Page 1 of 38

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460

MEMORANDUM Date 05/06/2015

Subject: Registration Review –Preliminary Problem Formulation for Ecological 

Risk and Environmental Fate, Endangered Species, and Drinking Water 

Assessments for Cycloate

PC Code: 041301

DP Barcode: 424436

To: Mathew Manupella, Chemical Review Manager

Kevin Costello, Branch Chief

Risk Management and Implementation Branch 2

Pesticide Re-evaluation Division (PRD)

From: Christine Hartless, Ph.D., Wildlife Biologist

James Lin, Ph.D., Environmental Engineer

Environmental Risk Branch 2

Environmental Fate and Effects Division

Office of Pesticide Programs

Reviewed: Gregory Orrick, Environmental Scientist

Jean Holmes, RAPL

Environmental Risk Branch 2

Environmental Fate and Effects Division

Office of Pesticide Programs

Through: Brian Anderson, Branch Chief

Environmental Risk Branch 2

Environmental Fate and Effects Division

Office of Pesticide Programs

The Environmental Fate and Effects Division (EFED) has completed the preliminary 

problem formulation (attached) for the ecological risk, environmental fate, endangered 

species, and drinking water assessments to be conducted as part of the registration review 

of the herbicide cycloate. 

The problem formulation draws on information from both open literature and studies 

submitted by the technical registrants in response to data requirements. This document is 

intended to provide an overview of what is currently known regarding the environmental 

fate and ecological effects associated with cycloate and outlines uncertainties regarding 
Page 2 of 38

attributes of the parent compound and its transformation products. It describes the 

preliminary ecological risk hypothesis and the processes that will be used during the 

completion of drinking water and ecological risk assessments in support of registration

review. This document also recommends studies that should be included in a data call-in 

(DCI) to address uncertainties surrounding the environmental fate and potential 

ecological effects of cycloate.
Page 3 of 38

Preliminary Problem Formulation for the 

Environmental Fate and Ecological Risk, Endangered 

Species, and Drinking Water Assessments in Support of 

the Registration Review of Cycloate

N-ethyl-N-cyclohexyl-S-ethylthiocarbamate

(CAS 1134-23-2)

(PC Code 041301)

Environmental Risk Branch II

Environmental Fate and Effects Division

Christine Hartless, Ph.D., Wildlife Biologist

James Lin, Ph.D. Environmental Engineer

Reviewed by:

Gregory Orrick, Environmental Scientist

Jean Holmes, DVM, RAPL

Brian Anderson, Branch Chief

U. S. Environmental Protection Agency

Office of Pesticide Programs

1200 Pennsylvania Ave., NW

Mail Code 7507P

Washington, DC 20460
Page 4 of 38

Table of Contents

1. Executive summary........................................................................................................ 5

2. Introduction.................................................................................................................... 6

3. Use Characterization...................................................................................................... 6

4. Conclusions from Previous Risk Assessments.............................................................. 8

5. Environmental Fate and Transport................................................................................ 10

6. Receptors...................................................................................................................... 15

7. Exposure Pathways of Concern ................................................................................... 16

8. Analysis Plan ................................................................................................................ 17

8.1 Stressors of Concern........................................................................................... 17

8.2 Measures of Exposure ........................................................................................ 17

8.3 Measures of Effect ............................................................................................. 18

9. Endangered Species Assessment ................................................................................. 18

10. Endocrine Disruptor Screening Program............................................................... 18

11. Preliminary Identification of Data Gaps.................................................................... 18

11.1. Fate...................................................................................................................... 18

11.2. Effects................................................................................................................. 19

12. References.................................................................................................................. 24

Appendix A. Ecotoxicity Data for Cycloate ................................................................ 34

Appendix B. Screening Level Models to Evaluate Potential Importance of Drinking 

Water and Inhalation Exposure Pathways .................................................................... 37
Page 5 of 38

1. Executive summary

The Environmental Fate and Effects Division (EFED) has completed the preliminary 

problem formulation for the ecological risk, environmental fate, endangered species, and 

drinking water assessments to be conducted as part of the registration review of cycloate. 

The problem formulation describes the methods planned to be used during the completion 

of drinking water and ecological risk assessments in support of registration review and 

provides an overview of the environmental fate, ecological effects, and potential risks 

associated with the use of cycloate as well as uncertainties unique to risk assessment of 

cycloate. This document also identifies additional studies that would be beneficial to the 

conduct of an ecological risk assessment. 

Data needs for ecological effects are:

 Mysid acute toxicity test (850.1035)

 Fish acute toxicity test, marine (850.1075)

 Freshwater invertebrate life-cycle test (850.1350)

 Freshwater fish early-life stage test (850.1400)

 Avian acute oral toxicity test (850.2100), one passerine species

 Avian inhalation, one species. Suggest to follow 870.1300 modified for birds or 

885.1400 modified for a single exposure; protocol to be submitted to Agency for 

review prior to conduct of study.

 Avian reproduction toxicity test (850.2300), two species

 Acute oral toxicity to adult honey bees (Non-guideline, OECD TG 213)

 Acute oral toxicity to larval honey bees (Non-guideline, OECD TG 237)

 Chronic oral toxicity to larval honey bees (Non-guideline)

 Chronic oral toxicity to adult honey bees (Non-guideline)

 Field trial of residues in pollen and nectar (Non-guideline)

 Semi-field testing for pollinator (Non-guideline, OECD Guidance 75)

 Field testing for pollinators (OCSPP Guideline 850.3040)

 Seedling emergence toxicity test (850.4100), 10 species

 Vegetative vigor toxicity test (850.4150), 10 species

 Aquatic plant toxicity test using Lemna spp. (850.4400)

 Algal toxicity test (850.4500), three species

 Cyanobacteria toxicity test (850.4550)

Data needed for environmental fate and exposure assessment are:

 Photodegradation on soil (835.2410)

 Aerobic soil metabolism (with 3 additional soils) (835.4100)

 Aerobic aquatic metabolism (with 2 systems) (835.4400)

 (835.6100) ECM and ILV for Terrestrial Field Dissipation Study
Page 6 of 38

2. Introduction

Cycloate (N-ethyl-N-cyclohexyl-S-ethylthiocarbamate) is a member of the 

(mono)thiocarbamate class of herbicides, which includes molinate, thiobencarb, 

vernolate, pebulate, butylate, triallate, diallate and EPTC. Cycloate is a systemic 

chemical that inhibits the shoot of emerging seedlings. It is most efficacious when the 

chemical is applied above the seeds so that the immature shoots grow up and reach the 

chemical. Cycloate is used as a pre-emergent herbicide to control annual grasses, 

nutgrass, certain perennial grasses and many broadleaf weeds on sugar beets, spinach, 

and table beets. 

Cycloate is required to be incorporated into the ground by ground equipment or by 

irrigation. It is used in irrigation from Center-Pivot, Lateral Move, End Tow and 

Traveler irrigation systems. These irrigation systems contribute spray drift to adjacent 

non-target areas.

The uses in the profile to be evaluated by EFED include sugar beet, garden beet, and 

spinach. EFED evaluated the most recent ecological risk assessments for cycloate in 

association with the updated toxicity, exposure, and usage information to determine if 

sufficient data are available and if further updates are needed to support registration 

review. In addition, EFED considered the latest Agency science policies and risk 

assessment methodologies. The structure of cycloate, as well as the chemical names and 

other identifiers can be found in the chemical identity table in Section 5 of this document. 

3. Use Characterization

Two Section 3 labels (EPA Reg. Nos. 74530-16 and 73637-5) describe identical usage 

scenarios, application rates, and application methods (Table 1). In addition, there are 

seven Section 24C labels for use on either sugar beets or spinach (Table 2). While all the 

Section 3 labels specify one application per growing season, some labeled crops can have

multiple growing seasons per year. Sugar beets have one growing season per year, while 

table beets can have up to two growing seasons per year and spinach may have up to 

three growing seasons per year (EPA 2007, EPA 2012, EPA 2014). Maximum 

application rates per year are needed on the labels for clarity. Currently, labels specify a 

maximum single application rate, but annual maximum rates are not specified. Any 

absence of information on the labels that specifies the maximum single application rate, 

the application interval, the annual maximum rate allowed (lbs a.i./year), or application 

method may result in conservative assumptions. 
Page 7 of 38

Table 1. Methods and rates of application of currently registered uses of cycloate (EPA 

Reg. Nos. 74530-16 and 73637-5).

Crop Application 

Timing

Max. Single 

App. Rate Application Restrictions

Sugar 

Beets*

-Preplant

-At Plant

-Immediately Post 

Planting

3 lbs a.i./acre on 

sandy soils 

4 lbs a.i./acre on 

heavier soils

-No geographic restrictions

-One application per growing season.

-Use on mineral soils only. 

-Use lower rate on sandy soils. Use higher rate on heavier 

soils.

-Late fall, prior to 

ground freeze 4 lbs a.i./acre

-Recommended only in Idaho, Minnesota, Montana, North 

Dakota, Oregon, and Wyoming.

-For fall application, do not apply following spring.

Garden 

Beets*

-Preplant

-At Plant

-Immediately Post 

Planting

3 lbs a.i./acre on 

sandy soils 

4 lbs a.i./acre on 

heavier soils

-No geographic restrictions

-One application per growing season.

-Use on mineral soils only. 

-Use lower rate on sandy soils. Use higher rate on heavier 

soils.

Spinach*

-Preplant

-At Plant

-Immediately Post 

Planting

3 lbs a.i./acre

-Only use in Arkansas, Colorado, Connecticut, Delaware, 

Illinois, Maine, Maryland, Massachusetts, Mississippi, New 

Hampshire, New Jersey, New York, North Carolina, Ohio, 

Oklahoma, Pennsylvania, South Carolina, Texas, Vermont, 

Virginia, and western Tennessee

-One application per growing season.

-Use on sandy, mineral soils only.

4 lbs a.i./acre

-Only use in California.

-One application per growing season.

-Use on sandy, mineral soils only.

* Applications methods include:

- Ground broadcast or band application with mechanical or sprinkler incorporation

- Soil injection

- Impregnation onto dry bulk fertilizer followed by soil incorporation
Page 8 of 38

Table 2. Methods and rates of application of currently registered 24C (Special Local 

Need, SLN) uses of cycloate. *

Crop Reg. No. Application 

Timing

Max. Single 

App. Rate

Application 

Restrictions

Application 

Methods

Sugar 

Beets

ID 010015

Postemergence, 

after first true 

leaves have 

formed.

3-4 lbs a.i./acre -For use in Idaho

Broadcast or 

sprinkler. Incorporate 

mechanically or by 

irrigation.

OR 010022

Postemergence, 

after first true 

leaves have 

formed.

3-4 lbs a.i./acre - For use in Oregon

Broadcast or 

sprinkler. Incorporate 

mechanically or by 

irrigation.

WA 010023

Postemergence, 

after first true 

leaves have 

formed.

3 lbs a.i./acre 

- For use in 

Washington

- Do not apply after 

July 1

Broadcast and 

mechanical 

incorporation. 

Spinach

MI 080004 Preplant 3 lbs a.i./acre - For use in Michigan

Broadcast and 

mechanical 

incorporation.

OR 010023 Preplant 3 lbs a.i./acre - For use in Oregon

Broadcast and 

mechanical 

incorporation.

WA 010021 Preplant 3 lbs a.i./acre - For use in 

Washington

Broadcast and 

mechanical 

incorporation.

Spinach 

for seed WA 020003 Preplant 3 lbs a.i./acre - For use in Washington

Broadcast and 

mechanical 

incorporation.

* All SLNs have EPA Reg. No. 73637-5 as the master label.

4. Conclusions from Previous Risk Assessments

The Agency has conducted previous ecological risk assessments on cycloate that serve as 

a basis for this problem formulation. This is briefly summarized below. No endangered 

species assessments have been conducted for cycloate.

At the time the EFED Reregistration Eligibility Decision (RED) Chapter was signed 

(September 30, 2004), cycloate was registered as a pre-emergent herbicide to control 

annual grasses, nutgrass, certain perennial grasses, and many broadleaf weeds for use on 

sugar beets, garden beets, and spinach. At the time of the RED, the maximum labeled rate 

of application was 4 lbs a.i./acre nationwide and 6 lbs a.i./acre in California. Based on the 

available fate and ecotoxicity data, the following conclusions were presented in the RED:

 No acute risks to terrestrial or aquatic animals were identified.

 Chronic risk to mammals was above concern levels.

 Chronic risk to birds was presumed as avian reproduction data were not available.

 Chronic risk to aquatic organisms was unknown as no early life-cycle or full lifecycle data for fish or aquatic invertebrates were available.
Page 9 of 38

 Risk to terrestrial and aquatic plants was presumed as no plant toxicity data were 

available. 

 Potential risk to terrestrial and aquatic organisms from exposure to the major 

degradate, cycloate sulfoxide is unknown. This degradate was listed as being of 

concern to the Health Effects Division.

 Certain application methods (Center-Pivot, Lateral Move, End Tow, and Traveler 

irrigation systems) may encourage volatilization (from water or moist soils) and 

spray drift of cycloate to non-target plants, thereby increasing the likelihood of 

risk to non-target organisms.

 Cycloate’s environmental fate properties indicate moderate likelihood of 

movement off-site into surface water or ground water. Volatilization may 

predominate in some situations. Although oxidation in air is believed to be rapid, 

the presumed degradate has an intact thiocarbamate moiety that may be 

biologically active.

 Cycloate persists in soil if incorporated into dry soil, but volatilizes rapidly from 

moist soil.

 The field dissipation half-life is on the order of 10 to 40 days.

 The Tier 2 Drinking Water assessment demonstrates that the expected drinking 

water concentrations (1 in 10 year average) will be 6.9 to 10 μg/L if cycloate is 

used at 4 lb a.i./acre.

Environmental fate and ecological effects data were incomplete at the time the RED was 

finalized and a Data-Call-In (DCI) was issued to address the data gaps (Table 3). None of 

these required studies have been submitted to the Agency, and all data gaps are still 

outstanding.

Table 3. Environmental Fate and Ecotoxicity studies requested at the time of 

finalization of the RED.

835.6100 Terrestrial Field Dissipation (including ECM and ILV)

850.1035 Mysid acute toxicity test

850.1075 Fish acute toxicity test, marine

850.1350 Invertebrate Life Cycle Test on TGAI

850.1400 Fish-Early Life Stage on TGAI (estuarine/marine)

850.2300 Avian Reproduction - Bobwhite Quail and Mallard Duck on TGAI

850.4100 Seedling Germination/Seedling Emergence, Tier 1 (10 most 

sensitive species from testing with parent compound) on TEP

850.4150 Vegetative Vigor, Tier 1 (10 most sensitive species from testing 

with parent compound) on TEP

850.4400 Aquatic Plant Growth, Tier 2 (five most sensitive species) on TEP

The most recent drinking water exposure assessment for use in the human dietary risk 

assessment was completed in 2006 (DP Barcode: D314010). This assessment found that 

an upper-bound Tier 2 concentration of parent cycloate in surface water based on the 

California sugar beet scenario is 58 μg/L (acute), 5.0 μg/L (chronic), and 3.2 μg/L 

(cancer) for application through overhead sprinkler irrigation systems (modeled as 
Page 10 of 38

aerial). An assessment of ground water exposure using SCIGROW performed for this 

assessment showed upper bound concentrations of cycloate in ground water were no 

higher than 0.41 μg/L.

5. Environmental Fate and Transport 

Registrant-submitted data defining the physical, chemical, environmental fate and 

transport characteristics associated with cycloate are summarized in Table 4. Cycloate 

has a moderate solubility (75 to 96 mg/L) and moderately high vapor pressure (6.2 x 10-3

torr at 25o C). Henry’s Law constant is calculated as 1.85 x 10-5atm∙m3/mol.

Table 4. General physico-chemical and environmental fate properties of cycloate.

Parameter Value Reference

Selected Physical/Chemical Parameters

Molecular Mass 215.4 g/mol calculated

Water Solubility 75 - 95 mg/L RED

Vapor pressure 6.2 x 10-3torr at 25o C RED

Density 1.0239 kg/L @ 20o C RED

Henry's Law Constant 1.85 x 10-5atm∙m3/mol RED

Hydrolysis t1/2

no evidence of degradation at pH 5, 7, and 9 MRID 00257865

Aqueous Photolysis t1⁄2 219 days MRID 00257865

Soil Photodegradation t1⁄2 7.63 days MRID 00265256

Aerobic Soil metabolism t1⁄2 43 days MRID 00162644, 00264619, 

41582403

Anaerobic Soil metabolism t1⁄2 68 days MRID 00266125

Anaerobic Aquatic t1⁄2 192 days MRID 42997901

Photo-degradation in Air t1⁄2 5.2 hours MRID 42541101

Terrestrial Field Dissipation t1⁄2

10 days in top 6 in. of soil (FL)

22 days and 40 days in top 12 in. of soil (MS)

11 days in top 3 in. of soil (CA)

MRID 00254904

Adsorption/Desorption

Kads: 9.0 (silt loam); 10.0 (loam), 2.18 (sandy 

loam), and 8.13 (clay) mL/g. Koc 500 – 678 ml/g

Kdes: 11.5 (silt loam), 12.3 (loam), 2.98 (sandy 

loam), and 9.63 (clay) mL/g.

MRID 41920603
Page 11 of 38

Table 4. General physico-chemical and environmental fate properties of cycloate.

Parameter Value Reference

Fish Bioaccumulation

After 7 days of exposure, total cycloate residues 

accumulated in bluegill sunfish with max. BCF of 

82x, 670x, and 330x in edible tissues, inedible 

tissues, and whole fish, respectively. 

After 3 days of depuration, the rates of depuration 

were 81%, 93% and 88%, respectively for edible 

tissues, inedible tissues, and whole fish. 

MRID 41920601

Cycloate is stable to hydrolysis and nearly stable to photolysis in water. A literature study 

(MRID 42541101) indicates that volatilized cycloate may have a short lifetime in air (5.2 

hours) due to reaction with hydroxyl radicals. Therefore, non-target organisms are not 

expected to be exposed to cycloate via spray drift or volatility for several days after 

application.

Soil photodegradation study in laboratory showed a half-life of 7.63 days. Laboratory 

metabolism studies yielded half-lives of 43 days (aerobic soil), 68 days (anaerobic soil), 

and 192 days (anaerobic aquatic metabolism). The terrestrial field dissipation studies, 

yielded a half-life of 11 days in the upper 3 inches with a California soil; a half-life of 10 

days in the top 6 inches with a Florida soil; and two half-life values of 22 days and 40 

days in the top 12 inches with Mississippi soils. Cycloate degradates in soil include the 

sulfoxide (which may revert to the parent under reducing conditions) and Nethylcyclohexylamine. Two sets of ring-hydroxy and ring-keto degradates (the 4-

hydroxy-, 4- keto-, 3-hydroxy- and 3-keto- degradates) are also formed in laboratory 

studies. Other degradates seen in laboratory studies include N-cyclohexyl-Nethylformamide and N-ethyl-N-formyl-S-ethyl thiocarbamate.

Laboratory studies show that cycloate tends to sorb to soil under dry conditions, and that 

the sorption is not reversed if the soil is later flooded. However, if the soil is already 

flooded at the time of application, cycloate is easily desorbed and then volatilized over 

time. Koc values (500 to 678 mL/g) indicate that cycloate is moderately mobile in soil. A 

fish BCF study indicates that cycloate bioconcentrates in fish by 330x. 

In summary, cycloate applied to dry soil and immediately incorporated tends to remain 

sorbed to the soil, and dissipates with a half-life on the order of one to two months. 

Cycloate volatilizes from moist soil if not immediately incorporated. Overall, the major 

dissipation route for cycloate in the environment is volatilization followed by 

atmospheric oxidation. 

The environmental transformation products of cycloate with molecular structure are 

tabulated in Table 5.
Page 12 of 38

Table 5. Cycloate and Its Environmental Transformation Products 

Code Name/ Synonym

Chemical Name Chemical Structure Study Type MRID Maximum 

%AR (day)

Final %AR 

(study length)

PARENT

Cycloate

N-ethyl-N-cyclohexyl-S-ethylthiocarbamate

CAS Reg. No. 1134-23-2

Formula: C11H21NOS

MW: 215.4 g/mol

TRANSFORMATION PRODUCTS

FOR

N-cyclohexyl-N-ethylformamide

Formula: C17H29NO3S

MW: 281 g/mol

Anaerobic Aquatic 

Metabolism 42997901 0.68% (181 day) 0.13% (365 day)

Soil Photodegradation 00265256 2.2% (192 hr) 2.2% (192 hr) 

3HC

S-ethyl N-ethyl-N-(cis/trans-3-hydroxycyclohexyl)carbamothioate

Formula: C15H25NO2S

MW: 283 g/mol Anaerobic Aquatic 

Metabolism 42997901 0.33% (90 day) -- (365 day)
Page 13 of 38

Code Name/ Synonym

Chemical Name Chemical Structure Study Type MRID Maximum 

%AR (day)

Final %AR 

(study length)

4-KC

S-ethyl N-ethyl-N-(4-oxo-cyclohexyl)carbamothioate

Formula: C17H29NO4S

MW: 343 g/mol

Anaerobic Aquatic 

Metabolism 42997901 0.23% (181 day) 0.1% (365 day)

ECA

N-ethylcyclohexylamine

Formula: C15H25NO2S

MW: 283 g/mol

Anaerobic Aquatic 

Metabolism 42997901 0.63% (269 day) 0.3% (365 day)

Soil Photodegradation 00265256 17.3% (192 hr) 17.3% (192 hr)

Aerobic Soil 

Metabolism 41582403 7.3% (38 day) 3% (120 day)

4-HC

S-ethyl N-ethyl-N-(cis/trans-4-hydroxycyclohexyl)carbamothioate

Formula: C15H25NO2S

MW: 283 g/mol

Anaerobic Aquatic 

Metabolism 42997901 0.235 (181 day) 0.1% (365 day)

3-KC

S-ethyl N-ethyl-N-(3-oxo-cyclohexyl)carbamothioate

Formula: C15H25NO2S

MW: 283 g/mol Anaerobic Aquatic 

Metabolism 42997901 0.13% (181 day) -- (365 day)
Page 14 of 38

Code Name/ Synonym

Chemical Name Chemical Structure Study Type MRID Maximum 

%AR (day)

Final %AR 

(study length)

Cycloate Sulfoxide

Formula: C15H25NO2S

MW: 283 g/mol

Aerobic Soil 

Metabolism

162644

264619 16% (31 day) 1% (120 day)

Soil Photodegradation 00265256 6.5% (60 hr) 4.9% (192 hr)

Cycloate Sulfone

Formula: C15H25NO2S

MW: 283 g/mol

Soil Photodegradation 00265256 2.5% (60 hr) 1.4% (192 hr)

Cyclohexylamine

Formula: C15H25NO2S

MW: 283 g/mol

Soil Photodegradation 00265256 2.6% (120 hr) 2.2% (192 hr)
Page 15 of 38

6. Receptors

Table 6 provides a summary of the taxonomic groups and the surrogate species tested to 

characterize the potential acute and chronic ecological effects of cycloate. In addition, 

the table provides a preliminary overview of the potential acute toxicity of cycloate by 

providing the acute toxicity classifications. No ecotoxicity data are available for any 

degradates of cycloate.

Cycloate is practically non-toxic to birds on an acute oral basis, practically non-toxic to 

birds on a subacute dietary exposure basis, slightly toxic to mammals on an acute oral 

exposure basis, and practically non-toxic to honey bees on a contact basis. Data on the 

toxicity of cycloate to terrestrial plants have not been submitted to the Agency. 

Technical grade cycloate is classified as moderately toxic to freshwater fish and as 

moderately toxic to slightly toxic to aquatic invertebrates on an acute exposure basis. 

Acute estuarine/marine fish and invertebrate data as well as chronic exposure effect data 

to cycloate for fish and invertebrates have not been submitted to the Agency. In addition, 

no toxicity data for aquatic plant studies have been submitted to the Agency. 

A review of the Ecological Incident Information System (EIIS, version 2.1) and the 

Avian Monitoring Information System (AIMS) was completed on August 7, 2014, and no 

ecological incidents involving cycloate or cycloate sulfate were identified. Incident 

databases will be reviewed again at the time of the risk assessment. 

Table 6. Test Species Evaluated for Assessing Potential Ecological Effects of Cycloate.

Taxonomic 

Group Study Type Tested Species Toxicity Endpoint

Acute Toxicity 

Classification/

NOAEC most 

sensitive endpoint(s)

Source MRID

Birds1

Acute oral

Bobwhite quail 

(Colinus 

virginianus)

LD50 >2150 mg a.i./kg-bw Practically non-toxic Acc# 072166

Dietary Bobwhite quail LC50 >5620 mg a.i./kg-diet Practically non-toxic 00145554

Chronic No data

Mammals

Acute oral

Laboratory rat 

(Rattus 

norvegicus)

LD50 = 2275 mg a.i./kg-bw Slightly toxic 00132790

Chronic Laboratory rat NOAEC = 8 mg a.i./kg/day

LOAEC = 25 mg a.i./kg/day

decreased weight, 

decreased pup 

survival (72 mg

a.i./kg/day)

00132795

Terrestrial 

invertebrates

Acute 

contact

Honey bee

(Apis 

mellifera)

LD50 = 29 μg a.i./bee Practically non-toxic 00036935

Freshwater 

fish2 Acute

Rainbow trout

Oncorhynchus 

mykiss

LC50 = 4.5 mg a.i./L Moderately toxic Acc# 090620
Page 16 of 38

Table 6. Test Species Evaluated for Assessing Potential Ecological Effects of Cycloate.

Taxonomic 

Group Study Type Tested Species Toxicity Endpoint

Acute Toxicity 

Classification/

NOAEC most 

sensitive endpoint(s)

Source MRID

Chronic No data

Freshwater 

invertebrates

Acute Waterflea

Daphnia magna EC50 = 24 mg a.i./L Slightly toxic 00143655

Chronic No data

Estuarine/

marine fish

Acute and 

Chronic No data

Estuarine/

marine 

invertebrates

Acute and 

Chronic No data

Terrestrial 

plants

Seedling 

emergence

No data

Vegetative 

vigor No data

Aquatic 

plants and 

algae

Vascular No data

Nonvascular No data

1 Birds represent surrogates for terrestrial-phase amphibians and reptiles.

2 Freshwater fish are used as surrogates for aquatic-phase amphibians.

7. Exposure Pathways of Concern

The environmental fate properties and use patterns of cycloate indicate that drift, runoff, 

leaching to ground water, and movement through the affected plants represent potential 

transport mechanisms of cycloate to aquatic and terrestrial organisms. 

Drinking water and inhalation exposure pathways were screened using the SIP 

(Screening Imbibition Program) and STIR (Screening Tool for Inhalation Risk) screening 

methods SIP and STIR are described in detail at: 

http://www.epa.gov/oppefed1/models/terrestrial/index.htm. The drinking water pathway 

was found to be an exposure pathway of potential concern for chronic risks to mammals.

Chronic risk to birds through the drinking water exposure pathway could not be assessed 

as no reproduction toxicity data were available for birds. The inhalation exposure 

pathway was found to be an exposure pathway of concern for birds due to the high 

volatility of cycloate. SIP and STIR results are presented in Appendix B.
Page 17 of 38

8. Analysis Plan 

8.1 Stressors of Concern

i. Ecological Risk 

The stressor of ecological concern for terrestrial and aquatic organisms is parent cycloate. 

The 2003 Metabolism Assessment Review Committee (MARC) memo (DPbarcode 

D295670) listed several degradates of concern for residues in rotational crops and in 

livestock. No degradates were identified as residues of concern in drinking water. Of 

those degradates identified residues of concern in rotational crops and livestock, none 

were observed as major degradates in any of the reviewed environment fate studies. Since 

the likelihood that the identified HED degradates of concern will be found in soil and 

water matrices is low, the EFED ecological risk assessment will only consider parent 

cycloate. 

ii. Drinking Water 

A new drinking water assessment will be conducted using the up-to-date modeling tools 

of SWCC (Surface Water Concentration Calculator) and PRZM-GW (Pesticide Root 

Zone Model – Ground Water), and any new submitted e-fate data according to current 

OPP guidance for drinking water exposure assessment. According to a 2003 MARC 

memo (DPbarcode D295670), the residue of concern for drinking water is cycloate parent 

compound only.

8.2 Measures of Exposure 

i. Ecological Exposure 

EFED will use standard available models to evaluate potential exposures to aquatic and 

terrestrial organisms as described at 

http://www.epa.gov/pesticides/science/models_db.htm. As cycloate is a systemic 

chemical, exposure to terrestrial organisms may occur when feeding on plants containing 

cycloate residues. Magnitude of residue data reviewed by HED will be used as screening 

level estimates of cycloate concentrations in various plant components. 

Screening level calculations suggest that the drinking water pathway may be significant

in causing chronic effects to terrestrial organisms. In addition, screening level 

calculations indicate that inhalation of cycloate in vapor phase may result in exposures 

that may cause toxic effects. These exposure pathways may be further considered at the 

time of the risk assessment (Appendix B). 

The Agency is aware of monitoring conducted by federal and state agencies. These data

will be considered in the assessment to the extent that they are available.
Page 18 of 38

8.3 Measures of Effect 

Toxicity data presented in Section 6 of this problem formulation will be used to calculate 

risk quotients. Any additional information submitted by the registrant or found in the 

open literature prior to conduct of the risk assessment will also be considered. The open 

literature studies are identified using EPA’s ECOTOXicology database (ECOTOX) 

(USEPA, 2007c), which employs a literature search engine for locating chemical toxicity 

data for aquatic life, terrestrial plants, and wildlife. The evaluation of both sources of 

data can also provide insight into the direct and indirect effects of pesticides on biotic 

communities from loss of species that are sensitive to the chemicals and from changes in 

structure and functional characteristics of the affected communities.

9. Endangered Species Assessment

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), 

the Agency will evaluate risks to federally threatened and/or endangered (listed) species 

from registered uses of pesticides in registration review. The process for evaluating 

potential risks to listed species is further described at 

http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm.

10. Endocrine Disruptor Screening Program

Cycloate was not included in the first group or the second group of chemicals issued an 

order to conduct Tier 1 EDSP testing. For additional information the EDSP program, 

visit http://www.epa.gov/endo/. 

11. Preliminary Identification of Data Gaps 

11.1. Fate

The environmental fate database for cycloate is not complete (Table 7). The following 

studies are data gaps: (1) soil photodegradation study, (2) aerobic soil metabolism study 

(with 3 additional soil types), (3) aerobic aquatic metabolism study (with 2 systems), and 

(4) Environmental Chemistry Method (ECM) and Independent Laboratory Validation 

(ILV) for the terrestrial field dissipation study.
Page 19 of 38

Table 7. Available environmental fate data for cycloate and remaining data gaps.

158

Guideline

(OPPTS)

Description MRID Classification Data Gap? Comments

835.1240

(163-1)

Adsorption/Desorption MRID 41920603 acceptable no data requirement satisfied

835.1410

(163-2)

Laboratory Volatility MRID 41920602 acceptable no data requirement satisfied

835.2120

(161-1)

Hydrolysis MRID 00257865 acceptable no data requirement satisfied

835.2240

(161-2)

Photodegradation in water MRID 00257865 acceptable no data requirement satisfied

835.2410

(161-3)

Photodegradation on soil MRID 00265256 unacceptable yes data requirement not satisfied; 

chemigation is allowed on the 

label; additional data are needed

835.2370 

(161-4)

Photodegradation in air MRID 42541101 acceptable no data requirement satisfied

835.4100

(162-1)

Aerobic soil metabolism MRID 00162644

MRID 00264619

MRID 41582403

acceptable yes data requirement not satisfied; 

data on 3 additional soils are 

needed

835.4200

(162-2)

Anaerobic soil metabolism MRID 00266125 acceptable no data requirement satisfied

835.4300

(162-4)

Aerobic Aquatic Metabolism (none) (not applicable) yes a study of 2 systems is needed

835.4400

(162-3)

Anaerobic Aquatic 

Metabolism

MRID 42997901 acceptable no data requirement not satisfied; but 

additional data are not needed

835.6100

(164-1)

Terrestrial Field Dissipation MRID 41920603 supplemental no additional TFD study is not 

required

850.1730

(165-4)

Fish Bioconcentration Factor MRID 41920601 acceptable no data requirement satisfied

850.6100 Environmental Chemistry 

Method: Soil and water

none NA yes needed to support potential 

monitoring

850.6100 Independent Laboratory 

Validation: Soil and water

none NA yes needed to support potential 

monitoring

11.2. Effects

Tables 8 and 9 identify ecological effects studies by MRID that offer data for each 

guideline requirement, as well as study classifications and whether or not further data are 

needed in order to support risk assessment. 

Although cycloate is categorized as practically non-toxic to adult honeybees on contact 

exposure basis, and by extension, to other beneficial terrestrial invertebrates on an acute 

exposure basis, there is considerable uncertainty regarding the potential effects of the 

compound on honeybee larval development and survival as well as potential for chronic 

effects. Therefore, additional data on pollinators is needed to fully characterize the risk 

associated with cycloate use to all developmental stages of honeybees, as sensitivity may 

vary according to life-stage and length of exposure (adult vs. larval and acute vs. chronic, 
Page 20 of 38

respectively). Additional information is needed, but uncertainty associated with risks to 

honey bees need to be evaluated with more data to different life stages. Cycloate is 

systemic in plants so exposure via pollen and nectar is possible; and therefore, residues of 

pollen and nectar of crops are an additional data need. Open literature data is needed to 

help better characterize some uncertainties regarding potential effects to bees and other 

non-target terrestrial invertebrates. In addition, higher tier effects toxicity tests (i.e., 

semi-field and/or field studies – Tier II and Tier III, respectively) may be needed, based 

on the results of the larval and chronic adult toxicity studies. Higher tier studies are 

recommended if the ratio of the EEC and larval or adult bee acute LD50>0.4 or the ratio 

of the EEC and the chronic NOAEC>1. Incident data and/or compelling open literature 

studies can also be used to support the need for higher tier studies. Should the screening 

level risk assessment identify that there are risk concerns to bees, mitigation measures 

may need to be considered or the registrant may need to conduct Tier II or Tier III effects 

studies (e.g. OECD Guideline 75 and/or 850.3040 guideline studies) that reduce 

uncertainty by characterizing cycloate’s effects at the whole-colony level 

(http://www2.epa.gov/pollinator-protection/pollinator-risk-assessment-guidance). These 

additional pollinator protection studies are listed in Table 8.

Table 8. Available ecological effects data for terrestrial organisms exposed to cycloate and 

remaining data gaps. 

OCSPP 

Guideline Data Requirement Submitted Studies (MRID)

Study 

Classifications

Are data needed 

for risk 

assessment?

Current Additional Data Need

850.2100 Avian oral toxicity Acc# 072166 Acceptable Yes

Data are required for avian acute 

oral with passerine Acc# 073005 Invalid

Acc# 073005 Invalid

850.2200 Avian dietary toxicity 00145554 Acceptable No --

Acc#072166 Supplemental

Acc#072166 Supplemental

42090306 Acceptable

850.2300 Avian reproduction (None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. Data are 

required for both an upland 

game bird and a water fowl 

species.

Non-guideline Avian inhalation (None) (N/A) Yes A data gap was identified as 

inhalation concerns were raised 

based on the STIR screen.

850.3020 Honey bee acute 

contact toxicity

00036935 Acceptable No

850.3030 Honey bee residue on 

foliage

(None) (N/A) No Data are not requested at this 

time as the adult bee contact 

LD50 was greater than 11 μg 

a.i./bee.
Page 21 of 38

Table 8. Available ecological effects data for terrestrial organisms exposed to cycloate and 

remaining data gaps. 

OCSPP 

Guideline Data Requirement Submitted Studies (MRID)

Study 

Classifications

Are data needed 

for risk 

assessment?

Current Additional Data Need

Non-guideline, 

OECD TG 213

Acute oral toxicity to 

adult honey bees

(None) (N/A) Yes Recommend that PRD request 

data per:

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

Non-guideline, 

OECD TG 237

Acute oral toxicity to 

larval honey bees

(None) (N/A) Yes Recommend that PRD request 

data per: 

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

Non-guideline Chronic oral toxicity 

to adult honey bees

(None) (N/A) Yes Recommend that PRD request 

data per: 

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

Non-guideline Chronic oral toxicity 

to larval honey bees

(None) (N/A) Yes Recommend that PRD request 

data per: 

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

Non-guideline Field trial of residues 

in pollen and nectar

(None) (N/A) Yes Recommend that PRD request 

data per: 

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

Non-guideline, 

OECD 

Guidance 75

Semi-field testing for 

pollinator

(None) (N/A) Yes Recommend that PRD request 

data per: 

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

850.3040 Field testing for 

pollinator

(None) (N/A) Yes Recommend that PRD request 

data per: 

http://www2.epa.gov/pollinatorprotection/pollinator-riskassessment-guidance

850.3100 Earthworm 

Subchronic Toxicity 

Test 

(None) (N/A) No Data have not been submitted to 

fulfill this guideline. A data gap 

was not identified as these data 

are not necessary for risk 

assessment at this time.

850.4100 Seedling Emergence 

and Seedling Growth

(None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. Data are 

required for 10 species. 

850.4150 Vegetative Vigor (None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. Data are 

required for 10 species.
Page 22 of 38

Table 9. Available ecological effects data for aquatic organisms exposed to cycloate

and remaining data gaps. 

OCSPP

Guideline

Data 

Requirement

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct 

risk 

assessment?

Current Additional Data Need

850.1010 Freshwater 

invertebrate 

acute toxicity

00143655 Acceptable No --

05001497 Supplemental

850.1025

850.1035

850.1045

850.1055 

Saltwater 

invertebrate 

acute toxicity 

(None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. 

850.1075 Freshwater fish 

acute toxicity 

41614703 Acceptable No --

Acc# 090620 Acceptable

Acc# 090620 Acceptable

45608401 Acceptable

45608401 Acceptable

45608401 Acceptable

Acc# 072166 supplemental

00143654 Acceptable

00084743 supplemental

850.1075 Saltwater fish 

acute toxicity 

(None) (N/A) Yes Data have not been submitted to 

fulfill this guideline.

850.1300 Freshwater 

invertebrate 

life cycle 

(None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. 

850.1350 Saltwater 

invertebrates 

life cycle 

(None) (N/A) No Data have not been submitted to 

fulfill this guideline. A data gap 

was not identified as these data 

are not necessary for risk 

assessment at this time.

850.1400 Freshwater fish 

early-life stage

(None) (N/A) Yes Data have not been submitted to 

fulfill this guideline.

850.1400 Saltwater fish 

early-life stage 

(None) (N/A) No Data have not been submitted to 

fulfill this guideline. A data gap 

was not identified as these data 

are not necessary for risk 

assessment at this time.

850.1500 Fish life cycle (None) (N/A) No Data have not been submitted to 

fulfill this guideline. A data gap 

was not identified as these data 

are not necessary for risk 

assessment at this time.

850.4400 Aquatic plant 

Toxicity Test 

using Lemna

spp.

(None) (N/A) Yes Data have not been submitted to 

fulfill this guideline.
Page 23 of 38

Table 9. Available ecological effects data for aquatic organisms exposed to cycloate

and remaining data gaps. 

OCSPP

Guideline

Data 

Requirement

Submitted 

Studies 

(MRID)

Study 

Classifications

Are data 

needed to 

conduct 

risk 

assessment?

Current Additional Data Need

850.4500 Algal toxicity (None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. Data are 

required for three species.

850.4550 Cyanobacteria (None) (N/A) Yes Data have not been submitted to 

fulfill this guideline. 
Page 24 of 38

12. References 

Internal Office of Pesticide Program Documents

US EPA 2007. Maximum Number of Crop Cycles Per Year in California for Methomyl Use 

Sites. Memorandum from Monisha Kaul (Biological Economic and Analysis Division, BEAD) to 

Melissa Panger (Environmental Fate and Effects Division, EFED). Signed February 28, 2007.

US EPA 2012. Usage Metrics for Row Crops Estimated from Survey Data. Memorandum from 

Jonathan Becker in Biological Economic and Analysis Division (BEAD). Signed July 31, 2012. 

136 pages.

US EPA 2014. Guidance on Usage Data Available for 19 Field Crops (Version 1). Memorandum 

from Don Brady (Division Director) to Environmental Fate and Effects Division Staff. Signed June 

11, 2014. 11 pages.

Environmental Fate Data Submitted To Support Registration

Guideline: 161-1 Hydrolysis

-------------------------------------------------------------------------------------

MRID: 132550

Stauffer Chemical Co. (1983) ?Residue of Ro-Neet in Corn; Environ- mental Fate Data|. 

(Compilation; unpublished study received Nov 30, 1983 under 476-EX-106; 

CDL:072167-A; 072168) 

MRID: 149662

Myers, H.; Bartell, L. (1983) Hydrolysis Studies of Cycloate: Report No. WRC 83-73. 

Unpublished report prepared by Stauffer Chemical Company. 17 p. 

MRID: 92025018

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00149662. 

Hydrolysis Studies of Cyloate (sic): Report No. WRC-83-73. Prepared by STAUFFER 

CHEMICAL COMPANY. 11 p. 

Guideline: 161-2 Photodegradation-water

-------------------------------------------------------------------------------------

MRID: 148882

Myers, H.; Bartell, L. (1985) Photolysis Study of Cycloate: Report No. 85-22. 

Unpublished report prepared by Stauffer Chemical Company. 8 p. 

MRID: 42249701

Hillebrecht, W. (1992) Addendum Number 1 to MRID 148882: Cycloate 

Photodegradation in Water: Lab Project Number: WRH-1/92. Unpublished study 

prepared by ICI Americas, Inc. 24 p. 

MRID: 92025019

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00148882. 
Page 25 of 38

Photolysis Study of Cycloate; Procedures for Determining the Hydrolytic and Photolytic 

Degradation Rates of Pesticides: Report Nos. RRC-85-22; RRC 84-50. Prepared by 

STAUFFER CHEMICAL COMPANY. 13 p. 

Guideline: 161-3 Photodegradation-soil

-------------------------------------------------------------------------------------

MRID: 93485

Gray, R.A.; Weierich, A.J. (1965?) Behavior and Persistence of S- Ethyl 

Cyclohexylethylthiocarbamate (R-2063) in Soils. (Unpublished study received Feb 14, 

1967 under 7F0522; submitted by Stauffer Chemical Co., Richmond, Calif.; 

CDL:090621-F) 

MRID: 108333

Gray, R.; Weierich, A. (1968) Behavior and Persistence of Thio- carbamate Herbicides in 

Soils under Different Environmental Conditions. (Unpublished study received Nov 4, 

1971 under 1F1042; submitted by Stauffer Chemical Co., Richmond, CA; CDL: 091932-

H) 

MRID: 117144

Gray, R.; Weierich, A. (1965) Persistence of Ro-Neet in Soils. (Unpublished study 

received Nov 29, 1965 under unknown admin. no.; submitted by Stauffer Chemical Co., 

Richmond, CA; CDL: 123664-C) 

MRID: 131466

Gray, R.; Murphy, J. (19??) Breakdown Products of S-Ethyl Cyclohexylethylthiocarbamate (Ro-Neet) in Soils and in Microbial Cultures. (Unpublished 

study received Oct 7, 1983 under 476-1978; submitted by Stauffer Chemical Co., 

Richmond, CA; CDL:251456-D) 

MRID: 163864

Tarr, J. (1986) Photodegradation of [Ring(U)-[carbon 14]]Cycloate on Soil: Lab Project 

ID: PMS-198; MRC-86-12. Unpublished study prepared by Stauffer Chemical Co., 

Mountain View Research Cen- ter. 40 p. 

MRID: 92025020

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00163864. 

Photodegradation of [Ring (u)-Carbon-14] Cycloate on Soil: Report No. MRC-86-12; 

Study No. PMS-198. Prepared by Stauffer Chemical Co. 18 p. 

Guideline: 161-4 Photodegradation-air

-------------------------------------------------------------------------------------

MRID: 42541101

Kwok, E.; Atkinson, R.; Arey, J. (1992) Gas-phase atmospheric chemistry of selected 

Thiocarbamates. Environ. Sci. Technol. 26(9):1798-1807. 
Page 26 of 38

Guideline: 162-1 Aerobic soil metabolism

-------------------------------------------------------------------------------------

MRID: 93485

Gray, R.A.; Weierich, A.J. (1965?) Behavior and Persistence of S- Ethyl 

Cyclohexylethylthiocarbamate (R-2063) in Soils. (Unpub- lished study received Feb 14, 

1967 under 7F0522; submitted by Stauffer Chemical Co., Richmond, Calif.; 

CDL:090621-F) 

MRID: 117144

Gray, R.; Weierich, A. (1965) Persistence of Ro-Neet in Soils. (Unpublished study 

received Nov 29, 1965 under unknown admin. no.; submitted by Stauffer Chemical Co., 

Richmond, CA; CDL: 123664-C) 

MRID: 131466

Gray, R.; Murphy, J. (19??) Breakdown Products of S-Ethyl Cyclohexylethylthiocarbamate (Ro-Neet) in Soils and in Microbial Cultures. (Unpublished 

study received Oct 7, 1983 under 476-1978; submitted by Stauffer Chemical Co., 

Richmond, CA; CDL:251456-D) 

MRID: 131467

Antognini, J.; Gray, R.; Menn, J. (1970) Chemical, physical, toxicological and 

biochemical properties of cycloate. Pages 293- 299, In Proceedings, Second International 

Meeting on Selective Weed Control in Beet Crops: Vol. 1. ?S.l.: s.n|. (Also In unpublished submission received Oct 7, 1983 under 476-1978; sub- mitted by Stauffer 

Chemical Co., Richmond, CA; CDL:251456-E) 

MRID: 162644

Spillner, C. (1986) Ro-neet Aerobic Soil Metabolism Study: Laboratory Project ID: 

PMS-177: MRC-86-07. Unpublished study pre- pared by Stauffer Chemical Co., 

Mountain View Research Center. 71 p. 

MRID: 162956

Spillner, C. (1986) Aerobic Soil Metabolism Study [with] Ro-Neet: Interim Report 1: 

PMS-177: Project No. 148217. Unpublished study prepared by Stauffer Chemical Co., 

Mountain View Research Center in cooperation with Analytical Development Corp. 33 

p. 

MRID: 41582403

Spillner, C. (1989) Identification of Cycloate Soil Metabolites: Aerobic Soil Metabolism: 

Lab Project Number: PMS-306: RR 89-063B. Unpublished study prepared by ICI 

Americas Inc. 56 p. 

MRID: 92025021

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00162644. RoNeet Aerobic Soil Metabolism Study: Report No. MRC 86-07; Study No. PMS-177. 

Prepared by Stauffer Chemical Company. 20 p. 
Page 27 of 38

Guideline: 162-2 Anaerobic soil metabolism

-------------------------------------------------------------------------------------

MRID: 162652

Spillner, C. (1986) Ro-Neet Anaerobic Soil Metabolism Study: Laboratory Project ID: 

PMS-192: MRC-86-09. Unpublished study pre- pared by Stauffer Chemical Co., 

Mountain View Research Center. 37 p. 

MRID: 162957

Carley, S. (1986) Anaerobic Soil Metabolism Study [with] Ro-Neet: Interim Report 1: 

PMS-192: Project No. 148217. Unpublished study prepared by Stauffer Chemical Co., 

Inc., Mountain View Re- search Center in cooperation with Analytical Development 

Corp. 16 p. 

MRID: 165260

Spillner, C.; Carley, S. (1986) Ro-Neet Anaerobic Soil Metabolism Study/Revised: 

Laboratory Project PMS-192-R; MRC-86-09. Unpublished study prepared by Stauffer 

Chemical Co. 38 p. 

MRID: 92025022

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00162652. RoNeet Anaerobic Soil Metabolism Study/ Revised: Report No. MRC-86-09; Study No. 

PMS-192-R. Prepared by Stauffer Chemical Co. 20 p. 

Guideline: 162-3 Anaerobic aquatic metabolism.

-------------------------------------------------------------------------------------

MRID: 42997901

Eya, B.; Carley, S. (1993) Cycloate: Anaerobic Aquatic Soil Metabolism: Lab Project 

Number: RR 93-079B. Unpublished study prepared by Zeneca Inc., Western Research 

Center. 85 p.

Guideline: 163-1 Leaching/adsorption/desorption

-------------------------------------------------------------------------------------

MRID: 20566

Gray, R.A.; Weierich, A.J. (1968) Leaching of five thiocarbamate herbicides in soils. 

Weed Science 16(1):77-79. (Also~In~unpub- lished submission received Apr 25, 1978 

under 476-2180; sub- mitted by Stauffer Chemical Co., Richmond, Calif.; CDL:233576-

B) 

MRID: 68700

Koren, E.; Foy, C.L.; Ashton, F.M. (1968) Phytotoxicity and persistence of four 

thiocarbamates in five soil types. Weed Science 16:172-175. (Also in unpublished 

submission received Jun 23, 1977 under 476-2182; submitted by Stauffer Chemical Co., 
Page 28 of 38

Richmond, Calif.; CDL:230714-F) 

MRID: 68702

Koren, E.; Foy, C.L.; Ashton, F.M. (1969) Adsorption, volatility, and migration of 

thiocarbamate herbicides in soil. Weed Science 17:148-153. (Also in unpublished 

submission received Jun 23, 1977 under 476-2182; submitted by Stauffer Chemical Co., 

Richmond, Calif.; CDL:230714-H) 

MRID: 88543

Gray, R.A.; Weierich, A.J. (1965?) Leaching of Five Thiocarbamate Herbicides in Soils. 

(Unpublished study received Aug 14, 1967 under 8F0639; submitted by Stauffer 

Chemical Co., Richmond, Calif.; CDL:091110-W)) 

MRID: 93485

Gray, R.A.; Weierich, A.J. (1965?) Behavior and Persistence of S- Ethyl 

Cyclohexylethylthiocarbamate (R-2063) in Soils. (Unpub- lished study received Feb 14, 

1967 under 7F0522; submitted by Stauffer Chemical Co., Richmond, Calif.; 

CDL:090621-F) 

MRID: 108333

Gray, R.; Weierich, A. (1968) Behavior and Persistence of Thio- carbamate Herbicides in 

Soils under Different Environmental Conditions. (Unpublished study received Nov 4, 

1971 under 1F1042; submitted by Stauffer Chemical Co., Richmond, CA; CDL: 091932-

H) 

MRID: 115035

Norris, R.; Soliman, K. (1973) Comparative Leachability of Preplant Incorporated 

Sugarbeet Herbicides. (Unpublished study received Apr 12, 1974 under 10065-EX-4; 

submitted by Fisons Corp., Agri- cultural Chemicals Div., Bedford, MA; CDL:127693-

W) 

MRID: 115354

Stauffer Chemical Co. (1967) The Results of Tests on the Amount and Nature of the 

Residue, and the Analytical Methodology: ?Tillam|. (Compilation; unpublished study 

received Jul 30, 1967 under 8F0628; CDL:090822-L) 

MRID: 117144

Gray, R.; Weierich, A. (1965) Persistence of Ro-Neet in Soils. (Unpublished study 

received Nov 29, 1965 under unknown admin. no.; submitted by Stauffer Chemical Co., 

Richmond, CA; CDL: 123664-C) 

MRID: 124072

Hercules, Inc. (1974) Efficacy Data (Weed Control in Sugar Beets). (Compilation; 

unpublished study received Nov 1, 1974 under 5G1574; CDL:095224-B) 

MRID: 131467
Page 29 of 38

Antognini, J.; Gray, R.; Menn, J. (1970) Chemical, physical, toxicological and 

biochemical properties of cycloate. Pages 293- 299, In Proceedings, Second International 

Meeting on Selective Weed Control in Beet Crops: Vol. 1. ?S.l.: s.n|. (Also In unpublished submission received Oct 7, 1983 under 476-1978; sub- mitted by Stauffer 

Chemical Co., Richmond, CA; CDL:251456-E) 

MRID: 131468

Gray, R.; Weierich, A. (1968) Behavior and persistence of thiocarbamate herbicides in 

soils under different environmental condi- tions. Pages 94-101, In Proceedings, 9th 

British Weed Control Conference: Vol. 1. ?S.l.: s.n.|. (Also In unpublished sub- mission 

received Oct 7, 1983 under 476-1978; submitted by Stauf- fer Chemical Co., Richmond, 

CA; CDL:251456-H) 

MRID: 131469

Stanger, C.; Appleby, A. (1971) Effect of soil type and irrigation method on lateral 

movement of cycloate. Weed Science 19(6):709- 711. (Also In unpublished submission 

received Oct 7, 1983 under 476-1978; submitted by Stauffer Chemical Co., Richmond, 

CA; CDL: 251456-J) 

MRID: 144961

Thomas, V.; Dennison, J. (1980) Adsorption and Desorption of [Carb- on 14] ro-neet in 

Keeton Sandy Loam Soil: MRC-B-105; MRC-80-03 Unpublished study prepared by 

Stauffer Chemical Co. 14 p. 

MRID: 162653

Maullis, J. (1986) Ro-Neet Selective Herbicide Soil Leaching Study: Laboratory Project 

ID: PMS-202: MRC-86-05. Unpublished study prepared by Stauffer Chemical Co., 

Mountain View Research Center. 32 p. 

MRID: 41920603

Laster, W. (1991) Cycloate: Adsorption/Desorption in Four Soils: Lab Project Number: 

39229: 91-035B: PMS 359. Unpublished study prepared by ABC Laboratories, Inc. 56 

p. 

Guideline: 163-2 Volatility - lab

-------------------------------------------------------------------------------------

MRID: 41920602

McGahen, L. (1991) Volatility of 14C-Cycloate Applied to Soil: Lab Project Number: 

PMS-343: RR-91-006B. Unpublished study prepared by ICI Americas Inc. Western 

Research Center and Pesticide Metabolism Center. 43 p. 

Guideline: 164-1 Terrestrial field dissipation

-------------------------------------------------------------------------------------

MRID: 68705
Page 30 of 38

Gray, R.A.; Weierich, A.J. (1968) Behavior and persistence of thiocarbamate herbicides 

in soils under different environmental conditions. Proceedings of the 9th British Weed 

Control Conference 9:94-101. (Also in unpublished submission received Jun 23, 1977 

under 476-2182; submitted by Stauffer Chemical Co., Richmond, Calif.; CDL:230714-L) 

MRID: 115029

Brickey, J.; Lardelli, R.; Perelini, E.; et al. (1973) Decline Study for Preplant Sugar Beet 

Herbicides--Woodland: SB-13-72. (Unpublished study received Apr 12, 1974 under 

10065-EX-4; pre- pared by Univ. of California--Davis, Dept. of Botany and Plant 

Pathology, submitted by Fisons Corp., Agricultural Chemicals Div., Bedford, MA; 

CDL:127693-M) 

MRID: 116367

Rademacher, D. (1973) Letter sent to E. Sullivan dated Jul 3, 1973 Results of bio-assay 

run on 1972 applied herbicide test for wheat|. (Unpublished study received Apr 12, 1974 

under 10065- EX-4; prepared by Great Western Sugar Co., submitted by Fisons Corp., 

Agricultural Chemicals Div., Bedford, MA; CDL:127693-P) 

MRID: 124072

Hercules, Inc. (1974) Efficacy Data (Weed Control in Sugar Beets). (Compilation; 

unpublished study received Nov 1, 1974 under 5G1574; CDL:095224-B) 

MRID: 145057

Stauffer Chemical Co. (1984) [Residue Report on Ro-Neet and Dyfon- ate in Soil]: 

Project No: H-315-SRS-77. Unpublished study. 62 p. 

MRID: 41582404

Curry, K. (1989) Ro-Neet 6-E: Field Dissipation Study for Terrestrial Food Crop Uses 

Cycloate, California, 1987-1988: Lab Pro- ject Number: RP 87-02: RR 89-041B. 

Unpublished study prepared by ICI Americas Inc. 185 p. 

MRID: 41582405

Curry, K.; Riggle, B.; Hoag, R. (1989) Ro-Neet 6-E: Field Dissipation Study for 

Terrestrial Food Crop Uses Cycloate California, 1988: Lab Project Number: RSO2-88-

120: RR 89-019B. Unpublished study prepared by ICI Americas Inc. 181 p. 

Guideline: 165-4 Bioaccumulation in fish

-------------------------------------------------------------------------------------

MRID: 145556

McAllister, W.; Franklin, L. (1984) Uptake, Depuration and Biocon- centration of 

(Carbon 14) Ro-Neet by Bluegill Sunfish (Lepomis macrochirus): ABC Final Report 

#31682. Unpublished study pre- pared by Analytical Bio-Chemistry Laboratories, Inc. 

247 p. 

MRID: 41920601
Page 31 of 38

Subba-Rao, R.; Tamichi, E. (1991) Cycloate: Bioaccumulation in Bluegill Sunfish: Lab 

Project Number: RR 91-045B: PMS 354: 39037. Unpublished study prepared by ICI 

America, Inc. 106 p. 

Ecological Toxicity Data Submitted To Support Registration:

Guideline: 71-1 Avian Single Dose Oral Toxicity

-------------------------------------------------------------------------------------

MRID: 132798

Fletcher, D. (1983) Report to ...: Acute Oral Toxicity Study with Ro-Neet Technical in 

Bobwhite Quail: T-11188. (Unpublished study received Nov 30 1983 under 476-EX106; prepared by Bio- Life Assoc., Ltd., submitted by Stauffer Chemical Co., Richmond, 

CA; CDL:072166-A) 

MRID: 92025001

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00132798. Acute 

Oral Toxicity Study with Ro-Neet Technical in Bobwhite Quail: Report No. T-11188; 

BLAL No. 83 QD 32. Prepared by Bio-Life Associates Ltd. 11 p. 

Guideline: 71-2 Avian Dietary Toxicity

-------------------------------------------------------------------------------------

MRID: 132799

Joiner, R. (1975) Safety Evaluation of Ro-Neet Technical by a Five- day Feeding Study 

in Mallard Ducks: T-5471. (Unpublished study received Nov 30, 1983 under 476-EX106; submitted by Stauffer Chemical Co., Richmond, CA; CDL:072166-B) 

MRID: 132800

Knott, W.; Beliles, R. (1966) Ro-Neet 6-E Safety Evaluation by Feeding to Bobwhite 

Quail for Seven Days. (Unpublished study received Nov 30, 1983 under 476-EX-106; 

prepared by Woodard Re- search Corp., submitted by Stauffer Chemical Co., Richmond, 

CA; CDL:072166-C) 

MRID: 145554

Beavers, J. (1984) A Dietary LC50 Study in the Bobwhite with Ro- Neet Technical: Final 

Report: Project No. 144-121. Unpublished study prepared by Wildlife International Ltd. 

14 p. 

MRID: 42090306

Beavers, J. (1985) Ro-Neet Technical: A Dietary LC50 Study with the Mallard: Final 

Report: Lab Project Number: 144-129: SPONSOR. Unpublished study prepared by 

Wildlife International Ltd. 19 p. 

MRID: 92025002

Calderbank, A. (1990) Ici Americas Inc. Phase 3 Summary of MRID 00145554. Ro-Neet 

Technical: A Dietary LC50 Study in the Bobwhite, Final Report: Report No. T-12108: 
Page 32 of 38

Study No. 144-121. Prepared by Wildlife International Ltd. 11 p. 

MRID: 92025003

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00132799. RoNeet Technical: a Dietary LC50 Study with the Mallard: Final Report No. T-12275; 

Study No. 144-129. Prepared by STAUFFER CHEMICAL COMPANY. 11 p. 

Guideline: 72-1 Acute Toxicity to Freshwater Fish

-------------------------------------------------------------------------------------

MRID: 84743

Bullock, C. (1968) Thiocarbamate Herbicides--Mosquito Fish Bio- assay: Toxicologival 

Summary T-1272. (Unpublished study received Oct 8, 1981 under 476-2107; submitted 

by Stauffer Chemical Co., Richmond, Calif.; CDL:246020-G) 

MRID: 93479

Beliles, R.P.; Smart, T. (1965) R-2063: Acute Toxicity in Rainbow Trout. (Unpublished 

study received Sep 1, 1966 under 7F0522; prepared by Woodard Research Corp., 

submitted by Stauffer Chemical Co., Richmond, Calif.; CDL:090620-J) 

MRID: 108342

Bullock, C. (1968) Thiocarbamate Herbicides: Mosquito Fish Bio- assay: Toxicological 

Summary T-1272. (Unpublished study received Nov 4, 1971 under 1F1042; submitted 

by Stauffer Chemical Co., Richmond, CA; CDL:091932-Y) 

MRID: 115089

Beliles, R.; Smart, T. (1965) R-2063: Acute Toxicity in Rainbow Trout. (Unpublished 

study received Feb 25, 1966 under unknown admin. no.; prepared by Woodard Research 

Corp., submitted by Stauffer Chemical Co., Richmond, CA; CDL:104312-A) 

MRID: 132801

Bresolin, P. (1975) Ro-Neet Technical (Lot No. RCK 1501): Laboratory Report T-5285. 

(Unpublished study received Nov 30, 1983 under 476-EX-106; submitted by Stauffer 

Chemical Co., Richmond, CA; CDL:072166-D) 

MRID: 143654

McAllister, W.; Cohle, P. (1984) Acute Toxicity of Ro-Neet Technical to Bluegill 

Sunfish (Lepomis macrochirus): Static Acute Toxicity Report #31561. Unpublished study 

prepared by Analytical Bio-Chemistry Laboratories, Inc. 52 p. 

MRID: 41614703

Tapp, J. ; Sankey, S. ; Caunter, J. ; Stanley, R. et al. (1990) Cycloate: Determination of 

Acute Toxicity to Rainbow Trout (Sal- mo gairdneri): Lab Project Number: 

S057/F/FT42/90. Unpublished study prepared by ICI, Brixham Laboratory. 19 p. 
Page 33 of 38

MRID: 45608401

McCann, J. (1977) Acute Toxicity of Ro-Neet 6E to Rainbow Trout. Unpublished study 

prepared by US EPA, Animal Biology Laboratory. 3 p. 

MRID: 92025004

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00143654. Acute 

Toxicity of Ro-Neet Technical to Bluegill Sunfish (Lepomis macrochirus): Report No. T11464; ABC No. 31561. Prepared by Analytical Biochemistry Laboratories. 11 p. 

Guideline: 72-2 Acute Toxicity to Freshwater Invertebrates

-------------------------------------------------------------------------------------

MRID: 143655

Forbis, A.; Burgess, D. (1984) Acute Toxicity of Ro-Neet Technical to Daphnia magna: 

Static Acute Toxicity Report #31787. Unpublished study prepared by Analytical Biochemistry Laboratories, Inc. 33 p. 

MRID: 92025005

Calderbank, A. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00143655. Acute 

Toxicity of Ro-Neet Technical to Daphnia magna: Report No. T-12107; Study No. 

31787. Prepared by Analytical Biochemistry Laboratories. 10 p. 

Guideline: 72-4 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study

-------------------------------------------------------------------------------------

MRID: 21840

Bullock, C. (1968) Toxicological Summary T-1272: Thiocarbamate Herbicides Mosquito 

Fish Bioassay. (Unpublished study received Mar 27, 1972 under unknown admin. no.; 

submitted by Stauffer Chemical Co., Richmond, Calif.; CDL:120329-Y)
Page 34 of 38

Appendix A. Ecotoxicity Data for Cycloate

Table A1. Acute Oral Toxicity of Cycloate to Birds

Species % ai LD50 (mg 

ai/kg)

Toxicity 

Category

MRID No.

Author/Year

Study 

Classification

Northern bobwhite 

(Colinus virginianus)

98.6 >2150 practically nontoxicAcc# 072166

Fletcher, 1983

Acceptable

Redwing Blackbirds Not 

available

Acc# 073005

Schaffer, 1983

invalid

Starling Not 

available

Acc# 073005

Schaffer, 1983

invalid

Table A2. Subacute Dietary Toxicity to Birds

Species % ai 5-Day LC50

(ppm ai)1

Toxicity 

Category

MRID No.

Author/Year

Study 

Classification

Northern bobwhite quail

(Colinus virginianus) 96.8 >5620 practically non-toxic

00145554

Beavers, 1984 Acceptable

Northern bobwhite quail

(Colinus virginianus) 73.9 >56,000 (8 day) practically non-toxic

Acc#072166

Knotts, 1965 supplemental

Mallard duck

(Anas platyrhynchos) 98.6 >10,000 (8 day) practically non-toxic

Acc#072166

Joiner, 1975 supplemental

Mallard duck

(Anas platyrhynchos) 96.8 >5395 practically non-toxic

42090306

Beavers, 1991 Acceptable

1

 Test organisms observed an additional three days while on untreated feed. 

Table A3. Acute Oral Toxicity of Cycloate to Mammals

Species % ai Test Type Toxicity Value Affected

Endpoints

MRID/Acc. 

No.

Laboratory rat 

(Rattus 

norvegicus)

73.1 Acute oral LD50 = 4195 mg/kg (F)

LD50 = 5460 mg/kg (M)

mortality Acc. No. 

073004

Laboratory rat 7.2 Acute oral LD50 = 3250 mg/kg (F)

LD50 = 4175 mg/kg (M)

mortality 00132271

Laboratory rat 98.0 Acute oral LD50 = 2275 mg/kg (F)

LD50 = 3200 mg/kg (M)

mortality 00132790
Page 35 of 38

Table A4. Reproductive Toxicity of Cycloate to Mammals

Species % ai Test Type Toxicity Value Affected

Endpoints

MRID/Acc. 

No.

Laboratory rat 95.3 Reproduction -

3 generation

NOAEL = 8 

mg/kg/day (160 

ppm)

LOAEL = 24 

mg/kg/day

decreased weight, 

decreased pup survival 

(72 mg/kg/day, 1440 

ppm)

00132795

Laboratory rat 88.3 Reproduction -

2 generation

NOAEL = 50 ppm

LOAEL = 400 ppm

decreased weight gain in 

both generations for 

pups

41691901

(supplemental)

Table A5. Inhalation Toxicity of Cycloate to Mammals

Species % ai Test Type Toxicity Value Affected

Endpoints

MRID/Acc. 

No.

Laboratory rat 73.9 Acute 

Inhalation

LC50>5.03 mg/L 

(one dose)

one mortality, labored 

breathing, tearing, 

salivation

00132792

Laboratory rat 98.4 Inhalation 

21-day

NOAEL = 1.2 ug/L

LOAEL = 12.0 ug/L

brain neuromal, cell 

necrosis

43552101

Table A6. Contact Toxicity of Cycloate to Terrestrial Invertebrates

Species % ai 96-hr LD50 

(μg a.i./bee)

Toxicity Category MRID No.

Author/Year

Study 

Classification

Honey bee

(Apis mellifera)

73.9 29.01 Practically nontoxicMRID 00036935

Atkins et. al., 1975

Acceptable
Page 36 of 38

Table A7. Acute Toxicity of Cycloate to Freshwater Fish

Species % ai 96-hr LC50 

(mg a.i./L)

Toxicity 

Category

MRID No.

Author/Year

Study 

Classification

Rainbow trout 

(Oncorhynchus mykiss)

96.8 7.0 moderately toxic 41614703

Tapp, 1990

Acceptable

Rainbow trout 97.8 4.5 moderately toxic Acc# 090620

Beliles, 1965

Acceptable

Rainbow trout 74.24 5.6 moderately toxic Acc# 090620

Beliles, 1965

Acceptable

Rainbow trout 73.9 10.5 moderately toxic 45608401

McCann, 1977

Acceptable

Rainbow trout 73.9 8.2 moderately toxic 45608401

McCann, 1977

Acceptable

Rainbow trout 73.9 6 moderately toxic 45608401

McCann, 1977

Acceptable

Bluegill sunfish 

(Lepomis macrochirus)

98.6 6.8 moderately toxic Acc# 072166

Bresolin, 1975

supplemental

Bluegill sunfish 96.8 4.6 moderately toxic 00143654

McAllister, 1984

Acceptable

Mosquito fish 

(Gambusia affinis)

formulation 10 moderately toxic 00084743

Bullock, 1968

supplemental

Table A8. Acute Toxicity of Cycloate to Freshwater Invertebrates

Species % ai 48-hr LC50 

(mg a.i./L)

Toxicity Category MRID No.

Author/Year

Study 

Classification

Waterflea 

(Daphnia magna)

96.8 24 Slightly toxic 00143655

Forbis, 1984

Acceptable

Scud Not 

available

05001497

Sanders, 1970

invalid
Page 37 of 38

Appendix B. Screening Level Models to Evaluate Potential 

Importance of Drinking Water and Inhalation Exposure Pathways

SIP (Screening Imbibition Program, v1.0) Inputs and Conclusions

Table 1. Inputs

Parameter Value

Chemical name cycloate

Solubility (in water at 25oC; mg/L) 85

Mammalian LD50 (mg/kg-bw) 2275

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian species

Mammalian NOAEL (mg/kg-bw) 8

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian species

Avian LD50 (mg/kg-bw) 2150

Avian test species northern bobwhite quail

Body weight (g) of "other" avian species

Mineau scaling factor 1.15

Mallard NOAEC (mg/kg-diet)

Bobwhite quail NOAEC (mg/kg-diet)

NOAEC (mg/kg-diet) for other bird species 0

Body weight (g) of other avian species

NOAEC (mg/kg-diet) for 2nd other bird species 0

Body weight (g) of 2nd other avian species

Table 2. Mammalian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 14.6200 14.6200

Adjusted toxicity value (mg/kg-bw) 1749.8403 6.1533

Ratio of exposure to toxicity 0.0084 2.3760

Conclusion*

Drinking water exposure 

alone is NOT a potential 

concern for mammals

Exposure through drinking 

water alone is a potential 

concern for mammals

Table 3. Avian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 68.8500 68.8500

Adjusted toxicity value (mg/kg-bw) 1548.9235 0.0000

Ratio of exposure to acute toxicity 0.0445 0.0000

Conclusion*

Drinking water exposure 

alone is NOT a potential 

concern for birds

Due to insufficient data, risk 

cannot be precluded

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when 

aggregated with other routes (i.e., diet, inhalation, dermal), pesticide exposure through drinking water may contribute 

to a total exposure that has potential for effects to non-target animals.
Page 38 of 38

STIR (Screening Tool for Inhalation Risk, v1.0) Inputs and Conclusions

Input

Application and Chemical Information

Enter Chemical Name cycloate

Enter Chemical Use herbicide

Is the Application a Spray? (enter y or n) y

If Spray What Type (enter ground or air) ground

Enter Chemical Molecular Weight (g/mole) 215.4

Enter Chemical Vapor Pressure (mmHg) 6.20E-03

Enter Application Rate (lb a.i./acre) 4

Toxicity Properties

Bird

Enter Lowest Bird Oral LD50 (mg/kg bw) 2150

Enter Mineau Scaling Factor 1.15

Enter Tested Bird Weight (kg) 0.178

Mammal

Enter Lowest Rat Oral LD50 (mg/kg bw) 2275

Enter Lowest Rat Inhalation LC50 (mg/L) 5.03

Duration of Rat Inhalation Study (hrs) 4

Enter Rat Weight (kg) 0.35

Output

Results Avian (0.020 kg )

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 7.19E+01

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 9.03E+00

Adjusted Inhalation LD50 2.65E+01

Ratio of Vapor Dose to Adjusted Inhalation LD50 3.41E-01 Proceed to Refinements

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 4.23E-01

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 1.59E-02 Exposure not Likely Significant

Results Mammalian (0.015 kg )

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 7.19E+01

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 1.14E+01

Adjusted Inhalation LD50 2.99E+02

Ratio of Vapor Dose to Adjusted Inhalation LD50 3.79E-02 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 5.31E-01

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 1.77E-03 Exposure not Likely Significant