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ADVISORY
METOLACHLOR
Criteria and Standards Division
Office of Water Regulations and Standard
United States
Environmental Protection F^gency
MRRCH 1 9 8 G
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WATER QUALITY ADVISORY
Number 6 .
METOLACHLOR
Criteria and Standards Division
Office of Water Regulations and Standards
United States Environmental Protection Agency
c The advisory concentration for Metolachlor in ambient water for
x"'j the protection of freshwater aquatic life is estimated to be 100
^ ug/L. No saltwater data were reviewed for this advisory, and no
advisory concentration for the protection of saltwater aquatic
organisms is estimated. Care should be taken in the application of
*./ this advisory, with consideration of its derivation, as stated in
V the attached support document.
A value given to protect aquatic life can be derived from no
observed effect levels (NOEL), the lowest concentration found in the
data which has been observed to cause acute or chronic toxicity or
t other experimental data which may be applicable. When there is no
* valid experimental evidence, a value may be derived from a model which
uses structure-activity relationships (SAR) as its basis. The advisory
concentrations should be used with caution, since they are derived
from minimal experimental evidence, or in the case of SAR derived
values, no data on the specific chemical.
The advisory concentration for Metolachlor in ambient water for
the protection of human health is estimated to be 44 ug/L, based on
data and information which are available to U.S. EPA. Care should be
taken in the application of this advisory, with consideration of its
derivation, as stated in the attached support document.
An advisory concentration can be derived from a number of sources:
The Office of Drinking Water Health Effects Advisories; Acceptable
Daily Intake(ADI) values from EPA; Office of Pesticides and Toxic
Substances risk assessments; Carcinogen Assessment Group(CAG) cancer
risk estimates; risk estimates derived from the open literature; or
other sources which will be given in the support document. The
advisory concentrations derived from these sources will vary in
confidence and usefulness, based on the amount and quality of data
used as well as the assumptions behind the original estimates. The
user is advised to read the background information carefully to
determine the strengths or deficiencies of the values given in the
advisory.
U S Environmental Prelection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevarjd, 12th Floor
Chicago, IL 60604-3590
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HUMAN HEALTH AND AQUATIC LIFE
LITERATURE SEARCH AND DATA
BASE EVALUATION FOR
METOLACHLOR
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF WATER REGULATIONS AND STANDARDS
CRITERIA AND STANDARDS DIVISION
Washington, D.C. 20460
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TABLE OF CONTENTS
INTRODUCTION 1
SCOPE OF SEARCH 2
SUMMARY OF FINDINGS 2
Aquatic Toxicity 2
Health Effects 7
CRITERIA EVALUATION AND RECOMMENDATION 11
Aquatic Life 11
Health Effects 15
REFERENCES 17
LIST OF TABLES
Table 1. Summary of Aquatic Toxicity Literature Review
of Metolachlor 3
Table 2. Summary of Health Effects Literature Review
of Metolachlor 8
Table3. Values Used to Calculate the Final Value 12
Table 4. Data Requirements for Calculation of Aquatic Life
Interim Criteria--Metolachlor 14
Table 5. Data Requirements for Calculation of Human Health
Interim Criteria Metolachlor 16
LIST OF FIGURES
Figure 1. Summary of Toxicity Data for Metolachlor
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HUMAN HEALTH AND AQUATIC LIFE
LITERATURE SEARCH AND DATA
BASE EVALUATION FOR
METOLACHLOR
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF WATER REGULATIONS AND STANDARDS
CRITERIA AND STANDARDS DIVISION
Washington, D.C. 20460
INTRODUCTION
Metolachlor [2-chloro-N-(2 ethyl-6-methylphenyl)-N-(2-methoxy-l-
methylethyl)acetamide] is a selective herbicide used to control annual
grass weeds, yellow nutsedge, and certain broadleaf species in corn
production. Corps which are sufficiently tolerant to metolachlor are
soybeans, peanuts, potatoes, and certain vegetables (WSSA, 1979).
Metolachlor is manufactured under the name Dual and is packaged in 6
and 8 Ib/gallon emulsifiable concentrates. Metolachlor is also
manufactured under the trade names of Bicep , Primagram , Primextra ,
CGA-24705, Codal and Milocep when it is combined with other herbicides
such as propazine and atrazine which increase the spectrum of its
effectiveness. It was developed by Ciba-Giegy in Basle, Switzerland,
and patented in 1973 and 1976 (EPA, 1980).
Metalachlor is a white to tan liquid at room temperature with the
following physical properties: (EPA, 1980)
Boiling point: 100 °C
Vapor pressure: 10~5 min Hg at 20 °C
Stability: half-life of a 0.25 percent aqueous
solution at 1OO °C is 30 hours at pH3, 18
hours at pH7, and 1.5 hours at pH 10
Specific gravity: 1.085 + 0.005 at 20 °C
Solubility in water: 530 ppm at 20 °C.
Metolachlor belongs to a category of herbicides known as chloro-
acetamides which inhibit growth and reduce cell division and enlarge-
ment. Metolachlor is a soil-applied herbicide and its particular mode
of action is inhibition of root elongation (Ashton and Crafts, 1981).
It is usually applied on or incorporated into the soil at a rate of
1.5-3.0 Ib active ingredient per acre during or soon after planting
but before sprouts emerge (EPA, 1980). Metolachlor has been shown to
be resistant to hydrolysis and rapid metabolism in soil. It also has
the tendency to leach extensively in low-organic soils (EPA, 1980).
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The most significant toxicity of metolachlor to nontarget species
has been with aquatic organisms, particularly fish (Buccafusco, 1978;
Sachsse and Ullman, 1974). Consequently, present concerns focus on
releases of metolachlor into aquatic environments. Research needs
include the identification of quantities of metolachlor which could
reach aquatic systems unchanged by leaching or runoff from farm fields
and the resultant effects of metolachlor on those aquatic systems.
SCOPE OF SEARCH
Sources were identified through a computerized literature search
of TOXLINE, the Toxicological Data Base, TOXBACK, and NTIS files and
through manual bibliographical searches of the available literature.
The computerized literatures searches included published literature
from 1965 to the present. Most of the sources cited in this document
were listed in an EPA (1980) document, Metolachlor-Pesticide Registra-
tion Standard, which cited sources that were not published in the open
literature but were evaluated by the EPA for validity. The search
focused on controlled dose-response studies.
When available, information was obtained on the quality
assurance/quality control (QA/QC) measures employed in the laboratory
and field studies, specifically their use of controls, replicate
treatments, and chemical analysis of test concentrations. Information
also was sought on the bioaccumulation/biomagnification of metolachlor
and other food chain, ecological, and health effects.
Studies were evaluated with respect to guidelines established by
the U.S. EPA in "Guidelines and Methodology Used in Preparation of
Health Effect Assessment Chapters of the Consent Decree Water Quality
Criteria Documents" (FR 45:79347, Nov. 28, 1980), and the "Guidelines
for Deriving Numerical National Water Quality Criteria for the
Protection of Aquatic Life and Their Uses (Stephan et al., 1985). The
search was not intended to be exhaustive, however it was intended to
be thorough in its coverage of accessible, relevant data sources
required for meaningful criteria development.
SUMMARY OF FINDINGS
Aquatic Toxicity
Most of the aquatic toxicity data were taken from a registration
document for metolachlor (Table 1). The numbers presented in the
document were from studies which were not published in journals or
government reports, but were reviewed by EPA prior to acceptance of
the chemical for registration. Although the orginal reports of the
studies were not available, it was assumed that EPA required
acceptable QA/QC measures.
According to the registration document (EPA, 1980), there are no
data available on the toxicity of metolachlor to freshwater algae or
aquatic plant species. However, Ellgehausen et al. (1980) present
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data on the bioaccumulation of metolachlor in aquatic organisms
including the alga Scenedesmus acutus. In order to establish exposure
concentrations for the bioaccumulation study, they determined a no-
effect-level of 0.1 ppm for this species after an unspecified period
of exposure. Other details on the acute toxicity study were not
provided.
The only acceptable study (lethal concentration for 50 percent of
test organisms) on the toxicity of metolachlor to invertebrates
(Figure 1) was a 48-hour LC50 of 25.1 ppm (Vilkas, 1976, as cited in
EPA, 1980). The EPA determined that results from this test were
adequate to characterize the toxicity of metolachlor to invertebrates.
Ellgehausen et al. (1980) determined a no-effect-level for Daphnia
magna of 0.1 ppm; however, no QA/QC measures other than concentration
measurement were reported. Toxicity data on other species of
invertebrates were not available.
Most of the toxicity data on fish species were from the EPA
registration document (EPA, 1980). The EPA approved studies genera-
ting LC50 data for bluegill sunfish (10.0 ppm) and rainbow trout (3.9
ppm). Acute studies exposing fathead minnows, crucian carp, channel
catfish, as well as a flow-through test exposing fathead minnows were
judged inadequate by the EPA (EPA, 1980). In a separate study,
Ellgehausen et al. (1980) determined a no-effect-level for catfish,
Ictalurus me].as, of 0.1 ppm after 96 hours of exposure. Again, there
was no report of quality assurance measures other than concentration
measurement.
A chronic test of the effects of 97.4 percent metolachlor on
reproduction of the fathead minnow reported a maximum acceptable
toxicant concentration (MATC) between 0.78 and 1.60 ppm (Dionne, 1978,
as cited in EPA, 1980). When the fish were exposed to concentrations
higher than the MATC, significantly fewer first and second generation
fry survived.
Metolachlor was reported to accumulate in algae, Daphnia and fish
tissues after exposure times ranging from 90 minutes for algae to 96
hours for catfish (Ellgehausen et al., 1977 and 1980). However, the
concentrations were significantly reduced after depuration periods in
all three cases. The primary source of the accumulated metolachlor
was water, rather than contaminated food organisms. In accumulation
studies of 30-70 days of exposure using catfish (Smith, 1977) and
bluegills (Barrows, 1974), metolachlor accumulated in the fish during
the exposure period and dropped to significantly lower levels after
depuration. A bioaccumulation factor was not calculated in any of the
studies because metolachlor was rapidly metabolized.
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Health Effects
Many studies have been conducted on the health effects of
metolachlor (Table 2), but the studies were not published in open
literature. The data evaluated in this section were taken from
studies cited in the pesticide registration document for metolachlor
(EPA, 1980).
Mammalian acute toxicity studies have shown the LDSOs for
metolachlor to range from 0.3->10,000 mg/kg depending on the route of
exposure (oral, dermal) and the species of test animal (rat, rabbit)
(EPA, 1980). These values also are representative of the toxicity
data from tests of the emulsif iable concentrates of 6 or 8 Ib
metolachlor/gal. Toxicity studies on beagle dogs showed an "emetic
dose" of 19.0 mg/kg. This level was not sufficiently toxic to
establish an acute LC50 (AMRI, 1974b).
Draise tests conducted on rabbits using both technical grade
metolachlor and the 8 Ib/gal emulsifiable concentrate produced
moderate but reversible irritation and corneal opacity in the eyes.
The 6 Ib/gal emulsifiable concentrate, however, produced an
irreversible corneal opacity in the rabbit eye. Because the amount of
active ingredient in the 6 Ib/gal emulsifiable concentrate is less
than that in the 8 Ib/gal, it is likely that the irritation was due to
the inert ingredients of the emulsifiable concentrate rather than to
metolachlor. Another acute effect of technical grade metolachlor was
a positive skin sensitization reaction when applied through
intradermal injection in guinea pigs (Sachsse, 1977).
Metolachlor apparently does not accumulate in mammals because it
is rapidly absorbed and metabolized. Studies have shown ingested
metolachlor to be completely metabolized in rats, goats, and poultry
with no unchanged metolachlor detected in the urine or feces (Hambock,
1974). The metabolic pathway of metolachlor is not yet understood
(EPA, 1980).
A chronic feeding study exposing dogs to metolachlor over a 6-
month period reported a no-observed-effect-level (NOEL) of 100 ppm
(EPA, 1980). Another chronic study showed metolachlor to produce no
oncogenic effects in mice at a level of 3000 ppm (IBT, 1975). Kennedy
(1976) performed a 2-year feeding study on rats which showed no
oncogenic effects. However, the integrity of the rat study was
questioned by EPA because of protocol deficiencies and lack of
concentration verification. The study was redone and the results
indicate the possibility of neoplasm formation at high (3000 ppm)
doses. OPP considers the study to be core minimum, and have
tentatively set the non-neoplastic NOEL at 30 ppm. Tests on the
mutagenicity and fetotoxicity of metolachlor have also produced nega-
tive results (Arni and Miller, 1976; Ciba Geigy Ltd., 1976; Fritz,
1976) .
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CRITERIA EVALUATION AND RECOMMENDATION
Aquatic Life
While the data base required to derive criterion lacks approxi-
mately half of the information needed according to the guidelines
specified in Stephan, et al (1985), sufficient data were found to
calculate an advisory concentration.
An Aquatic Life Criterion consists of a Criterion Maximum Concen-
tration (CMC) and a Criterion Continuous Concentration (CCC).
The CMC is equal to one-half the Final Acute Value (FAV). An
estimated Final Acute Value was calculated using the following
equations.
Final Acute Value = eA
where:
A = S( 0.05) + L
L (In GMAV - S( ( p))/4)
S2 = ((In GMAV)2) - (( (In GMAV))2/4)
cp} _ ( ( ( p) ) 2 /^^
GMAV = Genus Mean Acute Value (the geometric mean of the
species mean acute values for the genus)
P = Cumulative probability as R/N+1
R = Rank from "1" for the
lowest to "N" for the highest GMAV.
The Genus Mean Acute Values (GMAVs) were obtained from the
reviewed literature (Table 1). The values used in calculating the
estimated FAV are presented in Table 3. There are as mentioned above,
insufficient data to calculate a criterion, but the incomplete data
base can be used in calculating an advisory.
Substituting values from Table 3 into the formulae gave an
estimated Final Acute Value of 0.77 ppm.
An estimated maximum concentration for metolachlor was calcu-
lated according to the following:
Maximum concentration = Final Acute Value
0.77 = 0.39 ppm.
2
11
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The estimated Final Chronic Value is equal to the estimated FAV
divided by the Final Acute-Chronic Ratio. Data for calculating an
Acute-Chronic Ratio were available only for fathead minnows (Table 1):
9.2 ppm =7.96
1.17 ppm
The ratio is based on an acute 96-hr LC50 from a fathead minnow test
and the geometric mean of the Maximum Acceptable Toxicant
Concentration (EPA, 1980).
The estimated advisory concentration was calculated by the
following:
Advisory concentration = Final Acute Value
Final Acute-Chronic Ratio
= 0.77 ppm =0.10 ppm.
7.9
Because there currently are no acceptable data on plants, a Final
Plant Value cannot be calculated. Similarly, a Final Residue Value
cannot be calculated because data on either FDA levels in fish or
long-term wildlife acceptable daily intake have not been located.
While there is bioaccumulation information available, as was previous-
ly mentioned, none of the studies allows determination of a bioaccumu-
lation factor. Therefore, the estimated advisory concentration is
equal to 0.10 ppm because it is the only chronic value calculated.
Because these estimates were derived from a partial data base they
cannot be rigorously applied, but should be used as guidance in inter-
preting levels of metholachlor in environmental samples.
These estimates were derived from an acceptable, yet partial, data
base. The acceptability of many of the test results was assumed. The
estimates could be improved with expansion of the data base. The
estimates provided here are not rigorous in their derivation but can
be used to provide guidance in the interpretation of concentrations of
metolachlor found in environmental samples.
The data set for calculating a criterion is currently lacking the
following elements (Table 4): LCSOs for a benthic crustacean, an
aquatic insect species, a phylum other than Arthropoda or Chordata,
and another insect family; acute/chronic data on an invertebrate and
another freshwater species; acceptable test results with a freshwater
algae or an aquatic vascular plant.
13
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TABLE 4. DATA REQUIREMENTS FOR CALCULATION OF AQUATIC LIFE
INTERIM CRITERIAMETOLACHLOR
Available Data
Criterion Requirements
Aquatic Toxicity
Acute test results from tests on:
a. A salmonid (class Osteichthyes) YES
b. A warm water species commercially YES
or recreationally important
(class Osteichthyes)
c. Another family in the phylum YES
Chordata (fish, amphibian, etc.)
d. A planktonic crustacean YES
(cladoceran, copepod, etc.)
e. Benthic crustacean (ostracod, NO
isopod, scud, crayfish, etc.)
f. Insect (mayfly, dragonfly, NO
damselfly, stonefly, mosquito, etc.)
g. Phylum other than Arthropoda/ NO
Chordata (Rotifera, Annelida,
Mollusca)
h. Another family of insect NO
Acute-chronic ratios with species from
three different families:
a. One fish YES
b. One invertebrate NO
c. Acutely sensitive freshwater animal NO
species
Acceptable test results from a test with:
a. Freshwater algae NO
b. A vascular plant NO
Bioaccumulation factor with a freshwater NO
species (if a maximum permissible tissue
concentration is available)
Acceptability of
Available Data
YES
EPA approved
YES
EPA approved
YES
EPA approved
YES
EPA approved
YES
EPA approved
14
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Health Effects
Standards exist for tolerance limits of metolachlor residues in
raw agricultural commodities (40 CFR 180.368). These levels range
from 0.02 ppm to 3.0 ppm in fruits, vegetables, and livestock.
A no-observed-effect-level (NOEL) of 100 ppm has been determined
based on a 6-month dog feeding study (U.S. EPA, 1980).
According to the methods outlined in "Guidelines and Methodology
Used in Preparation of Health Effects Assessment Chapters of the
Consent Decree Water Quality Criteria Documents," ideally a NOAEL,
LOEL, or LOAEL would be used to derive an ADI. However, only the NOEL
for metolachlor is available. The Office of Pesticide Programs calcu-
lated an ADI using the NOEL (U.S. EPA, 1980). A safety factor of 2000
is applied to the NOEL because there are no long-term or acute data on
humans and few studies on experimental animals with no indication of
carcinogenicity (EPA, 1980; Federal Register. 1980) (Table 5). Using
the data from the dog study, a dietary exposure of 100 ppm parts food
is equivalent to a NOEL of 2.5 mg/kg/day. Applying the safety factor
of 2000 and the average adult human weight (70 kg), instead of 60 kg
used by OPP, the ADI is calculated as follows:
ADI = (2.5 mg/kg/day)(70 kg) = 0.088 mg/day.
2000
The ADI is then divided by 2 I/day (average adult human water consump-
tion) to arrive at an interim advisory concentration of 0.044 mg/L.
This value does not reflect consumption of fish contaminated with
metolachlor, but given the low bioconcentration estimate due to rapid
depuration and metabolism, the advisory is expected to be protective
in the event of consumption of contaminated organisms.
This estimate is based on a study approved by the EPA. All other
data used in derivation of the criteria are from unpublished studies
whose QA/QC measures are unknown. The estimate, therefore, should not
be considered firm, but rather as an interim value to provide guidance
until more data become available.
15
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TABLE 5. DATA REQUIREMENTS FOR CALCULATION OF HUMAN HEALTH
INTERIM CRITERIAMETOLACHLOR
Criterion Requirements Acceptability
Human Health Effects Available Data Of Available Data
NonThreshold:
Carcinogen YES ?
Tumor.incidence tests (Incidence Noncarcinogenic
of tumor formation significantly
more than the control for at
least one dose level), or
Data set which can be used to NA*
estimate carcinogenic risk, or
Lifetime average exposure tests, or NA
Human epidemiology studies NA
(if available, not required)
Threshold:
Noncarcinogens YES YES
EPA approved
No observed adverse effect level NO** **
(at least 90-day), or
Lowest observed effect level NO
Lowest observed adverse effect level NO
Acceptable Daily Intake: YES YES
Daily water consumption YES EPA Approved
Daily fish consumption YES EPA Approved
Bioconcentration factor NO
Nonfish dietary intake NO
Daily intake by inhalation NO
Threshold Limit Value: NO
(Based on 8-hour time-weighted
average concentrations in air)
Inhalation Studies: NO
Available pharmacokinetic data
Measurements of absorption efficiency
Comparative excretion data
* Not applicable.
? - Results equivocal.
** NOEL available (EPA approved).
16
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REFERENCES
Ashton, F. M., and A. S. Crafts, 1981. Mode of action of herbicides.
Wiley Interscience Publication. New York, 525 pp.
Code of Federal Regulations, 1984. Metolachlor: tolerances for
residues on raw agricultural commodities. 180.368.
Ellgehausen, H., J. A. Guth, H. 0. Esser, 1980. Factors determining
the bioaccumulation potential of pesticides in the individual
compartments of aquatic food chains. Ecotoxic and Environ. Safety,
4:134-157.
Environmental Protection Agency, 1980. Metolachlor: pesticide
registration standard. EPA/SPRD-80/520, National Technical
Information Service, Springfield, Virginia. 183 pp.
Federal Register, 1982. Tolerances and exemptions from tolerances for
pesticide chemicals in or on raw agricultural commodities:
metolachlor. FR 47:10536; 23932.
Federal Register, 1980. Guidelines and methodology used in prepara-
tion of health effect assessment chapters of the consent decree water
quality criteria documents. FR 45:79347.
Stephan, C. E., D. I. Mount, D. J. Hansen, J. H. Gentile, G. A.
Chapman, W. A. Brungs, 1985. Guidelines for deriving numerical
national water quality criteria for the protection of aquatic
organisms and their uses. U.S. Environmental Protection Agency,
Office of Research and Development, Environmental Research
Laboratories, Duluth, Minnesota.
Weed Science Society of America (WSSA), 1979. Herbicide handbook.
Weed Science Society of America, Champaign, Illinois, pp. 274-279.
REFERENCES AS CITED IN EPA, 1980 METOLACHLOR; PESTICIDE
REGISTRATION STANDARDS
Affiliated Medical Research, Incorporated, 1974a. Acute dermal LD50
of CGA-24705-technical in rabbits: Contract No. 120-2255-34.
Received September 26, 1974 under 5G1553. (Unpublished study prepared
for Ciba-Geigy Corp., Greensboro, NC; CDL: 112840-E.)
Affiliated Medical Research, Incorporated, 1974b. Emetic dose 50 in
beagle dogs with CGA-24705-technical: Contract No. 120-2255-34.
Received September 26, 1974, Greensboro, NC; CDL: 112840-C.
Affiliated Medical Research, Incorporated, 1974c. Twenty-one day
repeated dermal toxicity of CGA-24705-6E in rabbits: Contract No.
120-2255-34. Received September 26, 1974 under 56/553. (Unpublished
study prepared for Ciba-Geigy Corp., Greensboro, NC; CDL: 112840-Q.)
17
-------
Affiliated Medical Research, Incorporated, 1974d. Evaluation of CGA-
24705 technical (FL 740408) as a potential skin sensitizer in the
guinea pig: Contract No. 120-2255-34. Receved September 26, 1974
under 5G1553. (Unpublished report prepared for Ciba-Geigy, Corp.,
Greensboro, NC; CDL: 112840-K.)
Affiliated Medical Research, Incorporated (1974e). Acute inhalation
study of CGA-24705-6E for albino rats: Contract No. 121-2253-34.
Unpublished study received September 26, 1974 under 5G 1533; prepared
for Ciba-Geigy Corp., Greensboro, NC; CDL: 112840-M.
Ami, P., and D. Miller, 1976. Salmonella/mammalian-microsome
mutagenicity test with CGA 24705 (test for mutagenic properties in
bacteria): PH 2.632. Received January 19, 1977 under 7F1913.
(Unpublished study prepared by Ciba-Geigy, Ltd., Basle, Switzerland;
CDL: 95768-B.)
Barrows, M. E., 1974. Exposure of Fish to 14C-CGA-24705.
Accumulation distribution, and elimination of 14C residues. Report
No. 73019-3. (Unpublished study received March 27, 1975 under 5F1606;
prepared by EG&G, Bionomics Environmental Consultants for Ciba-Geigy
Corporation, Greensboro, NC; CDL: 94376-E.)
Bathe, R., 1973. Acute oral LD50 of technical CGA-24705 in the rat:
Project No. Siss 2979. Received September 26, 1974 under 5G1553.
(Unpublished study prepared by Ciba-Geigy Corp., Ltd., Basle,
Switzerland; CDL: 112840-A.)
Buccafusco, R. J., 1978a. Acute toxicity test results of CGA-24705 to
bluegill sunfish (Lepomis macrochirus). Report No. BW-78-181.
Received July 13, 1978 under 100.597. (Unpublished study prepared by
EG&G, Bionomics.)
Buccafusco, R. J., 1978b. Acute toxicity test results of CGA-24705 to
rainbow trout (SaJmo gairdneri). Report No. BW-78-6-186. Received
July 13, 1978 under 100-597. (Unpublished study prepared by EG&G
Bionomics; submitted by Ciba-Geigy Corp., Greensboro, NC., CDL:
234396.)
Ciba-Geigy, Limited, 1976. Reproduction study CGA 24705 Tech.: Rat:
Seg. II. (test for teratogenic or embryotoxic effects). PH 2.632.
Received January 18, 1978 under 7F913. (Unpublished study including
Addendum; CDL: 96717-A; 96717-B.)
Dionne, E., 1978. Chronic toxicity of CGA-24705 to the fathead minnow
(Pimephales promelas); Received December 13, 1978 under 100-587.
(Prepared by EG&G Bionomics for Ciba-Geigy Corporation, Greensboro,
NC; CDL: 236620.)
Ellgehausen, H., 1977. Project Report 3/77: Uptake, transfer, and
degradation of CGA 24705 (Dual.) by aquatic organisms. AC 2.52.
Received February 6, 1978 under 100-583. (Unpublished study prepared
by Ciba-Geigy Ltd., Basle, Switzerland; CDL: 232789-C.)
18
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Fink, R., 1974. Eight-day dietary LC50 - bobwhite quail technical
CGA-24705: Project No. 108-111. Received September 26, 1974 under
5G1553. (Unpublished study by Truslow Farm, Inc., for Ciba-Geigy
Corp., Greensboro, NC; CDL: 112840-P.)
Fink, R., 1976. Acute oral LD5Q- mallard duck: CGA-24705 technical:
Final report. Received November 23, ;976 under 100-587. (Unpublished
study prepared by Truslow Farm, Inc., for Ciba-Geigy Corp.,
Greensboro, NC; CDL: 226955-D.)
Fritz, H., 1976. Reproduction study CGA 24705 Tech. Rat: Seg. II:
(test for teratogenic or embryotoxic effects): PH 2.632. Received
January 19, 1977 under 7F1913. (Unpublished study prepared by Ciba-
Geigy Ltd., Basle, Switzerland; CDL: 95768-A.)
Hambock, H., 1974. Project Report No. 1/74: Distributions,
degradation, and excretion of CGA 24 705 in the rat: AC 2.52.
Received November 25, 1975 under 5G1553. (Unpublished report prepared
by Ciba-Geigy Ltd., Basle, Switzerland; CDL: 94217-K.)
Industrial Bio-Test Laboratories, Inc., 1975. Report to Ciba-Geigy
Corporation: acute dust inhalation toxicity study with CGA-24705 and
CGA-18762 (1:1) 15G (FL-751873) in albino rats: IBT No. 663-07826.
(Unpublished study received February 9, 1976 under 100-EUP-44;
prepared for Ciba-Geigy Corporation, Greensboro, NC; CDL: 96495-B.)
Kennedy, G. L., 1976. Letter (dated December 13, 1976. relative to
the 2-year carcinogencity study of CGA 24705 in albino mice (IBT No.
8531-07925) | to George Rolofson. (Unpublished study received January
19, 1977 under 7F1913; prepared by Industrial Bio-Test Laboratories,
Inc., for Ciba-Geigy Corp., Greensboro, NC; CDL: 94221-C.)
Nham, D., and W. A. Harrison, 1977. Report to Ciba-Geigy Corporation:
Acute oral toxicity study with Dual. 8E in albino rats: IBT No. 8530-
10822. study received November 8, 1977 under 100-EUP-159; prepared by
Industrial Bio-Test Laboratories, Inc., for Ciba-Geigy Corp.,
Greensboro, NC; including Addendum A - Validation by Ciba-Geigy Corp.;
CDL: 232191-A.)
Nham, D., and W. A. Harrison, 1977. Report to Ciba-Geigy Corp.:
Acute dermal toxicity study with Dual. 8E in albino rabbits: IBT No.
8530-10822. (Unpublished study received November 8, 1977 under 100-
EUP-59; prepared by Industrial Bio-Test Laboratories, Inc., for Ciba-
Geigy Corp., Greensboro, NC; including Addendum B - Validation by
Ciba-Geigy Corp.; CDL: 232191-B.)
Sachsse, K., 1973a. Irritation of technical CGA-24705 in the rabbit
eye: Project No. Siss 2979. (Unpublished study received September
26, 1974 under 5G1553; prepared by Ciba-Geigy Ltd., Basle,
Switzerland; CDL: 112840-G.)
19
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U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevarjd, 12th Floor
Chicago, IL 60604-3590
-------
Sachsse, K., 1973b. Skin irritation in the rabbit after single
application of technical CGA-24705: Project No. Siss 2979.
(Unpublished study received September 26, 1974 under 5G1553; prepared
by Ciba-Geigy Ltd., Basle Switzerland; CDL: 112840-1.)
Sachsse, K., 1977. Skin sensitizing (Contact Allergenic) effect in
guinea pigs of technical CGA-24705. Project No. Siss 5726.
(Unpublished study received October 17, 1977; prepared by Ciba-Geigy
Ltd., Basle; Switzerland.)
Sachsse, K., and Ullman, L., 1974. Acute toxicology to rainbow trout,
crucian carp, channel catfish, bluegill, and guppy of technical CGA-
24705: Project No. Siss 3516. (Unpublished study received September
26, 1974 under 5G1553; prepared by Ciba-Geigy, Ltd., Basle,
Switzerland; that includes a cable from Ciba-Geigy Corp., Greensboro,
NC on fish name change; CDL: 112840-N.)
Scibor, G., 1977a. Report to Ciba-Geigy Corporation: Eye irritation
tests with Dual 8E in albino rabbits: IBT No. 8530-1082.
(Unpublished study received November 8, 1977 under 100-EUP-59;
prepared by Industrial Bio-Test Laboratories, Inc., for Ciba-Geigy
Corp., Greensboro, NC; including Addendum D - Validation by Ciba Geigy
Corp.; CDL: 232191-D.)
Scibor, G., 1977b. Report to Ciba-Geigy Corporatio26, 1974 under
5G1553; prepared by Ciba-Geigy, Ltd., Basle, Switzerland; that
includes a cable from Ciba-Geigy Corp., Greensboro, NC on fish name
change; CDL: 112840-N.)
Scibor, G., 1977a. Report to Ciba-Geigy Corporation: Eye irritation
tests with Dual 8E in albino rabbits: IBT No. 8530-1082.
(Unpublished study received November 8, 1977 under 100-EUP-59;
prepared by Industrial Bio-Test Laboratories, Inc., for Ciba-Geigy
Corp., Greensboro, NC; including Addendum D - Validation by Ciba-Giegy
Corp., CDL: 232191-D.)
Scibor, G., 1977b. Repot to Ciba-Geigy Corporation: Primary skin
irritation test with Dual, BE in albino rabbits: IBT No. 8530-10822.
(Unpublished study received November 8, 1977 under 100-EUP-059;
prepared by Industrial Bio-Test Laboratories, Inc., for Ciba-Geigy
Corp., Greensboro, NC, including Addendum E - Validation by Ciba Geigy
Corp.; CDL: 232191-E.)
Smith, K. S., 1,977. Report: catfish bioaccumulation study following
exposure to 14c-metolachlor in a soil/water/fish ecosystem. 7E-6506.
(Unpublished study received February 6, 1978 under 100-583; prepared
by Cannon Laboratories, Inc., for Ciba-Geigy Corp., Greensboro, NC;
CDL: 232789-U.)
Vilkas, A. G., 1976. Acute toxicity of CGA-24705 technical to the
water flea Daphnia magna. Received November 23, 1976 under 100-587.
(Unpublished study prepared by Aquatic Environmental Sciences, Union
Carbide Corp., for Ciba-Geigy Corp., Greensboro, NC; CDL: 226955-C.)
20
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