.64
0.64
0.64
0.65
0.63
0.67
0.55
0.84
e. Value Interpretation - Value equals factor by which
soil concentration exceeds phytotoxic concentration.
Value > 1 indicates a phytotoxic hazard may exist.
f. Preliminary Conclusion - Fluoride in sludge-amended
soil is not expected to pose a hazard to plants.
3-5
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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 Che
animal diet. See also Index 6 for consideration of
phytotoxicity.
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) = 292 ug/g DW
See Section 3, p. 3-2.
iii. Conversion factor between soil concentration
and application rate (CO) = 2 kg/ha
Assumes pollutant is distributed and retained
within upper IS 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:
Rye grass (tops)
0.0786 ug/g tissue DW (kg/ha) -1
Human diet:
Ground cover (cops)
0.0098 Wg/g tissue DW (kg/ha) ~1
Very limited data appropriate for calculation
of upcake slopes are immediately available.
Rye grass was chosen as the representative
plant consumed by animals. The uptake slope of
0.0786 was calculated from data presented by
Davis (1980) in a study which applied fluoride-
3-6
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rich sludge at rates whictK equated to 0 to 672
kg/ha. An uptake slope for. fescue was calcu-
lated to be 0.0059 Ug/g tissue DW (kg/ha)'1
based on data presented by Wright et al.
(1978). However, to be conservative, the
higher uptake slope for rye grass was chosen.
No data were immediately available to estimate
the uptake slope for plants consumed by humans.
An uptake slope of 0.0098 was available for
ground cover consisting largely of clover
(Trifoliam repens). Wright et al. (1978)
studied the uptake of fluoride in ground cover
grown in soils contaminated with flouride. The
value for ground cover appeared to be the most
representative uptake slope available. It is
assumed that uptake of fluoride by leafy vege-
tables is similar to the ground cover uptake.
(See Section 4, p. 4-10.)
v. Background concentration in plant tissue (BP)
Animal diet:
Rye grass (tops) 6.0 Ug/g DW
Human diet:
Ground cover (tops) 6.2 Ug/g DW
Background concentrations of fluoride in rye
grass and ground cover are those given by Davis
(1980) and Wright et al. (1978), respectively,
in the studies presenting data used to calcu-
late the uptake slopes. (See Section 4, p. 4-
10.)
d. Index S Values
Sludge Application
Rate (mt/ha)
Sludge
Diet Concentration 05 50 500
Animal
Typical
Worst
1.0
1.0
0.99
1.0
0.87
1.3
-0.077
3.3
Human Typical 1.0 1.0 0.98 0.87
Worst 1.0 1.0 1.0 1.3
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 - The concentrations of
fluoride in plants consumed by animals and humans
are not expected to increase as a result of
3-7
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Landspreading sludge, except when sludge with a high
fluoride concentration is applied at high rates.
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 pur-
pose is to determine whether the plant concentration
increments calculated in Index 5 for high applica-
tions 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 phyto-
toxicity.
c. Data Used and Rationale
i. Maximum plant tissue concentration associated
with phytotoxicity (PP)
Animal diet:
Rye grass 2745 Ug/g DW
Human diet:
Spinach 857 Ug/g DW
Available data indicate- that rye grass is'able
to tolerate relatively high* tissue concentra-
tions without exhibiting phytotoxicity. A con-
centration of 2745 Ug/g DW caused no signs of
phytotoxicity in rye grass grown on fluorspar
waste (Cooke et al., 1976 cited in Davis,
1980). In a pot study using fluoride-rich
sludge, rye grass yield increased at the high-
est soil fluoride concentration; tissue fluor-
ide was 60 Ug/g DW (Davis, 1980). In spite of
the fact that phytotoxicity was not observed,
the data from Cooke et al. (1976) were chosen
to conservatively maximize the value of
Index 6. Spinach was chosen as a representa-
tive leafy vegetable consumed by humans for
which tissue concentrations associated with
toxicity were available. The spinach tissue
concentrations associated with toxicity ranged
from 803 to 857 Ug/g DW (U.S. EPA, 1980).
Therefore, the value of 857 Ug/g DW represents
the highest concentration associated with
phytotoxicity. (See Section 4, p. 4-9.)
3-8
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ii. Background concentration in plant tissue (BP)
Animal diet:
Rye grass 127 ug/g DW
Human diet:
Spinach 28.3 Ug/g DW
The background tissue concentration for rye
grass was obtained from Cooke et al. (1976)
because the PP value for rye grass was taken
from this study. Background concentrations for
spinach were 35 Ug/g DW reported by Benedict et
al., 1964 (as cited in U.S. EPA, 1980) and 1.3
to 28.3 llg/g DW reported by Garber, 1967 (as
cited in U.S. EPA, 1980). The value of
28.3 ]ig/g was chosen since it is between the
highest and lowest values reported. (See Sec-
tion 4, p. 4-6.)
d. Index 6 Values
Plant Index Value
Rye grass 22
Spinach 30
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 simi-
lar plant tissues given by Index 5. The lowest of
the two indices indicates the maximal increase which
can occur at any given application rate.
f. Preliminary Conclusion - The maximum increase in
fluoride concentration predicted for plants in the
human and animal diet will not be precluded by
phytotoxicity.
D. 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
3-9
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used co 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 S values used are those for an animal
diet (see Section 3, p. 3-7).
ii. Background concentration in plant tissue (BP) =
6 Ug/g DW
The background concentration value used is for
the plant chosen for the animal diet (see Sec-
tion 3, p. 3-7).
iii. Peed concentration toxic to herbivorous animal
(TA) = 40 Ug/g DW
The value for feed concentration represents the
maximum dietary tolerance for dairy cattle and
young cattle recommended by NAS (1980). The
maximum dietary tolerance for mature beef cat-
tle is 50 Ug/g (NAS, 1980). Minor morpholog-
ical lesions occur in the teeth' of cattle when
dietary fluoride exceeds 20 Ug/g during tooth
development; however, no relationship between
these lesions and animal performance has been
determined (NAS, 1980). Although Davis (1980)
reported a toxic fluoride threshold of 30 Ug/g
for cattle, Baxter et al. (1983) reported no
adverse effects for cattle at this feed
concentration. (See Section 4, p. 4-11.)
d. Index 7 Values
Sludge Application Rate (nut/ha)
Sludge
Concentration 0 5 SO 500
Typical
Worst
0.15
0.15
0.15
0.15
0.13
0.19
-0.012
0.50
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 - Landspreading of sludge is
not expected to pose a toxic hazard from fluoride to
herbivorous animals that feed on plants grown on
sludge-amended soil.
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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.
b. 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.
c. Data Used and Rationale
i. Sludge concentration of pollutant (SC)
Typical 86.4 (ig/g DW
Worst 738.7 ug/g DW
See Section 3, p. 3-1.
ii. Background concentration of pollutant in soil
(BS) = 292 yg/g DW
See Section 3, p. 3-2.
iii. Fraction of animal diet assumed to be soil (GS)
= 5Z
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, respec-
tively (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
3-11
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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
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) = 40 ug/g DW
See Section 3, p. 3-10.
d. Index 8 Values
Sludge Application Rate (me/ha)
Sludge
Concentration 0 5 50 500
Typical
Worst
0.37
0.37
0.11
0.92
0.11
0.92
0.11
0.92
e. 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.
f. Preliminary Conclusion - Landspreading of sludge is
not expected to pose a toxic hazard from fluoride to
grazing animals incidentally ingesting sludge-
amended soil.
B. 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
3-12
-------
considered 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.
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. 3-7).
ii. Background concentration in plant tissue (BP) =
28.3 Mg/g OW
The background concentration value used is for
spinach, which was chosen as the plant for the
human diet in Index 6 (see Section 3, p. 3-9).
This value was chosen, rather than the
background concentration for ground cover/
since it is higher, and thus, a more conserva-
tive choice and since it represents a plant
actually consumed by humans.
iii. Daily human dietary intake of affected plant
tissue (DT)
Toddler 7-4.5 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 com-
position 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.
iv. Average daily human dietary intake of pollutant
(DI)
Toddler 825 yg/day
Adult 2500 Ug/day
The estimated daily intake of fluoride for tod-
dlers, age 1 to 3, was reported to range from
417 to 825 pg/day when intake from food and
3-13
-------
water are totalled (U.S. EPA 1980, adapted from
Maier, 1971). The higher value, 825 ug/day was
selected to represent the average daily intake.
U.S. EPA (1980) also reported that daily fluor-
ide intake from food for 1- to 2-year old
children was 250 to 550 ug/day (adapted from
Jones, Harries, and Martin, 1971); however,
this value did not include intake from drinking
water. The dietary intake in the U.S. for
adults from food and fluoridated drinking water
is 2500 tig/day (U.S. EPA, 1980 adapted from
Jones, Harries, and Martin, 1971). This value
is considered a conservative choice since
fluoridated drinking water is included in the
value. Other values reported are 1800 ug/day
for men and 1300 Ug/day for housewives (Cholak,
1960, in U.S. EPA, 1980), and 2100 to
2400 ug/day for young adult U.S. males (San
Filippo and Battistone, 1971, in U.S. EPA,
1980).
v. Acceptable daily intake of pollutant (ADI) =
4000 Ug/day
Singh and Jolly (1970, in U.S. EPA, 1980) con-
sidered that 4000 to 5000 ug is the daily limit
that may be ingested without hazardous body
storage. Areas of endemic fluorosis commonly
have levels of ingestion of over 8000 ug/day.
Since, no ADIs for- fluoride have been recom-
mended, the value of 4000 was chosen to
represent the ADI.
Index 9 Values
Group
Sludge
Concentration
Sludge Application
Rate (mt/ha)
5 50 500
Toddler
Typical
Worst
0.21
0.21
0.21
0.21
0.20
0.22
0.14
0.36
Adult
Typical
Worst
0.62
0.62
0.62
0.63
0.60
0.67
0.44
1.0
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.
3-14
-------
f. Preliminary Conclusion - Landspreading of sludge is
not expected to pose a health hazard from fluoride
to humans who consume crops grown on sludge-amended
soil.
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 prod-
ucts derived from domestic animals given feed grown
on sludge-amended soil (crop or pasture land) but
not directly contaminated by adhering sludge. Com-
pares 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.
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. 3-7).
ii. Background concentration in plant tissue (BP) =
6 ug/g DW
The background concentration value used is for
the plant chosen for the animal diet (see Sec-
tion 3, p. 3-7).
iii. Uptake slope of pollutant in animal tissue (UA)
= 0.03176 Ug/g tissue DW (ug/g feed DW)'1
The uptake slope for animal tissue was calcu-
lated from data for beef liver presented by
Suttie et al. (1958, in U.S. EPA, 1980). Beef
liver was chosen as the representative tissue
of grazing animals that is consumed by humans
and for which an uptake slope could be calcu-
lated. Uptake slopes were available for beef
heart and kidney (0.04365 and 0.31838, respec-
tively); however, these tissues generally do
not constitute a substantial fraction of the
3-15
-------
human diet. Uptake slopes were also calculated
for various turkey tissues, based on data pre-
sented by Anderson et al. (1955, in U.S. EPA,
1980). With the exception of bone, the uptake
slopes were lower than those for beef liver.
Also, turkeys are less representative of graz-
ing animals than cattle.
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. Conver-
sion to dry weight is based on data from U.S.
Department-of Agriculture (1975).
v. Average daily human dietary intake of pollutant
(DI)
Toddler 825 Ug/day
Adult 2500 Ug/day
See Section 3, p. 3-13.
vi. Acceptable daily intake of pollutant (ADI) =
4000 Ug/day
See Section 3, p. 3-14.
d. Index 10 Values
Sludge Application
Rate (me/ha)
Sludge
Group Concentration 0 5 50 500
Toddler
Typical
Worst
0.21
0.21
0.21
0.21
0.21
0.21
0.21
0.21
Adult Typical 0.62 0.62 0.62 0.62
Worst 0.62 0.62 0.62 0.62
e. Value Interpretation - Same as for Index 9.
f. Preliminary Conclusion - Landspreading of sludge is
not expected to pose a health hazard from fluoride
to humans who consume animal products derived from
livestock fed crops grown on sludge-amended soil.
3-16
-------
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 ail 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.
c. Data Used and Rationale
i. Animal tissue = Beef liver
See Section 3, p. 3-15.
ii. Background concentration of pollutant in soil
(BS) = 292 ug/g .DW
See Section 3, p. 3-2.
iii. Sludge concentration of pollutant (SC)
Typical 86.4 Ug/g DW
Worst 738.7 Ug/g DW
See Section 3, p. 3-1.
iv. Fraction of animal diet assumed to be soil (GS)
= 52
See Section 3, p. 3-11.
.v. Uptake slope of pollutant in animal tissue (UA)
• 0.03176 yg/g tissue DW (ug/g feed DW)"1
See Section 3, p. 3-15.
3-17
-------
vi. Daily human dietary intake of affected animal
tissue (DA)
Toddler 0.97 g/day
Adult S.76 g/day
See Section 3, p. 3-16.
vii. Average daily human dietary intake of pollutant
(DI)
Toddler 825 Ug/day
Adult 2SOO Ug/day
See Section 3, p. 3-13.
viii. Acceptable daily intake of pollutant (ADI) =
4000 ug/day
See Section 3, p. 3-14.
d. Index 11 Values
Sludge Application
Rate (mt/ha)
Sludge
Group Concentration 0 5 SO 500
Toddler
Adult
Typical
Worst
Typical
Worst
0.21
. 0.21
0.63
0.63
0.21
0.21
0.63
0.63
0.21
0.21
0.63
0.63
0.21
0.21
0.63
0.63
e. Value Interpretation - Same as for Index 9.
f. Preliminary Conclusion - Landspreading of sludge is
not expected to pose a health hazard from fluoride
to humans who consume animal products derived from
livestock which had incidentally ingested sludge-
amended soil.
4. 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 for 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
3-18
-------
deriving the ADI provide protection for the child,
taking into account the smaller body size and any
other differences in sensitivity.
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 86.4 pg/g DW
Worst 738.7 yg/g DW
See Section 3, p. 3-1.
iii. Background concentration of pollutant in soil
(BS) = 292 yg/g DW
See Section 3, p. 3-2.
iv. Assumed amount of soil in human diet (DS)
Pica child 5 g/day
Adult 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 825 Ug/day
Adult 2500 Ug/day
See Section 3, p. 3-13.
vi. Acceptable daily intake of pollutant (ADI) =
4000 ug/day
See Section 3, p. 3-14.
3-19
-------
Index 12 Values
Sludge Application
Rate (at/ha)
Group
Toddler
Adult
Sludge
Concentration
Typical
Worst
Typical
Worst
0
0.57
0.57
0.63
0.63
5
0.57
0.57
0.63
0.63
50
0.56
0.58
0.63
0.63
500
0.52
0.68
0.63
0.63
Pure
Sludge
0.31
1.1
0.63
0.63
e. Value Interpretation - Same as for Index 9.
£» Preliminary Conclusion - Ingestion of sludge-amended
soil is not expected to pose a human health hazard
due to fluoride, except possibly for toddlers who
ingest pure sludge containing a high concentration
of fluoride.
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.
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)
Group
Toddler
Adult
Sludge
Concentration
Typical
Worst
Typical
Worst
0
0.57
0.57
0.63
0.63
5
0.57
0.57
0.62
0.63
50
0.56
0.60
0.60
0.68
500
0.45
0.83
0.44
1.0
e. Value Interpretation - Same as for Index 9.
f. Preliminary Conclusion - An aggregate human health
hazard due to fluoride is not expected to occur as a
result of landspreading sludge.
3-20
-------
II. LANDPILLING
Based on the recommendations of the experts at the OWRS meetings
(April-May, 198'4-^an assessment of this reuse/disposal option is
not being conducteoNat 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.
3-21
-------
SECTION 4
PRELIMINARY DATA PROFILE FOR FLUORIDE IN MUNICIPAL SEWAGE SLUDGE
I. OCCURRENCE
A. Sludge
B.
Frequency of Detection
Assumed 1002 because of its use as an
additive in water, toothpaste, etc.,
and because of its ubiquitous nature.
Concentration
Sludges of 16 U.S. cities
Median
Mean
95th percentile
Minimum
86.4 yg/g DW
167.3 yg/g DW
738.7 yg/g DW
2.2 Ug/g DW
33,500 ppm in fluoride-contaminated
sludge
Soil - Unpolluted
1. Frequency of Detection
13th element in abundance constituting
0.06 to 0.09Z of earth's crust
2. Concentration
209+23 ppm (DW) in controlled soil
(Great Britain)
20 to 500 ppm in soils 0 to 3 in.
in depth, mean 190 ppm
Furr et al.,
1976 (p. 684)
Derived from
sludge concen-
tration data
presented in
U.S. EPA, 1982
Davis, 1980
(p. 279)
U.S. EPA, 1980
(p. 1)
Wright et al.,
1978 (p. 305)
Robinson and
Edgington,
1946 in MAS,
1971 (p. 6)
4-1
-------
20 Co 1620 ppm in soils 0 to 12 in. in
depth, mean 292 ppm (30 soils sampled
throughout the United States)
Max levels: Idaho Soil - 3870 ppm
Tenn. Soil - 8300 ppm
200 to 300 ppm "normal" for mineral
soils
200 ppm common value
Water - Unpolluted
1. Frequency of Detection
Assumed 100Z
2. Concentration
a. Freshwater
<0.3 ppm
b. Seawater
1.4 to l.S ppm
1.3 mg/L
c. Drinking water
0.02 to 0.1 ppm in northwest United
States; >0.2 ppm in west, midwest
and south U.S. water supplies
Air
1. Frequency of Detection
Only 3Z of samples from rural locations
had detectable fluoride
Robinson and
Edgington,
1946 in NAS,
1971 (p. 6)
Robinson and
Edgington,
1946 in NAS
1971 (p. 6)
MeIntire, 1949
in NAS, 1971
(p. 6)
U.S. EPA, 1980
(p. 2)
Bowen, 1966 in
Davis, 1980
U.S. EPA, 1980
(p. 9)
U.S. EPA, 1980
(p. 9)
Hem, 1970
(p. 11)
NAS, 1971
(p. 6)
NAS, 1971
(p. 233)
4-2
-------
2. Concentration
a. Urban
<0.05
>3 Ug/m in industrial areas
87Z of samples <0.05 Ug/m3
b. Rural
-------
2. Concentration
Typical Concentrations in Fresh Food Cholak, 1959,
in NAS, 1971
Meats 0.01 - 7.70 ppm (p. 8)
Fish <0.10 - 24.00 ppm
Citrus fruits 0.04 - 0.36 ppm
Noncitrus fruits 0.02 - 1.32 ppm
Vegetables 0.10 - 3.00 ppm
Cereals and
cereal products <0.10 - 20.00 ppm
Milk 0.04 - 0.5S ppm
Eggs 0.00 - 2.05 ppm
Butter 0.40 - 1.50 ppm
Cheese 0.13 - 1.62 ppm
Sugar 0.10 - 0.32 ppm
Coffee 0.20 - 1.60 ppm
Beer 0.15 - 0.86 ppm
Wine 0.00 - 6.34 ppm
II. HUMAN EFFECTS
A. Ingestion
1. Carcinogenic!ty
a. Qualitative Assessment
No evidence of carcinogenicity U.S. EPA, 1980
induced by ingestion of fluorides (p. 320)
2. Chronic Tozicity
a. ADI
4000 to 5000 Mg/day - daily limit Singh and
that may be ingested without Jolly, 1970 in
hazardous body storage U.S. EPA, 1980
(p. 292)
b. Effects
No effects observed at drinking California
water levels of 0.8 mg/L State Water
Teeth mottled in children at Resources
drinking water levels of Control Board,
1.0 to 6.0 mg/L 1978 (p. 190)
Sublethal level in drinking water
• at 115 mg/L
Toxic to man in drinking water
at 180 mg/L
Lethal dose in drinking water
of 2000 mg/L
4-4
-------
3. Absorption Factor
1 to 10 percent
4. Existing Regulations
Ambient Water Quality Criteria
^1.0 mg/L
B. Inhalation
1. Careinogenicity
a. Qualitative Assessment
Not found to be carcinogenic to
humans when inhaled.
2. Chronic Toxicity
a. Inhalation Threshold or MPIH
See below, "Existing Regulations"
b. Effects
Overexposure (sh.ort term):
Irritation of eyes and respiratory
tract.
Overexposure (long-term): Calcifi-
cation of bones and ligaments, mot-
tled teeth, or skin rash.
3. Absorption Factor.
Data not immediately available.
4. Existing Regulations
2.5 mg/m3 (TWA)
III. PLANT EFFECTS
A. Phytotoxicity
Most plants absorb very little fluoride
from the soil
See Table 4-1.
California
State Water
Resources
Control Board,
1978 (p. 190)
U.S.. Dept. of
Labor, 1978
ACGIH, 1982
NAS, 1971
(p. 7)
4-5
-------
No cases of fluorosis have ever been
ascribed to excessive "natural" accumula-
tion of fluorides in plant tissues
Threshold for injury for susceptible plants
is <150 ppm in tissues
Intermediate plants threshold is >200 ppm
B. Uptake
"Normal" concentrations: Festuca rubra
5.01+1.1 ppm DW
Composite ground cover 8.1+1.3 ppm DW
"Natural" forage fluoride 5-10 ppm DW
Uncontaminated alfalfa (107 samples)
0.8-36.5 ppm (DW), 3.6, median 2 ppm
Crops uncontaminated by aerial deposition
of fluorides contain 2 to 20 ppm fluoride
2 to 20 Ug/g (DW)
Fluoride Concentration in Selected Plants
Plant
Alfalfa
Grass, Hay
Corn
Wheat
Rye
Oats
Rice
Potato
Lettuce
Spinach
Spinach
Celery
Carrot
Tomato
Part
Tops
Plant
Cob
Grain
Grain
Grain
Grain
Tuber
Leaf
Leaf
Leaf
Stalk
Root
Fruit
Fluoride
(ppm DW)
7-15
1-6
1.6
1
1.5
0.5
0.76
1.5-3.0
4.4-11.3
1.3-28.3
35
2
0.4-8.4
2
Baxter et al.,
1983
NAS, 1971
(p. 98)
Wright et al.f
1978 (p. 305)
NAS, 1971
(p. 136)
Baxter et al.,
1983 (p. 14)
U.S. EPA, 1980
(p. 5)
U.S. EPA, 1980
(p. 119-120)
Zimmerman and
Hitchcock, 1956
Garber, 1967
Garber, 1967
Garber, 1967
Garber, 1967
Garber, 1967
Garber, 1967
Garber, 1967
Garber, 1967
Garber, 1967
Benedict et al,
1964
Zimmerman and
Hitchcock, 1956
Garber, 1967
Zimmerman and
Hitchcock, 1956
4-6
-------
<30 ppm in 902 of 168 samples of Suttie et al.,
dairy feed, "some samples had over 1958 in U.S.
200 ppm" EPA, 1980
(p. 137)
"There is little or no relation between NAS, 1971
total fluoride content of soil and the (p. 136)
fluoride content of plants grown on it.
There is some indication that acid soil
promotes fluoride uptake..."
"Because soil fluoride may be unavailable U.S. EPA, 1980
to plants, a direct relationship between
soil fluoride content and plant fluoride
content does not necessarily exist."
See Table 4-2.
IV. DOMESTIC ANIMAL AND WILDLIFE EFFECTS
A. Toxicity
See Table 4-3.
B. Uptake
See Table 4-4.
V. AQUATIC LIFE EFFECTS
Data not immediately available.
VI. SOIL BIOTA EFFECTS
Only data available are fluoride pesticides
VII. PHYSICOCHEMICAL DATA FOE ESTIMATING FATE AND TRANSPORT
Low soil pH greatly increases fluoride Doss et al.,
solubility and, therefore, availability 1977 (p. 367)
of fluoride to plants
Fluorides are mostly insoluble and, therefore, Baxter, et al.,
not particularly available to plants 1983 (p. 14)
CaF2 (fluorite) Hodgman et al.,
Molecular wt.: 78.08 1961
Solubility in water (18°C): 0.0016 g/100 mL
MgF2 (sellaite) Hodgman et al.,
Molecular wt.: 62.32 1961
Solubility in water (18°C): 0.0076 g/100 mL
4-7
-------
NaF (villiaumite) Hodgman et al,
Molecular wt.: 42.00 1961
Solubility in water (18°C): 4.22 g/100 raL
4-8
-------
TABLE 4-1. PHYTOTOXICITY OP PLUORIDB
Plant/Tissue
Rye grass
Perennial rye grass
(Loliuo perenne)
Haize
Pir Tree
Apple/Leaf
Apricot/leaf
Bean/leaf
Carrot/leaf
Corn/leaf
Spinach/leaf
Tomato/leaf
Citrus/leaves
Control
Chemical Tissue
Porn Growth Concentration
Applied Medium (|ig/B DW)
P-rich liquid-
digested sludge
(pot study)
Fluorspar
waste
Soluble P
Airborne P
HP gas
HP gas or
industrial
emission
NaP
HP gas
HP gas
NaP
NaP
NR
soil pH 7.0 6
NB 174
NRa NR
NR 7
NAC NA
NA NA
NR NR
NR NR
NR NR
NR
NR NR
NR NR
experimental'
Soil
Concentration
(MK/g W)
188
246
302
454
200
100
400
10
16
36
205
90S
NA
NA
NR
NA
• NA
NR
NR
NR
experimental
Application
Rate
(kg/ha)
84
168
336
672
NR
NA
NA
NR
NA
NA
NR
NR
NR
Experimental
Tissue
Concentration
(Ug/g DU)
HR
NR
NR
60
274S
NR
NR
7
44
91
141
281
72-234
S8-640
O10
2SO-723
48-491
803-8S7
277-2179
100-200
Effect
Increased yield
Increased yield
Increased yield
Increased yield
Mo symptoms of
toxicity
Greatly diminishes
germination
Completely inhibits
germination
No damage
Slight damage0
20-30Z trees deadb
40-60Z trees deadb
80-95Z trees deadb
Toxic symptoms
Toxic symptoms
Toxic symptoms
Toxic symptoms
Toxic symptoms
Toxic symptoms
Toxic symptoms
Significant yield
References
Davis. 1980
Cooke et al., 1976
in Davis 1980
(p. 181)
Horse, 1935 in
Eagers. 1969
Horse. 1935 in
Eagers, 1969
Thompson et al.,
1979
U.S. EPA, 1980
HAS, 1971
and growth reduction
a NR - Not reported.
D Results of study unclear as to whether toxicity was due to atmospheric- P damage or soil concentration.
c NA = Not available.
-------
TABLE 4-2. UPTAKB OP FLUORIDB BY PLANTS
Plant/Tissue
Bye grass/
tops
Ground covered/
tops'
Fescue/tops
•M - number of
Application
Medium
(Study Type)
F-rich liquid-digested
sludge (pot study)
contaminated soil
contaminated
soil
application rates, including control.
Bange (N)« of
Control Tissue
Application Bates Concentration
Soil pU ( kg/ha )•
7.0
NB
NB
bSlope - y/x: x • kg applied/ha; y = Mg/g plant tissue dry
concentrations reported in Wright (1978) converted by kg/ha
^High frequency
of Tri folium repens (clover).
0-672 (5)
0-348,000 (4)c
0-348,000 (4)c
weight.
by subtracting background
(Vig/g DW)
6
6.2
4.7
.
concentration and then
Uptake
Blopeb
0.0786
0.0098
0.0059
calculating mass
Beferences
Davis, 1980
Wright et al..
1978
Wright et al.,
1978
F in ha IS en deep.
-------
TABLE 4-3. TOXICITY OP PLUOBIBB TO DOMESTIC ANIMALS AND WILDLIFE
Species
Sheep
Horaea
Cattle
Cattle
Cattle, horses,
sheep
Cattle, auine, sheep,
horse
Nature dairy cattle
and young cattle
Mature beef
Young cattle
Feeder lambs
Horses
Pigs
Chickens
Chemical
Pom
Ped
NB
NB
NR
NB
Sludge
NB
NaP
NaP
NaP
NaF
NaP
NaP
NaP
Peed
Concentration
(Ug/g)
60
30
30
30
<100
300
40
SO
20
ISO
40
ISO
200
Water
Concentration
(mg/L)
NB
NB
NR
NB
NB
NR
NB
NR
NB
NB
NB
NB
NR
Pally
Intake
,
NB
NB
NR
NB
NR
NR
NR
NR
NR
NR
NR
NR
NR
Duration
of Study
NB
NB
NB
NB
NB
NR
NB
NB
NR
NB
NB
NB
NB
Effects Beferences
Safe level U.S. EPA, 1980
Safe level
Toxic- threshold Davis, 19BO
No adverse effects Baxter et al., 1983
Preaents little hazard
to gracing animals
No acute signs of toxicosis U.S. EPA, 1980
observed
Maximum dietary tolerance NAS, 1980
Maximum dietary tolerance
Minor morphological lesions NAS, 1980
in teeth | however no
relationship between teeth
and animal performance
established
Maximum dietary tolerance
Maximum dietary tolerance
Maximum dietary tolerance
Maximum dietary tolerance
-------
TABLE 4-3. (Continued)
-C-
G
Speciea
Turkeys
Cattle
Sheep
Sheep
Chemical
Fora
Fed
NR
NR
NaP
CaF2
Peed
Concentration
(M8/8>
ISO
>600
40
2400
Water
Concentration
(«g/L)
NR
NR
NR
NR
Daily
Intake
(mg/kg)
NR
NR
NR
NR
Duration
of Study
MB
NR
2 daya
NR
Effects
Maximum dietary tolerance
Highly toxic
Inappetence
No inappetence
References
Hobbs et al.,
HAS, 1971
Ammerman et al
Anmerman et al
19S4 in
.. 1980
. , 1980
• MR = Not reported.
-------
TABLE 4-4. UPTAKE OP PLUOBIDB BY DOMESTIC AMIHALS AND WILDLIFE
Chemical
Species (N)a Porm Ped
Pield mole (5) CaP2
Voles CaP2
Apodemua (14)
Sore* (3)
Turkey NaP
Cattle NBe
Bange (Number)*
of Peed
Concentrations0
(pg/g DU)
6.6-4215(3)
6.6-4215(3)
0-1600(7)
0-50(5)
Tissue
Analysed
femur
kidney
liver
muscle
femur
femur
breast flesh
thigh flesh
liver
kidney
heart
liver
kidney
Control Tissue
Concentration
(pg/g DW)C
117
6.7
S.4
4.2
189
NSd
1.2
1.5
1.9
2.6
2-?
2.3
3.5
Uptake
SlopeD»c Beferences
0.4771 Wright et •!., 1978
0.0163
0.00596
0.00041
0.9238 Wright et •!., 1978
7.7648 Anderson et at., 1955 in
0.0173 U.S. EPA, 1980
0.0065
o.ooas
0.0203
0.0436S Suttie et al., 1958 in
0.03176 U.S. EPA, 1980 '
0.31838
•N ° Number of animals/treatment group.
bWhen tissue values were reported as wet weight, unless otherwise indicated a moisture content of 77Z was assumed for
kidney, 70Z for liver and 12Z for muscle.
cSlope ° y/xt y • MB/8 feed! * = P8/S tissue.
^NS = Tissue concentration not significantly increased.
eNR = Not reported.
-------
SECTION 5
REFERENCES
American Conference of Governmental Industrial Hygienists. 1982.
Threshold\Limit Values for Chemical Substances in Work Air Adopted
by ACGIH for 1982. Cincinnati, OH.
Ammerman, C. B., P. R. Henry, J. H. Conrad, K. R. Pick, and E. C.
Araujo. 1980. Inappetence in Ruminants as a Measure of Fluoride
Solubility in Various Phosphates. J. Dairy Sci. 63:1167-1171.
Anderson, J. 0., J. S. Hurst, D. C. Strong, H. Nielsen, D., A. Greenwood,
W. Robinson, J. L. Shupe, W. Binns, R. A. Bagley, and C. I. Draper.
1955. Effect of Feeding Various Levels of Sodium Fluoride to
Crowing Turkeys. Poult. Sci. 34:1147-1153. (As cited in U.S. EPA,
1980.)
Baxter, J. C., D. Johnson, E. Kienholz, W. D. Surge, and W. N. Cramer.
1983. EPA 600/2-83-012. Effects on Cattle from Exposure to Sewage
Sludge. Cincinnati, OH.
Benedict, H. M., J. M. Ross, and R. W. Wade. 1964. The Disposition of
Atmospheric Fluorides by Vegetation. Int. J. Hater Pollut. 3:279-
289. (As cited in U.S. EPA, 1980.)
Bertrand, J- E., H. 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.
Boswell, F. C. 1975. Municipal Sewage Sludge and Selected Element
Applications to Soil: Effect on Soil and Fescue. J. Environ.
Qual. 4(2):267-273.
Bowen, H. J. M. 1966. Trace Elements in Biochemistry. London Academic
Press. .(As cited in Davis, 1980.)
California State Water Resources Control Board. 1978. Water Quality
Criteria. Pasadena, CA.
Chaney, R. A., and C. A. Lloyd. 1979. Adherence of Spray-Applied
Liquid Digested Sewage Sludge to Tall Fescue. J. Environ. Qual.
8(3):407-411.
Cholak, J. 1959. Flourides: A Critical Review. I. The Occurrence of
Fluoride in Air, Food, and Water. J. Occup. Med. 1:501-511.
Cholak, J. 1960. Current Information on Quantities of Fluorides Found
in Air, Food, and Water. Arch. Ind. Health 21:312-315. (As cited
in U.S. EPA, 1980).
5-1
-------
Cooke, J. A., H. S. Johnson, A. W. Davison, and A. D. Bradshaw. 1976.
Fluoride in Planes Colonizing Fluorspar Mine Waste in Peak District
and Weardale. Environ. Pollut. 11:9-13. (As cited in Davis,
1980.)
Davis, R. D. 1980. Uptake of Fluorides by Ryegrass Grown in Soil
Treated with Sewage Sludge. Environ. Pollut. (Series B) 1:277-282.
Doss, G. J., L. E. St. John, Jr., and D. L. Lisk.^ 19.77. Studies of
Flouride Absorption by Plants Grown in Perlite. ^"Byll. Environ.
Contain. Toxicol. 18(3):366-369.
Eagers, R. Y. 1969. Toxic Properties of Inorganic Fluorine Compounds.
Elsevier Publishing Co. Ltd., NY.
Furr, A. K., A. W. Lawrence, S. S. Tong, M. C. Grandolfo, R. A.
Hofstader, C. A. Bache, W. H. Gutenmann, and D. J. Lisk. 1976.'
Multielement and Chlorinated Hydrocarbon Analysis of Municipal
Sewage Sludges of American Cities. Env. Sci. & Technol. 10(7)683-
687.
Garber, K. 1967. About the Fluorine Content of Plants. Qual. Plant
Mater. Veg. 15(l):29-36. (As cited in U.S. EPA, 1980.)
Hem, J. D. 1970. Study of Interpretation of the Chemical
Characteristics of Natural Water. Geological Survey Paper 1473,
Washington, D.C.
Hobbs, C. S., et al. 1954. Fluorosis in Cattle and Sheep. Tern. Agri.
Ezp.- Station Bull. 235. (As cited in NAS, 1971.)
Uodgman, C. D., R. C. Weast, and S. M. Selby (eds.). 1961. Handbook of
Chemistry and Physics, 42nd Edition. Chemical Rubber Publishing
Co., Cleveland, OH.
Jones, C. M., J. M. Harries, and A. E. Martin. 1971. Fluoride in Leafy
Vegetables. J. Sci. Food Agric. 22:602-605.
Mclntire, W. H. et al. 1949. Effects of Fluorine in Tennessee Soils
and Crops. Ind. Eng. Chem. 41:2466-2475. (As cited in NAS, 1971.)
Maier, F. J. 1971. Fluoridation. Crit. Rev. Environ. Control
2(3):387-430.
National Academy of Sciences. 1971. Fluorides. NAS, National Research
Council Committee on Biologic Effects of Atmospheric Pollutants,
Washington, D.C.
National Academy of Sciences. 1980. Mineral Tolerances of Domestic
Animals. NAS, National Review Council Subcommittee on Mineral
Toxicities in Animals, Washington, D.C.
Pennington, J. A. T. 1983. Revision of the Total Diet Study Food Lists
and Diets. J. Am. Diet. Assoc. 82:166-173.
5-2
-------
Robinson, W. 0., and 6. Edgington. 1946. Fluoride in Soils. Soil Sci.
61:341-353. (As cited in NAS, 1971.)
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.
San Filippo, F., and G. Battistone. 1971. The Fluorine Content of a
Representative Diet of the Young Adult Male. Clin. Chem. Acta
31:453-457. (As cited in U.S. EPA, 1980.)
Singh, A., and S. S. Jolly. 1970. Toxic Effects of Larger Doses of
Fluoride: III. Chronic Toxic Effects on the Skeletal System. In!
Fluorides and Human Health. World Health Organization, Geneva.
pp. 238-249. (As cited in U.S. EPA, 1980.)
Suttie, J. W., P. H. Phillips, and R. F. Miller. 1958. Studies of the
Effects of Dietary Sodium Fluoride on Dairy Cows. III. Skeletal
and Soft Tissue Fluorine Deposition and Fluorine Toxicosis. J.
Nutr. 65:293-304. (As cited in U.S. EPA, 1980.)
Thompson, L. K., S. S. Sidhu, and B. A. Roberts. 1979. Fluoride
Accumulations in Soil and Vegetation in the Vicinity of a
Phosphorus Plant. Environ. Pollut. 18:221-234.
Thornton, I., and P. Abrams. 1983. Soil Ingestion - A Major Pathway of
Heavy Metals into Livestock Grazing Contaminated Land. Sci. Total
Environ. 28:287-294.
'U.S. Department of Agriculture. 1975. Composition of Fpods. Agricul--
tural Handbook No. 8. •
U.S. Department of Labor. 1978. Occupational Health Guidelines for
Fluordie Dust (as Fluoride). Washington, D.C.
U.S. Environmental Protection Agency. 1980. Review of Environmental
Effects of Pollutants: IX. Fluoride. EPA-600/1-78-040.
Cincinnati, OH.
U.S. Environmental Protection Agency. 1982. Fate of Priority
Pollutants in Publicly-Owned Treatment Works. Final Report
Volume I. EPA-440/r82-303. Effluent Guidelines Division,
Washington, D.C. September.
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.
5-3
-------
Wright, D. A., A. W. Davison, and H. S. Johnson. 1978. Fluoride
Accumulation by Long-Tailed Field Mice (Apodemus sylvantuns L.) and
Field Voles (Microtus agrestis L.) from Polluted Environments.
Environ. Pollut. 17:303-310.
Zimmerman, P. W., and A. E. Hitchcock. 1956. Susceptibility of Plants
to Hydrofluoric Acid and Sulfur Dioxide Gases. Contrib. Boyce
Thompson Inst. 18:263-279.
5-4
-------
APPENDIX
PRELIMINARY HAZARD INDEX CALCULATIONS FOR FLUORIDE
IN MUNICIPAL SEWAGE SLUDGE
I. LANDSPREADING AND DISTRIBUTE ON- AND-MARKETING
A. Effect on Soil Concentration of Fluoride
1. Index of Soil Concentration Increment (Index 1)
a. Formula
... . _ (SC x AR) + (BS x MS)
Ind" 1 -- 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
0- qqa _ (86.4 ug/g DW x 5 rot/ha) + (292 Ug/g DW x 2000 mt'/ha)
292 ug/g DW (5 rat/ha1* 2000 mt/ha)
•
B. Effect on Soil Biota and Predators of Soil Biota
1. Index of Soil Biota Toxicity (Index 2)
a. Formula
i x BS
Index 2
where:
II - Index 1 = Index of soil concentration
increment (unit less)
BS = Background concentration of pollutant in
soil (ug/g DW)
TB = Soil concentration toxic to soil biota
(Ug/g DW)
A-l
-------
b. Sample calculation - Values were not calculated due
to lack of data.
2. Index of Soil Biota Predator Toxicity (Index 3)
a. Formula
(Ii - 1)(BS x UB) + BB
Index 3 = —= ^
where:
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
x BS
Index 4 =
where :
!]_ = Index 1 = Index of soil concentration
increment (unitless)
BS = Background concentration of pollutant in
soil (ug/g DW)
TP = Soil concentration toxic to plants (ug/g
DW)
b. Sample calculation
0.998 x 292 ug/g DW
n
°' " 454 Ug/g
A-2
-------
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
where:
II - Index 1 = Index of soil concentration
increment (unitless)
BS = Background concentration of pollutant in
soil (ug/g DW)
CO » 2 kg/ha (ug/g)'1 = 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)
b. Sample calculation
0 qa7 _ (0.998-1) x 292 ug/g DW 2 kg/ha
6 Ug/g DW xug/g soil
9 0.0786 ua/g tissue .
* kg/ha i
3. Index of Plant Concentration Increment Permitted by
Phytotoxicity (Index 6)
a. Formula
Index 6 =
where:
PP = Maximum plant tissue concentration
associated with phytotoxicity (ug/g DW)
BP = Background concentration in plant tissue
(pg/g DW)
b. Sample calculation
,. , _ 2745 Ug/g DW
Z1'6 " 127 Ug/g DW
A-3
-------
C. Effect on Herbivorous Animals
1. Index of Animal Toxicity Resulting from Plant Consumption
(Index 7)
a. Formula
x BF
Index 7 =
where:
15 = Index 5 = Index of plant concentration
increment caused by uptake (unit less)
BP = Background concentration in plant tissue
(Ug/g DW)
TA = Feed concentration toxic to herbivorous
animal (ug/g DW)
b. Sample calculation
n IAS - 0.987 x 6 Ug/g DW
°'1A8 " 40 ug/g DW
2. Index of Animal Toxicity Resulting from Sludge Ingest ion
(Index 8)
a. Formula
IfAR-O, IS'55^5
rf AR f o, ia = 2£^-£§
where:
AR = Sludge application race (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 Co be soil
(unicless)
TA = Feed concentration toxic to herbivorous
animal (ug/g DW)
b. Sample calculation
292 DW *°-°5
If AR = 0, 0.365 7 nu
40 Ug/g DW
If AR * 0, 0.108 = 86.4 UR/R DW x 0.05
40 Ug/g DW
A-4
-------
E. Effect on Humans
1. Index of Human Toxicity Resulting from Plant Consumption
(Index 9)
a. Formula
[(£5^- 1) BP x DT] + DI
Index 9 =
ADI
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
(llg/day)
b. Sample calculation (toddler)
0 2ns - f(0'987 - 1) x 28.3 Ug/g DW x 74.5 g/dayl * 825 Ug/dav
4000 U8/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 z DA] + DI
Index 10 = 7^=
ADI
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 [pg/g feed DW)~1)
DA = Daily human dietary intake of affected
animal tissue (g/day DW)
DI = Average daily human dietary intake of
pollutant (ug/day)
ADI = Acceptable daily intake of pollutant
(Ug/day)
A-5
-------
b. Sample calculation (toddler)
», [(0.987-1) ac 6 ug/g DW x 0.03176 ug/g tissueFue/g feed!"1 x 0.97 g/davl * 825 ug/dav
4000 Ug/day
3. Index of Human Toxicity Resulting from Consumption of
Animal Products Derived from Animals Ingesting Soil
(Index 11)
a. Formula
If AR = 0, Index 11 = (BS X GS X "tp* DA) * DI
If AR * 0, Index 11 = CSC x GS x UA x DA) + DI
ADI
where:
AR = Sludge application rate (mt DW/ha)
BS = Background concentration of pollutant in
soil (ug/g DW)
SC = Sludge concentration of pollutant
(Ug/g DW)
GS = Fraction of animal diet assumed to be soil
(unitless)
UA = Uptake slope of pollutant in animal tissue
(Ug/g tissue DW [Ug/g feed DW'1]
DA = Average daily human dietary intake of
affected animal 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)
0.206 =
(86.4 lig/gDW x 0.05 x 0.03176 ue/e tissuefug/g feed]"1 x 0.97g/davDW) + 825 ug/dav
AOOO Ug/day
4. Index of Human Toxicity Resulting from Soil Ingestion
(Index 12)
a. Formula
x BS x DS) + DI
Index 12
ADI
(SC x DS) + DI
Pure sludge ingestion: Index 12 .__
ADI
A-6
-------
where :
II = Index 1 = Index of soil concentration
increment (unitless)
SC = Sludge concentration of pollutant
(Ug/g DW)
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)1
ADI = Acceptable daily intake of pollutant
( Ug/day)
b. Sample calculation (toddler)
0 S71 = (0.998 x 292 ue/g DW x 5 g soil/day) + 825 ue/dav
• 4000 ug/day
Pure sludge:
(86.4 ug/g DW x 5 g soil/day) + 825 ue/dav
4000 Mg/day
5. Index of Aggregate Human Toxicity (Index 13)
a. Formula
Index 13 = I9 + I10 + IU * I12 - ()
where :
Ig = Index 9 = Index of human toxicity
resulting' from plant consumption
(unitless)
= Index 10 = Index of human toxicity
resulting from consumption of animal
products derived from animals feeding on
plants (unitless)
~ 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
()ig/day)
A-7
-------
b. Sample calculation (toddler)
d.569 = (0.205 * 0.206 * 0.206 * 0.571) -
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
------- |