1 OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON

, D.C. 20460

November 3, 2014

PC Code: 055501 MEMORANDUM DP Barcode: D422219

SUBJECT: Registration Review: Preliminary Problem Formulation for Environmental Fate, Ecological Risk, Endangered Species, and Human Health Drinking Water Exposure Assessments for Ethoxyquin

FROM: James N. Carleton, Ph.D. Environmental Risk Branch IV Environmental Fate and Effects Division (7507P)

REVIEWED BY: Elyssa Arnold, MEM, MPH, Acting Risk Assessment Process Leader Thomas Steeger, Ph.D., Senior Science Advisor Environmental Risk Branch IV Environmental Fate and Effects Division (7507P)

THROUGH: Thomas Steeger, Ph.D., Acting Branch Chief Environmental Risk Branch IV Environmental Fate a nd Effects Division (7507P)

TO: Khue Nguyen, Chemical Review Manager Tom Moriarty, Team Leader Neil Anderson, Branch Chief Risk Management and Implementation Branch I Pesticide Re-evalua tion Division (7508P)

The Environmental Fate and Effects Division (E FED) has completed the preliminary problem formulation for the ecological risk, environmenta l fate, endangered species, and drinking water assessments to be conducted as part of the Registration Review of e thoxyquin . The problem formulation describes the methods planned to be used during the completion of drinking water and ecological risk assessments in support of Re gistration Review and provides an overview of the environmental fate, ecological effects, and potential risks associat ed with the use of ethoxyquin as well as uncertainties unique to the risk assessme nt of ethoxyquin. Uncertainties include:2 Data Needs

 The fate database is incomplete based on the environmental fate data requirements outlined in the Code of Federal Regulations Title 40 Part 158 ( 40CFR158) Subpart N 1 and data are needed to reduce uncertainty in the risk assessment. Additional data on the following fate parameters are recommended.

o Hydrolysis data (OCSPP Guideline 835.2120) . The previously submitted study (MRID 437531-01) did not defini tively identify four majo r degradates (analytical methodology was not adequate to provide defi nitive structural identification) and therefore does not fulfill the guide line requirement for a hydrolysis study.

o Adsorption/desorption data (OCSPP Guideline 835.1230).

o Aqueous photolysis data (OCSPP Guideline 835.2240).

o Aerobic aquatic metabolism da ta (OCSPP Guideline 835.4300).

 The ecotoxicity database is incomplete for the purposes of assessing risk to aquatic organisms. Additional data on th e following taxa are recommended:

o Daphnid chronic toxicity test (OCSPP 850.1300)

o Freshwater fish early-life st age toxicity test (OCSPP 850.1400)

o Vascular aquatic plant toxicity test (OCSPP 850.4400)

o Non-vascular aquatic plant toxicity test (OCSPP 850.4500)

Other Major Uncertainties

 Although ethoxyquin is only applied within indoor pear storage and packing facilities, it is EPA’s understanding that such facilities may be hosed dow n for cleaning purposes and that packing facilities using the drench or spray applications may generate waste water containing ethoxyquin during this process. Howeve r, disposal practices for the resulting drainage that may contain ethoxyquin resi dues are not well defined. Information concerning disposal of the waste water ha s been requested from the registrants and industry trade organizations, but has not been received

. Although the limited nature of the application of ethoxyquin may preclude the possi bility of ecologica l exposure, until the requested information has been received and evaluated, such exposures to aquatic organisms cannot be ruled out.

 When facilities in which thermal fogging is employed for ethoxyquin are ventilated, exposure of non-target organisms to ethoxyqui n residues in vapor and/or in aqueous solution (following deposition or partitioning to surface waters), may occur. Based upon conservative screening-level calculations employing the limited available chemical property and toxicity data, consequent ri sks to mammals are considered unlikely; however, risks to aquatic ta xa cannot be ruled out.

1 CFR. 2013. Title 40 (Protection of the Environment), Chapter 1 (Environmental Protection Agency), Subchapter E (Pesticide Programs), Part 158 (Data Requirements for Pe sticides), Subpart N (Environmental Fate) http://www.ecfr.gov/cgi-bin/textidx?c=ecfr&SID=ff5c7fef3645e7cd5abceca0b597bccb &tpl=/ecfrbrowse/Title40/40cfr158_main_02.tpl3 

### Table of Contents
1. Executive summary ............................................................................................................. .... 3 2. Introduction .................................................................................................................. ........... 4 3. Use Characterization .......................................................................................................... ..... 4 4. Conclusions from Previous Risk Assessments ....................................................................... 5

a. Previous Assessments .......................................................................................................... .5 b. Clean Water Act Programs ...................................................................................................5 5. Environmental Fate and Transport.......................................................................................... 5 6. Receptors...................................................................................................................... ........... 6

a. Effects to Aquatic and Terrestrial Organisms .......................................................................6 b. Ecological Incidents .......................................................................................................... ....7 7. Exposure Pathways of Concern .............................................................................................. 8 8. Analysis Plan ................................................................................................................. ......... 9

a. Ecological Risk Assessment .................................................................................................9 b. Drinking Water ................................................................................................................ ...10

c. Monitoring Data ............................................................................................................... ...10 9. Endangered Species Assessments ......................................................................................... 10 10. Endocrine Disruptor Screening Program ........................................................................... 10 11. Preliminary Identification of Data Gaps ............................................................................ 11

a. Environmental Fate ............................................................................................................ .11 b. Effects ....................................................................................................................... ..........12 12. References .................................................................................................................... ...... 13



## 1. Executive summary

The problem formulation for the Registration Re view of the fungicide ethoxyquin describes the methods planned to be used during the comp letion of drinking water and ecological risk assessments. This document also provides a preliminary overview of the environmental fate, ecological effects, and potenti al risks and uncertainties associated with the use of e thoxyquin

. Ethoxyquin is an antioxidant registered for pos t-harvest use on pears to control scald 2

. Application methods include impregnated paper wr aps, thermal fogging, and spray or drench.

Available environmental fate and ecotoxicity data are lim ited. Ethoxyquin is a soluble and volatile compound with a hydrolysis half-life of approximately 7 days at pH 7. Toxicity studies demonstrate slight to moderate acute toxicity to aquatic animal s and practically no toxicity to terrestrial animals on an acute exposure basis. No prior quantitative ecological risk assessments have been performed by the Agency for et hoxyquin due to uncertainti es regarding outdoor exposure pathways.

2 Scald is characterized as a physiological disease that produced brown to black discoloration of the skin of multiple varieties of pears and has been associated with fruit that have turned color in storage and lost their capacity to ripen normally. Although the discoloration is initially superficial, it can progress to where fruit skin sloughs of f readily and is followed by decay (Washi ngton State University Tree Fruit Research and Extension Service http://postharvest.tfrec.wsu.edu/marketdiseases/pearcommonscald.html ).4 

## 2. Introduction

EFED reviewed available toxicity, exposure, and us age information to determine if sufficient data are available to support the Registration Re view of ethoxyquin. The only available risk assessment is a 2008 assessment of the use of e thoxyquin applied via thermal fogging on postharvest pears (D341198, 341199, 341201). In addition, EFED considered the latest Agency science policies and risk assessment methodologies in determining whether additional data should be recommended. The structure of e thoxyquin , as well as the chemical name and other identifiers can be found in Section 5.



## 3. Use Characterization

The fungicide ethoxyquin (6-ethoxy -1,2-dihydro-2,2,4-trimethylquinoline ) is a quinolone-based antioxidant used to control scald (browning) in post-harvest pears. Regi stered end-use products include impregnated materials, i.e ., PEAR WRAP ® III (Reg. no. 61718-1), PEAR WRAP ® I (Reg no. 61718-4), ETHOXYWRAP ® (Reg. No. 84127-2), BURROWS ® E WRAP (Reg. no. 85199-4 and BURROWS CE WRAP ® (Reg. no. 85199-11), a soluble concentrate (XEDAQUIN ® ; Reg. no. 64864-60), and an emulsifiable concentrate (XEDAQUIN ® DRENCH; Reg. no. 64864-58). Another emulsifiable con centrate (ECOFOG-180; Reg no. 64864-64) is registered for manufacturing use only. All applications are made to pears in storage and prior to packing. Application methods include thermal electr ofogging, drench and line spraying, and use of ethoxyquin-impregnated paper. The us es are summarized below in Table 1

. Table 1. Ethoxyquin Use Table 1

EPA Registration

Numbers Application Type/ Equipment Single Application Rate Max # Applications Max Dose/ Crop Cycle Application Specific Restrictions

64864-60 Xeda Brand Thermal Electrofogger 60 g per metric ton of fruit (1.9 oz per ton) NS NS (none)

64864-58 Drench

2700 ppm 1 2700 ppm  Do not use in combination with line spray.

 Can be applied as a single or split

application as long as the maximum dose of 2700 ppm is not exceeded.
Line Spray (on

brush bed or conveyor rolls)  Do not use in combination with drench.

 Can be applied as a single or split

application as long as the max dose of 2700 ppm is not exceeded.

61718-1 61718-4 84127-2 85199-4 85199-11 Impregnated
paper 1000 ppm NS see restrictions  Wrap fruit within 1 week post-harvest.

 Wraps contain a ma ximum of 1,000 ppm

ethoxyquin. They can be used on pears that have received prior treatment with ethoxyquin providing those pears were sprayed only once with no more than 1700 ppm of ethoxyquin, or drenched only once with no more than 1,000 ppm of ethoxyquin.

 Do not re-use fruit wraps.

1 Table prepared by the Biological and Econom ic Analysis Division (BEAD) on May 16, 2014.5 

## 4. Conclusions from Previous Risk Assessments

a. Previous Assessments A 2008 assessment (USEPA, D341198, D341199, D 341201) of the then-pending Section 3 registration of the sol uble concentrate (ECOFOG ® -180; Reg. no. 64864-60) intended for use in thermal fogging, noted that the label directions specify that app lications take place within a treatment room “enclosed with” plastic sheeting and sealed with duct tape. Because this method of application is limited to indoor locations, the previous review concluded that the potential for environmental exposures was limited, and that potent ial risks to terrestrial and aquatic non-target organisms, including Federally listed threatened or endangered (hereafter referred to as “listed”) species, were therefore not antici pated. Drinking water exposures were not specifically addressed.



### b. Clean Water Act Programs Ethoxyquin is not identified as a cause of impa irment for any water bodies listed as impaired under section 303(d) of the Clean Water Act. 3 No Total Maximum Daily Loads (TMDL) or section 304(a) ambient water quality crit eria have been developed for ethoxyquin. 4 Aquatic life benchmarks 5 have not been established for ethoxyquin; however, any data submitted or otherwise located as part of the Registration Review process may be used to develop aquatic life benchmarks if applicable.



## 5. Environmental Fate and Transport

No acceptable environmental fate data are cu rrently available for ethoxyquin. A hydrolysis study (MRID 437531-01), conducted in 1995, was determined by EFED to be “scientifically valid,” but the study did not meet Subdivision N guide lines, because four major degradates ( i.e ., each > 10% of applied radioactivity) were isolated, but were only tentativel y identified, with more than one possible structure proposed for each, based upon mass spectral information. Parent ethoxyquin decayed with calculated half-lives of 3.7, 6.7, and 9.3 days in aqueous solutions buffered at pH 5, 7, and 9, respectively. The available chemical prope rties and environmental fate parameters are summarized in Table 3 . Due to limited data, there is uncertain ty regarding the extent to which the compound may be subject to abiotic routes of degrad ation such as photolysis, or biotic routes of degradation in aerobic or anaerobic environments.

No monitoring data are available for ethoxyquin. Th ere is uncertainty whether this reflects the low levels in the environment or whether current monitoring programs may not include ethoxyquin as an analyte.

3 Specific state causes of impairment that make up the na tional pesticides cause of impairment group are listed at http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885

4 Specific state pollutants that make up the National Pe sticides Pollutant Group and have TMDLs are listed at http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_p ollutant_detail?p_pollutant_group_id=885&p_pollutant_gr oup_name=PESTICIDES

5 Aquatic Life Benchmarks are available at http://www.epa.gov/oppefed1/ecorisk_d ers/aquatic_life_benchmark.htm6 Table 2. Ethoxyquin Chemical Identity Table Code Name/ Synonym Chemical Name Chemical Structure Ethoxyquin 6-ethoxy-1,2-dihydro-2,2,4- trimethylquinoline

CAS No.: 91-53-2

Formula: C 14 H 19 NO

MW: 217.31 g/mol

Table 3. Ethoxyquin Chemical Propertie s and Environmental Fate Parameters
Parameter Value Source Selected Physical/Chemical Parameters Vapor pressure (25 °C) 2.6 x 10 -4 torr MRID 439474-01

Aqueous solubility (25  C) 170 ppm MRID 439723-01

Henry’s Law Constant (25°C) 4.37 x 10 -7 atm·m 3 ·mol -1 Calculated Log octanol-to-water partition coefficient (log K O W ) (25°C) 2.45 MRID 439632-01

Dissociation constant (pKa) 8.65 MRID 491489-05
Persistence in Water

Hydrolysis half-life (25  C) pH 5: 3.7 d pH 7: 6.7 d pH 9: 9.3 d MRID 437531-01



## 6. Receptors
a. Effects to Aquatic and Terrestrial Organisms Two aquatic toxicity studie s are available for ethoxyquin, i.e ., acute toxicity studies on freshwater fish and on freshwater invertebra tes. These studies show that et hoxyquin is slightly toxic to the rainbow trout ( Oncorhynchus mykiss ; LC 50 = 18 mg a.i./L) and m oderately toxic to the invertebrate waterflea ( Daphnia magna ; EC 50 = 2 mg a.i./L) on an acute exposure basis. Both studies were conducted using flow-through syst ems with methanol as a solvent. See Table 4 for details.

One avian toxicity study is available for et hoxyquin, which demonstrates that ethoxyquin is practically non-toxic to bobwhite quail ( Colinus virginianus ) on a sub-acute dietary exposure basis (LC 50 >5850 mg a.i./kg-bw, no mort ality observed in the study) . Studies on the laboratory rat ( Rattus norvegicus ) show that ethoxyquin is practically no n-toxic to mammals on an acute oral basis (LD 50 = 1726 mg a.i./kg-bw). In an acute inhala tion study conducted on the laboratory rat at 1.97 mg a.i./L, no LC 50 was established but clinical signs of toxicity included tremors, unkempt7 appearance and reductions in body weight. No 2-generation re production study is available, but a developmental study on the laboratory rat demons trated maternal toxic ity at 150 mg a.i./kgbw/day (NOAEL = 50 mg a.i./kg-bw/day); howev er, offspring did not demonstrate adverse effects up to the highest level test ed (350 mg a.i./kg-bw/day). See Table 4 for details.

No other data on the effects of ethoxyquin on non-ta rget biological receptors have been submitted to the Agency.

Table 4. Summary of the Most Sensitive Endp oints from Toxicity Studies for Ethoxyquin

Taxonomic

Group Study Type Species Toxicity Value (measured a.i.) Acute Toxicity Classification MRID (Study Classification) Aquatic Toxicity Endpoints
Freshwater Fish& Aquaticphase Amphibians Acute Rainbow trout ( Oncorhynchus mykiss ) 96 hr LC 50 = 18 mg/L Slightly toxic 43978301 (Acceptable)

Freshwater Invertebrates Acute Daphnia magna 48 hr LC 50 = 2 mg/L Moderately toxic 43978401 (Acceptable) Terrestrial Toxicity Endpoints Birds, Reptiles,& Terrestrialphase Amphibians Sub-acute dietary Bobwhite quail ( Colinus virginianus ) LC 50 > 5850 mg/kgbw Practically nontoxic 43978101 (Acceptable)

Mammals Acute oral Laboratory rat ( Rattus norvegicus ) LD 50 = 1726 mg/kg-bw (M&F) Practically nontoxic 43885901 (Acceptable)

Acute inhalation Laboratory rat 4 hr LC 50 > 1.97 mg/L Toxicity category III 43894101 (Acceptable)

Developmental Laboratory rat NOAEL = 50 LOAEL = 150 mg/kg-bw/day Not applicable 44098901 (Acceptable)



### b. Ecological Incidents The ecological incident information system (EIIS ) is a database maintained by the Office of Pesticide Programs (OPP) containing ecological incidents that have been reported to the Agency. When available, EIIS includes da te and location of an incident, type and magnitude of effects observed in various species, use(s) of pesticid es known or suspected of contribu ting to the incident, and results of any chemical residue analysis or other anal yses conducted during the incident investigation. The Avian Monitoring Syst em (AIMS) is a database administered by the American Bird Conservancy that contains publi cly available data on reported avian incidents involving pesticides.

As of August 28, 2014, there were no ecological incidents reported in EIIS or AIMS for ethoxyquin. There were also no incidents reported in a ggregate incident reports.8 

## 7. Exposure Pathways of Concern

Previous assessments have concl uded that the use patterns of e thoxyquin imply the lack of any meaningful transport mechanisms of the chemical to aquatic or terrestrial habitats, and therefore the absence of any potential expos ure pathway for aquatic or terrestrial organisms. However, given EPA’s current understanding that pear treatment facilities may generate waste water, which despite the chemical’s volatility could contain ethoxyquin residues, there is uncertainty regarding common handling practices of the resulting waste wate r. Therefore, there is uncertainty regarding whether this water might be releas ed to the outdoor environment ( e.g ., to a holding pond), where ethoxyquin exposures to non-target organisms could occur. Wa ste water containing ethoxyquin residues may result from (1) washing out of treatment facilities in which thermal fogging applications of ethoxyquin occurred or (2) waste wa ter generated from packing facilities in which drench or spray applications of ethoxyquin are use d. In order to better und erstand this potential pathway, EPA has requested information about wast e water treatment in pear storage and packing facilities from the ethoxyquin registrant s and industry trade organizations.

EFED notes that the following langua ge is included on the labels for the spray/drench and thermal fogger products, EPA Reg. No. 64864-58 and 64864-60: “ Do not discharge effluent containing this product into lakes, streams, ponds, estuaries, oceans, or ot her waters unless in accordance with the requirements of a National Pollutant Discharge Elimination System (NPDES) permit and the permitting authority has been no tified in writing prior to disc harge. Do not discharge effluent containing this product to sewer systems without previously notifyi ng the local sewage treatment plant authority. For guidance, c ontact your State Water Board or Regional Office of the EPA. ”

Because ethoxyquin is volatile, when facilities in which thermal fogging is employed to apply the chemical are ventilated, exposure of non-target organisms to residues in vapor form and/or in aqueous solution (following deposition or partit ioning to surface waters), may occur. Because EPA currently lacks information on ventilation pract ices for pear handling and storage facilities, conservative screening-level calc ulations were conducted to repr esent these exposure pathways. Non-target organisms that might be exposed include terrestrial wildlife ( i.e ., birds [which serve as surrogates for terrestrial-phase amphibians and re ptiles] and mammals), aquatic invertebrates and fish (which serve as surrogates for aquatic-phase amphibians), and terrestrial and aquatic plants. For the screening-level calculations, it was assumed that c oncentrations of ethoxyquin would be at their maximum possible values, i.e ., saturation in air, and in wate r. The saturation concentration in water is given in Table 3 . The saturation air concentration at 25oC was calculated as follows:

ܥ

௥௜௔ ൌ ܸܲ ൈ ܯܹ ൈ 1000
760 ൈ ܸ ௠ ܮ݉݃/	0.003 ൌ

where: C air = air vapor concentration (mg/L) of the pesticide at saturation VP = vapor pressure (2.6 x10 -4 torr) V m = volume in liters (24.45) occupi ed by 1 mol of gas at 25oC and 1atm, as calculated using the ideal gas law (PV = nRT) MW = molecular weight (217.31 g/mol) 760 = conversion from torr to atm 1000 = conversion from m 3 to L9 Based upon the saturation air con centration and results of the acute inha lation rat study ( Table 4 ), a back-of-the-envelope, worst-case risk quotient (RQ; the ratio of exposure to toxicity) of <0.0015 is calculated; therefore the lik elihood of adverse effects on non-target mammals from acute inhalation exposure to ethoxyquin is considered low. Inhalation toxicity data are not available for birds; however, the likelihood of adverse effect s on birds, reptiles and terrestrial-phase amphibians from acute inhalation exposure is co nsidered low based on the available mammalian inhalation and avian sub-acute dietary toxicity data and that the highest inhalation exposure levels are likely confined to indoor areas.

Based upon the water saturation concentration of 170 mg/L ( Table 3 ) for ethoxyquin, worst-case RQs of 9.5 and 85.1 are estimated for freshwater fish and aquatic invert ebrates, respectively ( Table 4 ); therefore risks to these ta xa, including aquatic-phase amphi bians cannot be ruled out at this time. Water containing ethoxyquin residues may also be used as drinking water by terrestrial animals. However, based on the low dietary toxi city of ethoxyquin to birds and mammals this exposure pathway is not expected to result in risks of concern.

Drinking water and inhalation e xposure pathways are typically considered using the SIP (Screening Imbibition Program) and STIR (Scr eening Tool for Inhalation Risk) screening methods. However, due to the lack of acute oral a nd chronic toxicity data for birds, quantitative use of these tools is not possibl e for ethoxyquin at this time. SIP a nd STIR are described in detail
at: http://www.epa.gov/oppefed1/mo dels/terrestrial/index.htm

.


## 8. Analysis Plan

a. Ecological Risk Assessment

Given the slight toxicity of ethoxyqui n to freshwater fish, and the ch emical’s moderate toxicity to freshwater aquatic invertebrate s, ethoxyquin could pose risks to aquatic organisms if it were released or discharged into surface waters. No data are available on the chronic toxicity of ethoxyquin to aquatic organisms. Given the chemical’s limited use patterns, there do not appear to be major transport pathways through which non-ta rget receptors are likely to be exposed to substantial residues of ethoxyquin. However, uncerta inty exists concerning the routine handling of pear treatment facility wash water and waste wa ter, and concerning procedures involved in the ventilation of thermal fogging facili ties. On the basis of conservative calculations and in the face of these uncertainties, risks to non-target organisms cannot be de finitively ruled out. OPP has sought to address these uncertainti es with questions asked of th e registrants and industry trade organizations. Pending receipt of additional inform ation, EFED plans to quantitatively evaluate potential risks to aquatic organisms exposed to waste water from the spray/drench uses in pear packing facilities. EFED may also further refi ne calculations employed to quantify exposures resulting from ventilation of thermal fogging facilities.

The use of ethoxyquin in impregnated paper is no t expected to result in any significant environmental exposure and therefor e will not be assessed by EFED.10 Since the use of ethoxyquin is limited to indoors, there is a low likel ihood of exposure to terrestrial animals foraging on gra ss, broadleaf plants, or insects. Therefore, pot ential risks to these organisms as well as terrestrial plants will not be assessed gi ven the low likelihood of exposure to ethoxyquin residues.



### b. Drinking Water

Given ethoxyquin’s limited use patterns, there are no known transport pathways by which humans might plausibly be exposed to ethoxyquin residues in drinking water. Nevertheless, questions exist concerning the handling of pear treatment facility wash water, which OPP has asked the registrants to address. Pending receipt of th is information, EFED will evaluate whether a quantitative assessment of drinking water exposures is appropriate.

If either ecological or drinking water exposure calculations are deemed necessary, EFED may employ standard models to evaluate potential hu man and/or ecological expos ures as described at http://www.epa.gov/pesticides/science/models_db.htm . In addition, the Exposure and Fate Assessment Tool (E-FAST) or other available mode ls may be used to assess exposures resulting from wash water disposal in drains , waste water systems, storm sewers, etc . E-FAST is described in detail at http://www.epa.gov/oppt/exposure/pubs/efast.htm

.



### c. Monitoring Data

As noted earlier, EPA is not aware of any m onitoring for ethoxyquin that has been conducted by federal or state agencies. Should such data become available, they will be considered in the
assessment.



## 9. Endangered Species Assessments

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency will evaluate risks to listed species from registered uses of pesticides in Registration Review. The process for evaluating potential risk s to listed species is further described at http://www.epa.gov/oppfead1/enda nger/litstatus/riskasses.htm

.


## 10. Endocrine Disruptor Screening Program

Ethoxyquin was not included in the first group of 67 ch emicals issued an order to conduct Tier 1 EDSP testing. Ethoxyquin is also not on the second list of chemicals for Tier 1 EDSP screening. For additional information the EDSP program, visit http://www.epa.gov/endo/

.11 

## 11. Preliminary Identification of Data Gaps

a. Environmental Fate
Table 5 identifies environmental fate studies by master record identification (MRID) number that offer data for each guideline requirement, as we ll as study classifications and whether or not further data are needed in or der to support risk assessment.

Table 5. Submitted Environmenta l Fate Data for Ethoxyquin

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are additional data needed

for risk assessment? Justification and Assumptions EPA will Make in Absence of Data

835.2120 Hydrolysis 437531-01 Supplemental Yes In the absence of data, stability will be assumed.

835.2240 Aqueous photolysis (None) (Not applicable) Yes Data will be used to assess potential aquatic exposure. In the absence of data, stability will be assumed.
835.2410 Soil photolysis (None) (Not applicable) No Terrestrial exposure will not be assessed.

835.4100 Aerobic soil metabolism (None) (Not applicable) No Terrestrial exposure will not be assessed.

835.4200 Anaerobic soil metabolism (None) (Not applicable) No Terrestrial exposure will not be assessed.

835.4300 Aerobic aquatic metabolism (None) (Not applicable) Yes Data will be used to assess potential aquatic exposure. In the absence of data, stability will be assumed.

835.4400 Anaerobic aquatic metabolism (None) (Not applicable) No Data are not expected to impact risk
assessment.

835.1230 835.1240 Adsorption/ desorption and leaching (None) (Not applicable) Yes Data will be used to assess potential aquatic exposure. In the absence of data, stability will be assumed.

835.1410 Volatility – laboratory (None) (Not applicable) No Data are not expected to impact risk
assessment.

835.6100 Terrestrial field dissipation (None) (Not applicable) No Terrestrial exposure will not be assessed given the indoor use of the product. 850.6100 Analytical method in soil (None) (Not applicable)

835.6200 Aquatic field dissipation (None) (Not applicable) No Data are not expected to impact risk
assessment. 850.6100 Analytical method in water (None) (Not applicable)
165-4 (850.1730) Fish bioconcentration (None) (Not applicable) No Data are not expected to impact risk
assessment.12 

### b. Effects

Table 6 and Table 7 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.

Table 6. Submitted Aquatic Ecological Effects Data for Ethoxyquin

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are additional data needed

for risk assessment? Justification and Assumptions EPA will Make in Absence of Data

850.1010 Freshwater invertebrate acute toxicity 439784-01 Acceptable No N/A

850.1025 850.1035 850.1045 850.1055 Saltwater invertebrate acute toxicity (None) (N/A) No Significant exposure in estuarine/marine environments is not expected.

850.1075 Freshwater fish acute toxicity 439783-01 Acceptable No N/A

850.1075 Saltwater fish acute toxicity (None) (N/A) No Significant exposure in estuarine/marine environments is not expected.

850.1300 Freshwater invertebrate

life cycle (None) (N/A) Yes There is potential for chronic exposure to aquatic organisms. In the absence of data, toxicity will be assumed.

850.1350 Saltwater invertebrates

life cycle (None) (N/A) No Significant exposure in estuarine/marine environments is not expected.

850.1400 Freshwater fish early-life stage (None) (N/A) Yes There is potential for chronic exposure to aquatic organisms. In the absence of data, toxicity will be assumed.

850.1400 Saltwater fish early-life stage (None) (N/A) No Significant exposure in estuarine/marine environments is not expected.

850.1500 Fish life cycl e (None) (N/A) No Data are not expected to impact risk assessment.

850.4400 Aquatic plant Toxicity Test using Lemna
spp. (None) (N/A) Yes There is potential for exposure to aquatic plants. In the absence of data, toxicity will be assumed.

850.4500 Algal toxicity (None) (N/A) Yes There is potential for exposure to aquatic plants. In the absence of data, toxicity will be assumed.

850.4550 Cyanobacteria (None) (N/A) No Data is not expected to impact risk
assessment.13 Table 7. Submitted Terrestrial Ecologi cal Effects Data for Ethoxyquin

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are additional data needed

for risk assessment? Justification and Assumptions EPA will Make in Absence of Data

850.2100 Avian oral toxicity (None) (N/A) No Terrestrial exposure will not be assessed.

850.2200 Avian dietary toxicity 439781-01 Acceptable No N/A

850.2300 Avian reproduction (None) (N/A) No Terrestrial exposure will not be assessed.

Nonguideline Avian inhalation (None) (N/A) No Terrestrial exposure will not be assessed.

850.3020 Honey bee
acute contact toxicity (None) (N/A) No Terrestrial exposure will not be assessed.

850.3030 Honey bee residue on

foliage (None) (N/A) No Terrestrial exposure will not be assessed.

850.3040 Field testing for pollinators (None) (N/A) No Terrestrial exposure will not be assessed.

850.4100 Seedling Emergence (None) (N/A) No Terrestrial exposure will not be assessed.

850.4150 Vegetative Vigor (None) (N/A) No Terrestrial exposure will not be assessed.



## 12. References

Mackay, D., Shiu, W. Y., Ma, K. C., & Lee, S. C. 1999. Physical–chemical properties and environmental fate and degradation handbook. CRCnet Base . Boca Raton, FL: Chapman & Hall/CRCnet Base. USEPA, 2008. Review of Section 3 New Appli cation Method, Thermal Fogging, for the use of Ethoxyquin (Xedaquin A) on Pears. Memora ndum from Marietta Echeverria, Environmental Fate and Effects Division, to John Bazuin and Tony Kish, Registration Division, Office of Pesticide Programs, U.S. Environmen tal Protection Agency. DP Barcodes 341198, 341199, 341201. Dated March 31, 2008.

Studies by MRID

MRID 43753101. Reynolds, J.; Campbell, M. (1995) H ydrolysis of (carbon 14)-Ethoxyquin: Lab Project Number: ABL 95011: RPT00229: X336. Unpublished study prepared by XenoBiotic Labs, Inc. 160 p.14 MRID 43885901. Varsho, B. (1995) Acute Oral Toxi city Study of Ethoxyquin in Albino Rats: Final Report: Lab Project Number: WIL-273001. Unpublished study prepared by WIL Research Labs, Inc. 86 p. MRID 43894101. Ulrich, C. (1996) Acute Inhalation Toxicity Study of Ethoxyquin in Rats: Final Report: Lab Project Number: WIL-273006. Unpublis hed study prepared by WIL Research Labs, Inc. 81 p. MRID 43947401. Schetter, J.; Kogovsek, L. (1996) Ethoxyquin--Vapor Pr essure: Lab Project Number: 4368-95-0189-AS-001: 4368-95-0189-AS -000. Unpublished study prepared by Department of Analytical Services, Ricerca, Inc. 55 p. MRID 43963201. Lorence, P. (1996) Ethoxyquin--Oct anol/Water Partition Coefficient: Lab Project Number: 4368-95-0204-AS-001: 4368-95-0204-AS-000. Unpublished study prepared by Ricerca, Inc. 52 p. MRID 43972301. Lorence, P. (1996) Ethoxyquin--S olubility: Lab Project Number: 4368-95- 0177-AS-001: 4368-95-0177-AS-000: 4368-95-0177- AS. Unpublished study prepared by Dept. of Analytical Servi ces, Ricerca, Inc. 50 p.
MRID 43978101. Palmer, S.; Martin, K.; Beavers, J. (1996) Ethoxyquin T echnical: A Dietary LC50 Study with the Northern Bobwhite: Lab Project Number: 442-101. Unpublished study prepared by Wildlife Int'l. Ltd. 45 p. MRID 43978301. Drottar, K.; Swigert, J. ( 1996) Ethoxyquin: A 96-Hour Flow-Through Acute Toxicity Test with the Rainbow Trout (Onc orhychus mykiss): Final Report: Lab Project Number: 442A-101A: 442/122095/RBT-96H2/CH P107: 442A-101. Unpublished study prepared by Wildlife International Ltd. 65 p. MRID 43978401. Drottar, K.; Swigert, J. ( 1996) Ethoxyquin: A 48-Hour Flow-Through Acute Toxicity Test with the Cla doceran (Daphnia magna): Final Report: Lab Project Number: 442A-102: 442/122095/DAP-48H2/CHP107. Unpub lished study prepared by Wildlife Int'l. Ltd. 66 p. MRID 44098901. Nemec, M. (1996) A Developmental Toxicity Study of Ethoxyquin in Rats: Final Report: Lab Project Number: WIL-273009. Unpublished study prepared by WIL Research Labs., Inc. 360 p. MRID 49148905. Todhunter, J.; Tatanus, C. (2013) Product Chemistry, Series 63 (Physical & Chemical Properties) Ethoxyquin from Alternat e Sources for Formulation of E Wrap and CE Wrap. Project Number: BURROWS /E/CE/WRAP/ALT/EQ/SERIES/63/2013. Unpublished study prepared by SRS International Corporation. 11p.