2 

REGISTRATION REVIEW 

PROBLEM FORMULATION ______________________________________________________________________________ 

Zoxamide 

CAS Number 156052-68-5 

US EPA PC CODE 101702 

Prepared by: 

Robin Sternberg, Ph.D., Wildlife Biologist 

Faruque Khan, Ph.D., Senior Fate Scientist 

Environmental Risk Branch 1 

Reviewed by: 

Meghan Radtke, Ph.D., Acting RAPL 

He Zhong, Ph.D., Biologist 

Environmental Risk Branch 1 

U.S. Environmental Protection Agency 

Office of Pesticide Programs 

Environmental Fate and Effects Division 

Environmental Risk Branch I 

1200 Pennsylvania Ave., NW 

Mail Code 7507P 

Washington, DC 20460 
3 

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 zoxamide. 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 

zoxamide as well as uncertainties unique to risk assessment of zoxamide. This document also 

identifies additional studies that would be beneficial to the conduct of an ecological risk 

assessment. 

Major findings include the following data needs and the uncertainty described below: 

 Guideline 835.4100 – Aerobic soil metabolism, two soils (TGAI); 

 Guideline 835.4400 – Anaerobic aquatic metabolism (TGAI); 

 Guideline 850.1735 – Whole sediment acute toxicity invertebrates, freshwater (TGAI); 

 Guideline 850.1740 – Whole sediment acute toxicity invertebrates, marine (TGAI); 

 Guideline 850.2100 – Avian acute oral toxicity test, passerine (TGAI); 

 Guideline 850.4100 – Seedling emergence and seedling growth, corn and ryegrass 

(TEP)1

; and 

 Non-guideline acute larval honey bee feeding study (TGAI). 

Justifications for these data needs as well as assumptions that will be made in the absence of 

these data are provided in Section 11. 

The lack of environmental fate and toxicity data for the major degradates of zoxamide (i.e., RH150721, RH-24549, RH-141288, RH-129151, RH-139432, RH-127450, and RH-163353) is an 

uncertainty in this assessment. In the absence of toxicity data for the degradates, the stressors of 

concern for aquatic organisms are zoxamide and degradates RH-127450, RH-129151, RH141288, and RH-163353, and a conservative method of considering the stressors of concern in 

total, i.e., total toxic residue (TTR) approach, will be used. These degradates are considered 

stressors of concern based on the results of toxicity modeling and/or their structural similarity to 

zoxamide. 

2 Introduction 

Zoxamide is a non-systemic broad-spectrum benzamide fungicide. Zoxamide’s mechanism of 

action involves binding at selective sites along the beta subunits of tubulin which results in the 

arrest of cell division. 

 

1

 The submitted study is classified as “supplemental” because a definitive NOAEC (i.e., NOAEC < 1.3 lb 

zoxamide/A) could not be determined for corn, and there was a 25% effect on ryegrass dry weight. For corn, a 

study that defines a NOAEC (i.e., a concentration that is not statistically different from the negative control for all 

assessed endpoints) is recommended. For ryegrass, a Tier II seedling emergence test is recommended. 
4 

EFED evaluated the most recent ecological risk assessments for zoxamide in association with 

updated toxicity, exposure, and usage information to determine if sufficient data are available 

and if further updates are needed to support Registration Review. Recent risk assessments by 

EFED include a 2001 assessment in support of a Section 3 registration request for use on grapes 

and potatoes (DP 266174 and 254295) and a 2013 assessment in support of a Section 3 

registration request for use on onions (dry bulb), garlic, and shallots (DP 411544). In addition, 

EFED considered the latest Agency science policies and risk assessment methodologies. 

3 Use Characterization 

Zoxamide is a non-systemic, broad-spectrum benzamide fungicide used to control fungicidal 

diseases (e.g., spot, downy mildew, rot, blight, mold, and blotch) on select fruit and vegetable 

crops. It is registered for use on cucurbit vegetables (melons, pumpkin, squash, and 

watermelon), grapes, potatoes (white/Irish), and tomatoes. The proposed new use of zoxamide 

on onions (dry bulb), garlic, and shallots is currently under review by the Agency. Zoxamide is 

formulated as water dispersible granules (dry flowable). Treatment equipment includes aircraft, 

sprayer (ground, handheld), and sprinkler irrigation/system. The chemical profile produced by 

Biological and Economic Analysis Division (BEAD), located in the docket, lists the use patterns 

of maximum exposures (based on pounds of active ingredient applied) for the current uses of 

zoxamide. EFED will use application scenarios that result in maximum exposure scenarios for a 

given use for the risk assessment (see Appendix A for summary of labels). 

4 Conclusions from Previous Risk Assessments 

4.1 Ecological Risk Assessments 

EFED has conducted ecological risk assessments on zoxamide that serve as a basis for this 

problem formulation, including a 2001 assessment in support of a Section 3 registration request 

for use on grapes and potatoes (DP 266174 and 254295) and a 2013 assessment in support of a 

Section 3 registration request for use on onions (dry bulb), garlic, and shallots (DP 411544). The 

results of the 2001 assessment indicated that use of zoxamide on grapes and potatoes may cause 

direct effects to listed freshwater fish and estuarine/marine invertebrates. The results of the 2013 

assessment indicated that the use of zoxamide on onions (dry bulb), garlic, and shallots may 

cause direct effects to: 

 listed freshwater fish from acute exposure and listed and non-listed freshwater fish from 

chronic exposure; 

 listed estuarine/marine invertebrates from acute exposure and listed and non-listed 

estuarine/marine invertebrates from chronic exposure; 

 listed benthic invertebrates from acute exposure; 

 listed aquatic vascular plants and listed and non-listed aquatic non-vascular plants; and 

 listed terrestrial monocots. 

It should be noted that risk quotients (RQs) for aquatic organisms in the 2001 assessment were 

calculated using EECs for parent zoxamide only, even though EECs for zoxamide plus seven 

major degradates (RH-150721, RH-24549, RH-141288, RH-129151, RH-139432, RH-127450, 

and RH-163353) were presented in the assessment. In contrast, RQs for aquatic organisms in the 
5 

2013 assessment were calculated using EECs based on the total toxic residues (TTR) of 

zoxamide (parent zoxamide and selected degradation products including RH-150721, RH141288, RH-127450, and RH-163353). 

The following data gaps were identified in the 2013 assessment: 

 Guideline 835.4100 – Aerobic soil metabolism, two soils; 

 Guideline 835.4400 – Anaerobic aquatic metabolism; 

 Guideline 850.4100 – Seedling emergence and seedling growth, Tier II, corn and 

ryegrass; 

 Guideline 850.2100 – Avian acute oral toxicity test, passerine; 

 Guideline 850.1735 – Whole sediment acute toxicity invertebrates, freshwater; 

 Guideline 850.1740 – Whole sediment acute toxicity invertebrates, marine; and 

 Non-guideline acute honey bee larvae feeding study. 

4.2 Drinking Water Exposure Assessments 

The most recent drinking water exposure assessment for zoxamide was conducted in 2014 for the 

proposed new use on onions (dry bulb), garlic, and shallots (DP 417061). Recommended 

estimated drinking water concentrations (EDWCs) for currently labeled uses were modeled for 

zoxamide (parent only) and the total toxic residues (TTR) of zoxamide – parent zoxamide and 

selected degradation products including RH-150721, RH-24549, RH-141288, RH-129151 and 

RH-139432 – as recommended by the Metabolism Assessment Review Committee (DP 270797) 

and are provided in Table 4-1. 

Table 4-1. Recommended Estimated Drinking Water Concentrations (EDWCs) Based on 

Parent and Total Toxic Residues of Zoxamide (DP 417061)

Drinking Water 

Source 

Crop Scenario Peak Exposure 

(μg/L) 

Annual Mean 

Exposure 

(μg/L) 

Average Annual 

Exposure 

(μg/L) 

Zoxamide (Parent only) 

Surface water NY Grape STD 

Scenario1

17.55 2.49 0.91 

Ground water FL Citrus Scenario2 1.83E-03 NA 6.84E-04 

Total Toxic Residue (Parent +RH-150721, RH-24549, RH-141288, RH-129151 and RH-139432) 

Surface water NY Grape STD 

Scenario1

81.3 54.48 22.84 

Ground water WI corn Scenario2 83.5 NA 65.8 

1

 Reported EDWCs generated using PRZM/EXAMS model for aerial application (US EPA 2000) and these values 

are revised with recommended current PCA factor of 0.91. 2

 Highest EDWCs generated using PRZM-GW model based on 1.60 lbs a.i./A for grape and potato [Gavel 80 WP 

(EPA Reg. No.10163-6413)]

4.3 Clean Water Act Programs 

Zoxamide is not identified as a cause of impairment for any water bodies listed as impaired 

under section 303(d) of the Clean Water Act. No Total Maximum Daily Load (TMDL) criteria 

have been developed for zoxamide. Aquatic benchmarks have been established for zoxamide 

and are available at http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_benchmark.htm. 
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Any data submitted or otherwise located as part of the Registration Review process may be used 

to update aquatic life benchmarks if applicable. 

5 Environmental Fate and Transport 

Zoxamide ([RS]-3,5-dichloro-N-(3-chloro-1-ethyl-1-methyl-2-oxopropyl)-p-toluamide), a broadspectrum benzamide fungicide, comprises equal quantities of two enantiomers, but the Senantiomer is the biologically active component of zoxamide. Physical, chemical and 

environmental fate properties of zoxamide are presented in Table 5-1. Zoxamide has a relatively 

low vapor pressure (<1.0 x 10-07 mm Hg) and Henry’s Law constant (3.26 x 10-11 atm·m3/mol), 

which suggest that volatilization is not expected to be a major route of dissipation from soil and 

water. 

 

Based on registrant-submitted data, zoxamide appears to be relatively non-persistent and 

moderately mobile to slightly mobile under normal use conditions. The major routes of 

dissipation for zoxamide are hydrolysis, photodegradation in water, and microbial-mediated 

degradation in soil and water. Hydrolysis is an important degradation process for zoxamide, and 

the calculated half-lives of zoxamide were 15.5, 15.7 and 8.1 days for pH 4, pH 7 and pH 9, 

respectively. Four major transformation products (RH-150721, RH-24549, RH-141288 and RH129151) were identified. The photodegradation half-life for zoxamide in water was 15.7 days in 

a pH 4 buffer solution, but photodegradation of zoxamide on soil (DT50 of 79 days) does not 

appear to be a major route of dissipation. Several major degradates (RH-150721, RH-24549, 

RH-139432, RH-129151 and RH-127450) were identified in aqueous and soil photolysis studies. 

Zoxamide is also susceptible to microbial-mediated transformation in aquatic and terrestrial 

environments. Zoxamide degraded with half-lives of 37.5 and 38.1 days in an aerobic soil 

metabolism study and with a DT50 of 14.6 days in an anaerobic soil metabolism study. No major 

degradates were observed in aerobic soil metabolism studies. However, two major degradates 

(RH-24549 and RH-127450) were identified in the anaerobic soil metabolism study. Soil bound 

residues accounted for 39 to 56% of the applied radioactivity in these studies. Data also suggest 

that zoxamide is rapidly transformed in water/sediment systems under aerobic conditions (DT50s

of 3.6 to 7.6 days). Several major degradates (RH-24549, RH-127450 and RH-163353) were 

identified in an aerobic aquatic metabolism study. Sediment-bound residues also accounted for 

37% of the applied radioactivity in this study. Field dissipation studies show that zoxamide 

dissipates with half-lives less than 69 days. Degradates were not monitored in field dissipation 

studies. The maximum percent formation of major degradates in various media are listed in 

Appendix B. 

Zoxamide is moderately mobile to slightly mobile (Koc of 815 to 1385 L/Kg) according to the 

FAO classification of mobility in soil (FAO, 2000). Given its high affinity for soil and sediment, 

zoxamide has the potential to move off the site of application during rainfall/irrigation by 

erosion/runoff on soil particles and by drift during application in the field. 
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Table 5-1. Physical, Chemical and Environmental Fate Properties of Zoxamide 

Property Value Source & Study 

Classification 

Common name Zoxamide MRID 44731802 

Acceptable 

CAS Registry No. 156052-68-5 

PC Code 101702 

Chemical name (CAS) 3,5-dichloro-N-(3-chloro-1-ethyl-1-methyl-2-

oxopropyl)-4-methylbenzamide 

SMILES notation C1=C(C(=O)NC(C(CCl)=O)(CC)C)C=C(C(=C1C

l)C)Cl 

EPI Suite, v3.12 

SMILES 

IUPAC name (RS)-3,5-dichloro-N-(3-chloro-1-ethyl-1-methyl-2-

oxopropyl)-p-toluamide 

TOXNET 

Synonyms RH-117281 and RH-7281 

Structure TOXNET 

Molecular formula C14H16Cl3NO2 TOXNET 

Physical and Chemical Properties 

Molecular weight 336.1 TOXNET 

Physical state Fine powder MRID 4431803 

Acceptable 

Vapor pressure <1.33.5 x 10-5 Pa (25oC) 

<1.0 x 10-7 mm Hg (25o

C) 

MRID 4431803 

Acceptable 

Henry’s Law constant 3.26 x 10-11 atm x m3/mol MRID 46515901 

Acceptable 

Specific gravity/density 1.38g/cm3 @ 20oC MRID 44731803 

Acceptable 

Solubility in water 0.681 mg/L @ 25oC 

55.7 g/L in acetone @ 2o

C 

20.0 Ethyl acetate @ 25o

C 

6.49 g/L in n-octanol 

0.038 g/L in n-heptane 

MRID 44731803 

Acceptable 
8 

Property Value Source & Study 

Classification 

log Kow 3.76 ±0.04 (25oC) MRID 44731803 

Acceptable 

Laboratory accumulation in fish 

bioaccumulation factor (BCF) 

(Lepomis macrochirus) 

A depuration half-life 

30x in edible tissues 

360x non-edible (viscera) tissues 

180x for whole body 

464-1670x (lipid adjusted BCF values) 

< 1 day 

MRID 44731932 

Acceptable 

Environmental Fate Properties 

Hydrolysis half-life 

 pH = 5 

 pH = 7 

 pH = 9 

15.5 days 

15.7 days 

8.1 days 

Major Degradates 

RH-150721 (Max 37.6% @ day 21; pH 4.0) 

RH -24549 (Max 30.9% @ day 30; pH 4.0) 

RH-141288 (Max 50.2% @ day 30; pH 9.0) 

RH-129151 (Max 24.5% @ day 21; pH 7.0) 

MRID 44731908 

Acceptable 

Photolysis half-life in water 15.7 days (when the pH 4 hydrolysis DT50 of 15.5 

days was used instead of dark control) 

Major Degradates 

RH-150721 (Max 15.1% @ day 10) 

RH -24549 (Max 27.7% @ day 30) 

RH-139432 (Max 42.4% @ day 30) 

MRID 44731911 

Acceptable 

Photolysis half-life in soil 79 days 

Major Degradates 

RH -24549 (Max 22.2% @ day 30) 

RH-127450 (Max 10.9% @ day 14) 

MRID 44731910 

Acceptable 

Aerobic soil metabolism half-life 38.1 days (loamy sand) 

37.5 days (silt loam) 

No major degradates were detected. 

Minor Degradates 

RH-127450 (Max 6%) 

RH-129151 (Max <2%) 

RH-139432 (Max 1%) 

RH-24549 (Max 7%) 

Maximum bound residue 39% 

MRID 44731912 

MRID 44731913 

Acceptable 

Anaerobic soil metabolism half-life 14.6 days (sandy loam soil) 

Major degradates 

RH -24549 (Max 16.87% @ day 59) 

MRID 44731914 

Acceptable 
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Property Value Source & Study 

Classification 

RH-127450 (Max 13.45% @ day 59) 

Minor Degradates 

RH-141288 (Max <1%) 

RH-141452 (Max <1.0%) 

RH-129151 (Max <1.0%) 

RH-139432 (Max <1%) 

Maximum bound residue 56% 

Aerobic aquatic metabolism half-life 

for total system 

3.6 days (Rhine River) @ 20°C 

7.6 days (Judenweiher pond) @ 20°C 

Major Degradates in total system 

RH-127450 (Max 30.1% @ day 28; Rhine River) 

RH -163353 (Max % 20.6 @ day 56; in Rhine 

River) 

Maximum bound residue 39% 

MRID 44770002 

Acceptable 

Anaerobic aquatic metabolism half-life No data 

Soil adsorption coefficient 

Koc (L/kg) 

Adsorption 

Kd (L/kg) 

3.4 loam 

10.3(sandy loam) 

12.4 (silty clay) 

15.2 (sandy loan) 

25.3 (silty loam) 

Koc (L/kg) 

815 loam 

1196(sandy loam) 

1294 (silty clay) 

1385 (sandy loam) 

1431 (silty loam) 

Desorption 

Kd (L/kg) 

4.2 loam 

11.78(sandy loam) 

10.73 (silty) 

15.56 (sandy loan) 

29.57 (silty loam) 

Koc (L/kg) 

927 loam 

1032(sandy loam) 

1618(silty) 

1671 (sandy loam) 

1671 (silty loam) 

MRID 44731916 

Acceptable 

Terrestrial field dissipation half-life Bare soils multiple applications 

11.5 days in Madera, CA (multiple applications) 

MRID 44732127 

Supplemental 
10 

Property Value Source & Study 

Classification 

17.7 days in Lyons, NY (multiple applications) 

15 days in Lyons, NY (single application) 

9.4 days in Minto, Manitoba 

14.2 days in Branchton, Ontario 

68.6 days in Hunter River, Prince Edward Island 

Major Degradates 

Since no major degradates were detected in the 

aerobic soil metabolism study, transformation 

products of zoxamide were not monitored. 

 

MRID 44732126 

Supplemental 

6 Receptors 

6.1 Zoxamide 

Summaries of the most sensitive toxicity data used to characterize the toxicity of zoxamide to 

terrestrial and aquatic organisms are provided in Table 6-1. Summaries of all submitted toxicity 

data for zoxamide can be found in Appendix C. 

For parent zoxamide, there are no data available for acute oral toxicity to a passerine species, 

acute dietary (oral) toxicity to larval honey bees, and toxicity to benthic invertebrates. 

Based on available data, zoxamide is practically non-toxic to birds on acute oral and subacute/dietary bases; practically non-toxic to mammals on an acute oral basis; practically nontoxic to adult honey bees on an acute contact and oral bases; up to highly toxic to freshwater fish 

on an acute basis; practically non-toxic up to the limit of solubility to estuarine/marine fish on an 

acute basis; at most highly toxic to freshwater invertebrates on an acute basis; and very highly 

toxic to estuarine/marine invertebrates on an acute basis. 

It should be noted that acute toxicity data with a formulation of zoxamide and mancozeb are 

available for freshwater fish, freshwater invertebrates, and aquatic non-vascular plants. These 

acute toxicity endpoints expressed in terms of zoxamide concentrations can be compared to 

zoxamide (parent only) peak EECs from spray drift alone to assess risk from exposure to 

zoxamide as a result of a mixture of zoxamide and mancozeb directly entering a water body via 

spray drift. 

 
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Table 6-1. Summary of Most Sensitive Endpoints from Toxicity Studies with Zoxamide (Synonyms: RH-1

RH-7281) and Zoxamide Co-Formulated with Mancozeb 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

Avian acute oral: single dose, 14-day observation 

RH-117,281 Technical (92.9) 

Bobwhite quail (Colinus virginianus) 

LD50 > 2000 mg a.i./kg-bw (nom) 

NOAEL = 2000 mg a.i./kg-bw (nom) (no mortality or sublethal effects) Practically non-toxic 

NA Passerine species No data 

Avian sub-acute dietary: 5-day exposure; 3-day post-exposure observation 

RH-117,281 Technical (92.9) 

Mallard duck (Anas platyrhynchos)

LC50 > 5250 mg a.i./kg-diet (nom) 

NOAEC = 2625 mg a.i./kg-diet (nom) LOAEC = 5250 mg a.i./kg-diet (nom) (NOAEC based on 10% mortality at 5250 mg/kg-diet; no sublethal effects) Practically non-toxic 

Avian reproduction: 22 weeks (chronic) 

RH-117,281 Technical (92.3) 

Bobwhite quail (Colinus virginianus) Mallard duck (Anas platyrhynchos) 

NOAEC = 1000 mg a.i./kg-diet (nom) LOAEC >1000 mg a.i./kg-diet (nom) (no effects) 

Mammalian acute oral limit: single dose; 14-day observation 

RH-141,455 (98.74) 

Rat (Rattus norvegicus) 

LD50 > 5,000 mg a.i./kg-bw 

NOAEL: not determined (no mortality; scant feces in all males and females on day 1 females on day 2) Practically non-toxic 

Mammalian 2-generation reproduction (chronic) 

RH-117,281 Technical (92.3) 

Rat (Rattus norvegicus) 

Parental, systemic toxicity 

NOAEC = 5,000 mg a.i./kg-diet (409.3 mg a.i./kg-bw/day) LOAEC = 20,000 mg a.i./kg-diet (1624.4 mg a.i./kg-bw/day(based on decreased weights and body weight gains in femaonly) Reproductive toxicity NOAEC ≥ 20,000 mg a.i./kg-diet (2091.2/2239.1 [M/F] mg a.i./kg-bw/day) (based on no effects) 
12 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

Bee acute contact: single dose, 48-hour observation 

RH-117,281 Technical (>95) 

Adult honey bee (Apis mellifera)

LD50 > 100 μg a.i./bee (nom) 

NOAEL = 100 μg a.i./bee (nom) (1-3% mortality across solvent control and 4 treatment concentrations) Practically non-toxic 

Bee acute oral limit: 72 hours 

Form.: Dithane/RH7281 DG Blend Mancozeb (69) Zoxamide (8.26) 

Adult honey bee (Apis mellifera) 

LD50 > 12.6 μg zoxamide/bee#

NOAEL = 12.6 μg zoxamide/bee#

LD50 > 106 μg mancozeb/bee#

NOAEL = 106 μg mancozeb/bee#LD50 >153 μg form./bee 

NOAEL = 153 μg form./bee (0 and 23% mortality in the solvent control and 153 μg formtreatment groups, respectively) Practically non-toxic 

Larval bee acute dietary (oral) 

NA Larval bee No data 

Terrestrial plant seedling emergence: Tier I (limit), 21 days 

TEP: Gavel® 

75DF Mancozeb (64) Zoxamide (8.7) 

Most sensitive monocots: Ryegrass and corn 

Corn (based on height) 

EC25 > 1.3 lb zoxamide/A 

NOAEC < 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC < 10.7 lb mancozeb/A Ryegrass (based on dry weight) 

EC25 = ~1.3 lb zoxamide/A 

NOAEC: Not determineda

EC25 = ~10.7 lb mancozeb/A 

NOAEC: Not determineda

Most sensitive dicot: None 

EC25 > 1.3 lb zoxamide/A NOAEC = 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A 
13 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)NOAEC = 10.7 lb mancozeb/A Most sensitive parameter: None 

Terrestrial plant vegetative vigor: Tier I (limit), 21 days 

TEP: Gavel® 

75DF Mancozeb (64) Zoxamide (8.7) 

Most sensitive monocot: None 

EC25 > 1.3 lb zoxamide/A 

NOAEC = 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC = 10.7 lb mancozeb/A Most sensitive parameter: None 

Most sensitive dicot: None 

EC25 > 1.3 lb zoxamide/A NOAEC = 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC = 10.7 lb mancozeb/A Most sensitive parameter: None 

Freshwater fish acute: 96 hours, flow-through 

RH-117,281 Technical (94.2) 

Rainbow trout (Oncorhynchus mykiss) 

LC50 (95% C.I.) = 156 (134-181) μg a.i./L (mm) 

Probit slope (95% C.I.) = 6.4 (3.9-8.9) NOAEC = 51 μg a.i./L (mm) LOAEC = 140 μg a.i./L (mm) (NOAEC based on signs of toxicity including quiescence, surfacing, dark discoloration, labored respiration, and lying bottom at ≥ 140 μg/L) Highly toxic 

Form.: Dithane/ RH7281 80 WP Mancozeb (71.00) Zoxamide (7.09) 

Rainbow trout (Oncorhynchus mykiss) 

Preliminary endpoints 

LC50 (95% C.I.) = 10 (8-13) μg zoxamide/L (mm) 

NOAEC = 2 μg zoxamide/L (mm) LOAEC = 6 μg zoxamide/L (mm) LC50 (95% C.I.) = 120 (76-176) μg mancozeb/L (mm) NOAEC = 3 μg mancozeb /L (mm) LOAEC = 6.3 μg mancozeb /L (mm) LC50 (95% C.I.) = 159 (129-232) μg form./L (mm) NOAEC = 87 μg form./L (mm) LOAEC = 92 μg form./L (mm) 
14 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)(NOAEC based on mortality and signs of toxicity including dark coloration, slight lethargy, and near base of tank at 92 μform./L) 

Freshwater fish early life stage: 61 days, flow-through (chronic) 

RH-117,281 Technical (92.9) 

14C-RH-117,281 

(98.7) 

Rainbow trout (Oncorhynchus mykiss) 

NOAEC = 3.48 μg a.i./L LOAEC = 6.87 μg a.i./L (based on reduction in fry survival at 35 and 61 days post-ha

Estuarine/marine fish acute: 96 hours, flow-through 

RH-117,281 Technical (92.3) 

Sheepshead Minnow (Cyprinodon variegatus) 

LC50 > 860 μg a.i./L (mm) 

NOAEC = 860 μg a.i./L (mm) (no mortality or sublethal effects up to solubility, i.e., 860 μg

Practically non-toxic up to the limit of solubility 

Estuarine/marine fish early life stage: 28 days, flowthrough (chronic) 

RH-117,281 Technical (92.3) 

Sheepshead Minnow (Cyprinodon variegatus)

NOAEC = 40 μg a.i./L (mm) LOAEC = 78 μg a.i./L (mm) (based on a reduction in wet weight) 

Freshwater invertebrate acute: 48 hours, flowthrough 

RH-117,281 Technical (94.2) 

Water flea (Daphnia magna)

EC50 > 780 μg a.i./L (mm) 

NOAEC = 780 μg a.i./L (mm) (no immobility or sublethal effects; precipitate at highest concentration, considered to be the solubility limit under the conditions of this test) No more than highly toxic 

Form.: Dithane/RH117,281 75 DG BlendMancozeb (69) Zoxamide (8.26) 

Water flea (Daphnia magna)

EC50 (95% C.I.) = 306 (228-400) μg RH-7281 /L (mm) 

Probit slope (95% C.I.) = 3.6 (2.0-5.3) NOAEC = 78.3 μg zoxamide /L (mm) LOAEC = 122 μg zoxamide/L (mm) EC50 (95% C.I.) = 2690 (2020-3580) μg mancozeb/L (mm) Probit slope (95% C.I.) = 3.5 (1.9-5.0) NOAEC = 558 μg mancozeb /L (mm) LOAEC = 1190 μg mancozeb /L (mm) EC50 (95% C.I.) = 3800 (3000-5000) μg form./L (mm) 
15 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)Probit slope (95% C.I.) = 3.8 (3.0-5.0) NOAEC = 820 μg form./L (mm) LOAEC = 1700 μg form./L (mm) (NOAEC based on mortality and the sublethal effect of lying the bottom of the test chamber at ≥ 1700 μg form./L) 

Freshwater invertebrate life cycle: 21 days, flowthrough (chronic) 

RH-117,281 Technical (92.3) 

Water flea(Daphnia magna) 

21-day NOAEC = 39 μg a.i./L (mm) 21-day LOAEC = 74 μg a.i./L (mm) (NOAEC based reduction in parental survival at ≥ 74 μg/L) 

Estuarine/marine invertebrate acute: 96 hours, flowthrough 

RH-117,281 Technical (92.3) 

Mysid shrimp(Mysidopsis bahia) 

LC50 (95% C.I.) = 76 (67-87) μg a.i./L (mm) 

Probit slope (95% C.I.) = 9.0 (5.2-12.9) NOAEC = 17 μg a.i./L (mm) LOAEC = 31 μg a.i./L (mm) (NOAEC based on sublethal effect of erratic swimming at ≥ 

μg/L; lethargy at 132 μg/L – the highest treatment concentraVery highly toxic 

Estuarine/marine invertebrate life cycle: 27 days, flowthrough (chronic) 

RH-117,281 Technical (92.3) 

14C-RH-7281 

(96.3) 

Mysid shrimp(Mysidopsis bahia)

NOAEC = 7.2 μg a.i./L (mm) LOAEC = 14 μg a.i./L (mm) (NOAEC based on a reduction in reproduction and growth [and weight]) 

Benthic invertebrate NA NA No data Aquatic vascular plant: 14 days, staticrenewal 

RH-117,281 Technical (92.3) 

14C-RH-7281 

Technical (96.3) 

Duckweed (Lemna gibba) 

EC50 (95% C.I.) = 19 (16-27) μg a.i./L (mm) 

NOAEC = 9.0 μg a.i./L (mm) LOAEC = 18 μg a.i./L (mm) (NOAEC based on reduction in frond number; smaller-thannormal root size at three highest concentrations) 

Aquatic nonvascular plant: 96 hours, static 

RH-117,281 Technical (92.3) 

14C-RH-117,281 

(96.3) 

Green alga (Scenedesmus subspicatus) 

EC50 (95% C.I.) = 10 (7.8-13) μg a.i./L (mm) 

NOAEC = 7.0 μg a.i./L (mm) LOAEC = 14 μg a.i./L (mm) (NOAEC based on reduction in cell density; clumping/flocculation and cellular enlargement at ≥14 μg a.
16 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

Form.: Dithane/RH117,281 DG Blend  Mancozeb (69) Zoxamide (8.26) 

Green alga (Selenastrum capricornutum) 

EC50 (95% C.I.) = 1.95 (1.52-2.51) μg RH-7281 /L (TWA) 

NOAEC = 0.584 μg zoxamide /L (TWA) LOAEC = 1.16 μg zoxamide/L (TWA) EC50 (95% C.I.) = 9.42 (7.38-12) μg mancozeb/L (TWA) NOAEC = 2.68 μg mancozeb /L (TWA) LOAEC = 5.17 μg mancozeb /L (TWA) EC50 (95% C.I.) = 11.4 (8.91-14.2) μg form./L (TWA) NOAEC = 3.26 μg form./L (TWA) LOAEC = 6.33 μg form./L (TWA) (based on reduction in cell density) 

Abbreviations: C.I. = confidence interval; form. = formulation; im = initial measured; mm = mean measured; nom = nominal; NA = nospecified; TEP = typical end-use product; TWA = time-weighted average # Endpoint calculated by multiplying the concentration in μg form./bee (as reported) by the % a.i. a Given the 25% effect on dry weight, the power of the test was deemed insufficient for determining a NOAEC. 
17 

6.2 Degradates 

There are no toxicity data available for any of the seven major degradates of zoxamide (i.e., RH24549, RH-127450, RH-129151, RH-139432, RH-141288, RH-150721, and RH-163353). 

Degradates RH-127450, RH-141288, and RH-163353 contain a 3,5-dichloro-4-methylbenzamide 

core structure similar to parent zoxamide (Table 6-2), and degradate RH-129151 is expected to 

be interconvertible with a chemical that contains a 3,5-dichloro-4-methylbenzamide core 

structure. In contrast, RH-150721, RH-139432, and RH-24549 are not structurally similar to 

parent zoxamide (see Table 6-2). EPI Suite: ECOSAR analyses indicate that degradates RH127450 and RH-141288 may be equally or only slightly less toxic (e.g., <10x) to aquatic 

organisms than zoxamide (Table 6-2). Therefore, in the absence of toxicity data for the 

degradates, the stressors of concern for aquatic organisms are zoxamide and degradates RH127450, RH-129151, RH-141288, and RH-163353, and a conservative method of considering 

the stressors of concern in total, i.e., total toxic residue (TTR) approach, will be used. It should 

be noted that in the 2013 ecological risk assessment in support of a Section 3 registration request 

for use on onions (dry bulb), garlic, and shallots (DP 411544), parent zoxamide and degradates 

RH-150721, RH-141288, RH-127450, and RH-163353 were included in the TTR of zoxamide. 

However, a further review of the degradate structures and results of EPI Suite: ECOSAR 

modeling during the problem formulation stage of Registration Review indicated that RH129151 should be added to the TTR of zoxamide and that RH-150721 should be excluded from 

the TTR of zoxamide. 
18 

Table 6-2. Results of EPI Suite: ECOSAR Modeling for Zoxamide and Its Major Degradates 

Chemical Structure Taxon 

Observed 

EPI Suite: ECOSAR Class 

Amides Halo Ketones Halo Benzamides Aliphatic Amines Esters Neutral Organics a-b Ketone Alcohols 

Acute/Chronic Endpoints (mg/L) 

Zoxamide 

Fish 0.156/ 0.00035 0.6/ 0.004 0.01/ 0.004 2.02/ 0.107 

Daphnid >0.780/ 0.039 0.761/ 0.01 0.702/ 0.015 Green algae 

0.01 0.164/ 

0.562 

0.206/ 

0.041 

RH-127450 

Fish 0.855/ 0.005 2.73/ 0.15 

Daphnid 0.993/ 0.013 Green algae 

0.173/ 

0.505 

RH-141288 

Fish 2.44/ 0.014 6.91/ 0.412 5.3/ 0.22 

Daphnid 2.35/ 0.031 7.08/ 0.967 Green algae 

0.259/ 

0.532 

11.1/ 

3.86 

RH-163353 

Fish 23.59/ 0.139 51.35/ 3.66 

Daphnid 14.87/ 0.196 Green algae 

0.592/ 

0.555 

RH-129151 

Fish 0.749/ 1.04 

Daphnid 0.792/ 0.094 Green algae 

0.642/ 

0.116 

RH-150721 

Fish 4.95/ 0.099 4.32/ 2.50 

Daphnid 0.717/ 0.025 45.1/ 0.255 Green algae 

0.543/ 

0.135 

7.09/ 

2.85 
19 

Chemical Structure Taxon 

Observed 

EPI Suite: ECOSAR Class 

Amides Halo Ketones Halo Benzamides Aliphatic Amines Esters Neutral Organics a-b Ketone Alcohols 

Acute/Chronic Endpoints (mg/L) 

RH-139432 

Fish 9.23/ 0.055 21.19/ 1.46 

Daphnid 6.34/ 0.084 Green algae 

0.31/ 

0.341 

RH-24549 

Fish 49.4/ 5.77 

Daphnid 35.9/ 5.45 Green algae 

35.8/ 

18.2 
20 

6.3 Ecological Incidents 

The ecological incident information system (EIIS) is an OPP database that houses ecological 

incidents that have been reported to the Agency. When available, EIIS includes date and 

location of an incident, type and magnitude of effects observed in various species, use(s) of 

pesticides known or suspected of contributing to the incident, and results of any chemical residue 

analysis or other analyses conducted during incident investigation. EIIS incidents are 

categorized according to the certainty that the incident resulted from pesticide exposure. The 

Avian Monitoring System (AIMS) is a database administered by the American Bird Conservancy 

that contains publicly available data on reported avian incidents involving pesticides. Many of 

the incidents listed in this database are also in the EIIS. 

Reviews of the EIIS (version 2.1.1) and AIMS on March 5, 2014 did not yield any reported 

ecological incidents associated with the use of zoxamide. 

In addition to the incidents recorded in EIIS and AIMS, additional incidents are reported to the 

Agency in aggregated form. Pesticide registrants report certain types of incidents to the Agency 

as aggregate counts of incidents occurring per product per quarter. Ecological incidents reported 

in aggregate reports include those categorized as ‘minor fish and wildlife’, ‘minor plant’, and 

‘other non-target’ incidents. ‘Other non-target’ incidents include reports of adverse effects to 

insects and other terrestrial invertebrates. For zoxamide, registrants have not reported any minor 

incidents as of March 5, 2014. 

The total number of actual incidents associated with the use of zoxamide may be higher than 

what is reported to the Agency. Incidents may go unreported since effects may not be 

immediately apparent and/or readily attributed to the use of a chemical. Therefore, a lack of 

reported incidents should not be taken as an indicator of little or no ecological risk. 

 

7 Exposure Pathways of Concern 

The environmental fate properties and use patterns of zoxamide indicate that direct spray, spray 

drift, leaching to ground water, and runoff represent potential transport mechanisms of zoxamide 

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 and were 

found to be exposure pathways of low concern (no LOC exceedances are expected; see 

Appendix D). SIP and STIR are described in detail at: 

http://www.epa.gov/oppefed1/models/terrestrial/index.htm. 

8 Analysis Plan 

8.1 Stressors of Concern 

8.1.1 Ecological Risk Assessment 
21 

The stressors of concern for aquatic organisms are zoxamide and degradates RH-127450, RH129151, RH-141288, and RH-163353. These degradates are considered stressors of concern 

based on the results of EPI Suite: ECOSAR toxicity modeling and/or their structural similarity to 

zoxamide (Table 6-2). 

The stressor of ecological concern for terrestrial organisms is zoxamide. 

8.1.2 Drinking Water Exposure Assessment 

A new drinking water assessment may be conducted, if warranted, to support future human 

health dietary risk assessments of zoxamide for all currently registered uses. The drinking 

assessments of zoxamide incorporate zoxamide residues of concern (i.e., RH-150721, RH24549, RH-141288, RH-129151 and RH-139432) as recommended by the Metabolism 

Assessment Review Committee (MARC) of the Health Effects Division (DP 270797) in surface 

and ground waters. The zoxamide residues of concern may be reevaluated pending receipt and 

review of additional environmental fate and toxicity data for zoxamide and its degradates. 

8.2 Measures of 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. 

A TTR approach will be used to estimate exposure to aquatic organisms. Degradates RH127450, RH-129151, RH-141288, and RH-163353 will be included in the TTR of zoxamide 

based on the results of EPI Suite: ECOSAR toxicity modeling and/or their structural similarity to 

zoxamide (Table 6-2). 

8.2.1 Available Monitoring Data 

The Agency is aware of monitoring conducted by federal and state agencies and this route of 

exposure will be considered in the assessment to the extent that data on zoxamide are available. 

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 conducting the risk assessment will also be considered. The open literature studies are 

identified using EPA’s ECOTOXicology database (ECOTOX)2

 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. 

 

2 http://cfpub.epa.gov/ecotox/
22 

9 Endangered Species Assessments 

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

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

registered uses of zoxamide during 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 Disruptors Screening Program 

Zoxamide was not included in the first group of 67 chemicals for which an order was issued 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 Environmental Fate 

Table 11-1 identifies environmental fate studies that offer data for each guideline requirement 

and whether or not further data are needed in order to support risk assessment. There are no 

environmental fate studies available for any of the major degradates of zoxamide (i.e., RH150721, RH-24549, RH-141288, RH-129151, RH-139432, RH-127450, and RH-163353). In the 

absence of environmental fate data for these degradates, a TTR approach will be used to estimate 

exposure to aquatic organisms. Degradates RH-127450, RH-129151, RH-141288, and RH163353 will be included in the TTR of zoxamide based on their structural similarity to zoxamide 

and results of EPI Suite modeling. The EPI (Estimation Programs Interface) SuiteTM is a 

Windows®-based suite of physical/chemical property and environmental fate estimation 

programs developed by the EPA’s Office of Pollution Prevention Toxics and Syracuse Research 

Corporation (SRC). Additional environmental fate and physicochemical properties of major 

degradates can reduce the uncertainties in the aquatic exposure and drinking water assessments. 

Table 11-1. Submitted Environmental Fate Data for Zoxamide 

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classification 

Are data 

needed to 

conduct risk 

assessment? 

Justification and Assumptions 

EPA will Make in Absence of Data 

835.2120 Hydrolysis 44731909 Acceptable No -- 

835.2240 Aqueous 

photolysis 

44731911 Acceptable No -- 

835.2410 Soil photolysis 44731910 Acceptable No -- 
23 

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classification 

Are data 

needed to 

conduct risk 

assessment? 

Justification and Assumptions 

EPA will Make in Absence of Data 

835.4100 Aerobic soil 

metabolism 

44731912 

44731913 

Acceptable 

Acceptable 

Yes 

Partially 

fulfilled 

OCSPP guidance recommends that 

these tests be performed with four 

soils. Two aerobic soil metabolism 

studies have already been submitted 

and classified as acceptable for risk 

assessment. An additional two 

studies are required under 40 CFR 

Part 158 for terrestrial outdoor uses. 

Because OCSPP uses an upper 90th

percentile estimate of soil 

metabolism half-lives based on 

available study data for modeling 

purposes, any additional data can 

reduce uncertainty related to the 

exposure assessment as well as the 

half-life value used in modeling. 

835.4200 Anaerobic soil 

metabolism 

44731914 Acceptable No 

Partially 

fulfilled 

OCSPP guidance recommends that 

these tests be performed with four 

soils. One anaerobic soil metabolism 

study has already been submitted 

and is classified as acceptable for 

risk assessment. Additional data are 

required under 40 CFR Part 158 for 

terrestrial outdoor uses. Additional 

data are considered to have a low 

potential to add value to exposure 

assessments for the ecological risk 

and drinking water in presence of 

anaerobic aquatic metabolism 

(835.4400). 

835.4300 Aerobic aquatic 

metabolism 

44770002 Acceptable No -- 

835.4400 Anaerobic 

aquatic 

metabolism 

No data NA Yes Data are required under 40 CFR Part 

158. OCSPP guidance recommends 

that these tests be performed with 

two sediments. The assumption of 

compound stability will be made in 

the absence of acceptable data. 

835.1230 

835.1240 

Adsorption/ 

desorption and 

leaching 

44731916 Acceptable No -- 

835.1410 Volatility – 

laboratory 

No data NA No Zoxamide is not expected to be 

volatile under normal use conditions 

based on low vapor pressure and 

Henry’s Law Constant 

835.6100 Terrestrial field 

dissipation 

44732126 Supplemental No --- 

44732127 Supplemental 
24 

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classification 

Are data 

needed to 

conduct risk 

assessment? 

Justification and Assumptions 

EPA will Make in Absence of Data 

850-6100 Analytical 

method in soil 

44731906 Supplemental No --- 

Analytical 

method in water 

44731908 Supplemental 

165-4 

(850.1730) 

Fish 

bioconcentration 

4731932 Acceptable No --- 

NA = not applicable 

11.2 Ecological Effects 

Tables 11-2 and 11-3 identify ecological effects studies that offer data for each guideline 

requirement and whether or not further data are needed in order to support risk assessment. 

There are no ecological effects studies available for any of the major degradates of zoxamide 

(i.e., RH-150721, RH-24549, RH-141288, RH-129151, RH-139432, RH-127450, and RH163353). In the absence of toxicity data for these degradates, the stressors of concern for aquatic 

organisms are zoxamide and degradates RH-127450, RH-129151, RH-141288, and RH-163353, 

and a conservative method of considering the stressors of concern in total, i.e., the total toxic 

residue (TTR) approach, will be used. 
25 

Table 11-2. Submitted Aquatic Ecological Effects Data for Zoxamide 

OCSPP Guideline 

Data Requirement 

Source MRID 

Classification Are Data 

Needed to Conduct the Risk Assessment? 

Justification and Assumptions EPA Will Make in th

 850.1010 Freshwater 

invertebrate acute toxicity 

44731920 Acceptable No -- 

850.1025 850.1035 850.1045 850.1055 

Saltwater invertebrate acute toxicity 

 44731924 (mollusk) 

Acceptable No -- 

44731923 (mysid) 

Acceptable 

 850.1075 Freshwater fish 

acute toxicity 

44731926 (cold water) 

Acceptable No -- 

44731931 (warm water) 

Acceptable 

44731927 (warm water) 

Acceptable 

 850.1075 Saltwater fish 

acute toxicity 

44731928 Acceptable No -- 

 850.1300 Freshwater 

invertebrate life cycle 

44731921 Acceptable No -- 

 850.1350 Saltwater 

invertebrates life cycle 

44731925 Acceptable No -- 

 850.1400 Freshwater fish 

early-life stage 

44731929 Acceptable No -- 

 850.1400 Saltwater fish 

early-life stage 

44731930 Acceptable No -- 

850.1500 Fish life cycle, 

freshwater 

44731931 Acceptable No 

850.1735 850.1740 

Whole sediment: acute invertebrates freshwater and marine 

No data NA Yes Acute sediment invertebrate toxicity data are required 

i. the half-life of the pesticide in sediment if ≤ 10 da

or aquatic metabolism studies and if any of the folA. The soil partition coefficient (Kd) is ≥ 50 B. The log Kow is ≥ 3. C. The Koc is ≥ 1,000. 
26 

OCSPP Guideline 

Data Requirement 

Source MRID 

Classification Are Data 

Needed to Conduct the Risk Assessment? 

Justification and Assumptions EPA Will Make in thThe half-life of zoxamide in aerobic aquatic metabolisto 7.6 days; the log Kow of zoxamide is 3.76; and zoxaand sandy loam are all ≥ 1196. 

Acute sediment tests with the midge Chironomus dilutHyalella azteca, and/or estuarine/marine amphipod Lepneeded. In the absence of these data, sediment-dwelling invertesurrogate pesticides – starting with data for closely relaproceeding to data for less related pesticides – may be chronic toxicity of zoxamide to sediment-dwelling inv

850.4400 Aquatic plant 

toxicity test using Lemna

spp. 

44731945 Acceptable No -- 

850.4500 Algal toxicity 44731938 

44731939 (green alga) 

Acceptable Supplemental 

No -- 

44731942 (marine diatom) 

Acceptable 

44770005  (freshwater diatom) 

Acceptable 

850.4550 Cyanobacteria 

toxicity 

44731940 Acceptable No -- 

NA = not applicable 
27 

Table 11-3. Submitted Terrestrial Ecological Effects Data for Zoxamide

OCSPP Guideline 

Data Requirement 

Source MRID 

Classification Are Data 

Needed to Conduct the Risk Assessment?

Justification and Assumptions EPA Will Make in th

 850.2100 Avian oral 

toxicity 

44731933 (upland game) 

Acceptable No Acute oral toxicity data for a passerine species are requ

CFR Part 158. A study has not been submitted for this A guideline-compliant passerine acute oral toxicity tes

toxicity data are only available for one avian species (iPasserine birds may utilize metabolic pathways that ar

birds and therefore be more sensitive to zoxamide. Fuexhibit behavioral responses to pesticide dosing that arreduced fitness in the field (e.g., regurgitation of conta

direct biochemically-mediated lethal toxicity is not appIn the absence of these data, passerine toxicity data for starting with data for closely related pesticides and prorelated pesticides – may be used to characterize the acuto passerine species.

No data (passerine) 

NA Yes 

 850.2200 Avian dietary 

toxicity 

44731934  (upland game) 

Acceptable No -- 

44731935 (waterfowl) 

Acceptable 

 850.2300 Avian 

reproduction 

44731936 (upland game) 

Acceptable No -- 

44947401 (waterfowl) 

Acceptable 

 850.3020 Honey bee acute 

contact toxicity 

44731919 Acceptable No -- 

Nonguideline Honey bee acute oral toxicity 44950504 Acceptable No 
28 

OCSPP Guideline 

Data Requirement 

Source MRID 

Classification Are Data 

Needed to Conduct the Risk Assessment?

Justification and Assumptions EPA Will Make in th

Nonguideline Larval honey bee acute oral 

toxicity 

No data NA Yes The “White Paper in Support of the Proposed Risk Ass

Bees” as submitted to the FIFRA Scientific Advisory P

screening-level risk assessment process that includes atoxicity tests with adult bees and an acute oral toxicity Larval honey bee acute oral toxicity data are not availaIn the absence of these data, larval honey bee oral toxipesticides – starting with data for closely related pesticdata for less related pesticides – may be used to characzoxamide to honey bees. 

850.4100 Seedling 

Emergence and 

Seedling Growth 

49183404 Supplemental Yes Acceptable data are not available. The submitted study 

“supplemental” because a definitive NOAEC (i.e., NO

zoxamide/A) could not be determined for corn, and theryegrass dry weight. For corn, a study that defines a Nconcentration that is not statistically different from the assessed endpoints) is recommended. For ryegrass, a Temergence test is recommended. 

850.4150 Vegetative 

Vigor 

49183405 Acceptable No -- 

NA = not applicable3 http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2012-0543-0004
29 

12 References 

DP 266174 and 254295. Section 3 Registration Request for Uses of Zoxamide. January 3, 2001. 

DP 270797. PP#9F05058; Zoxamide in/on Potato and Grapes. Conclusions of the 11/14/2000 

Meeting of the Metabolism Assessment Review Committee. 

DP 411544. Zoxamide: Ecological Risk Assessment to Support the Proposed New Uses on 

Onions (Dry Bulb), Garlic, and Shallots. December 23, 2013. 

DP 417061. Drinking Water Exposure Assessment in Support of the New Use Registration of 

Zoxamide Formulated Product Gavel® 75DF on Onions (Dry Bulb), Garlic and Shallots. 

January 17, 2014. 

FAO 2000. Food and Agriculture Organization of the United Nations. FAO PESTICIDE 

DISPOSAL SERIES 8. Assessing Soil Contamination: A Reference Manual. Appendix 2. 

Parameters of pesticides that influence processes in the soil. Editorial Group, FAO 

Information Division: Rome, 2000. 

http://www.fao.org/DOCREP/003/X2570E/X2570E00.htm

Cited Environmental Fate Studies 

44731802 Kemmerer, S.; Roemmele, R. (1998) Product Chemistry Series 830 Group A, 

Guideline Numbers OPPTS: 830.1550, 830.1600, 830.1620, 830.1670, 830.1700, 

830.1750, 830.1800: Product Identity, Composition, and Analysis for RH117,281 Technical: Lab Project Number: APR-98-282: TM-98-212-02: APR-98-

277. Unpublished study prepared by Rohm and Haas Company and Lancaster 

Laboratories. 481 p. 

44731906 Szuter, S.; Guo, I. (1998) Independent Laboratory Method Validation Trials RH117,281 Analytical Method Soil (TR 34-98-126): Lab Project Number: 1401.15: 

34-98-160: TR 34-98-126. Unpublished study prepared by Mckenzie 

Laboratories, Inc. 101 p. {OPPTS 850.7100} 

44731907 Vlkel, W. (1998) Analytical Method for the Determination of RH-117281 in 

Drinking Water: Lab Project Number: 1401.36: 692256: 34P-98-24. Unpublished 

study prepared by RCC, Ltd. 35 p. 

44731908 Reynolds, J. (1998) Hydrolysis of (carbon-14) RH-117281 in Water at pH 4, 7, 

and 9: Lab Project Number: XBL95006: RPT00251: 34P-95-20. Unpublished 

study prepared by Xenobiotic Laboratories, Inc. 349 p. 

44731910 Reynolds, J. (1997) Soil Photolysis of (carbon-14)RH-117281: Lab Project 

Number: 95009: RPT00261: 34-P-95-74. Unpublished study prepared by Agvise 

Laboratories and Xenobiotic Laboratories, Inc. 138 p. 
30 

44731911 Reynolds, J.; Smalley, J. (1998) Aqueous Photolysis of (carbon-14)RH-117281: 

Lab Project Number: XBL95008: RPT00259: 34-96-215. Unpublished study 

prepared by Xenobiotic Laboratories, Inc. 146 p. 

44731912 Reynolds, J.; Smalley, J. (1997) Aerobic Soil Metabolism of (carbon-14)RH117281 Fungicide: Lab Project Number: XBL95003: RPT00256: 34P-95-10. 

Unpublished study prepared by Xenobiotic Laboratories, Inc. 193 p. 

44731913 Carbone, J. (1998) Deviation of Degradation Kinetics of RH-117,281 Technical 

Fungicide for PRZM3.12 Modeling Further Analysis of Data from Aerobic Soil 

Metabolism of (carbon-14)-RH-117,281 Fungicide: Lab Project Number: 98R1101. Unpublished study prepared by Rohm and Haas Company. 24 p. 

44731914 Kang, H. (1997) Anaerobic Soil Metabolism of (carbon-14)RH-117281: Lab 

Project Number: XBL95010: RPT00267: 34P-95-75. Unpublished study prepared 

by Rohm and Haas Company and XenoBiotic Laboratories, Inc. 123 p. 

44731916 Shelby, D. (1996) Adsorption and Desorption of RH-117,281 to Soil: Lab Project 

Number: 6627-95-0224-EF-001: 95-0024: TR34-96-01. Unpublished study 

prepared by Ricerca, Inc. 105 p. 

44732126 Vaughn, F. (1998) Dissipation of RH-7281 on Soil in Canada: Lab Project 

Number: 97RHC01: 97RHC01-A: 98RHC33.REP. Unpublished study prepared 

by Enviro-Quest, and Vaughn Agricultural Research Services, Ltd. 262 p. 

44732127 Ross, J. (1998) Terrestrial Field Dissipation of RH-117,281 on Bare Soil in 

California and New York: Lab Project Number: 34P-96-30: 34P-96-30A: 34P-96-

30-B. Unpublished study prepared by Grayson Research LLC, and Rohm and 

Haas Company. 658 p. 

44731932 Robinson, R. (1998) RH-117,281: Uptake, Depuration, Bioconcentration and 

Metabolism of (carbon-14)-RH-117,281 in Bluegill Sunfish Under Flow Through 

Test Conditions: Lab Project Number: XBL96025: RPT00328: 34P-96-26. 

Unpublished study prepared by Xenobiotic Laboratories, Inc. and ABC 

Laboratories, Inc. 345 p. 

44770002 Morgenroth, U. (1998) (Carbon-14)-RH-117281: Degradation and Metabolism in 

Aquatic Systems: Lab Project Number: TR34-98-47: 624510: 34P-96-42. 

Unpublished study prepared by RCC Ltd. 121 p. 

Cited Ecological Effects Studies 

44731919 Kirkland, R. (1993) Acute Contact Toxicity of RH-117,281 Technical to Honey 

Bees: Lab Project Number: BIO 109-93: 92RC-0235. Unpublished study prepared 

by Rohm and Haas Company and Bio Research. 55 p. 

44731920 Sword, M. (1995) Acute Flow-Through Toxicity of RH-117,281 Technical to 

Daphnia magna: Lab Project Number: 94RC-0081: 41683: 94P-081. Unpublished 

study prepared by ABC Laboratories, Inc. 268 p. 
31 

44731921 Stewart, S.; Murrell, H.; Rhodes, J. (1997) Chronic Toxicity of RH-117,281 

Technical to Daphnia magna Under Flow-Through Test Conditions: Lab Project 

Number: 43209: 95RC-0273. Unpublished study prepared by ABC Laboratories, 

Inc. 79 p. 

44731922 Van der Kolk, J. (1998) RH-117,281: Chronic Effects on Midge Larvae 

(Chironomus riparius) in a Water/Sediment System: Final Report: Lab Project 

Number: 97RC-0083: 97-063-1007: 1007.027.173. Unpublished study prepared by 

Springborn Laboratories. 85 p. 

44731923 Roberts, C.; Swigert, J. (1997) RH-117,281 Technical: A 96-Hour Flow-Through 

Acute Toxicity Test with the Saltwater Mysid (Mysidopsis bahia): Final Report: 

Lab Project Number: 129A-136: 95RC-0275: SDR23. Unpublished study prepared 

by Wildlife International Ltd. 89 p. 

44731924 Roberts, C.; Swigert, J. (1997) RH-117,281 Technical: A 96-Hour Shell Deposition 

Test with the Eastern Oyster (Crassostrea virginica): Final Report: Lab Project 

Number: SDR23: 129A-137: 95RC-0276. Unpublished study prepared by Wildlife 

International Ltd. 93 p. 

44731925 Drottar, K.; Krueger, H. (1998) RH-117,281 Technical: A Flow- Through LifeCycle Toxicity Test with the Saltwater Mysid (Mysidopsis bahia): Final Report: 

Lab Project Number: 1294-142: 97RC-0077. Unpublished study prepared by 

Wildlife International Ltd. 152 p. 

44731926 Sword, M.; Gardner, C. (1995) Acute Flow-Through Toxicity of RH-117,281 

Technical to Rainbow Trout (Oncorhynchus mykiss): Final Report: Lab Project 

Number: 94RC0078: 41681. Unpublished study prepared by ABC Laboratories, 

Inc. 254 p. 

44731927 Sword, M.; Gardner, C. (1995) Acute Flow-Through Toxicity of RH-117,281 

Technical to Bluegill (Lepomis macrochirus): Final Report: Lab Project Number: 

94RC-0080: 41682. Unpublished study prepared by ABC Laboratories, Inc. 227 p. 

44731928 Roberts, C.; Swigert, J. (1997) RH-117,281 Technical: A 96-Hour Flow-Through 

Acute Toxicity Test with the Sheepshead Minnow (Cyprinodon Variegatus): Final 

Report: Lab Project Number: 129A-135: 95RC-0274. Unpublished study prepared 

by Wildlife International, Ltd. 90 p. 

44731929 Downing, J.; Leak, T.; Stewart, S. (1996) Early Life-Stage of RH-117281 

Technical to the Rainbow Trout (Oncorhynchus mykiss) Under Flow-Through 

Conditions: Lab Project Number: 42400: 94RC-0239. Unpublished study prepared 

by ABC Laboratories, Inc. 490 p. 

44731930 Drottar, K.; Krueger, H. (1998) RH-117,281 Technical: An Early Life-Stage 

Toxicity Test with the Sheepshead Minnow (Cyprinodon variegatus): Final Report: 

Lab Project Number: 129A-143A: 97RC-0078. Unpublished study prepared by 

Wildlife International, Ltd. 142 p. 
32 

44731931 Drottar, K.; Krueger, H. (1998) RH-117,281 Technical: A Flow-Through LifeCycle Toxicity Test with the Fathead Minnow (Pimephales promelas): Final 

Report: Lab Project Number: 129A-141: 97RC-0079. Unpublished study prepared 

by Wildlife International, Ltd. 188 p. 

44731933 Williams, B. (1997) RH-117,281 Technical: 14-Day Acute Oral LD50 Study in 

Bobwhite Quail: Lab Project Number: RH117BWLD-595: 94RC-0240. 

Unpublished study prepared by Ecological Planning and Toxicology, Inc. 44 p. 

44731934 Williams, B. (1997) RH-117,281 Technical: 8-Day Acute Dietary LC50 Study in 

Bobwhite Quail: Lab Project Number: RH117BWLC-395: 94RC-0242. 

Unpublished study prepared by Ecological Planning and Toxicology, Inc. 94 p. 

44731935 Williams, B. (1997) RH-117,281 Technical: 8-Day Acute Dietary LC50 Study in 

Mallard Ducklings: Lab Project Number: RH117MDLC-395: 94RC-0241. 

Unpublished study prepared by Ecological Planning and Toxicology, Inc. 94 p. 

44731936 Kapustka, L. (1998) Avian Reproduction Study of RH-117,281 Technical with 

Northern Bobwhite: Lab Project Number: 97RC-0081: RH7281BW-97-2. 

Unpublished study prepared by Ecological Planning and Toxicology, Inc. 288 p. 

44731938 Ziegler, T.; Stewart, S. (1996) Acute Toxicity of RH-117,281 Technical to 

Selenastrum capricornutum Printz: Lab Project Number: 42399: 94RC-0238. 

Unpublished study prepared by ABC Laboratories, Inc. 438 p. 

44731939 Drottar, K.; Sutherland, C.; Krueger, H. (1998) RH-117,281 Technical: A 96-Hour 

Toxicity Test with the Freshwater Alga (Scenedesmus subspicatus): Lab Project 

Number: 129A-151: 97RC-0133. Unpublished study prepared by Wildlife 

International Ltd. 91 p. {OPPTS 850.5400} 

44731940 Drottar, K.; Sutherland, C.; Krueger, H. (1998) RH-117,281 Technical: A 96-Hour 

Toxicity Test with the Freshwater Alga (Anabaena flos-aquae): Lab Project 

Number: 129A-154: 97RC-0130. Unpublished study prepared by Wildlife 

International Ltd. 85 p. 

44731942 Drottar, K.; Krueger, H. (1998) RH-117,281 Technical: A 96-Hour Toxicity Test 

with the Marine Diatom (Skeletonema costatum): Final Report: Lab Project 

Number: 129A-152: 97RC-0132. Unpublished study prepared by Wildlife 

International Ltd. 84 p. {OPPTS 850.5400} 

44731945 Drottar, K.; Krueger, H. (1998) RH-117,281 Technical: A 14-Day Static-Renewal 

Toxicity Test with Duckweed (Lemna gibba G3): Final Report: Lab Project 

Number: 129A-147: 97RC-0080. Unpublished study prepared by Wildlife 

International Ltd. 86 p. {OPPTS 850.4400} 

44770003 Downing, J.; Leak, T. (1995) RH-117, 281 Technical: Toxicity to the Earthworm, 

Eisenia foetida: Lab Project Number: 94RC-0237: 42398-6. Unpublished study 

prepared by ABC Laboratories, Inc. 256 p. 

44770005 Drottar, K.; Sutherland, C.; Krueger, H. (1998) RH-117, 281 Technical: A 96-Hour 

Toxicity Test with the Freshwater Diatom (Navicula pelliculosa): Final Report: Lab 
33 

Project Number: 97RC-0131: 129A-153: C.3. Unpublished study prepared by 

Wildlife International Ltd. 89 p. {OPPTS 850.5400} 

44947401 Gallagher, S.; Beavers, J.; Martin, K. et al. (1999) RH-117,281 Technical: A 

Reproduction Study with the Mallard (Anas platyrhynchos): Lab Project Number: 

98RC-0166: 129-164. Unpublished study prepared by Rohm and Haas Company. 

220 p. 

44950501 Ward, C.; Murdock, C. (1998) Toxicity of Dithane/RH-117,281 DG Blend to 

Selenastrum capricornutum Printz: Lab Project Number: 44178: 97RC-0069. 

Unpublished study prepared by ABC Laboratories, Inc. 181 p. 

44950502 Madsen, T.; Leak, T. (1998) Acute Toxicity of Dithane/RH-117,281 DG Blend to 

Daphnia magna: Lab Project Number: 44179-97: 97RC-0068. Unpublished study 

prepared by ABC Laboratories, Inc. 79 p. 

44950503 Rhodes, J.; Bucksath, J. (1998) Acute Flow-Through Toxicity of Dithane/RH117,281 DG Blend to Rainbow Trout (Oncorhynchus mykiss): Lab Project Number: 

43357: 97RC-0128: 95P-278. Unpublished study prepared by ABC Laboratories, 

Inc. 110 p. 

44950504 Milligan, D. (1997) Dithane/RH-117,281 DG Blend (8:1): Laboratory Oral and 

Contact Test with the Honeybee, Apis mellifera: Final Report: Lab Project Number: 

97-071-1007: 97RC-0070: 1007.030.265. Unpublished study prepared by 

Springborn Laboratories AG. 48 p. 

46056401 Dickson, J.; Knight, B. (1998) Dithane/RH-7281 80 EP (10:1): Determination of 

Acute Toxicity (LC50) to Rainbow Trout (96h, Continuous Flow). Project Number: 

16697, 97RC/0214, 392008. Unpublished study prepared by Inveresk Research. 42 

p. 

46056403 Rhodes, J. (1999) Acute Toxicity of Dithane/RH-7281 (11.2:1) DG Blend to the 

Green Alga, Selenastrum capricornutum. Project Number: 45118, 98RC/0238. 

Unpublished study prepared by Analytical Bio-Chemistry Labs., Inc. 156 p. 

46096901 Buchanan, J.; Knight, B.; Dickson, J. (1998) Dithane/RH-7281 80WP (10:1): 

Determination of Acute Toxicity (EC50) to Daphnia (48h, Continuous Flow). 

Project Number: 16564, 97RC/0215, 392029. Unpublished study prepared by 

Inveresk Research International. 42 p. 

49183404 Sindermann AB, Porch JR, Krueger HO, Martin KH and R VanHoven. 2012. Gavel 

(Mancozeb 66.7%, Zoxamide 8.3%): A Tier I toxicity test to determine the effects 

of the test substance on seedling emergence of ten species of plants. Unpublished 

study performed by Wildlife International, Ltd., Easton, Maryland. Laboratory 

project no.: 334-126. Study sponsored by Gowan Company, Yuma, Arizona. Study 

initiated July 11, 2011 and completed January 19, 2012. 

49183405 Sindermann AB, Porch JR, Krueger HO, Martin KH and R VanHoven. 2011. Gavel 

(Mancozeb 66.7%, Zoxamide 8.3%): A Tier I toxicity test to determine the effects 

of the test substance on vegetative vigor of ten species of plants. Unpublished study 
34 

performed by Wildlife International, Ltd., Easton, Maryland. Laboratory project 

no.: 334-127. Study sponsored by Gowan Company, Yuma, Arizona. Study 

initiated July 11, 2011 and completed December 12, 2011. 
35 

Appendix A: Summary of Zoxamide Labels 

Crop EPA 

Reg # 

Product Name 

Max. 

Single 

App. 

Rate 

(lb a.i./A) 

Max. # 

App./ 

Crop 

Cycle 

Max. 

Seasonal 

App. 

Rate/ 

Crop 

Cycle 

(lb a.i./A) 

Min. 

App. 

Interval 

(days) 

App. Timing 

Application Equipment/ Type 

DisalloGeogrAreas 

Cucurbit vegetables Grapes Tomato 

10163-6413 

Zoxium 80W Agricultural Fungicide 

0.2 8 1.6 7 Foliar 

Sprinkler irrigation/ chemigation Aircraft/spray Ground/spray Hand held sprayer/spray 

Potato, white/Irish 

10163-6413 

Zoxium 80W Agricultural Fungicide 

0.2 8 1.6 5 Foliar 

Sprinkler irrigation/ chemigation Aircraft/spray Ground/spray Hand held sprayer/spray 

Grapes 10163- 6414 Gavel 75 DF 0.2075 3 0.6225 7 

Bloom, pre-bloom Aircraft/broadcast 

Ground/broadcast 

Post-bloom CA Bloom, post-bloom, pre-bloom 

Sprinkler system/chemigation 

Grapes 10163- 6414 Gavel 75 DF 0.2075 6 10.245 7 

Bloom, pre-bloom Aircraft/spray 

Ground/spray 

Post-bloom CA 

Potato, white/irish 

10163-6414 Gavel 75 DF 0.166 6 0.996 5 Foliar 

Aircraft/broadcast Ground/broadcast 
36 

Crop EPA 

Reg # 

Product Name 

Max. 

Single 

App. 

Rate 

(lb a.i./A) 

Max. # 

App./ 

Crop 

Cycle 

Max. 

Seasonal 

App. 

Rate/ 

Crop 

Cycle 

(lb a.i./A) 

Min. 

App. 

Interval 

(days) 

App. Timing 

Application Equipment/ Type 

DisalloGeogrAreas 

Sprinkler irrigation/ chemigation 

DE, MNY, MMA, OCT, NVT 

Aircraft/spray 

OH, NFL, CTME, MPA, NMA 

Ground/spray 

DE, MNY, POH, FRI, MAWI 

Tomato 10163- 6414 Gavel 75 DF 0.166 4 0.664 7 Foliar 

Aircraft/broadcast Ground/broadcast Sprinkler system/chemigation 

Tomato 10163- 6414 Gavel 75 DF 0.166 8 1.328 7 Foliar 

Sprinkler irrigation/ chemigation Aircraft/spray Ground/spray 
37 

Appendix B: Environmental Transformation Products of Zoxamide 

Table B-1. Environmental Transformation Products of Zoxamide 

Code Name/ 

Synonym 

Chemical Name/ 

Smiles Code Chemical Structure 

Study Type/ 

Corresponding OCSPP 

Guideline 

MRID 

Major (>10%) Transformation Products 

RH-150721 

(3-amino-3-methyl-2-oxo)pentyl-(3,5-dichloro4-methyl) benzoate c1c(cc(c(c1CL)C)CL)C(=O)OCC(=O)(C(C)(CC)N) 

Hydrolysis @pH 4 835.2130 4473190Aquatic Photolysis 835.2240 4473191

RH-24549 

3,5-dichloro-4-methylbenzoic acid c1c(cc(c(c1CL)C)CL)C(=O)O 

Hydrolysis @pH 4 835.2130 4473190

Aquatic Photolysis 835.2240 4473191Soil Photolysis 835.2410 4473191Anaerobic Soil Metabolism 835.4200 

4431912 4431913 

RH-141288 

3,5-dichloro-N-(3-hydroxy-1-ethyl-1-methyl--2-oxopropyl)-4-methylbenzamide c1c(cc(c(c1CL)C)CL)C(=O)(N(C(C(=O)(CO))(C)CC)) 

Hydrolysis @pH 9 835.2130 4473190

RH-129151 

2-(3,5-dichloro-4-methylphenyl)-4-ethyl-4- methyl-4H-1,3-oxazin5(6H)-one c1(c(c(cc(c1)C2=NC(C(=O)(CO2))(C)CC)CL)C)CL 

Hydrolysis @pH 7 835.2130 4473190
38 

Code Name/ 

Synonym 

Chemical Name/ 

Smiles Code Chemical Structure 

Study Type/ 

Corresponding OCSPP 

Guideline 

MRID 

RH-139432 

3,5-dichloro-4-methylbenzamide c1c(cc(c(c1CL)C)CL)C(=O)(N) 

Aquatic Photolysis 835.2240 4473191

RH-127450 

3,5-dichloro-N-(1-ethyl-1-methyl-2- oxopropyl)-4-methylbenzamide c1c(cc(c(c1CL)C)CL)C(=O)(N(C(C(=O)(C))(C)CC)) 

Soil Photolysis 835. 2410 4473191

Aerobic Aquatic Metabolism 835.4300 4477000

RH-163353 

3,5-dichloro-N-(2-carboxy1-ethyl-1-methyl-2- oxoethyl)-4-methylbenzamide c1c(cc(c(c1CL)C)CL)C(=O)(N(C(C(=O)(C(=O)(O)))(C)CC)) 

Aerobic Aquatic Metabolism 835.4300 4477000

-- Carbon Dioxide CO2 Aerobic Soil Metabolism 835.4200 4473191

4473191

-- Bound Residue --- 

Aerobic Soil Metabolism 835.4200 

44731914473191

Anaerobic Soil Metabolism 835.4200 4473191Aerobic Aquatic Metabolism 835.4300 4477000

Minor (<10%) Transformation Products 

Transformation Products 1 to 6 10 to 12 

No Structure and CAS name available 

Soil Photolysis 835. 2410 4473191

 Met 1 No Structure and CAS name available Anaerobic Soil Metabolism 835.4200 4473191 Met 2 No Structure and CAS name available Aerobic Soil Metabolism 835.4200 4473191

4473191
39 

Code Name/ 

Synonym 

Chemical Name/ 

Smiles Code Chemical Structure 

Study Type/ 

Corresponding OCSPP 

Guideline 

MRID 

 Met 4 No Structure and CAS name available Aerobic Soil Metabolism 835.4200 4473191

4473191

 Met 5 No Structure and CAS name available Anaerobic Soil Metabolism 835.4200 4473191 Met 6 No Structure and CAS name available Anaerobic Soil Metabolism 835.4200 4473191 Met 7 No Structure and CAS name available Anaerobic Soil Metabolism 835.4200 4473191 Met 8 No Structure and CAS name available Anaerobic Soil Metabolism 835.4200 44731911Bold font indicates maximum concentration of degradate observed in various environmental fate studies. 2Percent of aggregate of several transformation products 3TLC suggests that Met 4 consisted of between four and six additional transformation products 
40 

Appendix C: Summary of Toxicity Studies with Zoxamide and Zoxamide Co-Formulated with 

Table C-1. Summary of Endpoints from Toxicity Studies with Zoxamide (Synonyms: RH 117,281; RH-14RH- 7281) and Zoxamide Co-Formulated with Mancozeb 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

Avian acute oral: single dose, 14-day observation 

RH-117,281 Technical (92.9) NA 

Bobwhite quail (Colinus virginianus) 

LD50 > 2000 mg a.i./kg-bw (nom) 

NOAEL = 2000 mg a.i./kg-bw (nom) (no mortality or sublethal effects) Practically non-toxic 

Avian sub-acute dietary: 5-day exposure; 3-day post-exposure observation 

RH-117,281 Technical (92.9) 

Mallard duck (Anas platyrhynchos)

LC50 > 5250 mg a.i./kg-diet (nom) 

NOAEC = 2625 mg a.i./kg-diet (nom) LOAEC = 5250 mg a.i./kg-diet (nom) (NOAEC based on 10% mortality at 5250 mg/kg-diet; no subletheffects) Practically non-toxic 

Bobwhite quail (Colinus virginianus) 

LC50 > 5250 mg a.i./kg-diet (nom) 

NOAEC = 5250 mg a.i./kg-diet (nom) (no mortality; wing droop on day 3 at 5250 mg/kg-diet) Practically non-toxic 

Avian reproduction: 22 weeks (chronic) 

RH-117,281 Technical (92.3) 

Bobwhite quail (Colinus virginianus) 

NOAEC = 1000 mg a.i./kg-diet (nom) LOAEC >1000 mg a.i./kg-diet (nom) (no effects) 

Mallard duck (Anas platyrhynchos) 

NOAEC = 1000 mg a.i./kg-diet (nom) LOAEC >1000 mg a.i./kg-diet (nom) (no effects) 

Mammalian acute oral limit: single dose; 14-day observation 

RH-141,455 (98.74) 

Rat (Rattus norvegicus) 

LD50 > 5,000 mg a.i./kg-bw 

NOAEL = not determined (no mortality; scant feces in all males and females on day 1 and 2 females on day 2) Practically non-toxic 

RH-141,452 (97.7) 

Laboratory Mouse (Mus musculus domesticus) 

LD50 > 5,000 mg a.i./kg-bw 

NOAEL = not determined (no treatment-related mortality; scant feces in 1 male on day 1) 
41 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)Practically non-toxic 

Mammalian 2-generation reproduction (chronic) 

RH-117,281 Technical (92.3) 

Rat (Rattus norvegicus) 

Parental, systemic toxicity 

NOAEC = 5,000 mg a.i./kg-diet  (409.3 mg a.i./kg-bw/day) LOAEC = 20,000 mg a.i./kg-diet  (1624.4 mg a.i./kg-bw/day) (based on decreased weights and body weight gains in females oReproductive toxicity NOAEC ≥ 20,000 mg a.i./kg-diet (2091.2/2239.1 [M/F] mg a.i./bw/day) (based on no effects) 

Bee acute contact: single dose, 48-hour observation 

RH-117,281 Technical (>95%) 

Honey bee (Apis mellifera)

LD50 > 100 μg a.i./bee (nom) 

NOAEL = 100 μg a.i./bee (nom) (1-3% mortality across solvent control and 4 treatment concentraPractically non-toxic 

Form.: Dithane/RH7281 DG Blend Mancozeb (69) Zoxamide (8.26) 

Honey bee (Apis mellifera) 

LD50 > 16.52 μg zoxamide /bee#

NOAEL = 16.52 zoxamide/bee#

LD50 > 138 μg mancozeb/bee#

NOAEL = 138 μg mancozeb/bee#

LD50 >200 μg form./bee 

NOAEL = 200 μg form./bee (3% mortality in the solvent control and 0, 30, 0, 10, and 0% moat 12.5, 25, 50, 100, and 200 μg form./bee) Practically non-toxic 

Bee acute oral limit: 72 hours 

Form.: Dithane/RH7281 DG Blend Mancozeb (69) Zoxamide (8.26) 

Honey bee (Apis mellifera) 

LD50 > 12.6 μg zoxamide /bee#

NOAEL = 12.6 μg zoxamide/bee#

LD50 > 106 μg mancozeb/bee#

NOAEL = 106 μg mancozeb/bee#LD50 >153 μg form./bee 

NOAEL = 153 μg form./bee 
42 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)(0 and 23% mortality in the solvent control and 153 μg form./bee treatment groups, respectively) Practically non-toxic 

Soil: 14 days RH-117,281 

Technical (94.2) 

Earthworm (Eisenia foetida) 

LC50 > 1070 mg a.i./kg-soil 

NOAEC = 66.7 mg a.i./kg-soil LOAEC = 134 mg a.i./kg-soil (NOAEC based on 20-35% mortality ≥134 mg/kg-soil compared 5% mortality at 66.7 mg/kg-soil; also lethargy at ≥ 134 mg/kg-so

Terrestrial plant seedling emergence: limit, 21 days 

TEP: Gavel® 

75DF Mancozeb (64) Zoxamide (8.7) 

Most sensitive monocots: Ryegrass and corn 

Corn (based on height) 

EC25 > 1.3 lb zoxamide/A 

NOAEC < 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC < 10.7 lb mancozeb/A Ryegrass (based on dry weight) 

EC25 = ~1.3 lb zoxamide/A 

NOAEC: Not determined EC25 = ~10.7 lb mancozeb/A NOAEC: Not determined 

Most sensitive dicot: None 

EC25 > 1.3 lb zoxamide/A 

NOAEC = 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC = 10.7 lb mancozeb/A Most sensitive parameter: None 

Terrestrial plant vegetative vigor: limit, 21 days 

TEP: Gavel® 

75DF Mancozeb (64) Zoxamide (8.7) 

Most sensitive monocot: None 

EC25 > 1.3 lb zoxamide/A 

NOAEC = 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC = 10.7 lb mancozeb/A Most sensitive parameter: None 
43 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

Most sensitive dicot: None 

EC25 > 1.3 lb zoxamide/A 

NOAEC = 1.3 lb zoxamide/A EC25 > 10.7 lb mancozeb/A NOAEC = 10.7 lb mancozeb/A Most sensitive parameter: None 

Freshwater fish acute: 96 hours, flow-through 

RH-117,281 Technical (94.2) 

Rainbow trout (Oncorhynchus mykiss) 

LC50 (95% C.I.) = 156 (134-181) μg a.i./L (mm) 

Probit slope (95% C.I.) = 6.4 (3.9-8.9) NOAEC = 51 μg a.i./L (mm) LOAEC = 140 μg a.i./L (mm) (NOAEC based on signs of toxicity including quiescence, surfacdark discoloration, labored respiration, and lying on the bottom a

140 μg/L) Highly toxic 

Form.: Dithane/ RH-7281 80 WP Mancozeb (71.00) Zoxamide (7.09) 

Rainbow trout (Oncorhynchus mykiss) 

Preliminary endpoints 

LC50 (95% C.I.) = 10 (8-13) μg zoxamide /L (mm) 

NOAEC = 2 μg zoxamide /L (mm) LOAEC = 6 μg zoxamide /L (mm) LC50 (95% C.I.) = 120 (76-176) μg mancozeb/L (mm) NOAEC = 3 μg mancozeb /L (mm) LOAEC = 6.3 μg mancozeb /L (mm) LC50 (95% C.I.) = 159 (129-232) μg form./L (mm) NOAEC = 87 μg form./L (mm) LOAEC = 92 μg form./L (mm) (NOAEC based on mortality and signs of toxicity including slighcoloration, slight lethargy, and near base of tank at 92 μg form./L

RH-117,281 Technical 

Fathead minnow (Pimephales promelas) 

LC50 > 208 μg a.i./L (mm) 

(no mortality) At most highly toxic 
44 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

RH-117,281 Technical (94.2) 

Bluegill sunfish (Lepomis macrochirus) 

LC50 > 790 μg a.i./L (mm) 

NOAEC: not specified (0, 20, 0, and 20% ≤0.17, 0.29, 0.49, and 0.79 μg/L; signs of toxiincluding quiescence, surfacing, dark discoloration, labored respiration, and lying on the bottom at ≥ 0.17 μg/L; exopthalmia eye] at all treatment levels only at 24 hours) At most highly toxic 

Form.: Dithane/ RH-117,281 75 DG Blend Mancozeb (69) Zoxamide (8.26) 

Rainbow trout (Oncorhynchus mykiss) 

LC50 (95% C.I.) = 162 (133-198) μg zoxamide /L (mm) 

Probit slope (95% C.I.) = 5.3 (3.3-7.4) NOAEC = 80 μg zoxamide /L (mm) LOAEC = 163 μg zoxamide /L (mm) LC50 (95% C.I.) = 1360 (1130-1600) μg mancozeb/L (mm) Probit slope (95% C.I.) = 6.2 (3.7-8.7) NOAEC = 680 μg mancozeb/L (mm) LOAEC = 1410 μg mancozeb/L (mm) LC50 (95% C.I.) = 1900 (1600-2300) μg form./L (mm) Probit slope = 6.0 NOAEC = 980 μg form./L (mm) LOAEC = 2000 μg form./L (mm) (NOAEC based on mortality and signs of toxicity including laborespiration, quiescence, surfacing, exophthalmia, and lying on thbottom at ≥ 2000 μg form./L) 

Freshwater fish early life stage: 61 days, flow-through (chronic) 

RH-117,281 Technical (92.9) 

14C-RH-117281 

(98.7) 

Rainbow trout (Oncorhynchus mykiss) 

NOAEC = 3.48 μg a.i./L LOAEC = 6.87 μg a.i./L (based on reduction in fry survival at 35 and 61 days post-hatch) 

 Freshwater fish life cycle: 219 days, flow-through 

RH-117,281 Technical (92.3) 

14C-RH-117,281 

(98.50) 

Fathead minnow (Pimephales promelas) 

NOAEC = 60 μg a.i./L (mm) LOAEC = 121 μg a.i./L (mm) (based on F0: reductions in day 32 and day 60 total length and F1

reductions in hatching success and 28-day survival and growth [land weight]) 
45 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

Estuarine/marine fish acute: 96 hours, flow-through 

RH-117,281 Technical (92.3) 

Sheepshead Minnow (Cyprinodon variegatus) 

LC50 > 860 μg a.i./L (mm) 

NOAEC = 860 μg a.i./L (mm) (no mortality or sublethal effects up to solubility, i.e., 860 μg/L) 

Practically non-toxic up to the limit of solubility 

Estuarine/marine fish early life stage: 28 days, flowthrough (chronic) 

RH-117,281 Technical (92.3) 

Sheepshead Minnow (Cyprinodon variegatus)

NOAEC = 40 μg a.i./L (mm) LOAEC = 78 μg a.i./L (mm) (based on a reduction in wet weight) 

Freshwater invertebrate acute: 48 hours, flowthrough 

RH-117,281 Technical (94.2) 

Water flea (Daphnia magna)

EC50 > 780 μg a.i./L (mm) 

NOAEC = 780 μg a.i./L (mm) (no immobility or sublethal effects; precipitate at highest concentration, considered to be the solubility limit under the conof this test) No more than highly toxic 

Form.: Dithane/RH117,281 75 DG BlendMancozeb (69) Zoxamide (8.26) 

Water flea (Daphnia magna)

EC50 (95% C.I.) = 306 (228-400) μg zoxamide /L (mm) 

Probit slope (95% C.I.) = 3.6 (2.0-5.3) NOAEC = 78.3 μg zoxamide /L (mm) LOAEC = 122 μg zoxamide /L (mm) EC50 (95% C.I.) = 2690 (2020-3580) μg mancozeb/L (mm) Probit slope (95% C.I.) = 3.5 (1.9-5.0) NOAEC = 558 μg mancozeb /L (mm) LOAEC = 1190 μg mancozeb /L (mm) EC50 (95% C.I.) = 3800 (3000-5000) μg form./L (mm) Probit slope (95% C.I.) = 3.8 (3.0-5.0) NOAEC = 820 μg form./L (mm) LOAEC = 1700 μg form./L (mm) (NOAEC base on mortality and the sublethal effect of lying on thbottom of the test chamber at ≥ 1700 μg form./L) 

Form.: Dithane/RH7281 80WP Mancozeb 

Water flea (Daphnia magna)

Preliminary endpoints 

EC50 = 471 μg form./L (mm) 

NOAEC = 312 μg form./L (mm) LOAEC = 601 μg form./L (mm) 
46 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

(67.8) Zoxamide  (7.21) 

Freshwater invertebrate life cycle: 21 days, flow-through (chronic) 

RH-117,281 Technical (92.3) 

Water flea(Daphnia magna) 

21-day NOAEC = 39 μg a.i./L (mm) 21-day LOAEC = 74 μg a.i./L (mm) (NOAEC based significant reduction in parental survival at ≥ 74 

Benthic invertebrate chronic: 28 days, over-lying water static exposure with sediment (chronic) 

RH-117,281 Technical (92.3) 

14C-RH-117,281 

(97.81) 

Midge (Chironomus riparius) 

Overlying water exposure NOAEC < 210 μg a.i./L (mm) LOAEC = 210 μg a.i./L (mm) (based on reduced development; for emergence, NOAEC = 210 μa.i./L; LOAEC = 340 μg a.i./L) 

Estuarine/marine invertebrate acute: 96 hours, flowthrough 

RH-117,281 Technical (92.3) 

Mysid shrimp(Mysidopsis bahia) 

LC50 (95% C.I.) = 76 (67-87) μg a.i./L (mm) 

Probit slope (95% C.I.) = 9.0 (5.2-12.9) NOAEC = 17 μg a.i./L (mm) LOAEC = 31 μg a.i./L (mm)  (NOAEC based on sublethal effect of erratic swimming at ≥ 31 lethargy at 132 μg/L – the highest treatment concentration) Very highly toxic 

RH-117,281 Technical (92.3) 

Eastern oyster (Crassostrea virginica) 

EC50 (95% C.I.) = 715 (535-957) μg a.i./L (mm) 

NOAEC = 123 μg a.i./L (mm) LOAEC = 238 μg a.i./L (mm) Highly Toxic 

Estuarine/marine invertebrate life cycle: 27 days, flow-through (chronic) 

RH-117,281 Technical (92.3) 

14C-RH-7281 

(96.3) 

Mysid shrimp(Mysidopsis bahia)

NOAEC = 7.2 μg a.i./L (mm) LOAEC = 14 μg a.i./L (mm) (NOAEC based on a reduction in reproduction and growth [lengtweight]) 

Aquatic vascular plant: 14 days, static-renewal 

RH-117,281 Technical (92.3) 

Duckweed (Lemna gibba) 

EC50 (95% C.I.) = 19 (16-27) μg a.i./L (mm) 

NOAEC = 9.0 μg a.i./L (mm) LOAEC = 18 μg a.i./L (mm) 
47 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

14C-RH-7281 

Technical (96.3) 

(NOAEC based on reduction in frond number; smaller-than-normroot size at three highest concentrations) 

Aquatic nonvascular plant: 96 hours, static 

RH-117,281 Technical (92.3) 

14C-RH-117,281 

(96.3) 

Green alga (Scenedesmus subspicatus) 

EC50 (95% C.I.) = 10 (7.8-13) μg a.i./L (mm) 

NOAEC = 7.0 μg a.i./L (mm) LOAEC = 14 μg a.i./L (mm) (NOAEC based on reduction in cell density; clumping/flocculaticellular enlargement at ≥14 μg a.i./L) 

Form.: Dithane/RH117,281 DG Blend  Mancozeb (69) Zoxamide  (8.26) 

Green alga (Selenastrum capricornutum) 

EC50 (95% C.I.) = 1.95 (1.52-2.51) μg zoxamide /L (TWA) 

NOAEC = 0.584 μg zoxamide /L (TWA) LOAEC = 1.16 μg zoxamide /L (TWA) EC50 (95% C.I.) = 9.42 (7.38-12) μg mancozeb/L (TWA) NOAEC = 2.68 μg mancozeb /L (TWA) LOAEC = 5.17 μg mancozeb /L (TWA) EC50 (95% C.I.) = 11.4 (8.91-14.2) μg form./L (TWA) NOAEC = 3.26 μg form./L (TWA) LOAEC = 6.33 μg form./L (TWA) (based on reduction in cell density) 

Form.: Dithane/ RH7281 (11.2:1) DG Blend Mancozeb (70.9) Zoxamide (6.25) 

Green alga (Selenastrum capricornutum) 

Preliminary endpoints 

EC50 (95% C.I.) = 6.6 (5.5-7.9) μg zoxamide /L (im)+

EC05 (95% C.I.) = 1.7 (1.1-2.6) μg zoxamide /L (im)+NOAEC = <0.489 μg zoxamide /L (im)+

EC50 (95% C.I.) = 61 (52-73) μg mancozeb/L (im)+

EC05 (95% C.I.) = 16 (11-24) μg mancozeb /L (im)+NOAEC = <4.36 μg mancozeb/L (im)+

EC50 (95% C.I.) = 71 (61-80) μg form./L (im)+

EC05 (95% C.I.) = 23 (15-34) μg form./L (im)+NOAEC = <6.3 μg form./L (im)+

(based on most sensitive endpoint of biomass) 

RH-117,281 Technical 

Cyanobacterium (Anabaena flos-aqua) 

EC50 > 860 μg a.i./L (im) 

NOAEC = 860 μg a.i./L (im) 
48 

Study Type Test Substance 

 (% a.i.) 

Species Toxicity Endpoints and 

Acute Toxicity Classification (If Applicable)

(92.3) (increase in cell density at ≥ 100 μg a.i./L) 

Marine diatom (Skeletonema costatum) 

EC50 > 910 μg a.i./L (im) 

NOAEC = 490 μg a.i./L (im) LOAEC = 910 μg a.i./L (im) (NOAEC based on reduction in cell density; 14, 7.3, 3.7, 7.7, and inhibition at 50, 110, 240, 490, and 910 μg/L in comparison to thnegative control) 

Freshwater diatom (Navicula pelliculosa) 

EC50 > 930 μg a.i./L (im) 

NOAEC = 210 μg a.i./L (im) LOAEC = 410 μg a.i./L (im) (NOAEC based on reduction in cell density; 2.4, 46, 1.5, 36 and inhibition at 60, 110, 210, 410, and 930 μg/L in comparison to negative control) 

Aquatic nonvascular plant: 120 hours, static 

RH-117,281 Technical (92.9) 

Green alga (Selenastrum capricornutum) 

EC50 (95% C.I.) = 23 (18-30) μg a.i./L (mm) 

NOAEC = 4.1 μg a.i./L (mm) LOAEC = 8.6 μg a.i./L (mm) (NOAEC based on reduction in cell density) 

C.I. = confidence interval; form. = formulation; im = initial measured; mm = mean measured; nom = nominal; NS = not specified; TEP product; TWA = time-weighted average + The four lowest treatment levels of RH-7281 were not analytically verified. The concentration at each of these levels of RH-117,281 

multiplying the percent of nominal recovery of RH-117,281 in the fifth lowest treatment level by the nominal concentration of RH-117

# endpoint calculated by multiplying the concentration in μg form./bee (as reported) by the % a.i. 
49 

Appendix D: Results of SIP and STIR 

SIP (v1.0) 

Table 1. Inputs 

Parameter Value 

Chemical name zoxamide 

Solubility (in water at 25oC; mg/L) 0.681 

 

Mammalian LD50 (mg/kg-bw) 5000 

Mammalian test species laboratory rat 

Body weight (g) of "other" mammalian species 

 

Mammalian NOAEL (mg/kg-bw) 409.3 

Mammalian test species laboratory rat 

Body weight (g) of "other" mammalian species 

 

Avian LD50 (mg/kg-bw) 2000 

Avian test species mallard duck 

Body weight (g) of "other" avian species 

Mineau scaling factor 1.15 

 

Mallard NOAEC (mg/kg-diet) 1000 

Bobwhite quail NOAEC (mg/kg-diet) 1000 

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

Body weight (g) of other avian species 

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

species 

Body weight (g) of 2nd other avian species 

Table 2. Mammalian Results 

Parameter Acute Chronic 

Upper bound exposure (mg/kg-bw) 0.1171 0.1171 

Adjusted toxicity value (mg/kg-bw) 3845.8028 314.8174 

Ratio of exposure to toxicity 0.0000 0.0004 

Conclusion* 

Drinking water exposure 

alone is NOT a potential 

concern for mammals 

Drinking water exposure 

alone is NOT a potential 

concern for mammals 

Table 3. Avian Results 

Parameter Acute Chronic 

Upper bound exposure (mg/kg-bw) 0.5516 0.5516 

Adjusted toxicity value (mg/kg-bw) 1038.4508 49.6126 

Ratio of exposure to acute toxicity 0.0005 0.0111 

Conclusion* 

Drinking water exposure 

alone is NOT a potential 

concern for birds 

Drinking water exposure 

alone is NOT a potential 

concern for birds 

 

*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. 
50 

STIR (v1.0) 

Welcome to the EFED Screening Tool for Inhalation Risk 

This tool is designed to provide the risk assessor with a rapid method for determining 

the potential significance of the inhalation exposure route to birds and mammals in a 

risk assessment. 

Input 

Application and Chemical Information 

Enter Chemical Name zoxamide 

Enter Chemical Use grapes 

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

If Spray What Type (enter ground or air) air 

Enter Chemical Molecular Weight (g/mole) 336.1 

Enter Chemical Vapor Pressure (mmHg) 1.00E-07 

Enter Application Rate (lb a.i./acre) 0.21 

Toxicity Properties 

Bird 

Enter Lowest Bird Oral LD50 (mg/kg bw) 2000 

Enter Mineau Scaling Factor 1.15 

Enter Tested Bird Weight (kg) 0.178 

Mammal 

Enter Lowest Rat Oral LD50 (mg/kg bw) 5000 

Enter Lowest Rat Inhalation LC50 (mg/L) 5.3 

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) 1.81E-03 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.27E-04 

Adjusted Inhalation LD50 1.18E+01 

Ratio of Vapor Dose to Adjusted Inhalation LD50 1.92E-05

Exposure not Likely 

Significant 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 2.02E-02 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD50 1.71E-03

Exposure not Likely 

Significant 

Results Mammalian (0.015 kg ) 

Maximum Vapor Concentration in Air at Saturation (mg/m3) 1.81E-03 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.86E-04 

Adjusted Inhalation LD50 3.16E+02 

Ratio of Vapor Dose to Adjusted Inhalation LD50 9.06E-07

Exposure not Likely 

Significant 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 2.54E-02 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD50 8.04E-05

Exposure not Likely 

Significant