FINAL DRAFT
United States
Environmental Protection
Agency
4>EPA Research and
Development
HEALTH AND ENVIRONMENTAL EFFECTS DOCUMENT
FOR ENDOTHALL
Prepared for
OFFICE OF SOLID WASTE AND
EMERGENCY RESPONSE
Prepared by
Environmental Criteria and Assessment Office
Office of Health and Environmental Assessment
U.S. Environmental Protection Agency
Cincinnati, OH 45268
DRAFT: DO NOT CITE OR QUOTE
NOTICE
cument 1s a preliminary draft. It has not been formally released
Environmental Protection Agency and should not at this stage be
o represent Agency policy. It 1s being circulated for comments
ilcal accuracy and policy Implications.
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DISCLAIMER
This report 1s an external draft for review purposes only and does not
constitute Agency policy. Mention of trade names or commercial products
does not constitute endorsement or recommendation for use.
11
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PREFACE
Health and Environmental Effects Documents (HEEOs) are prepared for the
Office of Solid Waste and Emergency Response (OSWER). This document series
Is Intended to support listings under the Resource Conservation and Recovery
Act (RCRA) as well as to provide health-related limits and goals for emer-
gency and remedial actions under the Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA). Both published literature and
Information obtained for Agency Program Office files are evaluated as they
pertain to potential human health, aquatic life and environmental effects of
hazardous waste constituents. The literature searched for In this document
and the dates searched are Included In "Appendix: Literature Searched."
Literature search material Is current up to 8 months previous to the final
draft date listed on the front cover. Final draft document dates (front
cover) reflect the date the document Is sent to the Program Officer (OSWER).
Several quantitative estimates are presented provided sufficient data
are available. For systemic toxicants, these Include Reference doses (RfDs)
for chronic and subchronlc exposures for both the Inhalation and oral
exposures. The subchronlc or partial lifetime RfD 1s an estimate of an
exposure level that would not be expected to cause adverse effects when
exposure occurs during a limited time Interval I.e., for an Interval that
does not constitute a significant portion of the Hfespan. This type of
exposure estimate has not been extensively used, or rigorously defined as
previous risk assessment efforts have focused primarily on lifetime exposure
scenarios. Animal data used for subchronlc estimates generally reflect
exposure durations of 30-90 days. The general methodology for estimating
subchronlc RfDs 1s the same as traditionally employed for chronic estimates,
except that subchronlc data are utilized when available.
In the case of suspected carcinogens, RfDs are not estimated. Instead,
a carcinogenic potency factor, or q-j* (U.S. EPA, 1980), Is provided.
These potency estimates are derived for both oral and Inhalation exposures
where possible. In addition, unit risk estimates for air and drinking water
are presented based on Inhalation and oral data, respectively.
Reportable quantities (RQs) based on both chronic toxlclty and carclno-
genldty are derived. The RQ Is used to determine the quantity of a hazard-
ous substance for which notification Is required In the event of a release
as specified under the Comprehensive Environmental Response, Compensation
and Liability Act (CERCLA). These two RQs (chronic toxlclty and carclno-
genldty) represent two of six scores developed (the remaining four reflect
1gn1tab1l1ty, reactivity, aquatic toxlclty, and acute mammalian toxlclty).
Chemical-specific RQs reflect the lowest of these six primary criteria. The
methodology for chronic toxlclty and cancer based RQs are defined In U.S.
EPA, 1984 and 1986a, respectively.
111
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EXECUTIVE SUMMARY
Endothall (145-73-3) 1s a colorless or white solid at room temperature
(Martin and Worthing, 1979; Worthing and Walker, 1983). It Is soluble In
common organic solvents and soluble 1n water (Worthing and Walker, 1983;
Hartley and K1dd, 1983). Pennwalt Corp. 1n Wyandotte, MI, 1s the only
current domestic manufacturer of this compound (SRI, 1987; USITC, 1987).
Its current U.S. production volume 1s not available. Various formulations
of endothall are used as preemergence and postemergence herbicides, turf
herbicides, aquatic herbicides and alglddes, deslccants for alfalfa and
clover, and cotton harvest aids (Worthing and Walker, 1983; WSSA, 1983;
Melster, 1988). Tradenames Include Accelerate, Aquathol K, Des-1-cate,
Herbicide 273 and Hydrothol 191 {Melster, 1988).
If released to the atmosphere, endothall Is expected to exist predomi-
nantly In aerosol form and may be removed by either wet or dry deposition.
Photolysis Is not expected to be an environmentally relevant fate process
(Relnert and Rodgers, 1984). If released to soil or water, endothall would
be subject to rapid blodegradatlon under appropriate conditions. Field and
laboratory studies Indicate that endothall generally has a half-life of <1
week 1n surface waters under aerobic conditions (S1ms1man et al., 1976;
Relnert et al., 1985, 1986, 1988; S1kka and R1ce, 1973; Relnert and Rodgers,
1987; Holmberg and Lee, 1976; Langeland and Warner, 1986). This compound
blodegrades more slowly In water under anaerobic conditions and has a
half-life of ~2 months (Slmslman et al., 1976). Arthrobacter sj>., Isolated
from sediment, metabolized 14C-endothall under aerobic conditions and
Incorporated the 14C Into glutamlc, aspartlc and citric adds, and to a
lesser extent alanlne, phosphate esters (not positively Identified) and
1v
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other unidentified compounds (S1kka and Saxena, 1973). Endothall 1s not
expected to degrade chemically, volatilize or adsorb significantly In water
or soil (Relnert and Rodgers, 1984; Relnert et al., 1988; S1ms1man and
Chesters, 1975; Swann et al., 1983). The blodegradatlon half-life of this
chemical In soil Is <7 days and 1t Is expected to persist more 1n soils with
high adsorption capability. Rapid blodegradatlon 1s expected to limit the
extent of leaching through soil.
The most common route of human exposure to endothall Is probably dermal
contact by workers Involved In the manufacture, handling or application of
the herbicide (HSDB, 1988). The general public could potentially be exposed
by Ingestlon of contaminated crops. Monitoring data for endothall In
environmental media (air, water, soil and food) were not located 1n the
available literature dted In Appendix A.
The potassium and sodium salts of endothall are the forms least toxic to
both aquatic vertebrates and Invertebrates, with 96-hour LC s Of >IQQ
mg/l. In contrast, 96-hour LC5Qs for the amlne and copper salts are <1
mg/i for a variety of aquatic organisms. Water hardness did not Influence
the toxlclty of dlsodlum or dlamlne salts to bluegllls (Inglls and Davis,
1973) and pH did not affect the toxlclty of Aquathol K to bluegllls (Mayer
and Ellersleck, 1986). The toxlclty of Aquathol K to blueglll sunflsh
Increased 5-fold when the test temperature Increased from 7 to 24°C (Mayer
and Ellersleck, 1986).
The 14-day LC5Q of endothall to juvenile Chinook salmon, Onchorynchus
tshawytscha. was 62.5 ppm (Llgourl et al., 1983). Surviving fish demon-
strated poor survival when transferred to seawater but good survival when
transferred to freshwater. The 10-day growth EC5Qs for various species of
marine algae exposed to the amlne and dlpotassium salts ranged from 225-3000
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ppm (Walsh, 1972). No short- or long-term effects were observed among
natural populations of organisms 1n ponds or reservoirs treated with <5
mg/i endothall.
Experimental evidence suggests that endothall 1s not likely to bloaccu-
mulate 1n aquatic organisms. S1kka et al. (1975) reported that bluegllls
took up <1% of the available herbicide from water over a 96-hour period.
Isensee (1976) reported bloaccumulatlon ratios of 63, 36, 150 and 10 for
algae, snails, daphnlds and fish. Serns (1977) was unable to detect
endothall residues 1n tissues of bluegllls from a pond that had been treated
3 days earlier with endothall to give a concentration of 5 mg/i. Relnert
and Rodgers (1986) were unable to detect endothall residues In tissues of
bluegllls from a reservoir that had been treated 7 days earlier with 2
mg/l endothall. Relnert et al. (1988) reported BCFs of 3.9, 12.1 and
768.9 for the dlpotasslum salt of endothall In watermllfoll, but discounted
the highest value because of experimental errors.
Data obtained from rats of both sexes treated with a single oral dose of
14C-endothall suggest that gastrointestinal absortlon 1s poor (Soo et al.,
1967). Peak tissue concentrations occurred within 1 hour In all tissues
sampled except the Intestine. The absorbed radioactivity occurred predomi-
nately 1n the stomach and Intestine (-99% of the administered radioactiv-
ity). About 1% of the administered radioactivity occurred 1n the liver and
kidneys. Radioactivity was not found In fat or milk, and was essentially
eliminated from all tissues within 72 hours. At least 85% of the adminis-
tered dose was excreted 1n the feces, but ~20% of this was unchanged com-
pound and 80% was bound In some form. It seems more likely that the bound
form 1s endothall that Is adsorbed onto gastrointestinal contents rather
than an endothall conjugate. Small quantities were excreted In the urine
(~6%), apparently as unchanged compound, and In the breath as CO- (~3%).
v1
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Minimal data were located In the available literature regarding the
health effects of endothall. Acute toxlclty appears to be substantially
greater for the add form than for the dlsodlum salt. Oral LD5Q values
for rats of 38-57 mg/kg have been reported for the add form (Worthing and
Walker, 1983; Galnes and Under, 1986) and 182-197 mg/kg have been reported
for the dlsodlum salt. Acute exposure to large doses Is extremely
Irritating and causes erosion and hemorrhage of the stomach (Allender, 1983;
Brleger, 1953b).
Subchronlc data suggest that dogs may be more sensitive than rats to
oral exposure to endothall. In a dietary study, rats succumbed to dosages
of the Ion of 400 mg/kg/day and exhibited liver and kidney lesions at 40
mg/kg/day (Brleger, 1953a). Dogs treated by capsule, however, died at 20
mg/kg/day dlsodlum endothall (16 mg/kg/day endothall 1on) and had congestion
and edema of the stomach at 0.8 mg/kg/day of endothall Ion (Brleger,
1953b). The Investigators suggested that the lesions In the stomach
resulted from the administration of the undiluted test substance without
food.
There are notable discrepancies between the subchronlc and chronic data.
For example, no toxic effects were reported In a 2-year dietary study where
rats were exposed to 2500 ppm dlsodlum endothall (100 mg/kg bw/day of endo-
thall 1on) (Brleger, 1953b). In a 2-year dietary study using dogs (4/dose),
elevated relative and absolute stomach and small Intestine weights were
Increased with dlsodlum endothall at 300 and 800 ppm (6 and 16 mg/kg/day of
endothall 1on), but no effects were observed at 100 ppm (2 mg/kg/day of the
Ion) (Keller, 1965; Penwalt Agchem, n.d.).
Developmental toxldty studies using rats suggest that the dams are more
susceptible than the fetuses to oral administration of endothall (Science
vll
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Applications, Inc., 1982). In a dietary study pregnant rats were given 0,
8, 16 or 24 mg endothall 1 on/kg/day on gestation days 6-19. Maternal deaths
occurred at the two higher doses but the fetuses of the surviving dams
exhibited no signs of teratogenldty or fetotoxldty. A NOAEL of 8
mg/kg/day was Identified from this study for teratogenldty based on
maternal effects.
In a 3-generat1on reproductive study, no effects were observed when rats
were exposed to dlsodlum endothall 1n the diet that provided a dosage of
endothall Ion at 4 mg/kg/day (Scientific Associates, 1965). In the same
3-generat1on study, however, pups 1n the 12 mg/kg/day group had reduced body
weights and pups 1n the 100 mg/kg/day group died within a week of birth.
Endothall has not been adequately tested for carclnogenldty. There was
no evidence of carclnogenldty 1n rats fed diets containing dlsodlum
endothall at <2500 ppm {100 mg/kg/day of the 1on) for 2 years 1n an early
study (Brleger, 1953b). Endothall Induced transformation of BALB/c 3T3
cells (LUton B1onet1cs, Inc., 1981). Endothall was not mutagenlc In
microorganisms (Andersen et al., 1972; Remondelll et al., 1986;
Microbiological Associates, 1980a; Sandier and Ham1lton-Byrd, 1981) and 1n
human lymphocytes (Vlgfusson, 1981). Mixed results were obtained In
Drosophla (Wilson et al., 1956; Sandier and Hamllton-Byrd, 1981).
The NOEL for gastrointestinal effects 1n dogs from the chronic oral dog
study (Keller, 1965; Pennwalt Agchem, n.d.) was used as the basis for a
verified RfD of 0.02 mg/kg/day for endothal. This RfD 1s adopted as the RfD
for chronic oral exposure as well as subchronlc oral exposure to endothall
for the purposes of this document. An RQ of 1000 was calculated from the
effect level for gastrointestinal effects In the same study. Endothall 1s
assigned to EPA Group D because of Insufficient animal carclnogenldty data;
therefore, no q,* or cancer-based RQ can be derived for endothall.
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TABLE OF CONTENTS
Page
1. INTRODUCTION 1
1.1. STRUCTURE AND CAS NUMBER . . 1
1.2. PHYSICAL AND CHEMICAL PROPERTIES 1
1.3. PRODUCTION DATA 2
1.4. USE DATA 2
1.5. SUMMARY 2
2. ENVIRONMENTAL FATE AND TRANSPORT 4
2.1. AIR 4
2.1.1. Chemical Degradation 4
2.1.2. Physical Removal Processes 4
2.2. WATER 4
2.2.1. Chemical Degradation 4
2.2.2. Volatilization 4
2.2.3. Adsorption 4
2.2.4. Persistence 5
2.3. SOIL ' • . . 9
2.3.1. Chemical Degradation 9
2.3.2. Volatilization 9
2.3.3. Persistence 9
2.3.4. Adsorption 10
2.4. SUMMARY 10
3. EXPOSURE 12
4. ENVIRONMENTAL TOXICOLOGY 13
4.1. AQUATIC TOXICOLOGY 13
4.1.1. Acute Toxic Effects on Fauna 13
4.1.2. Chronic Effects on Fauna 24
4.1.3. Effects on Flora 26
4.1.4. Effects on Bacteria 28
4.2. TERRESTRIAL TOXICOLOGY 28
4.2.1. Effects on Fauna 28
4.2.2. Effects on Flora 28
4.3. FIELD STUDIES 28
4.4. AQUATIC RISK ASSESSMENT . 30
4.5. SUMMARY 31
1x
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TABLE OF CONTENTS (cont.)
Page
5. PHARMACOKINETCS 33
5.1. ABSORPTION 33
5.2. DISTRIBUTION 34
5.3. METABOLISM 35
5.4. EXCRETION 35
5.5. SUMMARY 36
6. EFFECTS 37
6.1. SYSTEMIC TOXICITY 37
6.1.1. Inhalation Exposure 37
6.1.2. Oral Exposure 37
6.1.3. Other Relevant Information 38
6.2. CARCINOGENICITY 39
6.2.1. Inhalation 39
6.2.2. Oral 39
6.2.3. Other Relevant Information 39
6.3. MUTAGENICITY 39
6.4. TERATOGENICITY 39
6.5. OTHER REPRODUCTIVE EFFECTS 41
6.6. SUMMARY 41
7. EXISTING GUIDELINES AND STANDARDS 44
7.1. HUMAN 44
7.2. AQUATIC 44
8. RISK ASSESSMENT 45
8.1. CARCINOGENICITY 45
8.1.1. Inhalation 45
8.1.2. Oral 45
8.1.3. Other Routes. . . 45
8.1.4. Weight of Evidence 45
8.1.5. Quantitative Risk Estimates 45
8.2. SYSTEMIC TOXICITY 46
8.2.1. Inhalation Exposure 46
8.2.2. Oral Exposure 46
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TABLE OF CONTENTS (cont.)
Page
9. REPORTABLE QUANTITIES 48
9.1. BASED ON SYSTEMIC TOXICITY 48
9.2. BASED ON CARCINOGENICITY 48
10. REFERENCES 52
APPENDIX A: LITERATURE SEARCHED 64
APPENDIX B: SUMMARY TABLE FOR ENDOTHALL 67
APPENDIX C: DOSE/DURATION RESPONSE GRAPH(S) FOR EXPOSURE TO
ENDOTHALL 68
xl
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LIST OF TABLES
No. Title Page
4-1 Median Response Concentration for F1sh and Amphibians
Exposed to Endothall 14
4-2 Median Response Concentration for Invertebrates Exposed to
Endothall 22
6-1 Mutagen1c1ty and Genotoxldty Summary Table for Endothall . . 40
9-1 Toxldty Summary for Oral Exposure to Endothall Using the
Beagle Dog. 49
9-2 Composite Scores for Endothall Ion Using the Dog 50
9-3 Endothall: Minimum Effective Dose (MED) and Reportable
Quantity (RQ) 51
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LIST OF ABBREVIATIONS
ADI Acceptable dally Intake
ATP Adenoslne trlphosphate
BCF B1oconcentrat1on factor
BR B1oaccumulat1on ratio
BSP Bromosulfophthaleln
bw Body weight
CAS Chemical Abstract Service
DUEL Drinking water exposure level
ECso Concentration effective to 50% of recipients
(and all other subscripted concentration levels)
GSH Reduced glutathlone
HA Health Advisory
150 Median Inhibition concentration
Koc Soil sorptlon coefficient standardized with respect
to organic carbon
Kp Sediment-water partition coefficient
LCso Concentration lethal to 50% of recipients
(and all other subscripted dose levels)
LD5Q Dose lethal to 50% of recipients
NOAEL No-observed-adverse-effect level
NOEL No-observed-effect level
ppm Parts per million
RfD Reference dose
RQ Reportable quantity
RVd Dose-rating value
RVe Effect-rating value
SGOT Serum glutamlc oxaloacetlc transamlnase
SGPT Serum glutamlc pyruvlc transamlnase
X111
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1. INTRODUCTION
1.1. STRUCTURE AND CAS NUMBER
Endothall Is currently referred to by CAS as 7-oxab1cyclo[2.2.l]heptane-
2.3-d1carboxyl1c acid (SANSS, 1987). Endothall 1s also known as endothal
and 3,6-endo-epoxycyclohexane-1,2-d1carboxyl1c add (WSSA, 1983). Trade-
names Include Accelerate. Aquathol K, Des-1-cate, Herbicide 273 and
Hydrothol 191 (Melster, 1988). Discontinued names Include Hydout, Hydro-
thol, Hydrothol 47 and Nlagrathal (Melster, 1988). The structure, CAS
Registry number, empirical formula and molecular weight for this compound
are as follows:
H 0
^CHCOOH
9
H2C | CHCOOH
H
CAS number: 145-73-3
Empirical formula: CgH1Q05
Molecular weight: 186.16
1.2. PHYSICAL AND CHEMICAL PROPERTIES
Endothall, which 1s available as a hydrate, 1s a white or colorless
solid at room temperature (Martin and Worthing, 1979; Worthing and Walker,
1983). It 1s soluble 1n water, acetone, dloxane, methanol, Isopropanol and
ether (Worthing and Walker. 1983; Hartley and Kldd, 1983). It 1s
noncorroslve to metals and 1s nonflammable (Worthing and Walker, 1983).
Selected physical and chemical properties are as follows (Worthing and
Walker. 1983; WSSA, 1983; Relnert and Rodgers, 1984):
Melting point: 144°C
Boiling point: not available
0168d -1- 04/19/89
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Vapor pressure: not available
Water solubility at 20°C: 100,000 mg/l
Log Kow: 1.91
pKal: 3.4
pKa2: 6.7
Density at 20°C: 1.431 g/cm3
The hydrate of endothall forms Its anhydride at 90°C. It 1s a dibasic acid
and forms water soluble amlne and alkali metal salts. It 1s stable In
acids. Of the three stereolsomers of this chemical, the endocls Isomer Is
the most effective herbicide (Worthing and Walker, 1983).
1.3. PRODUCTION DATA
Pennwalt Corporation In Wyandotte, MI, 1s the only domestic manufacturer
of endothall (SRI, 1987; USITC, 1987). It 1s made by the D1els-Alder
condensation of furan and malelc anhydride (Worthing and Walker, 1983).
Data pertaining to the amount of endothall produced or used 1n the United
States were not located In the available literature.
1.4. USE DATA
The sodium, potassium and amlne salts of endothall are used as pre-
emergence and postemergence herbicides, turf herbicides, aquatic herbicides,
alglddes, desslcants for alfalfa and clover, and cotton harvest aids
(Worthing and Walker, 1983; WSSA, 1983; Melster, 1988).
1.5. SUMMARY
Endothall (145-73-3) 1s a colorless or white solid at room temperature
(Martin and Worthing, 1979; Worthing and Walker, 1983). It 1s soluble In
common organic solvents and soluble 1n water (Worthing and Walker, 1983;
Hartley and Kldd, 1983). Pennwalt Corp. In Wyandotte. MI, 1s the only
current domestic manufacturer of this compound (SRI, 1987; USITC, 1987).
0168d -2- 04/19/89
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Its current U.S. production volume Is not available. Various formulations
of endothall are used as preemergence and postemergence herbicides, turf
herbicides, aquatic herbicides and alglddes, deslccants for alfalfa and
clover, and cotton harvest aids (Worthing and Walker, 1983; WSSA, 1983;
Melster, 1988). Tradenames Include Accelerate, Aquathol K, Des-1-cate,
Herbicide 273 and Hydrothol 191 (Melster, 1988).
0168d -3- 06/22/89
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2. ENVIRONMENTAL FATE AND TRANSPORT PROCESSES
2.1. AIR
2.1.1. Chemical Degradation. Endothall Is stable to photolysis (Relnert
and Rodgers, 1984). Pertinent data regarding other chemical degradation
processes 1n the atmosphere were not located In the available literature
cited 1n Appendix A.
2.1.2. Physical Removal Processes. A "negligible" vapor pressure for
endothall (Slmslman et al., 1976) suggests that this compound may not exist
1n the vapor form 1n the atmosphere (Elsenrelch et al., 1981). Dry deposi-
tion of aerosols containing endothall may be an Important removal process.
The relatively high water solubility of endothall suggests that this
compound may also be removed from the atmosphere by wet deposition.
2.2. WATER
2.2.1. Chemical Degradation. Endothall 1s stable to oxidation, hydroly-
sis and photolysis (Relnert and Rodgers, 1984; Relnert et al., 1988).
2.2.2. Volatilization. Using the method of Nine and Mookerjee (1975),
Henry's Law constant for endothall has been estimated to be ~3xlO~12
atm-m3/mole at 25°C. This value of Henry's Law constant suggests that
volatilization of endothall from water surfaces would be an Insignificant
fate process.
2.2.3. Adsorption. Relnert and Rodgers (1984) determined the sediment/
water partition coefficient (Kp) for endothall (dlpotasslum salt) 1n two
different sediment/water systems. Sediment obtained from Pat Mayse Lake 1n
northeastern Texas was predominantly sand with 0.683% organic carbon
content, and sediment obtained from Roselawn Cemetery Pond In north central
Texas was predominantly clay with 1.29% organic carbon content. Endothall
was added to the systems at concentrations that ranged between 2.0 and 6.3
0168d -4- 04/19/89
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mg/l. After equilibration between the phases was achieved, the mean Kp
value for endothall was determined to be 0.937 1n the lake water system and
1.42 1n the pond water system. These values corresponded to K values of
137 and 110, respectively. Analysis of data obtained by S1ms1man and
Chesters (1975) using sediment/water samples from Lake Tomahawk 1n southern
Michigan Indicate that endothall had K values ranging between 2.7 and
6.0. These experimental data Indicate that adsorption to suspended solids
and sediments 1n water should play a relatively minor role 1n the fate of
endothall In aquatic systems.
2.2.4. Persistence. Blodegradatlon and blotransformatlon are the
dominant removal processes for endothall 1n aquatic systems (Relnert and
Rodgers, 1984; S1ms1man et al., 1976). Endothall (dlpotasslum salt) at an
Initial concentration of 0.41 mg/l was applied to a recreational area 1n
Pat Mayse Lake, an ol1gomesotroph1c lake In northeast Texas. Subsequent
monitoring data Indicated that endothall had a half-life of 0.33 days
(Relnert et al., 1988). Dilution may have played an Important role In the
reduction of the herbicide level 1n the treated area, since only a portion
of the water body (1.7% of total surface area) was treated and transport
from treated to nontreated areas was possible. S1kka and Rice (1973)
studied the persistence of endothall (dlpotasslum salt) 1n pond water, both
In aquaria and under field conditions. In a pond treated to give concentra-
tions of 2 mg/i endothall, serial samples were taken and nondetectable
levels were found 1n the water and top 1 Inch of the hydrosoll (sediment) 36
days after treatment. In the aquaria treated to give concentrations of 2
and 4 mg/l endothall, 50% loss 1n concentration was observed In ~4 days,
with nondetectable levels existing after 7 days. In autoclaved pond water,
no degradation of endothall had occurred after 9 days; however, 1 day after
application 6.9% of the radlolabeled endothall appeared In the sediment.
0168d -5- 04/19/89
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Figures 2-1 and 2-2 show the respective disappearance patterns of endothall
from the pond and aquaria. In other pond studies carried out under field
conditions, the half-life for the disappearance of endothall (dlpotasslum
salt) was found to range between 4.1 and 12 days (Relnert and Rodgers, 1987;
Holmberg and Lee, 1976; Langeland and Warner, 1986). Both the dlpotasslum
and the dlamlne salts persisted <7 days when used In Gatan Lake, Panama
(Relnert and Rodgers, 1987). When static greenhouse experimental pools were
treated with endothall (dlpotasslum salt) at levels of 0.03, 1.6 and 4.5
mg/i, the average half-life of this compound was determined to be 4.01
days (Relnert et al., 1985). The pools contained water, sediment and
Eurasian watermllfoll. In a laboratory static shake flask study, Relnert et
al. (1986) studied the blotransformatlon and blodegradatlon of endothall
(dlpotasslum salt) at levels of 0.5, 2.0 and 4.0 mg/l In water samples
obtained from Pat Mayse Lake (In Texas). Based on the evolution of radlo-
labeled-CO-, a first-order blotransformatlon rate coefficient of 0.083
days'1 and half-life for blotransformatlon of 8.45 days were calculated.
In various field studies, endothall (dlpotasslum salt) was found to
persist In sediment between 0 and 7 days, while the amlne salt has been
shown to persist for >21 days (Relnert and Rodgers, 1987). It has also been
shown that a reduction of the dissolved oxygen content of water could have a
significant effect on the degradation of endothall. In a simulated lake
Impoundment, 72% of added endothall persisted 1n water for 30 days because
of prolonged anoxlc conditions following weedklll. Rapid disappearance
occurred only after restoration of oxygenated conditions (S1ms1man et al.,
1976). Short-term Incubation of 14C-endothall with an Arthrobacter sp_.,
Isolated from sediment revealed that 14C was Incorporated Into glutamlc,
aspartlc and citric adds and to a lesser extent alanlne, phosphate esters
(not positively Identified) and other unidentified compounds.
0168d -6- 04/19/89
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2.00-
WATER
HVDROSOIL
Q46
24 28 32 36 40 44
DAYS AFTER TREATMENT
FIGURE 2-1
Endothall Residues 1n Water and the Top 1-Inch of Hydrosoll of a Treated
Farm Pond, with Time. (The bars represent the range of duplicate values.)
Source: S1kka and R1ce, 1973
0168d
-7-
04/11/89
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• • WATER-4ppm
» * WATER-2 ppm
«..—_« MYDROSOIU- 4 ppm
•——•• MYOfiOSOIL- 2 ppm
12 16 20 24 28
0*VS AFTER TREATMENT
FIGURE 2-2
Endothall Residues In Water and Hydrosoll of Aquaria Treated with 2 and 4
ppm of the Herbicide. (The bars represent the range of duplicate values.)
Source: S1kka and R1ce, 1973
0168d
-8-
04/11/89
-------
I40-glutam1c acid accounted for a large proportion of the 14C assimi-
lated Into the cells. Apparently, radlolabeled C was Incorporated Into
glutamlc acid by the trlcarboxyllc add cycle and an alternate, unknown
pathway following Initial splitting of the oxablcyclo ring {Slkka and
Saxena, 1973).
2.3. SOIL
2.3.1. Chemical Degradation. Chemical degradation processes are not
expected to contribute significantly to the loss of this compound from soil
(Slmslman et al., 1976).
2.3.2. Volatilization. The relatively high water solubility and
negligible vapor pressure of endothall suggest that volatilization from soil
surfaces would not be a significant fate process.
2.3.3. Persistence. As In aquatic environments, degradation of endothall
1n soil appears to be due primarily to mlcroblal activity. Mlcroblal degra-
dation rather than chemical degradation 1s evidenced by the observations
that 1) reduction of soil moisture and temperature markedly reduced
endothall degradation, 2) treatment of soils with nonlabeled endothall and
nutrients followed by labeled endothall led to Increased degradation
compared with samples not similarly pretreated, and 3) addition of mlcroblal
Inhibitors, such as pentachlorophenol, to soil reduced degradation {Slmslman
et al., 1976; Tweedy and Houseworth, 1976). Endothall reportedly persists
2-7 weeks 1n soil (Tweedy and Houseworth, 1976). Approximately 70% of
14C-endothall added to an Ontario soil was evolved as 14CO? In 7 days;
the remaining endothall existed 1n a nonextractable form, probably no longer
as endothall (Slmslman et al., 1976). On a clay loam soil, an 85% loss of
14C-endothall was observed In 14 days. Slower rates were observed 1n
0168d -9- 04/19/89
-------
sandy soil, which may have had a higher organic content than did the clay
loam, resulting 1n greater adsorption and slower degradation (Slmslman et
al., 1976).
2.3.4. Adsorption. Experimentally determined K values of 2.7-137
(see Section 2.2.3.) Indicate high mobility 1n soil (Swann et al., 1983).
However, fairly rapid degradation 1n the soil column Is expected to limit
the extent of leaching. Nevertheless, some potential exists for groundwater
contamination.
2.4. SUMMARY
If released to the atmosphere, endothall 1s expected to exist predomi-
nantly 1n aerosol form and may be removed by either wet or dry deposition.
Photolysis 1s not expected to be an environmentally relevant fate process
(Relnert and Rodgers, 1984). If released to soil or water, endothall would
be subject to rapid blodegradatlon under appropriate conditions. Field and
laboratory studies Indicate that endothall generally has a half-life of <1
week In surface waters under aerobic conditions (Slmslman et al., 1976;
Relnert et al., 1985, 1986, 1988; Slkka and R1ce, 1973; Relnert and Rodgers,
1987; Holmberg and Lee, 1976; Langeland and Warner, 1986). This compound
blodegrades more slowly 1n water under anaerobic conditions and has a
half-life of ~2 months (Slmslman et al., 1976). Arthrobacter s_£., Isolated
from sediment, metabolized 14C-endothall under aerobic conditions and
Incorporated the 14C Into glutamlc, aspartlc and dtrlc adds, and to a
lesser extent alanlne, phosphate esters (not positively Identified) and
other unidentified compounds (Slkka and Saxena, 1973). Endothall 1s not
expected to degrade chemically, volatilize or adsorb significantly 1n water
or soil (Relnert and Rodgers, 1984; Relnert et al., 1988; Slmslman and
Chesters, 1975; Swann et al., 1983). The blodegradatlon half-life of this
0168d -10- 04/19/89
-------
chemical 1n soil 1s <7 days and H Is expected to persist more In soils with
high adsorption capability. Rapid blodegradatlon 1s expected to limit the
extent of leaching through soil.
0168d -11- 04/19/89
-------
3. EXPOSURE
The most common route of human exposure to endothall 1s probably dermal
contact by workers Involved In the manufacture, handling or application of
the herbicide (HSDB, 1988). The general public could potentially be exposed
by Ingestlon of contaminated crops. Monitoring data for endothall In
environmental media (air, water, soil and food) were not located In the
available literature cited 1n Appendix A.
0168d -12- 04/11/89
-------
4. ENVIRONMENTAL TOXICOLOGY
4.1. AQUATIC TOXICOLOGY
4.1.1. Acute Toxic Effects on Fauna. The acute toxlclty of a variety of
endothall products to fish and one amphibian are presented In Table 4-1.
These data reveal that the potassium and sodium salts of endothall are the
forms least toxic to aquatic vertebrates. Typical 96-hour LC5Qs for fish
exposed to the dlsodlum salt were 102 mg/l for blueglll sunflsh, Lepomls
macrochlrus {Inglls and Davis, 1973), 105 mg/l for redslded shiner,
Notropls umbratnis, and 125 mg/i for redear sunflsh, Lepomls mlcrolophus
(Folmar, 1977). Typical 96-hour LC5Qs for fish exposed to the potassium
salt were 440 mg/l for blueglll sunflsh (Mayer and Ellersleck, 1986) and
372 mg/B. for goldfish, Carraslus auratus (Berry, 1984). Amlne and copper
salts generated 96-hour LC5Qs of <1 mg/l.
Inglls and Davis (1973) reported that water hardness did not Influence
the toxldty of the dlsodlum or dlamlne salt to blueglll sunflsh. Mayer and
Ellersleck (1986) demonstrated that pH was not a factor affecting the
toxlclty of Aquathol K to blueglll sunflsh, but that an Increase In the test
temperature from 7 to 24°C Increased the toxlclty of Aquathol K 5-fold. In
the only study In which the toxlclty of an endothall product to an amphibian
was assessed, Mayer and Ellersleck (1986) reported a static acute 96-hour
LC5Q of 1.2 mg/i for Fowler's toad, Bufo woodhousel fowlerl. exposed to
Hydrothol 191.
The acute toxlclty of a variety of endothall products to aquatic
Invertebrates 1s presented 1n Table 4-2. The potassium and sodium salts
were less toxic to aquatic Invertebrates than other endothall salts, as they
were to aquatic vertebrates. Mayer and Ellerselck (1986) reported a 96-hour
LC50 ^or scud» Gammarus fasdatus, exposed to the potassium salt of 313 mg/l,
0168d -13- 04/19/89
-------
TABLE 4-1
Median Response Concentrations for Fish and Anphtblans Exposed to Endothall
CO
0.
Species
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
.[_, Lepomls macrochlrus
1 Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
o Lepomls nacrochlrus
^ Blueglll sunflsh
^ Lepomls macrochlrus
Median Response Concentration*
Chemical
dlsodlum salt
(liquid formulation)
dlsodlum salt
(granular formulation)
dlamlne salt
dlamlne salt
dlsodlum salt
(19. 2X liquid formulation)
dlsodlum salt
(19. 2X liquid formulation)
dlsodlum salt
(19. 2X liquid formulation)
dlamlne salt
dlamlne salt
dlamlne salt
dlamlne salt
dlamlne salt
dlamlne salt
dlamlne salt
Test
Method
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static,
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static,
unmeasured
static,
unmeasured
static,
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
24-Hour
450 ppm a.e.
650 ppm a.e.
1.12 ng/t
(1.06-1.19)
0.90 ng/t
(0.85-0.95)
277 ng/t
(234-328)
249 ng/t
(222-279)
280 ng/t
(242-324)
0.91 ng/t
(0.79-1.05)
0.84 ng/t
(0.76-0.92)
0.78 ng/t
(0.72-0.84)
0.88 ng/t
(0.81-0.96)
1.02 ng/t
(0.95-1.10)
0.87 ng/t
(0.79-0.95)
1.49 ng/t
(1.21-1.83)
48 -Hour
280 ppm a.e.
280 ppm a.e.
1.03 ng/t
(0.95-1.11)
0.90 ng/t
(0.85-0.95)
219 ng/t
(198-242)
181 ng/t
(166-197)
196 ng/t
(178-215)
0.63 ng/t
(0.56-0.71)
0.78 ng/t
(0.72-0.87)
0.68 mg/t
(0.62-0.75)
0.84 mg/t
(0.77-0.91)
0.80 mg/t
(0.72-0.88)
0.87 mg/t
(0.78-0.96)
1.34 mg/t
(1.17-1.53)
96 -Hour
NR
NR
NR
NR
140 ng/t
(126-156)
105 ng/t
(88-125)
102 ng/t
(84-124)
NR
NR
NR
NR
NR
NR
NR
Comments
hardness = 29 mg/t
hardness <= 29 ng/t
temperature = 24'C
hardness = 368.4 mg/t
temperature = 24*C
hardness = 368.4 ng/t
temperature = 24*C
hardness = 52.2 mg/t
temperature = 24*C
hardness = 208.7 mg/t
temperature = 24'C
hardness = 365.2 mg/t
temperature = 24'C
hardness = 52.5 mg/t
temperature = 24*C
hardness =52.5 ng/t
temperature = 24°C
hardness =210 mg/t
temperature = 24'C
hardness = 210 ng/t
temperature <= 24'C
hardness = 368.4 mg/t
temperature = 24'C
hardness = 368.4 mg/t
temperature = 24'C
hardness = 52.5 mg/t
Reference
Hughes and .
Davis. 1965
Inglls and
Davis. 1973
Inglls and
Davis, 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis, 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
00
10
-------
TABLE 4-1 (cont.)
o
—1
00
CL
1
I
O
CO
Median Response Concentration*
Species
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunftsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomts macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Chemical
dlamlne salt
dlamlne salt
dlamlne salt
dlpotasslum salt
cocoamlne salt
cocoamlne salt
dlsodlum salt
(liquid formulation)
dlsodlum salt
dlsodlum salt
dlsodlum salt
(liquid formulation)
dlsodlum salt
dlsodlum salt
(granular formulation)
dlsodlum salt
(granular formulation)
copper salt
(25X wet table powder)
Test
Method
static.
unmeasured
static,
unmeasured
static.
unmeasured
static
static
static
static
static
static
static
static
static
static
static
24-Hour
1.09 mg/t
(1.01-1.18)
1.02 mg/t
(0.94-1.10)
1.02 mg/t
(0.94-1.11)
428 mg/t
0.8 mg/t
0.3 mg/t
NR
NR
NR
NR
NR
NR
NR
6.70 mg/t
(5.33-8.46)
48-Hour
1.02 mg/t
(0.96-1.09)
0.94 mg/t
(0.90-0.98)
1.00 mg/t
(0.92-1.08)
268 mg/t
0.8 mg/t
0.3 mg/t
NR
NR
NR
450 mg/t
NR
NR
650 mg/t
NR
96-Hour
NR
NR
NR
NR
NR
NR
NR
180 mg/t
NR
280 mg/t
125-150 mg/t
NR
280 mg/t
3.33 mg/t
(2.51-4.4)
Comments
temperature •= 24*C
hardness = 52.5 mg/t
temperature 24°C
hardness = 210 mg/t
temperature 24*C
hardness =210 mg/t
NC
NC
NC
no observed effect at
50 mg/t after 72 hours
or at 100 mg/t after
12 days
soft water
6-hour LCso = 160
mg/t In hard water
NC
NC
no observed effect at
100 mg/t after 21 days
NC
temperature = 18*C
hardness =135 mg/t
Reference
Inglls and
Davis, 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Folraar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar, 1977
Mayer and
Filers leek. 1986
-------
TABLE 4-1 (cont.)
Median Response Concentration*
Species
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Leporols macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunftsh
Lepomls macrochlrus
Blueglll sunflsh
Leporols macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomls macrochlrus
Blueglll sunflsh
Lepomts roacrochlrus
Blueflll sunflsh
Leporols macrochlrus
Chemical
Endothall Herbicide 282
(67. 9X liquid concentrate)
Hydrothol 191
(53X liquid concentrate)
potassium salt
(40. 3X liquid concentrate)
Endothall
(17. 5X granular formulation)
Aquathol K
(40. 3X liquid
Aquathol K
(40. W liquid
Aquathol K
(40. 3X liquid
Aquathol K
(40. 3X liquid
Aquathol K
(40. 3X liquid
Aquathol K
(40. 3X liquid
Aquathol K
(40. 3X liquid
Aquathol K
(40. 3X liquid
Aquathol K
(40. 3X liquid
concentrate)
concentrate)
concentrate)
concentrate)
concentrate)
concentrate)
concentrate)
concentrate)
concentrate)
Test
Method
static
static
static
static
static
static
static
static
static
static
static
static
static
24-Hour
1.25 mg/t
1.15 mg/t
>580 mg/t
>10 mg/t
>1000
>1000
>1000
>1000
>1000
>2000
>1000
>2000
mg/t
mg/t
mg/l
mg/t
mg/t
mg/t
mg/t
mg/l
1830 mg/t
(1560-2150)
48-Hour
NR
NR
NR
NR
NR
(867-1320)
NR
(1010-2550)
NR
NR
NR
NR
NR
NR
NR
96-Hour
1.20 mg/t
0.94 mg/t
440 mg/t
NR
1070 mg/t
1600 mg/t
1050 mg/t
(798-1380)
1030 mg/t
(845-1260)
975 mg/t
(773-1230)
1740 mg/t
(1410-2150)
1600 mg/t
(1010-2550)
970 mg/t
(840-1120)
343 mg/t
(308-383)
Comments
temperature =
hardness = 44
temperature =
hardness = 44
temperature =
hardness = 44
temperature =
hardness = 40
temperature =
hardness = 44
pH = 6.5
temperature =
hardness = 44
pH = 7.5
temperature •=
hardness = 44
pH = 8.0
temperature =
hardness = 44
pH <= 8.5
temperature =
hardness = 44
pH = 9.5
temperature =
hardness = 44
temperature =
hardness = 44
temperature =
hardness = 44
temperature =
hardness = 44
24°C
mg/t
24"C
mg/t
24°C
mg/t
22BC
mg/t
12«C
mg/l
12°C
mg/t
12°C
mg/t
12«C
mg/l
12«C
mg/l
7*C
mg/l
12°C
mg/l
17°C
mg/l
22°C
rog/l
Reference
Mayer and
Ellersleck.
Mayer and
Ellersleck.
Mayer and
Ellersleck.
Mayer and
Ellersleck.
Mayer and
Ellersleck,
Mayer and
Ellersleck,
Mayer and
Ellersleck,
Mayer and
Ellersleck,
Mayer and
Ellersleck.
Mayer and
Ellersleck.
Mayer and
Ellersleck.
Mayer and
Ellersleck,
Mayer and
Ellersleck,
1986
1986
1986
1986
1986
1986
1986
1986
1986
1986
1986
1986
1986
-------
TABLE 4-1 (cont.)
0
03
O.
1
— J
1
O
•x.
^k
Median Response Concentration*
Species
Redear sunftsh
Lepomls mlcrolophus
Redear sunflsh
Lepomls mlcrolophus
Redear sunflsh
Lepomls mlcrolophus
Green sunflsh
Lepomls cyanellus
Green sunflsh
Lepomls cyanellus
Redear sunflsh
Lepomls mlcrolophus
Redear sunflsh
Lepomls mlcrolophus
Redear sunflsh
Lepomls mlcrolophus
Redear sunflsh
Lepomls mlcrolophus
Carp
Catfish
Ictalurus punctatus
Catfish
Ictalurus punctatus
Catfish
Ictalurus punctatus
Catfish
Ictalurus punctatus
Catfish
Ictalurus punctatus
Chemical
monoamlne salt
monoamlne salt
monoamlne salt
copper salt
(25* wet table powder)
dlsodlum salt
(granular formulation)
dlamlne salt
dlamlne salt
dlamlne salt
dlsodlum salt
acid
dlsodlum salt
(liquid formulation)
dlsodlum salt
(granular formulation)
endothall
(17. 5X granular formulation)
Hydrothol 191
(53X liquid concentrate)
Aquathol K
(40. 3X liquid concentrate)
Test
Method
static.
unmeasured
static.
unmeasured
static.
unmeasured
static
static
static.
unmeasured
static.
unmeasured
static.
unmeasured
static
NR
static
static
static
static
static
24-Hour
0.81 mg/l
(0.78-0.84)
0.68 mg/l
(0.65-0.72)
0.73 mg/l
(0.69-0.80)
1.63 mg/l
(1.29-2.2)
NR
0.53 mg/l
(0.47-0.60)
0.56 nig/1
(0.52-0.62)
0.56 mg/l
(0.52-0.62)
NR
NR
NR
NR
3.4 mg/l
(2.4-4.7)
2.10 mg/l
>150 mg/l
48 -Hour
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
96 -Hour
NR
NR
NR
1.30 mg/l
(1.00-1.80)
NR
NR
NR
NR
125 mg/l
175 ppm
NR
NR
2.1 mg/l
(1.4-2.9)
0.49 mg/l
>150 mg/l
Comments
temperature = 24*C
hardness = 52.5 mg/l
temperature = 24*C
hardness = 210 mg/l
temperature = 24*C
hardness = 368.4 mg/l
temperature = 18*C
hardness = 44 mg/l
no observed effect at
10 mg/l after 12 days
temperature = 24*C
hardness = 52.5 mg/l
temperature = 24°C
hardness =210 mg/l
temperature = 24*C
hardness = 368.4 mg/l
NC
NC
no observed effect at
100 mg/l after 72 hours
no observed effect at
50 mg/l after 72 hours
temperature = 22*C
hardness = 40 mg/l
temperature = 18*C
hardness = 44 mg/l
temperature 12*C
hardness = 44 mg/l
Reference
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Mayer and
Ellersleck. 1986
Folmar. 1977
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Folmar. 1977
Plmental. 1971
Folmar. 1977
Folmar. 1977
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
-------
TABLE 4-1 (conft.)
0
o>
00
Q.
00
1
04/11/89
Median Response Concentration*
Species
Catfish
Ictalurus punctatus
Yellow bullhead
Ictalurus nebulosus
Black bullhead
Ictalurus melas
Goldfish hybrid
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Chemical
Aqua t hoi K
(40. 3X liquid concentrate)
dlsodlum salt
dt sodium salt
acid
dlamlne salt
dlanlne salt
dlanlne salt
dlanlne salt
dlamlne salt
dlamlne salt
monoamlne salt
monoamlne salt
monoamlne salt
monoamlne salt
monoamlne salt
Test
Method
static
static
static
MR
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
24-Hour
>100 ng/t
NR
NR
NR
0.86 mg/t
(0.76-0.98)
1.00 ng/t
(0.90-1.12)
0.82 ng/t
(0.14-0.91)
1.19 ng/t
(1.10-1.28)
1.17 ng/t
(1.03-1.33)
1.26 ng/t
(1.13-1.40)
0.81 ng/t
(0.74-0.88)
1.39 ng/t
(1.32-1.47)
NR
0.98 ng/t
(0.85-1.13)
NR
48-Hour
NR
NR
NR
NR
0.80 ng/t
(0.73-0.88)
0.86 ng/t
(0.81-0.92)
0.80 rag/l
(0.73-0.88)
0.97 mg/t
(0.87-1.08)
1.03 mg/t
(0.90-1.18)
1.15 mg/t
(1.06-1.25)
0.78 mg/t
(0.68-0.89)
1.23 mg/t
(1.16-1.31)
1.50 mg/t
(1.35-1.66)
0.95 mg/t
(0.85-1.06)
1.38 mg/t
(1.28-1.49)
96-Hour
>100 mg/t
170-175 ng/t
180-185 ng/t
175 ppm
NR
NR
NR
NR
NR
NR
NR
1.20 mg/t
(1.13-1.28)
NR
NR
NR
Comments
temperature = 22"C
hardness = 40 mg/t
NC
NC
NC
temperature ° 24"C
hardness = 52.5 mg/t
temperature = 24°C
hardness = 52.5 mg/t
temperature = 24°C
hardness = 210 mg/t
temperature = 24"C
hardness = 210 mg/t
temperature = 24°C
hardness = 368.4 mg/t
temperature ° 24*C
hardness = 368.4 mg/t
temperature = 24*C
hardness = 52.5 mg/t
temperature = 24°C
hardness = 52.5 rag/t
temperature = 24°C
hardness = 52.5 mg/t
temperature = 24°C
hardness = 210 mg/t
temperature = 24°C
hardness = 210 mg/t
Reference
Mayer and
Ellersteck. 1986
Folmar. 1977
folmar. 1977
Plmental. 1971
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis, 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis, 1973
-------
TABLE 4-1 (cont.)
M
o»
00
Q.
1
hO
1
Median Response Concentration*
Species
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Goldfish
Carasslus auratus
Fathead minnow
Plmephales pronelas
Bluntnose nlnnow
Plmephales notatus
Chemical
nonoamlne salt
nonoamlne salt
monoamtne salt
monoamtne salt
potassium salt
hydrothol 191
(53X liquid concentrate)
dlsodtum salt
Test
Method
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static.
unmeasured
static
static
24 -Hour
1.28 mg/l
(1.20-1.36)
1.17 mg/t
(1.04-1.21)
NR
1.18 mg/l
(1.09-1.28)
NR
1.90 ng/t
NR
48-Hour
1.18 ng/t
(1.11-1.26)
1 .05 ng/t
(0.93-1.18)
1.52 ng/t
(1.38-1.67)
1.14 ng/t
(1.08-1.21)
NR
NR
NR
96-Hour
1.11 ng/t
(1.06-1.16)
NR
NR
1.08 ng/t
(1.02-1.14)
372 ng/t
(340-406)
0.75 ng/t
110-120 mg/t
Comments
temperature = 24*C
hardness =210 ng/t
temperature = 24*C
hardness = 368.4 mg/t
temperature « 24'C
hardness - 368.4 mg/t
temperature = 24*C
hardness = 368.4 mg/t
temperature = 20-23°C
hardness = 50 mg/t
temperature = 18*C
hardness = 44 mg/t
NC
Reference
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Inglls and
Davis. 1973
Berry. 1984
Mayer and
E Her sleek. 1986
Folmar, 1977
Bluntnose minnow
Plraephales notatus
Lake Emerald Shiner
Golden shiner
Notemlgonus crysoleucas
dtsodtum salt
(granular formulation)
cocoamlne salt
nonoamlne salt
(53X active Ingredient)
static
NR
flowthrough.
measured
NR
0.12 ppm
NR
Golden shiner nonoamlne salt
Notemlgonus crysoleucas (53X active Ingredient)
flowthrough. NR
measured
NR
NR
NR
NR
NR
NR
NR
NR
no observed effect at
40 mg/t after 21 days
NC
120-hour LCso °-32
mg/t (0.19-0.46)
hardness = 279 mg/t
120-hour LC50 1.6
mg/t (1.2-2.0)
hardness - 20 mg/t
Folmar. 1977
Ptmental. 1971
Flnlayson. 1980
Flnlayson. 1980
o
^
•^
CO
10
Redfln shiner
Notropls lutrensls
Redfln shiner
Notropls lutrensls
Redslded shiner
Notropls umbratnis
dl sodium salt
dlsodtum salt
(granular formulation)
dtsodtum salt
static
static
static
NR
NR
NR
NR
NR
NR
95 ng/t
NR
105 ng/t
NC
no observed effect at
40 mg/t after 21 days
NC
Folmar.
Folmar.
Folmar.
1977
1977
1977
-------
TABLE 4-1 (cont.)
o
CO
o.
rs»
O
1
04/11/89
Median Response Concentration*
Species
Redslded shiner
Notropls umbratllls
Smallmouth bass
mlcropterus dolomleul
Smallmouth bass
mlcropterus dolomleul
Largemouth bass
Largemouth bass
Hlcropterus salmoldes
Hlcropterus salmoldes
Hlcropterus salmoldes
Hlcropterus salmoldes
Striped bass
Horone saxltllls
Salmon
Coho salmon
Oncorhynchus klsutch
Cutthroat trout
Salmo clarfcl
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo qalrdnerl
Chemical
dlsodlum salt
(granular formulation)
dlsodlum salt
(liquid formulation)
dtsodtum salt
acid
acid
dlsodlum salt
dlsodlum salt
dlsodlum salt
dlsodlum salt
(granular formulation)
dlsodlum salt
(15. 5X a.e.)
acid
Aquathol K
(40. 3X liquid concentrate)
Hydrothol 191
(53X liquid concentrate)
copper salt
dlmethylamtne salt
cocoamlne salt
Test
Method
static
static
static
NR
NR
static
static
static
static
static.
unmeasured
NR
static
static
NR
NR
static
24-Hour
NR
NR
NR
>560 ppm
NR
NR
NR
NR
NR
2000 ppm
(1850-2050)
NR
>100 mg/l
0.18 mg/t
(0.12-0.27)
NR
NR
NR
48-Hour
NR
NR
NR
NR
NR
NR
NR
NR
NR
1700 ppm
(1590-1820)
136 ppm
NR
NR
0.290 ppm
1.15 ppm
1.5 mg/t
96-Hour
NR
NR
NR
NR
120 ppm
NR
200 mg/t
100-125 mg/t
NR
710 ppm
(634-795)
NR
>100 mg/l
0.18 mg/l
(0.12-0.27)
NR
NR
NR
Comments
no observed effect at
40 mg/t after 21 days
no observed effect at
25 mg/t after 12 days
no observed effect at
10 mg/t after 12 days
NC
NC
no observed effect at
10 mg/t after 72 hours
soft water
NC
no observed effect at
10 mg/t after 21 days
temperature = 21 *C
hardness = 35 ppm
NC
temperature = 13*C
hardness = 44 mg/t
temperature » 10*C
hardness = 162 mg/t
NC
NC
NC
Reference
Folmar, 1977
Folmar. 1977
Folmar, 1977
Plmental. 1971
Plmental, 1971
Folmar. 1977
Folmar. 1977
Folmar. 1977
Folmar. 1977
Wellborn. 1971
Plmental. 1971
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
Plmental. 1971
Plmental. 1971
Folmar. 1977
-------
TABLE 4-1 (cont.)
o
& Median Response Concentration*
g Species
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo qalrdnerl
Rainbow trout
Salmo galrdnerl
^ Rainbow trout
i Salmo qalrdnerl
Rainbow trout
Salrap qalrdnerl
Rainbow trout
Salmo qalrdnerl
Harlequin fish
Erlmyzon sucetta
Erlmyzon sucetta
Fowlers Toad
Bufo woodhousel fowlerl
Chemical
dl sodium salt
(granular formulation)
Aquathol K
(40. 3X liquid concentrate)
Aquathol K
(40. 3X liquid concentrate)
copper salt
(25X wet table powder)
endothall
(17. 5X granular formulation)
Endothall DES-I-CATE
(5.5X liquid concentrate)
Endothall Herbicide 282
(67. 9X liquid concentrate)
Hydrothol 191
(53X liquid concentrate)
potassium salt
(40. 3X liquid concentrate)
acid
phlsodlum salt
(liquid formulation)
dlsodlum salt
(granular formulation)
Hydrothol 191
(53X liquid concentrate)
Test
Method
static
static
static
static
static
static
static
static
static
NR
static
static
static
24 -Hour
NR
>420 mg/t
58 mg/t
(49-67)
0.35 mg/t
(0.27-0.45)
2.8 mg/t
(2.3-3.4)
0.50 mg/t
1.15 mg/t
0.81 mg/t
>560 mg/t
565 ppm
NR
NR
3.2 mg/t
(1.7-5.5)
48-Hour
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
96-Hour
NR
230 mg/t
(187-283)
32 mg/t
(22-46)
0.14 mg/t
(0.08-0.24)
1.8 mg/t
(1.2-2.5)
0.31 mg/t
0.98 mg/t
0.56 mg/t
450 mg/t
NR
NR
NR
1.2 mg/l
(0.4-3.4)
Comments
no observed effect at
10 mg/t after 21 days
temperature = 13*C
hardness = 44 mg/t
temperature = 12*C
hardness = 44 mg/t
temperature = 13*C
hardness = 44 mg/t
temperature = 12*C
hardness = 40 mg/t
temperature = 13"C
hardness = 44 mg/t
temperature = 13°C
hardness = 44 m/gt
temperature = 13*C
hardness = 44 mg/t
temperature = 13"C
hardness = 44 mg/t
NC
no observed effect at
25 mg/l after 12 days
no observed effect at
10 mg/t after 12 days
temperature = 15*C
hardness = 44 mg/l
Reference
Folmar. 1977
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck, 1986
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck, 1986
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
Plmetal. 1971
Folmar. 1977
Folmar. 1977
Mayer and
Ellersleck. 1986
2 *Values In parentheses represent 95X confidence Interval
-^
^ NR = Not reported; NC = no comment; a.c. = acid equivalent
-------
TABLE 4-2
Median Response Concentrations for Invertebrates Exposed to Endothall
GO
0.
r\J
ro
i
0
^^
^v
«^n
Median Response Concentration*
Species
Aquatic saw bugs
Asellus conrounls
Scud
Gammarus fasclatus
Scud
Ganmarus fasclatus
Scud
Gamtnarus fasclatus
Scud
Gamrearus lacustrls
Scud
Gammarus lacustrls
Scud
Gamrearus lacustrls
Scud
Gamaarus lacustrls
Scud
Hyallela azteca
Seed shrimp
Cypretta kawatal
Shrimp
Palaemonetes kadlakensts
Midge
Chlronlmus tentans
Chemical
dlpotasslum salt
cocoamlne salt
potassium salt
(40. W liquid
concentrate)
Hydrothol 47
(66. 7X liquid
concentrate)
dlpotasstum salt
endothall
dlsodlum salt
Hydrothol 191
(53X liquid
concentrate)
dlpotasslum salt
monohydrate acid
(99.9X)
Hydrothol 191
(53X liquid
concentrate)
monohydrate acid
(99.9X)
Test Method
flowthrough
flowthrough
static
static
NR
NR
static
static
flowthrough
static
static
static
24 -Hour
NR
3.1 ng/t
313 mg/l
1.50 Bg/t
(0.53-4.2)
>100 ppm
2 ppm
NR
2.00 mg/t
(1.6-2.7)
NR
180 mg/t
(141-230)
>0.10 ng/ft
354 mg/l
(161-780)
48-Hour
NR
2.1 mg/t
NR
NR
NR
NR
NR
NR
NR
NR
NR
NR
96 -Hour
NR
0.48 mg/t
313 mg/t
0.51 ng/t
(0.28-0.95)
NR
NR
>320 ppm
0.5 mg/t
(0.37-0.67)
NR
NR
0.05 mg/t
(0.02-0.12)
NR
Comments
temperature = 17°C
effective concentration
>10 ppm after 120 hours
NC
.temperature = 21 *C
hardness = 44 mg/t
temperature = IS'C
hardness = 272 mg/t
NC
NC
temperature = 59°F
temperature = 21*C
hardness = 272 mg/t
temperature = 17°C
effective concentration
>10 ppm after 120 hours
72-hour ECso =123 mg/t
(89.9-168)
temperature = 21 °C
hardness = 272 mg/t
72-hour ECso = 151
(112-203)
Reference
U1 11 lams
et al., 1984
Folroar. 1977
Mayer and
Ellersleck. 1986
Mayer and
Ellersleck. 1986
Plmental. 1971
Plmental. 1971
Nebeker and
Gaufln. 1964
Mayer and
Ellersleck. 1986
Williams
et al., 1984
Hansen and
Kawatskl. 1976
Mayer and
Ellersleck. 1986
Hansen and
Kawatskl. 1976
-------
TABLE 4-2 (cont.)
0
co Species
n.
Stonefly
Pteronarcys callfornlca
Water flea
Daphnla maqna
Clams
Hercenarla nercenarla
Median Response Concentration*
Chemical
hydrothol 191
(53X liquid
concentrate)
acid
dl sodium salt
Test Method
24-Hour
static 5.75 mg/t
static 46 ppn
(36-57)
static NR
48-Hour
3.25 mg/t
NR
50 mg/l
96-Hour
NR
NR
NR
Comments
temperature = 15*C
hardness = 44 mg/l
26-hour median Immobili-
zation concentration
NC
Reference
Mayer and
I Hers leek. 1986
Crosby and
Tucker. 1966
Folmar. 1977
(eggs)
Clams
Hercenarla mercenarla
(larvae)
Oyster
Crassostrea vlrglnlca
dlsodlm salt
dlsodtum salt
static
static
NR
NR
NR
NR
NR
NR
effective concentration
>10 mg/t after 10 days
effective concentration
>25 mg/t after 12 days
Folmar. 1977
Folmar. 1977
to *Values In parentheses represent 95X confidence Interval
NC «= No comment; NR = not reported
03
vO
-------
Nebeker and Gaufln (1964) generated a 96-hour LC5Q for scud exposed to the
dlsodlum salt of >320 ppm. The 96-hour LC5Q for scud exposed to a mono-
N,N-d1methyl cocoamlne salt formulation was 0.48 mg/l (Folmar, 1977). The
26-hour median Immobilization concentration for Daphnla maqna exposed to the
acid was 46 ppm (Crosby and Tucker, 1966).
Folmar (1976, 1978) assessed the avoidance response of rainbow trout (£.
galrdnerl) fry and mayfly (Ephemerella walkerl) nymphs to the dlpotasslum
salt of endothall. Organisms were placed 1n a flowthrough Y-shaped avoid-
ance maze 15 minutes before the Introduction of endothall; the distribution
of organisms between each arm was recorded after 1 hour. The Investigator
reported that neither trout nor mayflys avoided endothall at the highest
concentration tested (10 mg/a, active Ingredient).
4.1.2. Chronic Effects on Fauna.
4.1.2.1. TOXICITY -- L1gour1 et al. (1983) assessed the effects of
endothall on juvenile Chinook salmon, Onchorynchus tshawytscha. Fish were
exposed to endothall 1n 160-1 glass aquaria that received lake water at a
flow rate of 1 l/mln, resulting 1n a complete turnover of test solution
every 5 hours. Endothall solutions were dripped Into test aquaria from
MaMott flasks at a rate of 1 mi/m1n. Water temperature was maintained at
~16°C. Endothall concentrations were measured on the first and eighth days
of the assays. The Investigators reported a nominal 14-day LC5Q (and 95%
cofldence limits) of 62.5 ppm (53.4-73.1) as the acid equivalent (88.2% ppm
of Aquathol K). Surviving fish exposed to lower concentrations of endothall
demonstrated poor survival when transferred to seawater during a recovery
period. F1sh exposed to >3 ppm endothall for 14 days experienced 80-100%
mortality within 4 days when transferred to seawater. Conversely, fish
transferred to freshwater demonstrated high levels of survival (>80%)
following 14 days of exposure to <55 ppm endothall.
0168d -24- 04/19/89
-------
4.1.2.2. BIOACCUMULATION/BIOCONCENTRATION — S1kka et al. (1975)
monitored the uptake of 14C-endothall by blueglll sunflsh, L. macrochlrus.
F1sh were exposed to 2 ppm 14C-endothall 1n 500 ml of solution for 96
hours, or by force-feeding encapsulated 14C-endothall at a rate of 10 mg
endothall/kg bw. The quantity and distribution of 14C 1n force-fed fish
was determined 48 hours after feeding. The Investigators reported that <1%
of the total amount of herbicide was taken up by fish from water. Fish fed
[14C]endothall eliminated 73% of the administered dose 1n the 48 hours
after feeding. The Investigators found no evidence suggesting that
bluegllls are capable of metabolizing endothall.
Isensee (1976) assessed the bloaccumulatlon potential of endothall In
aquatic model ecosystems. Tests were conducted In glass tanks containing
4 i of water. Before the establishment of test microcosms, soil to be
used as substrate 1n the system was treated with 14C-endothall. The
system was Inoculated with Daphnla magna. snails (Physa). algae (Oedogonlum
cardlacum) and 10 ml of old aquarium water containing a variety of
diatoms, protozoa and rotifers. After 30 days, 2 mosqultoflsh were added to
the tanks and all organisms were harvested 3 days later. BR values were
based on the ratio of 14C In tissue versus that 1n water. The Investi-
gators reported BR values of 63, 36, 150 and 10 for algae, snails, daphnlds
and fish, respectively.
Serns (1977) reported that endothall levels 1n tissues of bluegllls from
a pond treated with 5.0 mg/9. potassium endothall were not detectable
(<0.01 mg/i) 3 days after treatment of the pond, despite water levels of
4.9-3.4 mg/8. from days 3-10 after treatment. Residue levels of 0.02 and
0.04 mg/l were found In fish tissues 2 hours and 1 day, respectively,
after treatment of the pond. Measured concentrations of endothall In the
water column for those time periods were 6.2 and 4.9 mg/i, respectively.
0168d -25- 04/19/89
-------
Relnert and Rodgers (1986) conducted field trials In Texas to validate
models attempting to predict the fate of dlpotasslum endothall In natural
ponds. They also attempted to estimate fish BCFs from caged blueglll
sunflsh, L.. macrochlrus. held 1n ponds treated with 2 mg/a. The Investi-
gators reported a lack of endothall residues 1n tissues of fish held 1n
treated ponds 7 days after the Initiation of treatment. They estimated BCF
values of 0.65-1.05 for fish from regression equations using a water
solubility of 1228 g/i and a log KQW of 0.132.
4.1.3. Effects on Flora.
4.1.3.1. TOXICITY -- Walsh (1972) assessed the effects of the add
and amlne and dlpotasslum salts of endothall on photosynthesis and growth of
four species of marine algae, Chlorococcum sp., Dunallella tertlolecta.
Isochrysls galbana and Phaeodactylum tMcornutum. Effects on photosynthesis
were determined by monitoring oxygen evolution from log phase growth
cultures In the presence of endothall at I0-m1nute Intervals for 90 minutes
on a photosynthesis-model resplrometer. Effects on growth were determined
after 10 days for cultures maintained at 20°C under 6000 lux Illumination
with alternating 12-hour periods of light and dark. EC5Q values were
calculated based on the concentration of the product, although the percent
active Ingredient 1n products used was not specified. The 90-mlnute EC™
values based on photosynthesis for the four algal species exposed to the
technical add were 100, 425, 60 and 75 ppm, respectively. Photosynthetlc
EC,- values for the amlne and dlpotasslum salts for each species were
>1000 and >5000 ppm, respectively for a 90-m1nute treatment period. Growth
EC5Q values for each spedes exposed to the technical add were 50, 50, 25
and 15 ppm, respectively, after 90 minutes of treatment. Growth EC5_
values for species exposed to the amlne salt were 300, 450, 225 and 250 ppm,
0168d -26- 04/11/89
-------
respectively, after 90 minutes. Growth EC50 values for algae exposed to
the dlpotasslum salt were 1500, 1500, 3000 and 500 ppm, respectively, after
90 minutes.
Cain and Cain (1983) assessed the effects of exposure to the amlne salt
of endothall (Hydrothol 191 as N,N-d1methylalkylam1ne salt, 53%) on zygo-
spore germination and growth of the alga, Chlamydomonas moewusll. Exposure
of algal cultures and zygospores to endothall was conducted on 1.5% agar
plates to which endothall had been added. Plates with algal cultures were
Incubated at 21°C for 7 days after Inoculation. Plates with zygospores were
Incubated for 3 days. Cell counts were obtained by first rinsing algae from
the surface of each plate, and then homogenizing suspensions In a micro-
blender and determining absorbance readings for each suspension at 565 nm
with a spectrophotometer. Growth was expressed as a percentage of the
controls. Endothall concentrations were based upon concentration of the
active Ingredient. The Investigators reported I5Q values of 1.7 yM for
growth and 94 yM for zygospore germination. Growth of cultures at the
lowest concentration of endothall tested (1 yM) was significantly
different from the control cultures. The minimum alglcldal concentration
was 7.5 yM as determined by growth and 9.0 yM with respect to zygospore
germination.
4.1.3.2. BIOCONCENTRATION -- Relnert et al. (1988) estimated a water-
milfoil, Myrlophyllum splcatum, BCF for the dlpotasslum salt of endothall
from a regression equation designed for use In situations with constant
exposure conditions for 96-120 hours. The equation was generated from data
collected on an aquatic herbicide, several organic compounds, a floating
aquatic macrophyte and log K . The Investigators estimated a BCF of 0.73
using a log KQW of 0.132. Previously, Relnert et al. (1985) and Relnert
0168d -27- 04/19/89
-------
and Rodgers (1986) reported experimental BCF values of 3.9, 12.1 and 768.9
for dlpotasslum endothall from studies conducted with milfoil 1n 1.1 m
diameter greenhouse pools. The Investigators discounted the 768.9 value as
unrealistic because of the Inadvertent analysis of endothall-tolerant
epiphytic algae present on the milfoil.
4.1.4. Effects on Bacteria. Pertinent data regarding the effects of
exposure of aquatic bacteria to endothall were not located In the available
literature dted 1n Appendix A.
4.2. TERRESTRIAL TOXICOLOGY
4.2.1. Effects on Fauna. Pertinent data regarding the effects of
exposure of terrestrial fauna to endothall were not located In the available
literature cited 1n Appendix A.
4.2.2. Effects on Flora. Pertinent data regarding the effects of
exposure of terrestrial flora to Endothall were not located 1n the available
literature cited In Appendix A.
4.3. FIELD STUDIES
Yeo (1970) assessed the effects of the dlsodlum or dlpotasslum salts of
endothall on aquatic weeds and fish In 13 farm reservoirs and plastic growth
pools (122 cm2x60 cm deep) stocked with common vegetation, smallmouth
bass, green sunflsh and mosqultoflsh. Calculated Initial concentrations
were <3 ppm 1n reservoirs and <4 ppm 1n growth pools. The Investigators
reported that application of endothall to the reservoirs controlled a
variety of pondweeds and other plants but did not affect populations of
elodea, duckweed, nHella and chara. The Investigators did not observe any
mortalities among the smallmouth bass, green sunflsh or mosqultoflsh.
Effects on vegetation In growth pools were similar to those observed 1n
reservoirs. There were no mortalities among bass and sunflsh 1n the growth
0168d -28- 04/11/89
-------
pools; several mosqultoflsh were killed, but the Investigators did not
attribute the mortalities to the endothall treatment of the pools.
Serns (1975) assessed the effects of the dlpotasslum salt of endothall
on the zooplankton community of a 0.31 ha pond 1n Wisconsin. Control and
treatment ponds were drained before treatment to eliminate existing fish
populations, and were then allowed to refill from a common source. Both
ponds were restocked with blueglll sunflsh at a rate of 20 males and 20
females per hectare. Dlpotasslum endothall was added to one of the ponds at
a rate of 5 mg/8. (active Ingredient) at the end of May 1973, and both
ponds were monitored through the end of October 1973. The Investigators
reported the presence of Cladocera (Daphnla. CeModaphnla and Chydorus).
cyclopold and calanold copepods, and ostracods In the treatment pond at
densities equal to or greater than those found 1n the control pond at
various times over the course of the study period. The Investigator
concluded that there no apparent effects on zooplankton communities In the
pond as a result of treatment with dlpotasslum endothall at 5 mg/fi,.
Holmberg and Lee (1976) treated a 0.32 ha pond with 5.0 mg/l (active
Ingredient) endothall. The Investigators monitored effects on vascular
plants and caged and natural populations of blueglll sunflsh, L_. macro-
chlrus. Endothall treatment effectively eliminated coontall, Ceratophyllum
demersum. flat-stemmed pondweed, Potamogeton zosterlformls. sago pondweed,
Potamogeton pectlnatus. milfoil, MyMophyllum splcatum, and elodea, Elodea
canadensls. within 3 weeks of treatment at the recommended dosage. The
treated pond was eventually taken over by chara, Chara sp. There were no
mortalities among either free or caged bluegllls at the endothall treatment
level of 5 mg/8. within a few weeks following treatment.
0168d -29- 04/19/89
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Serns (1977) reported the results of long-term observations of bluegllls
exposed to endothall as part of a continuing study first reported by
Holmberg and Lee (1976). Bluegllls were collected from control and treated
ponds 18 months after the Initial application of 5 mg/a of endothall.
Percent survival of bluegllls stocked 1n the two ponds before treatment was
greater 1n the control pond than 1n the endothall-treated pond, although
growth of adult bluegllls 1n the treated pond was less than that 1n the
control pond. The difference was attributed to competition as a result of
greater density of fish, rather than to a toxic effect from exposure to
endothall. Length, weight, density and standing crop of young-of-year blue-
gills spawned In both ponds during the observation period were equivalent;
there were no perceptible effects on reproduction or survival of first
generation bluegllls.
Beckmann et al. (1984) assessed the effects of the dlpotasslum salt of
endothall on the bacterial populations In gravel-pH ponds over ~4 months.
Parameters measured Included total bacterial numbers In the water column and
respiration rates of bacteria collected from the treated pond. Endothall
was applied to the treatment pond at a target concentration of 0.3 ppm.
Respiration rates were measured 1n the presence of 5 ppm endothall. The
Investigators reported that endothall had no effect on total bacterial
numbers present 1n the control and treated ponds and did not significantly
alter respiration rates of bacteria found 1n those ponds.
4.4. AQUATIC RISK ASSESSMENT
The majority of studies assessing the toxldty of endothall to aquatic
organisms are not suitable for use 1n developing water quality criteria by
the method of U.S. EPA/OWRS (1985). In many Instances, Investigators failed
to Identify the endothall salt present In a formulation Identified only by
0168d -30- 04/24/89
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Us tradename, the percentage of active Ingredient 1n an endothall product,
the "Inert" Ingredients 1n an endothall formulation, or the material upon
which an LC5Q was calculated (formulation or active Ingredient). Criteria
generated by the method of U.S. EPA/OURS (1985) do not permit the use of
data generated on formulated mixtures and emulslflable concentrates.
Apparently, the sodium and potassium salts are often used 1n field
treatments for nuisance aquatic weed control at treament dosages of 2-5
mg/a.. The acute toxlclty of these salts appears to be >100 mg/l,
suggesting a low order of toxlclty under normal use conditions. Addition-
ally, experimental evidence suggests that the sodium and potassium salts of
endothall are not persistent and do not bloaccumulate In aquatic organisms,
thereby reducing the potential for chronic exposure.
4.5. SUMMARY
The potassium and sodium salts of endothall are the forms least toxic to
both aquatic vertebrates and Invertebrates, with 96-hour LC s of >100
mg/i. In contrast, 96-hour LC5Qs for the amlne and copper salts are <1
mg/i for a variety of aquatic organisms. Water hardness did not Influence
the toxlclty of dlsodlum or dlamlne salts to bluegllls (Inglls and Davis,
1973) and pH did not affect the toxlclty of Aquathol K to bluegllls (Mayer
and Ellersleck, 1986). The toxlclty of Aquathol K to blueglll sunflsh
Increased 5-fold when the test temperature Increased from 7 to 24°C (Mayer
and Ellersleck, 1986).
The 14-day LC5Q of endothall to juvenile Chinook salmon, Onchorynchus
tshawytscha. was 62.5 ppm (LlgouM et al., 1983). Surviving fish demon-
strated poor survival when transferred to seawater but good survival when
transferred to freshwater. The 10-day growth EC5Qs for various species of
marine algae exposed to the amlne and dlpotasslum salts ranged from 225-3000
0168d -31- 04/11/89
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ppm (Walsh, 1972). No short- or long-term effects were observed among
natural populations of organisms 1n ponds or reservoirs treated with <5
mg/8, endothall.
Experimental evidence suggests that endothall 1s not likely to bloaccu-
mulate In aquatic organisms. Slkka et al. (1975) reported that bluegllls
took up <1% of the available herbicide from water over a 96-hour period.
Isensee (1976) reported bloaccumulatlon ratios of 63, 36, 150 and 10 for
algae, snails, daphnlds and fish. Serns (1977) was unable to detect
endothall residues 1n tissues of bluegllls from a pond that had been treated
3 days earlier with endothall to give a concentration of 5 mg/l. Relnert
and Rodgers (1986) were unable to detect endothall residues In tissues of
bluegllls from a reservoir that had been treated 7 days earlier with 2
mg/B, endothall. Relnert et al. (1988) reported BCFs of 3.9, 12.1 and
768.9 for the dlpotasslum salt of endothall 1n watermllfoll, but discounted
the highest value because of experimental errors.
0168d -32- 04/19/89
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5. PHARMACOKINETICS
5.1. ABSORPTION
Six adult Wlstar rats weighing 250-260 g (two males) or 172-206 g (four
females) were prefect diets containing unlabeled endothall (5 ppm) for 2
weeks before single gavage administration of 14C-labeled endothall
dissolved 1n 20% ethanol (5 mg/kg) (Soo et al., 1967). As Indicated 1n
Section 5.4., total recovery of radioactivity 1n the feces, urine and
expired CO- at 48 or 72 hours following treatment ranged from 95.7-99.1%
of the administered dose. Most of the radioactivity, 84.8-91.1% of the
administered dose, was excreted 1n the feces, and the balance was excreted
1n the urine (5.7-6.9%) and expired COp. Approximately 20% of the radio-
activity 1n the feces was shown to be unchanged endothall, with the
remainder bound In some unknown form (Section 5.3.). The Investigators
presumed that the remaining radioactivity was due to an endothall conjugate.
However, since bound endothall 1n the feces does not necessarily mean that
the endothall was conjugated, and biliary excretion of endothall appears to
be Insignificant (Section 5.4.), U seems likely that the bound endothall
was unabsorbed endothall that was adsorbed onto gastrointestinal contents.
Low levels of radioactivity 1n tissues other than the stomach and .Intestine
and slow tissue elimination rates also seem to Indicate that only a small
proportion of the administered dose was absorbed (Section 5.2.). Therefore,
results of this study suggest that endothall was poorly absorbed from the
gastrointestinal tract. Intestinal diffusion or secretion of endothall,
however, or conjugation of endothall 1n the Intestines could have occurred.
An additional nine female Wlstar rats were given 1 mg of 14C-endothall
by gavage, and were killed at 1, 2, 4, 6, 8, 12, 24, 48 or 72 hours. Eleven
different organs were removed and freeze-drled, and their radioactivity was
0168d -33- 04/19/89
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measured. Analysis of the specific radioactivity and total accumulation In
each tissue Indicated that only a small proportion of the administered dose
was absorbed. Peak tissue concentrations of radioactivity were found In the
animal that was sacrificed 1 hour after treatment (Section 5.2.). This
Indicates that absorption of endothall occurred largely within the first
hour.
5.2. DISTRIBUTION
Nine female Wlstar rats were given 1 mg of 14C-endothall by gavage and
sacrificed at 1, 2, 4, 6, 8, 12, 24, 48 or 72 hours (Soo et al., 1967).
Peak tissue concentrations of radioactivity were reached In all of 11
tissues sampled except the Intestine within 1 hour posttreatment. The
radioactivity was highest 1n the stomach and Intestine (-98% of the admin-
istered dose). Approximately 1% of the administered dose was found In both
the liver and kidney; trace amounts were found 1n the blood, lung, heart,
spleen, muscle and brain. Radioactivity was not detected 1n body fat,
reflecting the hydrophlUc nature of the compound. Clearance was monophaslc
from the Intestine (half-time of 14.4 hours) and liver (half-time of 21.6
hours), and blphaslc from the stomach (half-times of 2.2 and 14.4 hours) and
kidney (half-times of 1.6 and 34.6 hours). No residual radioactivity was
seen at 72 hours 1n any organ other than the Intestine.
In order to determine the possible secretion of Ingested endothall In
milk, two pregnant female rats were given unlabeled endothall (0.2 mg/day In
10% sucrose) by means of a medicine dropper for the last week of gestation,
and were then given 14C-endothall (0.4 mg/day In 10% sucrose solution) for
5 days after the pups were born. Analysis of stomach contents and tissues
of 12 pups of various ages showed no radioactivity, suggesting that
endothall was not secreted In the milk of a lactatlng female rat.
0168d -34- 04/19/89
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5.3. METABOLISM
Six rats that were administered 5 mg/kg 14C-labeled endothall by
gavage excreted 84.8-91.1% of the administered radioactivity 1n the feces
(Soo et al., 1967) (Section 5.4.). Alcohol extraction and paper chromato-
graphy of the feces showed that "20% of the fecal radioactivity was due to
unchanged endothall and 80% was bound In some form (I.e., unextractable).
The Investigators presumed that the latter radioactivity was due to an
endothall conjugate. As biliary excretion seems to be Insignificant
(Section 5.4.), U 1s likely that the bound endothall was not conjugated,
although conjugation 1n the Intestine could have occurred. Urinary radio-
activity accounted for 5.9-6.9% of the administered dose. The radioactivity
recovered 1n the urine appeared to be unchanged endothall. A small amount
of the administered radioactivity (2.6-2.8%) was converted to CO,, and
expired 1n the breath. Since gastrointestinal absorption of endothall seems
to be poor, It Is possible that the CO- resulted from metabolism by Intes-
tinal microorganisms. There were no apparent gender-related differences 1n
the fate of endothall.
5.4. EXCRETION
A 5 mg/kg dose of 14C-endothall was administered to six rats by gavage
(Soo et al., 1967) (see Section 5.1.). Radioactivity 1n the feces accounted
for 64.5-71.2, 17.7-20.7 and 0.1-0.5% of the administered dose after 24, 48
and 72 hours, respectively. Since levels of radioactivity In the liver were
not very large compared with the administered dose (see Section 5.2.), 1t
was concluded that biliary excretion does not seem to be significant. Dally
recovery of radioactivity 1n the urine accounted for 3.4-6.8, 0.3-0.6 and
0.1-0.2% of the administered dose after 24, 48 and 72 hours, respectively.
0168d -35- 04/19/89
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Less than 3% of the administered dose (2.6-2.8%) was found 1n expired CO-
after 24 hours; radioactivity 1n the expired air was not detected after 48
and 72 hours. Excretion 1n the feces, urine and expired air, therefore,
occurred largely 1n the first 24 hours and was essentially complete after
48-72 hours, as total recovery varied from 95-99%. Endothall was not
excreted 1n the milk (see Section 5.2.).
5.5. SUMMARY
Data obtained from rats of both sexes treated with a single oral dose of
14C-endothall suggest that gastrointestinal absortlon 1s poor (Soo et a!.,
1967). Peak tissue concentrations occurred within 1 hour In all tissues
sampled except the Intestine. The absorbed radioactivity occurred predomi-
nately 1n the stomach and Intestine (~99% of the administered radioactiv-
ity). About 1% of the administered radioactivity occurred 1n the liver and
kidneys. Radioactivity was not found In fat or milk, and was essentially
eliminated from all tissues within 72 hours. At least 85% of the adminis-
tered dose was excreted 1n the feces, but ~20% of this was unchanged com-
pound and 80% was bound In some form. It seems more likely that the bound
form 1s endothall that Is adsorbed onto gastrointestinal contents rather
than an endothall conjugate. Small quantities were excreted 1n the urine
(~6%), apparently as unchanged compound, and 1n the breath as CO- (~3%).
0168d -36- 04/19/89
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6. EFFECTS
6.1. SYSTEMIC TOXICITY
6.1.1. Inhalation Exposure. Pertinent data regarding the effects of
Inhaled endothall were not located 1n the available literature cited 1n
Appendix A.
6.1.2. Oral Exposure.
6.1.2.1. SUBCHRONIC — Rats were given 1000 or 10,000 ppm d1sodium
endothall 1n the diet for 4 weeks (BMeger, 1953a). Using a body weight of
0.4 kg, a dally food consumption of 20 g, and the ratio of the molecular
weight of endothall to dlsodlum endothall, these concentrations can be con-
verted to equivalent doses of endothall 1on of 40 mg/kg/day and 400
mg/kg/day. At the low dose, there were slight liver degeneration and focal
hemorrhaglc areas In the kidney. At the high dose, most of the rats died
within 1 week.
Nine male dogs (one dog per dose) were given capsules containing 1-50 mg
dlsodlum endothall/kg/day (0.8-40 mg/kg/day of endothall 1on) for 6 weeks.
01 sodium endothall doses of >20 mg/kg/day resulted 1n death 1n all dogs
within 11 days, and erosion and hemorrhages of the stomach (Brleger, 1953b).
Congestion of the stomach and edema of the stomach and upper Intestines were
common 1n all dogs. The Investigators suggested that the lesions In the
stomach of dogs resulted from the administration of the undiluted test
substance without food.
6.1.2.2. CHRONIC — Beagle dogs (four/sex/group) were fed 0, 100, 300
or 800 ppm dlsodlum endothall 1n the diet (equivalent to 0, 2, 6 or 16 mg
endothall 1on/kg/day) for 24 months (Keller, 1965; Pennwalt Agchem, n.d.).
Values for hematology, BSP clearance, SGOT, urlnalysls, weight gain and food
consumption 1n treated animals were not significantly different from
0168d -37- 06/19/89
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controls. Relative and absolute stomach and small Intestine weights were
Increased at the two higher doses, but extensive hlstopathologlcal exami-
nation of rats receiving the highest dose revealed no compound-related
lesions, except Increased mucosal gland activity In the stomach and slight
edema In the region of the pylorls. No effects were noted at 2 mg/kg/day.
No toxic effects were noted 1n female rats (strain unspecified) given
<2500 ppm d1 sodium endothall 1n the diet for 2 years (equivalent to 100
mg/kg/day of the endothall 1on assuming food Intake of 20 g/day and mean
body weight of 0.4 kg) (BMeger, 1953b).
6.1.3. Other Relevant Information. A suicide occurred with acute
1ngest1on of -100 mg endothall 1on/kg (Allender, 1983). Repeated vomiting
was consistent with 1ngest1on of an Irritant. The autopsy showed focal
edema and focal hemorrhages In the lungs and gross hemorrhage of the gastro-
intestinal tract.
Male Swiss-Webster mice, weighing 20-25 g (numbers not specified), were
Injected IntraperUoneally with a single dose of 75 mg/kg endothall and 10
mg/kg cantharldlc add (Grazlano and Caslda, 1987). (Cantharldlc acid 1s
similar In structure to endothall and both compounds cause similar signs of
acute toxlclty.) This dose was lethal, usually producing death within 60-90
minutes. Animals that were sacrificed by cervical dislocation after 45
minutes had significantly Increased liver weights (-36%) and hepatic hemo-
globin levels (~100%). Hepatic glycogen metabolism Increased, while hepatic
ATP concentrations decreased. No changes were seen 1n hepatic GSH content,
mlcrosomal I1p1d peroxldatlon, hepatic trlglycerldes or SGPT levels.
An oral (gavage) LD,. for adult Sherman rats was reported to be 57
mg/kg for males and 46 mg/kg for females for the add form (Galnes and
Under, 1986). In another study with rats, the ID™ for orally admin-
istered endothall 1n the add form was 38-51 mg/kg and as the sodium salt
0168d -38- 06/19/89
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was 182-197 mg/kg (Slmslman et al., 1976; Worthing and Walker, 1983). The
Intraperltoneal L05Q for mice was reported to be 14 mg/kg for the add
form (Matsuzawa et al., 1987). An Intravenous Injection of 5 mg/kg d1sodium
endothal 1s fatal to dogs and rabbits (Goldstein, 1952; Srensek and Woodard,
1951).
6.2. CARCINOGENICITY
6.2.1. Inhalation. Pertinent data regarding the cardnogenlclty of
Inhaled endothall were not located 1n the available literature dted 1n
Appendix A.
6.2.2. Oral. No statistically significant Increase 1n number of tumors
was seen In rats fed diets containing 2500 ppm d1 sodium endothall (equiva-
lent to endothall 1on at 100 mg/kg/day) for 2 years (Brleger, 1953b);
however, this study probably did not use contemporary cancer testing
methodology.
6.2.3. Other Relevant Information. Endothall was positive for
transformation In BALB/c 3T3 cells (Litton B1onet1cs, 1981). Pertinent data
regarding the cardnogenlclty of endothall administered by other routes were
not located 1n the available literature dted 1n Appendix A.
6.3. MUTAGENICITY
Endothall was not mutagenlc 1n S. typhlmuMum with or without metabolic
activation (Table 6-1) (Andersen et al., 1972; Remondelll et al., 1986;
Microbiological Associates, 1980b), In Neurospora crassa (Sandier and
Hamllton-Byrd, 1981), and for sister chromatld exchange 1n human lymphocytes
(Vlgfusson, 1981). Mixed results were obtained 1n Drosophlla melanogaster
(WHson et al., 1956; Sandier and Ham1Hon-Byrd, 1981).
6.4. TERATOGENICITY
Pregnant rats (25-26 group) were given oral doses of 0, 10, 20 or 30
mg/kg/day of aqueous endothall technical (0, 8, 16 or 24 mg endothall
0168d -39- 06/19/89
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1ABIF 6-1
Mulagenlclty and Genotoxlcily Summary lable for Endothall
00
o.
Assay
Reverse mutation
Reverse mutation
Reverse mutation
forward mutation
Mutagcnlcity assay
i
g Sister chromatld
i exchange
Point mutation
Sex-linked
recessive lethal
Sex-linked
recessive lethal
Indicator/Organism
Salmonella typhlmurlum
8 mutants
S. typhlmurluro
S. typhlmurlum
TA98. TA100. TA1537.
TA9?. 1A2637
S. typhlmurluro
1A98, 1A100
Neurospora crassa
human lymphocytes
BALB/313 clone A31
mouse cells
Orosophila melanoqaster
D. melanogaster
Purity
technical
technical
technical
technical
?8.6X acid
equivalent
28. 6X acid
equivalent
technical
"commercial"
28.6% acid
equivalent
Application
plate
NR
plate Incorpora-
tion
tube Incubation
NR
cell culture
cell culture
vapor exposure
of adults and
larval feeding
NR
Concentration/Dose
1-5 pi
NR
<5.0 ing/plate
NR
NR
NR
NR
vapor. NR/feeding.
100 and 250 ppm
NR
Activating Response
System
»S9
-
,S9 - 1
fS9 - 1
-
»S9 - 1
-
NR - '
1
NR
none - 1
i
NA * (both vapor 1
and larval)
NA
1
Reference
Andersen el al.,
197?
Microbiological
Associates, 1980a
RemondelII et al.,
1986
Remondel11 et al..
1986
Sandier and
Hamilton-Byrd, 1981
Vigfusson. 1981
Microbiological
Associates, 1980b
Wilson et al.. 1956
Sandier and
Hamllton-Byrd, 1981
*It was unclear whether positive result occurred both with and without metabolic activation.
NR = Not reported; NA = not applicable
CD
CD
-------
1on/kg/day) on gestation days 6-19 (Science Applications, Inc., 1982).
Maternal deaths occurred at the two higher doses, but the fetuses of the
surviving dams exhibited no signs of teratogenldty or fetotoxldty. No
effects were observed on the dams or fetuses at the low dose. A NOAEL of 10
mg endothall technlcal/kg/day (8 mg/kg/day of endothall 1on) was Identified
from this study for teratogenlc effects based on maternal effects.
6.5. OTHER REPRODUCTIVE EFFECTS
Hale and female rats were fed diets containing dlsodlum endothall at 0,
100, 300 or 2500 ppm (equivalent to 0. 4, 12 or 100 mg/kg/day of endothall
1on) until they were 100 days old (Scientific Associates, 1965). They were
mated and the offspring were maintained on the same diet, again for 100
days, when they were mated. The third generation was treated similarly. At
the low dose, there was no effect; at the middle dose level, the pups had
reduced body weights at 21 days of age. At the high dose, the pups died
within 1 week of birth and this dosage was discontinued. A NOAEL for
reproductive effects of 4 mg 1on/kg/day was Identified.
6.6. SUMMARY
Minimal data were located In the available literature regarding the
health effects of endothall. Acute toxlclty appears to be substantially
greater for the add form than for the dlsodlum salt. Oral LD5Q values
for rats of 38-57 mg/kg have been reported for the add form (Worthing and
Walker, 1983; Galnes and Under, 1986) and 182-197 mg/kg have been reported
for the dlsodlum salt. Acute exposure to large doses Is extremely Irritat-
ing and causes erosion and hemorrhage of the stomach (Allender, 1983;
Brleger, 1953b).
Subchronlc data suggest that dogs may be more sensitive than rats to
oral exposure to endothall. In a dietary study, rats succumbed to dosages
0168d -41- 06/19/89
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of the Ion of 400 mg/kg/day and exhibited liver and kidney lesions at 40
mg/kg/day (Brleger, 1953a). Dogs treated by capsule, however, died at 20
mg/kg/day d1sodium endothall (16 mg/kg/day endothall Ion) and had congestion
and edema of the stomach at 0.8 mg/kg/day of endothall Ion (Brleger,
1953b). The Investigators suggested that the lesions 1n the stomach
resulted from the administration of the undiluted test solution without food.
There are notable discrepancies between the subchronlc and chronic data.
For example, no toxic effects were reported 1n a 2-year dietary study where
rats were exposed to 2500 ppm dlsodlum endothall (100 mg/kg bw/day of endo-
thall Ion) (Brleger, 1953b). In a 2-year dietary study using dogs (4/dose),
elevated relative and absolute stomach and small Intestine weights were
Increased with dlsodlum endothall at 300 and 800 ppm (6 and 16 mg/kg/day of
endothall 1on), but no effects were observed at 100 ppm (2 mg/kg/day of the
1on) (Keller, 1965; Penwalt Agchem, n.d.).
Developmental toxlclty studies using rats suggest that the dams are more
susceptible than the fetuses to oral administration of endothall (Science
Applications, Inc., 1982). In a dietary study, pregnant rats were given 0,
8, 16 or 24 mg endothall 1 on/kg/day on gestation days 6-19. Maternal deaths
occurred at the two higher doses but the fetuses of the surviving dams
exhibited no signs of teratogenlclty or fetotoxldty. A NOAEL of 8
mg/kg/day was Identified from this study for teratogenlclty based on
maternal effects.
In a 3-generatlon reproductive study, no effects were observed when rats
were exposed to dlsodlum endothall 1n the diet that provided a dosage of
endothall 1on at 4 mg/kg/day (Scientific Associates, 1965). In the same
3-generat1on study, however, pups In the 12 mg/kg/day group had reduced body
weights and pups In 100 mg/kg/day group died within a week of birth.
0168d -42- 06/19/89
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Endothall has not been adequately tested for carclnogenldty. There was
no evidence of cardnogenlcHy In rats fed diets containing dlsodlum endo-
thall at <2500 ppm (100 mg/kg/day of the 1on) for 2 years 1n an early study
(Brleger, 1953b). Endothall Induced malignant transformation of BALB/c 3T3
cells (Utton B1onet1cs, Inc., 1981). Endothall was not mutagenk 1n
microorganisms (Andersen et al., 1972; RemondelH et al., 1986;
Microbiological Associates, 1980a; Sandier and Ham1lton-Byrd, 1981) and In
human lymphocytes (Vlgfusson, 1981). Mixed results were obtained 1n
Drosophla (Wilson et al., 1956; Sandier and Ham1lton-Byrd, 1981).
0168d -43- 06/19/89
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7. EXISTING GUIDELINES
7.1. HUMAN
The verified IRIS oral RfD 1s 0.02 mg/kg/day (U.S. EPA, 1986d), based on
a NOEL for gastrointestinal effects In dogs In a 2-year feeding study
(Pennwalt Agchem, n.d.; Keller, 1965).
U.S. EPA (1987a) derived a Lifetime Health Advisory of 0.14 mg/l based
on the ADI set by U.S. EPA Office of Pesticide Programs of 0.02 mg/kg/day.
The 1- and 10-day HAs for a 10 kg child are 0.8 mg/l based on a NOAEL of 8
mg/kg/day for the absence of fetal and maternal effects 1n rats exposed to
endothall acid orally for 13 days (Science Applications, 1982). The DUEL 1s
0.7 mg/l based on the 2-year study using dogs (Keller, 1965). Endothall
1s Included In a 11st of 83 chemicals required to be regulated by the Agency
under a 1986 amendment of the Safe Drinking Water Act (U.S. EPA, 1987b).
An Interim tolerance of 0.2 ppm has been established for Its residues 1n
potable water resulting from use of endothall salts to control aquatic
plants (U.S. EPA, 1987c). Tolerances In raw agricultural commodities are
0.1 ppm 1n cottonseed and potatoes and 0.05 ppm 1n rice grain and rice straw
(U.S. EPA, 1982). The RQ 1s 1000 (U. S. EPA, 1985).
7.2. AQUATIC
Guidelines and standards for the protection of aquatic life from
exposure to endothall were not located In the available literature cited In
Appendix A.
0168d -44- 06/19/89
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8. RISK ASSESSMENT
Statements concerning available literature 1n this document refer to
published, quotable sources and are 1n no way meant to Imply that confiden-
tial business Information (CBI), which this document could not address, do
not exist. From examination of the bibliographies of the CBI data, however,
1t was determined that CBI data that would alter the approach to risk
assessment or the risk assessment values presented herein do not exist.
8.1. CARCINOGENICITY
8.1.1. Inhalation. No data were available to assess the carcinogenic
potential of endothall by the Inhalation route.
8.1.2. Oral. Rats fed <100 mg 1on/kg/day for 2 years had no significant
Increase 1n number of tumors (Brleger, 1953b).
8.1.3. Other Routes. No data were available to assess the carcinogenic
potential of endothall from other routes.
8.1.4. Weight of Evidence. No data were available regarding the carclno-
genldty of endothall In humans. Rats fed <100 mg lon/kg/day for 2 years
had no significant Increase In number of tumors (Brleger, 1953b), but the
adequacy of this study as a cancer bloassay cannot be evaluated because of
the lack of the primary report. Also, H 1s likely that this early study
did not use contemporary cancer testing methodology. The animal data are
Insufficient. Therefore, endothall Is assigned to EPA Group D, not classi-
fiable as to human cardnogenlclty (U.S. EPA, 1986a). This 1s consistent
with the classification assigned by the Agency 1n an earlier evaluation
(U.S. EPA, 1987a).
8.1.5. Quantitative Risk Estimates. No q^* can be derived because
endothall 1s assigned to EPA Group D.
0168d -45- 04/19/89
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8,2. SYSTEMIC TOXICITY
8.2.1. Inhalation Exposure. No data were available to assess the
systemic toxldty of endothall from Inhalation.
8.2.2. Oral Exposure.
8.2.2.1. LESS THAN LIFETIME EXPOSURE (SUBCHRONIC) — Subchronlc oral
data consist of a 4-week study using rats and a 6-week study using dogs.
These studies were available only as very brief reviews by U.S. EPA (1987a)
of the Confidential Business Information (CBI) studies from the Office of
Pesticides Program files. In the rat study, dietary dlsodlum endothall
provided dosages of endothall 1on of 40 or 400 mg/kg/day (BHeger, 1953a).
Most rats at 400 mg/kg/day died within 1 week; liver degeneration and hemor-
rhaglc areas 1n the kidneys were reported at 40 mg/kg/day. Dogs treated
with dlsodlum endothall 1n capsules died and had erosions and hemorrhage 1n
the stomach at doses >20 mg/kg/day (16 mg/kg/day of the 1on) (Brleger,
1953b). Stomach lesions were observed at 1 mg/kg/day dlsodlum endothall,
the lowest dose tested. The Investigators suggested that the lesions 1n the
stomachs of dogs at very low dosages resulted from the administration of the
undiluted test material without food (U.S. EPA, 19866). These data suggest
that dogs are more sensitive than rats to endothall, but are Insufficient
for derivation of an RfD for subchronlc oral exposure. The chronic oral RfD
of 0.02 mg/kg/day (Section 8.2.2.2.) 1s adopted as the subchronlc oral RfD.
Confidence In the key study Is medium (U.S. EPA, 1986d), which 1s apparently
due 1n part to the limited number of animals per dose and the limited range
of doses. Confidence 1n the data base and RfD also are medium (U.S. EPA,
1986d).
0168d -46- 06/19/89
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8.2.2.2. CHRONIC EXPOSURES — Chronic data for endothall are limited
to two 2-year CBI studies using rats and dogs. Brleger (1953b) reported no
effects In rats fed a diet containing dlsodlum endothall at 2500 ppm (100
mg/kg bw/day of endothall 1on). In dogs fed dlsodlum endothall 1n the diet
at 0, 100, 300 or 800 ppm (dosages of endothall 1on of 0, 2, 6 or 16
mg/kg/day), elevated stomach weights were observed at >300 ppm, but no
effects were observed at 100 ppm (2 mg/kg/day) (Keller, 1965; Pennwalt
Agchem, n.d.). U.S. EPA (1986d, 1987a) derived an RfD for endothall of 0.02
mg/kg/day by applying an uncertainty factor of 100 (10 for Interspedes
differences, 10 for Intraspedes differences) to the dog NOEL of 2 mg/kg/
day. Stomach lesions were observed 1n dogs treated with 0.8 mg endothall
lon/kg/day by capsule for 6 weeks (Brleger, 1953b). Although lower than the
2 mg/kg day NOEL, this LOAEL Is an Inappropriate basis for an RfD because of
the bolus method of treatment (capsule without food), which does not repre-
sent environmental exposure. However, unprotected endothall applicators or
members of the general population near application sites could swallow low
doses of endothall following dust exposure (I.e., by mucodllary clearance).
The RfD of 0.02 mg/kg/day, which Is verified and available on IRIS (U.S.
EPA, 1986d), therefore, Is adopted as the RfD for chronic exposure to
endothall for the purposes of this document. Confidence 1n the key study,
data base and RfD are medium (U.S. EPA, 1986d).
0168d -47- 06/19/89
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9. REPORTABLE QUANTITIES
9.1. BASED ON SYSTEMIC TOXICITY
The systemic toxldty of endothall was discussed In Chapter 6. Data
from these studies relevant for derivation of CSs are summarized In Table
9-1. In the 24-month study using dogs, slight edema and Increased mucosal
gland activity were observed at a dosage of 16 mg/kg/day endothall 1on;
Increased absolute and relative weights of the stomach and small Intestine
were reported at 6 mg/kg/day (Keller, 1965; Pennwalt Agchem, n.d.). Conges-
tion and edema of the stomach and edema of the upper Intestines at 1 mg
dlsodlum endothall/kg/day and death at 20 mg/kg/day reported In a 6-week dog
study by BMeger (1953b) 1s not Included In Table 9-1 because undiluted
compound had been administered In capsules not accompanied by food, a
protocol not relevant to environmental exposure. Death observed In rats at
10,000 ppm dlsodlum endothall 1n the diet and the liver and kidney lesions
at 1000 ppm In the diet In the 4-week rat study by BMeger (1953a) are not
Included because the study duration was too short.
Composite scores for the effects presented 1n Table 9-1 are calculated
1n Table 9-2. The CS of 7.6 for Increased relative and absolute weight of
stomach and small Intestine In dogs (Keller, 1965; Pennwalt Agchem, n.d.},
equivalent to an RQ of 1000, Is chosen to represent the chronic toxldty of
endothall (Table 9-3).
9.2. BASED ON CARCINOGENICITY
Cancer data for endothall (see Section 6.2.) consist of the statement
that rats fed diets containing 2500 ppm dlsodlum endothall for 2 years (100
mg endothall 1on/kg/clay) had no significant Increase In tumor Incidence, but
the adequacy of this study cannot be evaluated. Endothall Is assigned to
EPA Group D. Because hazard ranking 1s not possible for Group D compounds,
a cancer-based RQ cannot be assigned to endothall.
0168d -48- 04/19/89
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cr
oo
TABLE 9-1
Toxlclty Summary for Oral Exposure to Endothall Using the Beagle Doga»b
No. /Sex Exposure
Transformed
Animal Dosec
(mg/kg/day)
Equivalent
Human Dosed
(mg/kg/day)
Response
4/sex
4/sex
800 ppm dlsodium
endothall In diet
for 24 months
300 ppm dlsodium endothall
In diet for 24 months
16
9.1
3.4
Slight edema and In-
creased mucosal gland
activity In stomach
Increased absolute
and relative weights
of stomach and small
Intestine
aSource: Keller, 1965; Pennwalt Agehem, n.d.
Reference body weight for dogs = 12.7 kg (U.S. EPA, 1986c)
Expressed as endothall Ion
dThe transformed animal dose Is multiplied by the cube root of the ratio of the animal body weight to
reference human body weight (70 kg).
o
-f*
CO
to
-------
TABLE 9-2
Composite Scores for Endothall Ion Using the Doga
Animal Dose
(mg/kg/day)
Chronic
Human MEOb
(mg/day)
RVd Effect
RVe CS RQ
16
637 1.3 Slight edema and In-
creased mucosal gland
activity In stomach
238 1.9 Increased absolute
and relative weight
of stomach and small
Intestine
5 6.5 1000
4 7.6 1000
aSource: Keller, 1965; Pennwalt Agchem, n.d.
Equivalent human dose multiplied by 7,0 kg to express MED as mg/day for a
70 kg human
0168d
-50-
04/19/89
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TABLE 9-3
ENOOTHALL
Minimum Effective Dose (MED) and Reportable Quantity (RQ)
Route:
Dose*:
Effect:
RVd:
RVe:
Composite Score:
RQ:
Reference:
oral
238 tug/day
Increased stomach and small Intestine weights
1.9
4
7.6
1000
Keller 1965; Pennwalt Agchem, n.d.
*Equ1valent human dose
0168d
-51-
04/19/89
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0168d -63- 04/19/89
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APPENDIX A
LITERATURE SEARCHED
This HEED Is based on data Identified by computerized literature
searches of the following:
CHEMLINE
TSCATS
CASR online (U.S. EPA Chemical Activities Status Report)
TOXLINE
TOXLIT
TOXLIT 65
RTECS
OHM TADS
STORET
SRC Environmental Fate Data Bases
SANSS
AQUIRE
TSCAPP
NTIS
Federal Register
CAS ONLINE (Chemistry and Aquatic)
HSDB
SCISEARCH
Federal Research In Progress
These searches were conducted In Hay, 1988, and the following secondary
sources were reviewed:
ACGIH (American Conference of Governmental Industrial Hyglenlsts).
1986. Documentation of the Threshold Limit Values and Biological
Exposure Indices, 5th ed. Cincinnati, OH.
ACGIH (American Conference of Governmental Industrial Hyglenlsts).
1987. TLVs: Threshold Limit Values for Chemical Substances 1n the
Work Environment adopted by ACGIH with Intended Changes for
1987-1988. Cincinnati, OH. 114 p.
Clayton, G.D. and F.E. Clayton, Ed. 1981. Patty's Industrial
Hygiene and Toxicology, 3rd rev. ed., Vol. 2A. John Wiley and
Sons, NY. 2878 p.
Clayton, G.D. and F.E. Clayton, Ed. 1981. Patty's Industrial
Hygiene and Toxicology, 3rd rev. ed., Vol. 2B. John Wiley and
Sons, NY. p. 2879-3816.
0168d -64- 04/19/89
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Clayton, G.D. and F.E. Clayton, Ed. 1982. Patty's Industrial
Hygiene and Toxicology, 3rd rev. ed., Vol. 2C. John Wiley and
Sons, NY. p. 3817-5112.
Grayson, M. and D. Eckroth, Ed. 1978-1984. Klrk-Othmer Encyclo-
pedia of Chemical Technology, 3rd ed. John Wiley and Sons, NY. 23
Volumes.
Hamilton, A. and H.L. Hardy. 1974. Industrial Toxicology, 3rd ed.
Publishing Sciences Group, Inc., Littleton, MA. 575 p.
IARC (International Agency for Research on Cancer). IARC Mono-
graphs on the Evaluation of Carcinogenic Risk of Chemicals to
Humans. IARC, WHO, Lyons, France.
Jaber, H.M., W.R. Mabey, A.T. Lieu, T.W. Chou and H.L. Johnson.
1984. Data acquisition for environmental transport and fate
screening for compounds of Interest to the Office of Solid Waste.
EPA 600/6-84-010. NTIS PB84-243906. SRI International, Menlo
Park, CA.
NTP (National Toxicology Program). 1987. Toxicology Research and
Testing Program. Chemicals on Standard Protocol. Management
Status.
Ouellette, R.P. and J.A. King. 1977. Chemical Week Pesticide
Register. McGraw-Hill Book Co., NY.
Sax, I.N. 1984. Dangerous Properties of Industrial Materials, 6th
ed. Van Nostrand Relnhold Co., NY.
SRI (Stanford Research Institute). 1987. Directory of Chemical
Producers. Menlo Park, CA.
U.S. EPA. 1986. Report on Status Report In the Special Review
Program, Registration Standards Program and the Data Call 1n
Programs. Registration Standards and the Data Call 1n Programs.
Office of Pesticide Programs, Washington, DC.
USITC (U.S. International Trade Commission). 1986. Synthetic
Organic Chemicals. U.S. Production and Sales, 1985, USITC Publ.
1892, Washington, DC.
Verschueren, K. 1983. Handbook of Environmental Data on Organic
Chemicals, 2nd ed. Van Nostrand Relnhold Co., NY.
Wlndholz, M., Ed. 1983. The Merck Index, 10th ed. Merck and Co.,
Inc., Rahway, NJ.
Worthing, C.R. and S.B. Walker, Ed. 1983. The Pesticide Manual.
British Crop Protection Council. 695 p.
0168d -65- 04/19/89
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In addition, approximately 30 compendia of aquatic toxldty data were
reviewed, Including the following:
Battelle's Columbus Laboratories. 1971. Mater Quality Criteria
Data Book. Volume 3. Effects of Chemicals on Aquatic Life.
Selected Data from the Literature through 1968. Prepared for the
U.S. EPA under Contract No. 68-01-0007. Washington, DC.
Johnson, W.W. and M.T. Flnley. 1980. Handbook of Acute ToxUHy
of Chemicals to Fish and Aquatic Invertebrates. Summaries of
Toxldty Tests Conducted at Columbia National Fisheries Research
Laboratory. 1965-1978. U.S. Dept. Interior, Fish and Wildlife
Serv. Res. Publ. 137, Washington, DC.
HcKee, J.E. and H.W. Wolf. 1963. Water Quality Criteria, 2nd ed.
Prepared for the Resources Agency of California, State Water
Quality Control Board. Publ. No. 3-A.
Plmental, D. 1971. Ecological Effects of Pesticides on Non-Target
Species. Prepared for the U.S. EPA, Washington, DC. PB-269605.
Schneider, B.A. 1979. Toxicology Handbook. Mammalian and Aquatic
Data. Book 1: Toxicology Data. Office of Pesticide Programs, U.S.
EPA, Washington, DC. EPA 540/9-79-003. NTIS PB 80-196876.
0168d -66- 04/19/89
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APPENDIX B
Summary Table for Endothall
er
co
O.
Species
Inhalation Exposure
Subchronlc ID
Chronic ID
Cardnogenlclty ID
Oral Exposure
i
T' Subchronlc dog
Chronic dog
Cardnogenlclty ID
REPORTABLE QUANTITIES
Based on Chronic Toxlclty:
o
vD
a Based on Cardnogenlclty:
IO
Exposure Effect RfD or q-j*
ID ID ID
ID ID ID
ID ID ID
100 ppm dl sodium endothall NOEL for 0.02
In the diet for 2 years stomach effects mg/kg/day
(2 mg endothall 1 on/kg/day)
100 ppm dl sodium endothall NOEL for 0.02
In the diet for 2 years stomach effects mg/kg/day
(2 mg endothall lon/kg/day)
ID ID ID
1000
ID
Reference
ID
ID
ID
Keller, 1965;
Pennwalt
Agchem, n.d.
Keller. 1965;
Pennwalt
Agchem, n.d.
ID
Keller, 1965;
Pennwalt
Agchem, n.d.
NA
ID = Insufficient data; NA = not applicable
-------
APPENDIX C
DOSE/DURATION RESPONSE GRAPH FOR EXPOSURE TO ENDOTHALL
C.I. DISCUSSION
A dose/duration-response graph for oral exposure to endothall generated
by the method of Crockett et al. (1985) using the computer software by
Durkln and Meylan (1988) under contract to ECAO-C1nc1nnat1 1s presented In
Figure C-l. Data used to generate this graph are presented 1n Section C.2.
In the generation of this figure, all responses are classified as adverse
(FEL, AEL or LOAEL) or nonadverse (NOEL or NOAEL) for plotting. For oral
exposure the ordlnate expresses dosage as human equivalent dose. The animal
dosage 1n mg/kg/day Is multiplied by the cube root of the ratio of the
animal:human body weight to adjust for species differences In basal meta-
bolic rate (Mantel and Schnelderman, 1975). The result 1s then multiplied
by 70 kg, the reference human body weight, to express the human equivalent
dose as mg/day for a 70 kg human.
The boundary for adverse effects (solid line) Is drawn by Identifying
the lowest adverse effect dose or concentration at the shortest duration of
exposure at which an adverse effect occurred. From this point an Infinite
line Is extended upward parallel to the dose axis. The starting point Is
then connected to the lowest adverse effect dose or concentration at the
next longer duration of exposure that has an adverse effect dose or concen-
tration equal to or lower than the previous one. This process 1s continued
to the lowest adverse effect dose or concentration. From this point a line
1s extended to the right, parallel to the duration axis. The region of
adverse effects lies above the adverse effects boundary.
Using the envelope method, the boundary for no adverse effects (dashed
line) 1s drawn by Identifying the highest no adverse effects dose or concen-
tration. From this point a line parallel to the duration axis 1s extended
0168d -68- 04/19/89
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n
1C
E
v
W
tfi
C
Ci
=
9
Z
C
10000
1000 • r
10
r^
e.00001
(Oral Exposure)
.x.
4-
q-
8.0881 8.881 0.01 0.1
HUMAN EQUIU DURATION (fPact ion lifespan)
ENVELOP METHOD
-M
1 2
Key: F - PEL
L - LOAEL
N - NOEL
Solid line - Adverse Effects Boundary
Dashed line - No Adverse Effects Boundary
FIGURE C-l
Dose/Duration - Response Graph for Oral Exposure to Endothall
Envelope Method
0168d
-69-
04/19/89
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to the dose or concentration axis. The starting point Is then connected to
the next lower or equal no adverse effect dose or concentration at a longer
duration of exposure. When this process can no longer be continued, a line
Is dropped parallel to the dose or concentration axis to the duration axis.
The region of no adverse effects lies below the no adverse effects boundary.
At both ends of the graph between the adverse effects and no adverse effects
/
boundaries are regions of ambiguity. The area (1f any) resulting from
Intersection of the adverse effects and no adverse effects boundaries 1s
defined as the region of contradiction.
In the censored data method, all no adverse effect points located 1n the
region of contradiction are dropped from consideration and the no adverse
effect boundary Is redrawn so that 1t does not Intersect the adverse effects
boundary and no region of contradiction Is generated. This method results
1n the most conservative definition of the no adverse effects region.
Figure C-l presents the dose/duration-response graph generated by the
envelope method. The adverse effects boundary Is defined by a lethal dose
In humans (Allender, 1983, Rec. #8), a LD,Q value In rats (Slmslman et
al., 1976; Worthing and Walker 1983, Rec. #11), and a LOAEL for gastrointes-
tinal effects In dogs administered a capsule providing 0.8 mg/kg/day for 2
years (Brleger, 1953b, Rec. #7). The no adverse effects boundary 1s defined
by a NOEL for rats In a 2-year diet study (Brleger, 1953b, Rec. #3). As
Indicated In Figure C-l, almost all of the points for this chemical fall
within the region of contradiction. This Is attributable to the LOAEL (Rec.
#7) and NOEL (Rec. #3) described above, which appear to be- outliers. The
LOAEL 1s based on a study of low confidence that used a bolus method of
treatment, and the NOEL 1s based on a study of Indeterminate confidence
using a species that may not be the most sensitive. The LOAEL was not used
0168d -70- 04/19/89
-------
as the basis for an RfD because the method of treatment was Inappropriate
(Section 8.2.2.2.). If the LOAEL Is considered to be an outlier, then the
NOEL that serves as the basis for the RfD for subchronlc and chronic oral
exposure (Keller, 1965; Pennwalt Agchem, n.d., Rec. #1) will not occur
within the region of contradiction. Insufficient data are available
(because of the outlying points) to redraw the graph by the censored data
,i
method to eliminate the region of contradiction.
C.2 DATA USED TO GENERATE DOSE/DURATION-RESPONSE GRAPHS
Oral Exposure
Chemical Name:
CAS Number:
Document Title:
Document Number:
Document Date:
Document Type:
Endothall
145-73-3
Health and Environmental Effects Document on Endothall
SRC-TR-88-172
8-30-88
HEED
RECORD #1: Species: Dogs
Sex: Both
Effect: LOAEL
Route: Food
Number Exposed:
Number Responses:
Type of Effect:
SHe of Effect:
Severity Effect:
8
NR
WGTIN
COLON
4
Dose: 6.000
Duration Exposure: 24.0 months
Duration Observation: 24.0 months
Comment:
Citation:
Administered as d1sodium salt. 2, 6 or 16 mg 1on/kg.
Increased stomach and small Intestine weight at 6 and 16,
slight pylork edema at 16. No effect on SGOT, BSP clearance,
hematol, urlnalysls or other hlsto.
Keller, 1965; Pennwalt Agchem, n.d.
0168d
-71-
04/19/89
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RECORD #2:
Comment:
Citation:
Species:
Sex:
Effect:
Route:
Dogs
Both
NOEL
Food
Dose: 2.000
Duration Exposure: 24.0 months
Duration Observation: 24.0 months
Number Exposed: 8
Number Responses: NR
Type of Effect: WGTIN
Site of Effect: COLON
Severity Effect: 4
See previous record. Relative and absolute stomach and7 small
Intestine weights were not Increased.
Keller, 1965; Pennwalt Agchem, n.d.
RECORD #3:
Species:
Sex:
Effect:
Route:
Rats
Female
NOEL
Food
Dose:
Duration
Duration
Exposure:
Observation:
100.000
2.0 years
2.0 years
Comment:
Comment:
Citation:
Number Exposed:
Number Responses:
Type of Effect:
Site of Effect:
Severity Effect:
NR
Administered as dlsodlum salt. Doses were 100 mg 1 on/kg/day
and lower (NOS). No toxic effects noted but endpolnts
examined were not specified. Study summarized In ODW Health
Advisory.
Citation:
RECORD #4:
Brleger,
Species:
Sex:
Effect:
Route:
)953b
Rats
NR
FEL
Food
Dose:
Duration
Duration
Exposure:
Observation:
400.000
4.0 weeks
4.0 weeks
Number Exposed: NR
Number Responses: NR
Type of Effect: MORTL
Site of Effect: BODY
Severity Effect: 10
Administered as dlsodlum salt. Doses were 40 and 400 mg Ion/
kg/day. Most rats died within 1 week. Not specified 1f liver
or kidney effects occurred. Study summarized 1n ODW Health
Advisory.
Brleger, 1953a
0168d
-72-
04/19/89
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RECORD #5:
Comment:
Citation:
Species:
Sex:
Effect:
Route:
Rats
NR
LOAEL
Food
Number Exposed: NR
Number Responses: NR
Type of Effect: OEGEN
SHe of Effect: LIVER
Severity Effect: 6
Dose:
Duration Exposure:
Duration Observation:
NR
NR
HEMOR
KIDNY
6
40.000
4.0 weeks
4.0 weeks
See previous record. Slight liver degeneration and focal
hemorrhaglc areas In the kidneys.
BMeger, 1953a
RECORD #6:
Species:
Sex:
Effect:
Route:
Dogs
Hale
PEL
Capsul
Dose:
Duration
Duration
Exposure:
Observation:
20.000
11.0 days
11.0 days
Comment:
Citation:
Number Exposed: 1
Number Responses: 1
Type of Effect: DEATH
SHe of Effect: BODY
Severity Effect: 10
Administered as dlsodlum salt. Doses: 0.8-40 mg 1on/kg/day
(1 dog/dose). Death 1n all dogs within 11 days at >20.
Stomach erosion and hemorrhage at dosage >20 mg 1on/kg/day.
Study summarized 1n ODW Health Advisory.
BMeger, 1953b
RECORD #7:
Species:
Sex:
Effect:
Route:
Dogs
Hale
LOAEL
Capsul
Dose:
Duration
Duration
Exposure:
Observation:
0.800
6.0 weeks
6.0 weeks
Comment:
Citation:
Number Exposed: 1
Number Responses: 1
Type of Effect: HYPRT
SHe of Effect: COLON
Severity Effect: 3
See previous record. Stomach congestion, edema of stomach and
upper Intestine common 1n all dogs. Additional Information
not reported.
BMeger, 1953b
0168d
-73-
04/19/89
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RECORD #8:
Comment:
Citation:
Species:
Sex:
Effect:
Route:
Humans
Hale
PEL
Oral (NOS)
Dose: 100.000
Duration Exposure: 1.0 days
Duration Observation: 1.0 days
Number Exposed: 1
Number Responses: 1
Type of Effect: DEATH
SHe of Effect: BODY
Severity Effect: 10
/
Suicide due to 1ngest1on of estimated 7-8 g of dlsodlum salt
(-100 mg Ion/kg). Repeated vomiting. Focal edema and
extensive hemorrhages 1n the lungs and gastrointestinal tract
Al lender, 1983
RECORD #9:
Species:
Sex:
Effect:
Route:
Rats
Male
PEL
Gavage
Dose:
Duration
Duration
Exposure:
Observation:
57.000
1.0 days
14.0 days
Comment:
Citation:
Number Exposed: NR
Number Responses: NR
Type of Effect: DEATH
Site of Effect: BODY
Severity Effect: 10
1059. Peanut oil vehicle. Rats observed 14 days or until
recovery. Minimum 10 rats/dose and 4 doses; design of assay
with endothall not specifically reported.
Galnes and Under, 1986
RECORD #10:
Species:
Sex:
Effect:
Route:
Rats
Female
PEL
Gavage
Dose:
Duration
Duration
Exposure:
Observation:
46.000
1.0 days
14.0 days
Comment:
Citation:
Number Exposed: NR
Number Responses: NR
Type of Effect: DEATH
Site of Effect: BODY
Severity Effect: 10
1059. See previous record.
Galnes and Under, 1986
0168d
-74-
04/19/89
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RECORD #11
Comment:
Citation:
Species:
Sex:
Effect:
Route:
Rats
NR
PEL
Oral (NOS)
Dose: 38.000
Duration Exposure: 1.0 days
Duration Observation: 2.0 days
Number Exposed: NR
Number Responses: NR
Type of Effect: DEATH
SHe of Effect: BODY
Severity Effect: 10
LD5Q reportedly 38-51 mg add/kg In 48 hours. Additional
Information not reported. Primary source not available.
.Slmslman et al., 1976; Worthing and Walker, 1983
RECORD #12: Species: Rats
Sex: Femal
Effect: PEL
Route: Oral
*
Number Exposed:
Number Responses
Type of Effect:
SHe of Effect:
Severity Effect:
e
(NOS)
25
: 2
DEATH
BODY
10
Dose: 16.000
Duration Exposure: 14.0 days
Duration Observation: 14.0 days
Comment:
Citation:
Treated on gestation days 6-19. Doses: 8, 16, 24 mg/kg/day.
25-26/group. 10 maternal deaths at 24 mg/kg/day. 2 maternal
deaths at 16 mg/kg/day. No fetal developmental/toxic effects
1n surviving dams; exam day not reported. Prom ODW HA.
Science Applications, Inc., 1982
RECORD #13: Species: Rats
Sex: Femal
Effect: NOEL
Route: Oral
Number Exposed:
Number Responses
Type of Effect:
SHe of Effect:
Severity Effect:
e
(NOS)
25
: 0
DEATH
BODY
10
Dose:
Duration Exposure:
Duration Observation:
NR
NR
TERAD . .
FETUS
8.000
14.0 days
14.0 days
Comment:
Citation:
See previous record.
fetotoxlc effects.
No maternal deaths. No teratogenlc or
Science Applications, Inc., 1982
0168d
-75-
04/19/89
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RECORD #14:
Comment:
Species:
Sex:
Effect:
Route:
Rats
Both
PEL
Food
Dose:
Duration Exposure:
Duration Observation:
100.000
128.0 days
128.0 days
Citation:
Number Exposed: NR
Number Responses: NR
Type of Effect: REPRO
Site of Effect: OTHER
Severity Effect: 10
/
Administered as d1sodium salt. Doses: 4, 12, 100 mg Ion/kg/
day. 100 days of treatment prior to mating. Pups died within
1 week of birth and treatment discontinued. Other Indices not
reported.
Scientific Associates, 1965
RECORD #15:
Species:
Sex:
Effect:
Route:
Rats
Both
LOAEL
Food
Dose:
Duration
Duration
Exposure:
Observation:
12.000
128.0 days
142.0 days
Comment:
Citation:
Number Exposed: NR
Number Responses: NR
Type of Effect: REPRO
SHe of Effect: OTHER
Severity Effect: 4
See previous record. Three generation study; each generation
treated for 100 days prior to mating. Reduced body weights In
pups at 21 days of age. No effect on survival. Other Indices
not reported.
Scientific Associates, 1965
0168d
-76-
04/19/89
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RECORD #16:
Comment:
Citation:
Species:
Sex:
Effect:
Route:
Rats
Both
NOEL
Food
Dose:
Duration Exposure:
Duration Observation:
4.000
128.0 days
142.0 days
Number Exposed: NR
Number Responses: NR
Type of Effect: REPRO
SHe of Effect: OTHER
Severity Effect: 4
See previous record. No effect on survival or body weight of
pups. NOEL for reproductive effects but other Indices not
reported. Study summarized In ODW Health Advisory.
Scientific Associates, 1965
NR = Not reported
0168d
-77-
04/19/89
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
29 !9R°
SUBJECT:
FROM:
TO:
Health and Environmental Effects Document for
Endothall
William H. Farland, Ph.D.
Director
Office of Health and Environmental
Assessment (RD-689)
Matthew Straus
Chief, Waste Characterization Branch
Office of Solid Waste (OS-330)
I am forwarding copies of the Health and Environmental
Effects Document (HEED) for Endothall.
The HEEDs support listings under RCRA, as well as provide
health-related limits and goals for emergency and remedial
actions under CERCLA. These documents represent scientific
summaries of the pertinent available data on the environmental
fate and mammalian and aquatic toxicity of each chemical at an
extramural effort of about $10K. The attached document has been
reviewed within OHEA, by staff in OPP and OTS, and by two
external scientists. „- '
Should you wish to see any of the files related tor the
development of the HEEDs, please call Chris DeRosa at
FTS: 684-7531.
Attachment
«iov }
aiKMAMg)
DATE )
8FA F«M 1
3204 02^0)
CONCUMINC
cs
OFFICU
U. FILE COPY
------- |