Aventis response: Aventis is not supporting the cotton use and has removed this crop from the labels. Aventis CropScience requested cancellation of this use in a letter to Mr. George Tompkins, RD, on January 22, 1999. A Federal Register Notice dated April 14, 1999 announced receipt by the Agency of an application from RhonePoulenc Ag Company (now Aventis CropScience) to cancel the use of carbaryl products on cotton. 52 Page: 97 Paragraph: 3 Lines 1 4 EPA comment: The registrant does not intend to support carbaryl on avocados, barley, maple sap, oats, rye, and sweet sorghum; however, IR 4 has indicated (correspondence from K. Dorschner, IR 4 Project, 9/ 15/ 94) that they may fulfill the residue data requirements for some of these commodities. These data have not been submitted.

Aventis response: IR 4 has not generated the residue data necessary to support these uses. Aventis CropScience will not support these uses.

Page: 97 Paragraph: 4 Lines 1 2 EPA comment: The reregistration requirements for magnitude of the residue in livestock commodities are not fulfilled. Additional data are required to support dermal and poultry house uses.

Aventis response: Aventis CropScience will neither support dermal nor poultry house uses of carbaryl. A request for cancellation of these uses in accordance with section 6( f)( 1) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) will be submitted shortly to the Agency. 53 Line by Line Review of the Supporting Document "Product and Residue Chemistry Chapters for the Reregistration Eligibility Decision (Felecia Fort; November 14, 2000)"

Cover Memo Residue Chemistry Page 2 Paragraph 3 1 st Bullet Pont EPA comment: A review of the labels and supporting residue data indicate that several label amendments are required.

Aventis response: Most of these label amendments have already been made and approved by the EPA.

Page 3 6 th Bullet Point Lines 1 2 EPA comment: Adequate residue data are available on olives provided that use directions for olives are amended to remove the statement allowing the use of summer oil as an adjuvant.

Aventis response: The statement allowing the use of summer oil as an adjuvant has already been deleted from the use directions for olives.

Page: 4 1 st Bullet Point Line 1 EPA comment: Additional data are required depicting carbaryl residue in/ on cotton gin byproducts.

Aventis response: Aventis is not supporting the cotton use and has removed this crop from the labels. Aventis CropScience requested cancellation of this use in a letter to Mr. George Tompkins, RD, on January 22, 1999. A Federal Register Notice dated April 14, 1999 announced receipt by the Agency of an application from RhonePoulenc Ag Company (now Aventis CropScience) to cancel the use of carbaryl products on cotton.

Page: 4 2 nd Bullet Point Lines 1 4 EPA comment: The registrant does not intend to support carbaryl on avocados, barley, maple sap, oats, rye, and sweet sorghum; however, IR 4 has indicated (Correspondence from K. Dorschner, IR 4 Project, 9/ 15/ 94) that they may fulfill the residue data requirements for some of these commodities. These data have not been submitted. 54 Aventis response: IR 4 has not generated the residue data necessary to support these uses. Aventis CropScience will not support these uses.

Page: 4 3 rd Bullet Point Lines 1 2 EPA comment: The reregistration requirements for magnitude of the residue in livestock commodities are not fulfilled. Additional data are required to support dermal and poultry house uses.

Aventis response: Aventis CropScience will neither support dermal nor poultry house uses of carbaryl. A request for cancellation of these uses in accordance with section 6( f)( 1) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) will be submitted shortly to the Agency.

Residue Chemistry Chapter of the Reregistration Eligibility Decision (RED) Document Residue Chemistry Considerations Summary of Science Findings Page 3 Table A1. Carbaryl EPs with Food/ Feed Uses Registered to Aventis Ag Company EPA comment: Label acceptance dates for Carbaryl EPs are listed Aventis response: Label acceptance dates listed for certain products are incorrect. Acceptance dates of the most recently EPA approved labels for SEVIN® 80S, SEVIN® 5% Bait, SEVIN® XLR PLUS, SEVIN® RP2, SEVIN® RP4, SEVIN® 4F, and SEVIN® 80WSP are listed below.

EPA Reg. No. Corrected Label Acceptance Date Product Name 264 316 1/ 13/ 2000 Notification 7/ 26/ 2001 SEVIN® brand 80S Carbaryl Insecticide 264 320 6/ 11/ 1999 SEVIN® brand 5% Bait Carbaryl Insecticide 264 333 2/ 8/ 2001 SEVIN® brand XLR Carbaryl Insecticide (Alternate brand name: SEVIN® brand XLR PLUS Carbaryl Insecticide) 264 334 Notification 10/ 29/ 1999 SEVIN® brand RP2 Carbaryl Insecticide 264 335 10/ 18/ 2000 SEVIN® brand RP4 Carbaryl Insecticide 264 349 1/ 13/ 2000 SEVIN® brand 4F Carbaryl Insecticide 55 264 526 4/ 12/ 2000 SEVIN® brand 80 WSP Carbaryl Insecticide The following SLN Nos are no longer active:

SEVIN® brand 50W: CA830007, NC820007 SEVIN® brand 80S: CA8300007, WA900013 SEVIN® brand XLR: NC960003, OH960003, OR950006, PA960002, VA950001, WA940021 SEVIN® brand 4F: FL890037 Page 3 Paragraph 2 Lines 1 2 EPA comment: Use directions for sugar beets on all labels should be amended to specify a maximum of two applications at a maximum single application rate of 1.5 lb ai/ A and a 28 day PHI.

Aventis response: This change has been made on all Aventis CropScience product labels.

Page 3 Paragraph 3 Lines 1 2 EPA comment: Use directions for sweet corn on the G formulations should be amended to specify a 48 day PHI for stover.

Aventis response: This change has been made.

Page 3 Paragraph 4 Lines 1 2 EPA comment: As the registrant is no longer supporting uses on avocado, the SLN labeling (CA83007) for use of carbary (sic) on avocados in CA should be revoked.

Aventis response: This SLN label has been canceled.

Page 3 Paragraph 5 Line 1 EPA comment: Use directions for cotton on all labels should be amended to remove the 14 day PHI for forage.

Aventis response: The use of carbaryl products on cotton has been canceled. 56 Page 4 Paragraph 1 Lines 1 3 EPA comment: Based on acceptable residue data on okra from IR 4, the registrant should amend use directions on FIC and WP labels to specify a maximum or four applications per season at 1.5 lb ai/ A/ application at a minimum re treatment interval (RTI) of 6 days and a minimum PHI of 3 days.

Aventis response: The current labels allow the application of 1 to 1.5 lb. ai/ A on a 6 to 8 day interval. A maximum of 6 lb ai/ A may be applied per season with a PHI of 3 days.

Page 4 Paragraph 2 Lines 1 2 EPA comment: Use directions for olives on all labels should be amended to remove the statement allowing the use of a tank mix with summer oil.

Aventis response: This change has been made on all Aventis CropScience product labels.

Page 4 Paragraph 3 Lines 1 3 EPA comment: Based on acceptable residue data on prickly pear cactus from IR 4, the registrant should amend use directions on FIC and WP labels to specify a maximum of three applications per season at 2 lb ai/ A/ application at a minimum RTI of 7 days and a minimum PHI of 3 days.

Aventis response: The current labels allow the application of 2 lb ai/ A on a 7 to 10 day interval. A maximum of 6 lb ai/ A may be applied per season with a PHI of 3 days.

GLN 860.1300: Nature of the Residue  Livestock Page 5 Paragraph 4 Lines 2 6 EPA comment: The registrant has stated its intention to support dermal uses on poultry and carbaryl uses in poultry houses and, according to REFS, these uses are on carbaryl labels. If the registrant intends to support these uses of carbaryl on poultry, tolerances, supported by adequate metabolism and magnitude of the residue data, will be required, at levels appropriate for these uses.

Aventis response: Aventis CropScience will no longer support the use of carbaryl for direct application to poultry, as well as the poultry quarters treatment. We will submit a request for cancellation of these uses in accordance with section 6( f)( 1) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). 57 GLN 860.1500: Crop Field Trials Page 9 Paragraph 2 Lines 1 3 EPA comment: Adequate data are available to reassess the tolerances for residues of carbaryl in/ on sugar beet roots and tops provided that use directions on five currently approved labels are modified to allow a maximum of two applications per season at 1.5 lb ai/ A/ application and a PHI of 28 days Aventis response: The labels were amended to conform to these requirements.

Page 10 Paragraph 3 Lines 1 2 EPA comment: Adequate data are available on olives provided that use directions for olives are amended to remove the statement allowing the use of summer oil as an adjuvant.

Aventis response: The labels were amended to conform to this requirement.

Page: 10 Paragraph 5 Lines 2 3 EPA comment: Additional data are required depicting carbaryl residue in/ on cotton gin byproducts.

Aventis response: Aventis is not supporting the cotton use and has removed this crop from the labels.

Page: 10 Paragraph 6 Lines 1 4 EPA comment: The registrant does not intend to support carbaryl on avocados, barley, maple sap, oats, rye, and sweet sorghum; however, IR 4 has indicated (correspondence from K. Dorschner, IR 4 Project, 9/ 15/ 94) that they may fulfill the residue data requirements for some of these commodities. These data have not been submitted.

Aventis response: IR 4 has not generated the residue data necessary to support these uses. Aventis CropScience will not support these uses.

Table A2. Food/ Feed Use Patterns on EP Labels Subject to Reregistration for Carbaryl (Case 0080)

Page: 16 EPA comment: 58 Maximum Single Application Rate, ai: 3.0 lb/ A & 4.0 lb/ A (CA only).

Aventis response: Maximum Single Application Rate, ai: 3.0 lb/ A & 4.0 lb/ A (CA only). An additional application at the dormant or delayed dormant timing may be made at a maximum rate of 5 lb/ A.

Page: 21 Site: Beet, Sugar EPA comment: The maximum seasonal rate for sugar beets is 4.0 lb ai/ A.

Aventis response: The rate for the 80 WSP is 4.0 lb ai/ A. however, the maximum seasonal rate for flowable formulations to sugar beets is 3.0 lb ai/ A.

Page: 23 Site: Broccoli, Brussels sprouts, etc. EPA comment: The preharvest interval for broccoli, Brussel sprouts, cabbage, cauliflower, Chinese cabbage, collards, kale, kohlrabi, and mustard greens is 3 days.

Aventis response: The preharvest interval for broccoli, Brussel sprouts, cabbage, cauliflower, and kohlrabi is 3 days. The preharvest interval for Chinese cabbage, collards, kale, and mustard greens is 14 days.

Page: 26 Site: Citrus fruits EPA comment: The maximum seasonal rate to Citrus Fruits in CA is 20.0 lbs/ A Aventis response: The maximum seasonal rate to Citrus Fruits in CA is 16.0 lbs/ A 59 Part IV  Occupational and Residential Exposure/ Risk Assessment Line by Line Review of the Supporting Document "Carbaryl: Occupational and Residential Exposure Assessment and Recommendations for the Reregistration Eligibility Decision Document (Jeffrey L. aDawson; June 28, 2001)"

1.0 Occupational and Residential Exposure/ Risk Assessment 1.3 Summary of Hazard Concerns Page: 12 Table 1: EPA comment: UF column for short term dermal, inhalation & non dietary ingestion reads "3000 for residential and 300 for occupational"

Aventis response: This box should read, "3000 for residential and 300 for occupational,+ dermal absorption factor" for consistency purposes. However, for the reasons previously stated the extra 10X and 3X MOS factors should be removed due to the recently submitted toxicological studies.

EPA comment: UF column for intermediate term dermal, inhalation & non dietary ingestion reads "1000 for residential and 100 for occupational" and the Type of Exposure column refers only to dermal exposure.

Aventis response: The UF box should read, "1000 for residential and 100 for occupational,+ dermal absorption factor" for consistency purposes. The 1000X MOS factor should be reduced as the extra 10X MOS is no longer necessary. In addition, the Type of Exposure box should read "Intermediate term dermal, inhalation, & non dietary ingestion" for accuracy.

2.0 Occupational Exposures and Risk 2.1.2 Data and Assumptions for Handler Exposure Scenarios Occupational Handler Exposure Studies Page: 34 Paragraph: 3 Note to Chemical Review Managers: EPA comment: " There are no data compensation issues associated with the use of …the propoxur trigger sprayer study has a signed PHED data waiver but just has not been included into PHED at this time. 60 Aventis response: Although Bayer has submitted a data compensation waiver for the inclusion of the propoxur study in PHED, the data compensation waiver is applicable only to the data cited once in PHED. Specifically, the first paragraph of the data compensation waiver form states, `The following pertains only to those data taken from company studies and incorporated into the generic exposure monitoring database'. In addition, the 29 December 1986 memorandum from Douglas Campt, Director of OPP to pesticide registrants regarding the formation of PHED, specifically states on page 2, bullet point 1 Those companies who submit data for inclusion in the data base will waive their compensation rights under FIFRA to the data when referenced generically as part of the data base. However, existing compensation rights will apply when a company's data is cited specifically.

Aventis concludes that the specific referencing of the Bayer propoxur exposure study rather than a PHED generic study number does not eliminate the data compensation rights of Bayer. Aventis believes that the Health Effects Division should seek specific guidance from the Office of General Counsel regarding the data compensation status of the propoxur study for use in the carbaryl RED.

2.0 Occupational Exposures and Risk 2.1.2 Data and Assumptions for Handler Exposure Scenarios Page: 32 Paragraph: First bullet Line 2: EPA comment: If additional information such as average or typical rates are available, these values are used as well in order to allow risk managers to make a more informed risk management decision. Average application rates were available from the SMART meeting and BEAD's QUA. These data indicate that in most cases, average application rates differ from maximum application rates on average by a factor of two. For example, when interpreting the results of the cancer assessment, the small differences generally seen in the available rates should be considered along with the overall magnitude of the cancer risk results.

Aventis response: Aventis believes that the average or typical application rates provided in the document should be used in the determination of intermediate term, chronic, and cancer risk assessments. The use of the label maximum application rates for each application becomes extremely unlikely for intermediate term grower exposure assessments of 10 applications, commercial intermediate term assessments of 30 applications, and chronic or cancer risk assessments. Although the Agency may believe it is obligated to look at the maximum application rates for exposure durations longer than the short term assessments, it should as it states provide 61 estimates of risk based on average application rates for the intermediate term and longer risk assessments. Appendix C provides and utilizes only label maximum application rates for the estimation of intermediate term and chronic MOEs in Tables 3, 4, 5, 6, 8, 9, 10, and 11. The risk assessment must provide MOEs based on average application rates to allow risk managers to make a more informed risk management decision.

2.0 Occupational Exposures and Risk 2.1.2 Data and Assumptions for Handler Exposure Scenarios Page: 42 Table 9: EPA comment: LCO Turfgun exposure estimates obtained from ORETF study OMA002 are based on the wettable powder formulation data. The dermal exposure estimates are 0.99 mg/ lb a. i., 0.72 mg/ lb a. i., and 0.38 mg/ lb a. i. for single layer no gloves, single layer gloves, and double layer gloves clothing scenarios, respectively. Inhalation exposure is 0.062 mg/ lb a. i. The Table 9 footnote states WP formulation used for turfgun assessment as the unit exposures for this scenario were slightly higher than for the other formulations (i. e., well within a factor of 2).

Aventis response: Sevin is sold to the professional lawn care market as either an 80S in water soluble packaging or as the SL liquid formulation. Therefore, the use of the wettable powder formulation is not appropriate. Therefore, the dermal exposure for the single layer of clothing and glove scenario should be 0.66 mg/ lb a. i. based on all formulations and the inhalation exposure should be 0.007 mg/ lb a. i. based on the higher water soluble packaging estimate compared to the flowable liquid inhalation exposure estimate of 0.002 mg/ lb a. i.

2.3 Occupational Risk Characterization 2.3.1 Handler Characterization Page: 103 Paragraph: 2 Line: 19 EPA comment: Where available, average use rates were also used to provide for a more informed risk management decision Aventis response: While Aventis agrees that average use rates should be used for intermediate term and longer repeated exposure risk assessments, the use of average application rates in the exposure assessments does not appear evident. The MOEs presented for intermediate term and longer risk are based on label maximum application rates. The position of Aventis is that handler MOEs for intermediate term and 62 longer risk assessments should be based on average application rates and not label maximum rates as presented in the assessment.

3.0 Residential and Other Non Occupational Exposures and Risks 3.1.1 Handler Exposure Scenarios Page: 116 Table 27: EPA comment: Table 27 states that Hose end sprayer data for mix your own (not the locking/ no contact package) considered.

Aventis response: The dermal and inhalation exposure estimates of 2.61 mg/ lb a. i. and 0.010 mg/ lb a. i., respectively, for the ready to use (RTU) hose end sprayer need to be included in the handler exposure scenario estimations of homeowner exposure during application to lawns. The use of the product in this packaging results in exposure estimates that are different than the dial type sprayer (DTS). Because the RTU sprayer is a significant method of lawn application, the consideration of the potential exposure and risk for lawn applications with the RTU sprayer need to be presented and discussed in the risk assessment. The difference in exposure potential between the DTS and RTU hose end sprayers may provide important information for risk management decisions that are currently lacking.

3.0 Residential and Other Non Occupational Exposures and Risks 3.1.3 Residential Handler Exposure and Non Cancer Risk Estimates Page: 122 Table 28: EPA comment: Scenario 3, Fire Ant MOEs are based on the use of 100 gallons or 0.75 lb a. i./ event for the garden vegetable hose end spray scenario and 5 gallons or 0.0375 lb a. i./ event for garden low pressure handwand applications.

Aventis response: Aventis does not understand why there is a 20 fold difference in the amount of active ingredient handled between the hose end sprayer and hand wand application of carbaryl to control fire ants at the same site, gardens. Aventis believes that the use of 0.0375 lb a. i./ event is reasonable for a vegetable garden and that the use of 100 gallons of spray or 0.75 lb a. i./ A is more representative of a lawn spot application to control fire ants. Scenario 3, Fire ant vegetable garden use should be reduced to 0.075 lb a. i./ event, which is similar to the other scenario 3 vegetable garden uses and consistent with the fire ant control in vegetable gardens using the low pressure hand wand equipment. Any estimation of fire ant 63 control on the lawn should be based on exposure data from the ORETF hose end sprayer exposure study (OMA004) and not from the carbaryl vegetable garden exposure study (MRID 44459801).

3.0 Residential and Other Non Occupational Exposures and Risks 3.1.4 Residential Handler Exposure and Risk Estimates for Cancer Page: 128 Table 29: EPA comment: Presentation of cancer risks to three significant figures.

Aventis response: Aventis does not believe that the expression of cancer risks to three significant figures accurately portrays the lack of precision in the risk assessment. Cancer risks should be presented as either one or two significant figures, consistent with HED policy. The use of three significant figures is leading to the portrayal of cancer risks such as 1.08 x 10 6 for fire ants or 1.24 x 10 6 for vegetable garden dusts as being in excess of the 1 x 10 6 guideline. Both of these risks are more correctly presented as 1 x 10 6 to present the lack of precision in the cancer risk assessment.

Appendix F: Carbaryl Residential Handler Exposure Data Table 2. Input Parameters for Carbaryl Homeowner Handler Exposure and Risk Calculations EPA comment: Inhalation unit exposures are estimated based on a breathing volume of 29 l/ min.

Aventis response: The recommended breathing volume for adult short term exposure is 1.0 m 3 /hr or 17 l/ min for light activities (U. S. EPA Exposure Factors Handbook, Volume 1 General Factors, EPA/ 600/ P 95/ 002Fa). In discussions between the ORETF and the regulatory advisory board to ORETF, it was agreed that application of home pesticide products constituted light activities and that the 17 l/ min breathing rate will be used. The 29 l/ min rate used by HED is the PHED default and represents agricultural work practices that are more strenuous than home pesticide application. Therefore, all residential inhalation exposure estimates should be based on 17 l/ min breathing volume or 59% of the inhalation exposure estimates presented in the HED assessment. 64 Part IV  Occupational and Residential Exposure/ Risk Assessment SUPPORTING DISCUSSION Occupational and Residential Exposure Assessment The assessment of occupational and residential exposure and risk prepared by Mr. Jeff Dawson was a comprehensive assessment of excellent quality. This is reflected by the relatively minimal number of factual error comments provided by Aventis CropScience. Based on the quality of the initial assessment, the major effort regarding the assessment of occupational and residential exposure to carbaryl will involve refinement of the risk assessment.

Aventis CropScience has conducted, or is in the process of conducting, studies relevant to the refinement of the occupational and residential risk assessment. These studies are as follows:

  4 Week Repeated Dose Dermal Toxicity Study with Sevin XLR Plus in Rats. The study is completed and a draft report is currently in review by Aventis. The results of this study are intended to replace the current dermal exposure toxicity endpoints based on oral toxicity used for short term and intermediate term occupational and residential handler exposure when handling liquid formulations of carbaryl. Expected completion date: September 2001   4 Week Repeated Dose Dermal Toxicity Study with Sevin 80S in Rats. The study is completed and a draft report is currently in review by Aventis. The results of this study are intended to replace the current dermal exposure toxicity endpoints based on oral toxicity used for short term and intermediate term occupational and residential handler exposure when handling solid formulations of carbaryl. Expected completion date: September 2001   4 Week Repeated Dose Dermal Toxicity Study with Carbaryl Technical in Rats. The study is completed and a draft report is currently in review by Aventis. The results of this study are intended to replace the current dermal exposure toxicity endpoints based on oral toxicity used for short term and intermediate term occupational and residential postapplication dermal exposure. Expected completion date: September 2001   Measurement of Pesticide Exposure of Suburban Residents Associated with the Residential Use of Carbaryl. This is an ongoing biological monitoring study of 10 families in California and 10 families in Missouri. The study will monitor the absorbed dose of carbaryl resulting from a lawn broadcast application and subsequent vegetable garden application of carbaryl by an adult family member. Postapplication absorbed dose of all adults and children aged four to seventeen will be followed over a three day period. The participants' postapplication activities will be recorded but not controlled to establish a range of absorbed 65 doses. The data will be used along with the residential exposure assessment to improve understanding of residential exposure to carbaryl. Expected completion date: March 2002   University of California  Riverside biological monitoring of citrus orchard application and postapplication apple thinning and cherry harvesting job functions is completed in the field. The results from these studies will be used to refine the PHED and ARTF based exposure estimates. These are high exposure potential work functions and the biological monitoring data are intended to refine the assessments of these work functions. Expected completion date: March 2002 66 APPENDIX I Business Confidential Surface Water Monitoring for Residues of Carbaryl in High Use Areas of the United States (Stone Environmental, Inc. Report #99 1005 F) (hard copy provided) 1 CARBARYL PC Code No. 056801; Case 0080 Review of the Draft Environmental Fate and Ecological Risk Assessment for the Reregistration of Carbaryl August 6, 2001 Aventis CropScience P. O. Box 12014, 2 T. W. Alexander Drive Research Triangle Park, NC 27709 2 CARBARYL PC Code No. 056801; Case 0080 Review of the Draft Environmental Fate and Ecological Risk Assessment for the Reregistration of Carbaryl TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................................... 2 GENERAL COMMENTS .................................................................................................................... 5 TRANSMITTAL DOCUMENT ............................................................................................................ 9 Data Gaps ............................................................................................................................... 9 Environmental Fate and Transport ............................................................................... 9 Water Resources ........................................................................................................... 9 Ecological Effects Data requirement .......................................................................... 10 Label Information ....................................................................................................... 11 DRAFT RED DOCUMENT .............................................................................................................. 13 1.0 Summary and Environmental Risk Conclusions ........................................................... 13 Risk to Terrestrial Organisms ..................................................................................... 13 Fate and Water Assessment ........................................................................................ 13 2.0 Introduction .................................................................................................................... 14 3.0 Integrated Risk Characterization ................................................................................... 15 Introduction ................................................................................................................. 15 Aquatic Organisms ...................................................................................................... 15 Terrestrial Organisms ................................................................................................. 16 Endocrine Disruption Concerns .................................................................................. 18 Uncertainties ............................................................................................................... 19 4.0 Environmental Fate Assessment .................................................................................... 20 Exposure Characterization .......................................................................................... 20 Persistence .................................................................................................... 23 Mobility ........................................................................................................ 24 Field Dissipation ........................................................................................... 25 Foliar Dissipation ......................................................................................... 27 Atmospheric Transport ................................................................................. 28 1 Naphthol Fate and Transport ..................................................................... 28 Aquatic Exposure Assessment .................................................................................... 30 Surface Water ............................................................................................... 30 Estimated Environmental Concentrations for Terrestrial Ecological Risk Assessment32 5.0 Drinking Water Assessment .......................................................................................... 32 Water Resources Assessment ..................................................................................... 32 Drinking Water Exposure Assessment ......................................................... 33 Water Treatment Effects .............................................................................. 37 Ground Water Resources .............................................................................. 38 3 Surface Water Resources .............................................................................. 39 6.0 Hazard and Risk Assessment for Aquatic Organisms .................................................. 45 Hazard assessment for Aquatic organisms ................................................................. 45 Estuarine/ Marine Fish .................................................................................. 45 Aquatic Plants ............................................................................................... 45 Risk Assessment for Aquatic Organisms .................................................................... 45 Estuarine/ Marine Fish .................................................................................. 46 7.0 Hazard and Risk Assessment for Terrestrial Organisms .............................................. 46 Hazard Assessment for Terrestrial Organisms ........................................................... 46 Mammalian ................................................................................................... 46 Risk Assessment for Terrestrial Organisms ................................................................ 46 Avian Risk .................................................................................................... 46 Mammalian Risk .......................................................................................... 47 Reproduction Effects .................................................................................... 48 9.0 References (non MRID) ............................................................................................... 50 Appendix A: Environmental Fate Study Reviews (DERs) ................................................. 50 Appendix B: Refined Water Memo .................................................................................... 50 Appendix C: Ecological Risk Assessment .......................................................................... 51 Toxicity Endpoints Used in the Risk Assessment ...................................................... 51 Avian Acute and Chronic Risk ................................................................................... 51 Risk from Exposure to Non granular Products ........................................................... 52 Risk from Exposure to Granular Products .................................................................. 52 Aquatic Plants ............................................................................................................. 52 Appendix D: Toxicity Assessment ...................................................................................... 52 Birds, Chronic Toxicity .............................................................................................. 53 Mammals, Acute and Chronic .................................................................................... 53 Freshwater Fish, Acute ............................................................................................... 54 Freshwater Invertebrates, Acute ................................................................................. 54 Estuarine and Marine Invertebrates, Acute ................................................................. 54 DISCUSSION ............................................................................................................................. 56 1. Surface Water Concentrations ........................................................................................ 56 Summary of Registrant Surface Water/ Drinking Water Monitoring Program ........... 56 Summary of Surface Water Data from the NAWQA Program .................................. 58 Summary of Carbaryl Analytical Methods used in the NAWQA Program ................ 60 Gas Chromatography/ Mass Spectroscopy Method ...................................... 60 High Performance Liquid Chromatography/ Photodiode Array Method ..... 64 Summary of Surface Water Data from the California DPR Surface Water Database 64 2. Ground Water Concentrations ........................................................................................ 66 Summary of Ground Water Data from the NAWQA Program .................................. 66 REFERENCES ............................................................................................................................ 68 4 TABLE OF CONTENTS (continued)

Tables Table 1. Summary Of Results From The Carbaryl Drinking Water Monitoring Study. 57 Table 2. Carbaryl Detections Reported In Pesticides In Streams Update (Larson, 2001) ........................................................................................................... 58 Table 3. Frequency Of Carbaryl Detections By GC/ MS In Different Concentration Ranges Reported In The NAWQA Database As Of July 16, 2001 ............ 59 Table 4. Frequency Of Carbaryl Detections By LC/ PDA In Different Concentration Ranges Reported In The NAWQA Database As Of July 16, 2001 ............ 59 Table 5. Recovery And Precision For Multiple Determinations Of Carbaryl In GC/ MS Method For Carbaryl Spiked In Different Water Samples ............ 61 Table 6. Percent Recoveries Of Carbaryl Detected By The NAWQA GC/ MS Method In Laboratory Control Spikes And Field Matrix Spikes At A Spiking Level Of 0.1 µ g/ L ................................................................................................. 63 Table 7. Recovery And Precision For Multiple Determinations Of Carbaryl In LC/ PDA Method For Carbaryl Spiked In Different Water Samples .......... 64 Table 8. Carbaryl Detections Reported In California DPR Surface Water Monitoring Database ...................................................................................................... 65 Table 9. Limits Of Quantification For Carbaryl Analytical Methods Reported In California DPR Surface Water Monitoring Database ................................. 65 Table 10. Carbaryl Detections Reported In Pesticides In Ground Water Update (Kolpin, 2001) ............................................................................................. 67 Confidential Business Attachments APPENDIX 1 .............................................................................................................................. 70 APPENDIX 2 .............................................................................................................................. 71 The last page of this report is number 70 \# "0" 70. 5 General Comments The EFED draft chapter of the carbaryl RED is very thorough using a wealth of references. The use of published literature over submitted data is significant. The quality of the published literature is at times at least questionable and other times does not fulfill the requirements set by EPA for studies submitted by the registrant (e. g. thorough description of test conditions, clear identification of the test material, analytical verification, GLP etc.). Data of such poor quality should not be used as key information in the risk assessment. For the 30 day response not all literature references could be verified or the quality ascertained.

There is a high level of redundancy in the document making it difficult to read. Reducing repetitions to a minimum would facilitate the reading.

We believe it is inappropriate to include DERs in the RED Chapters. A summary of study findings is already presented in the document. DERs should be made available to the public through the regular procedure under the Freedom of Information Act after they have been reviewed and cleared for confidential business information.

The use of carbaryl on barley, oats, rye, cotton, and livestock are cancelled . It should be noted that Aventis CropScience labels for the technical materials and the end use products containing carbaryl were amended to delete these uses. The Agency has already approved the labeling changes (please refer to HED response document, Section III for details).

Aventis CropScience will no longer support the use of carbaryl on poultry (direct application and poultry quarters treatment). We will shortly submit a request for cancellation of these uses in accordance with section 6( f)( 1) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) (please refer to HED response document, Section III for details).

Aventis CropScience is in the process of conducting, or has scheduled, studies relevant to the refinement of the environmental risk assessments for carbaryl and the major degradate 1 naphthol. These studies are as follows:

  Rate and Route of Aerobic Degradation in Soils. These studies have been initiated with parent carbaryl applied to four diverse U. S. soils. The data are intended to provide additional half life determinations for parent carbaryl and the major degradate 1 naphthol. Expected completion date: March 2002   Aerobic Aquatic Metabolism in Two Water/ Sediment Systems. These studies have been initiated with parent carbaryl applied to two distinct U. S. water/ sediment systems. The data are intended to provide additional half life determinations for parent carbaryl and the major degradate 1 naphthol. In addition, further identification of additional degradation products is anticipated. Expected completion date: March 2002   Adsorption and Desorption of 1 Napthol to five soils. This study has been scheduled to evaluate the adsorption and desorption of the major carbaryl degradate to five soils/ sediment. The data are intended to provide information necessary to evaluate the 6 environmental risks from 1 naphthol in standard models. Expected completion date: March 2002 For the reregistration process in the EU, Aventis CropScience is in the process of conducting, or has scheduled, studies relevant to the refinement of the ecotoxicological risk assessments for carbaryl and the major degradate 1 naphthol. These studies are as follows:

  Studies with Carbaryl: Acute oral LD50 in mallard ducks Dynamic acute LC50 in bluegill sunfish Acute toxicity in Daphnia Acute toxicity in Chironomus riparius Toxicity in Selenastrum capricornutum Acute oral and contact toxicity in honeybees 14 d toxicity in earthworms Effects on soil microorganisms (nitrification/ carbon cycle) Effect on sewage treatment   Studies with 1 naphthol Early life stage study in fathead minnow Acute toxicity in Daphnia Acute toxicity in Daphnia in presence of sediment Chronic toxicity in Daphnia 14 d toxicity in earthworms   Formulated Product Vegetative Vigor Toxicity in Selenastrum capricornutum Acute oral and contact toxicity in honeybees Effect on non target arthropods 14 d toxicity in earthworms Effects on soil microorganisms (nitrification/ carbon cycle)

Ecotoxicological Risk Assessments Aventis has pointed out several errors in the PRZM input parameters (see comments made to Tables 5 and 6 of the draft RED), overly conservative estimates of foliar dissipation half lives and changes in ecotoxicology study endpoints. This indicates that a re calculation of the EECs and risk quotients are warranted in a number of instances.

Endocrine Disruption Reports in the open literature on the reproductive effects of carbaryl in wild mammals are at best ambivalent. The recently submitted 2 generation study in rats demonstrates the absence of 7 reproductive effects. As EPA pointed out, findings reported in the literature were made at concentrations well above the highest peak concentration modeled. Therefore these findings are irrelevant for a risk assessment and at the current stage of discussion about endocrine disruption. If the concern about the endocrine potential of carbaryl persists, the issue should be revisited once the Agency's endocrine disrupter screening and testing program as well as a policy on how to incorporate positive findings into an ecological risk assessment have been fully developed.

Mobility The classification of carbaryl as mobile to very mobile is inconsistent with measured Koc values of 177 to 249 (MRID 43259301). According to the widely used classification scheme of McCall, et al. (1980) wherein Koc values between 150 and 500 denote medium mobility in soil, carbaryl would be classified as having medium mobility in most soils. This classification of medium mobility is further supported by the acceptable column leaching study (MRID 43320701) in which aged carbaryl residues were only slightly mobile in a number of soils. The mobility of carbaryl would be expected to be higher in sandy soils or in soils of low organic matter.

1 Napthol Fate and Transport The Agency is requiring additional information on the persistence and mobility of 1 naphthol, a major environmental degradate of carbaryl. However, a half life for 1 naphthol of less than 1 day can be calculated from the carbaryl aerobic soil metabolism study (MRID 42785101). The data from this study demonstrate that under aerobic soil conditions the formation and decline of 1 naphthol, starting from parent carbaryl, is complete in less than 14 days. This half life can be used for preliminary environmental fate modeling to estimate EECs for 1 naphthol.

The EPA suggested that 1 naphthol is not strongly sorbed to soil. Additional information available in the literature demonstrates that the sorption of 1 naphthol to soil is stronger than that seen for carbaryl itself. Hassett et al. (1981) has demonstrated that the sorption of 1 naphthol was the result of sorption to organic carbon resulting in Koc values between 431 and 15,618. These data indicate that 1 naphthol is less mobile and less susceptible to leaching than carbaryl itself, and they demonstrate that at least a portion of the 1 naphthol residue is tightly sorbed to soil constituents. (A copy of this article is being submitted with the response to the draft RED.) To meet the requirement for information on the adsorption and desorption of 1 naphthol by the Agency, the registrant is conducting an adsorption/ desorption study to meet the 163 1 guideline. Study results should be available for submission to the Agency in the first quarter of the calendar year 2002.

Surface Water/ Drinking Water Aventis disagrees with EPA that the modeling simulations provide a conservative, though not unreasonable, estimate on possible concentrations in drinking water. Drinking water concentrations derived from PRZM/ EXAMS greatly overestimate the potential exposure to carbaryl in drinking water, generally by several orders of magnitude. Results from the drinking 8 water monitoring program conducted by the registrant provides a `real world' assessment of the potential for human exposure to carbaryl in drinking water derived from surface water.

Ground Water EPA summarized information on the detection of carbaryl in groundwater from the EPA Pesticides in Groundwater Database, the EPA STORET database and the NAWQA database. Each of the databases shows a pattern of very low levels of carbaryl detection in few groundwater resources. These analyses confirm several statements made by the Agency that carbaryl have limited potential to impact groundwater resources. However, on page 2 of the Memorandum issued June 28, 2001, in conjunction with the EFED RED chapter for carbaryl, EPA is requiring additional information on "Surface and groundwater monitoring in urban and suburban use areas (non guideline)." Based on the characteristics of carbaryl and the available data demonstrating limited impact of carbaryl on ground water resources, additional studies to evaluate the potential for carbaryl to contaminate groundwater are unnecessary and unwarranted. 9 Line by Line Review of the Carbaryl EFED RED Chapter Transmittal Document Data Gaps Environmental Fate and Transport Page: 2 Paragraph: 1 Line: 1 EPA comment: Fate information on the degradation product 1 naphthol is required.

1. Mobility – adsorption and desorption studies for the 1 naphthol degradate (163 1) 2. Persistence – aerobic soil metabolism study on 1 naphthol Aventis' response: Literature data (Hassett et al. 1981) on the adsorption of 1 naphthol are provided in this response. Aventis is in the process of conducting an additional adsorption/ desorption study on 1 naphthol and intends to submit study data to EPA by March 2002.

The degradation of 1 naphthol under aerobic soil conditions has been widely reported in the literature. Several citations are included in the EPA draft RED. The half life of 1 naphthol estimated from the acceptable aerobic soil persistence study on carbaryl (MRID 42785101) is less than 1 day. Aventis is conducting additional laboratory aerobic soil degradation studies on carbaryl that will be used to provide additional determinations of the half life for the degradate 1 naphthol and satisfy the Agency's requirement for data on the persistence of 1 naphthol. Aventis intends to submit these study data to EPA by March 2002.

Water Resources Page: 2 Paragraph: 3 and 4 EPA comment: "EFED believes that adequate data are available to support the conclusions reached for carbaryl's impact on surface water and groundwater quality with the exceptions noted below. Additional information is needed to characterize the impact of the degradate 1 naphthol [in] groundwater and surface water.   Surface and groundwater monitoring in urban and suburban use areas (non guideline)" are required. 10 Aventis' response: The surface water monitoring program conducted by Aventis includes monitoring in urban and suburban use areas. Aventis believes that the need for information on the degradate 1 naphthol will be satisfied by the aerobic soil and adsorption/ desorption data that will be submitted to the Agency. These data can be used to evaluate the availability of 1 naphthol using established EPA modeling guidelines. The Agency's proposed requirement for groundwater monitoring is unnecessary and is addressed in Aventis' response to Agency comments in the draft RED.

Ecological Effects Data requirement Page: 2 EPA comment: The ecological toxicity database is complete except for: 6. Aquatic Plant Growth Guideline 122 2 Aventis' response: The data requirement should be deleted. Aquatic plant growth studies were submitted to the Agency in 1992. An October 04, 2000 OPP Guideline Status Report (Chemical Review Management System) lists the guideline 122 2 status as "Acceptable/ Satisfied". The studies are:

MRID No. Title Acceptability Code 42372101 Lintott, D. (1992) Carbaryl Technical: Acute Toxicity To The Freshwater Blue Green Alga, Anabaena flos aquae, Under Static Test Conditions: Lab Project Number: J9112004E. Unpublished Study Prepared By Toxikon Environmental Sciences. 53 P. June 25, 1992 Upgradable 42372102 Lintott, D. (1992) Carbaryl Technical: Acute Toxicity To Duckweed, Lemna gibba G3, Under Static Test Conditions: Lab Project Number: J9112004G. Unpublished Study Prepared By Toxikon Environmental Sciences. 53 P. January 1, 1992 Upgradable 42372802 Lintott, D. (1992) Carbaryl Technical: Acute Toxicity To The Freshwater Green Alga, Selenastrum capricornutum Under Static Conditions: Lab Project Number: J9112004C. Unpublished Study Prepared By Toxikon Environmental Sciences. 53 P. June 9, 1992 Acceptable 42431601 Lintott, D. (1992) Carbaryl Technical: Acute Toxicity To The Freshwater Diatom, Navicula pelliculosa, Under Static Test Conditions: Lab Project Number: J9112004F. Unpublished Study Prepared By Toxikon Environmental Sciences. 52 P. August 10, 1992 Acceptable 42431602 Lintott, D. (1992) Carbaryl Technical: Acute Toxicity To The Saltwater Diatom, Skeletonema costatum, Under Static Test Conditions: Lab Project Number: J9112004D. Unpublished Study Prepared By Toxikon Environmental Sciences. 49 P. August 10, 1992 Supplemental 11 Page: 2 EPA comment: The ecological toxicity database is complete except for: 7. Submission of a FETOX amphibian toxicity study is required. Aventis' response: The data requirement should be deleted. From the published results it is evident that carbaryl is practically non toxic to the bullfrog. Effects in plain leopard frogs are reported at levels well above environmental concentrations. These results were obtained testing U. S. native species. In the proposed FETOX assay, a non native species Xenopus laevis is used. This African species is unique in its behavior. Neither the species nor the test methods are suitable for ecotoxicological purposes. As the risk to amphibians can be evaluated from the studies cited, and as the effects are only at levels well above the EEC, this study should not be required.

Label Information Page: 3 EPA comment: For terrestrial and residential uses: 1. "Do not apply directly to water, or to areas where surface water is present or to intertidal areas below the mean high water mark. Do not contaminate water when disposing of equipment washwater or rinsate." Aventis' response: Similar language is already present on Aventis' SEVIN® labels.

Page: 3 EPA comment: For terrestrial and residential uses: 3. "This product may contaminate water through drift of spray in wind. This product has a high potential for runoff for several days after application after application (sic). Poorly draining soils and soils with shallow water tables are more prone to produce runoff that contains this product.

Household labels – Avoid applying this product to ditches, swales, and drainage ways. Runoff of this product will be reduced by avoiding applications when rainfall is forecasted to occur within 48 hours.

Agricultural Label – A level, well maintained vegetative buffer strip between areas to which this product is applied and surface water features such as ponds, streams, and springs will reduce the potential for contamination of water from rainfall runoff. Runoff of this product will be reduced by 12 avoiding applications when rainfall is forecasted to occur within 48 hours." Aventis' response: Aventis would like to further discuss appropriate label language with the Agency. However, it should be noted that light to moderate rainfall (or irrigation) after application will also help move carbaryl residues deeper into the soil, thus making them less susceptible to runoff. The language in the last sentence should be changed to read, "… when heavy rainfall is….".

Page: 3 EPA comment: For terrestrial and residential uses: 4. This pesticide is toxic to fish and aquatic invertebrates. Aventis' response: Aventis' SEVIN labels currently state "This product is extremely toxic to aquatic and estuarine invertebrates."

Page: 3 EPA comment: For terrestrial and residential uses: 5. This product is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are visiting the treatment area. Aventis' response: Aventis' SEVIN labels currently contain similar language. 13 Draft RED Document 1.0 Summary and Environmental Risk Conclusions Risk to Terrestrial Organisms Page: 1 Paragraph: 4 Line: 2 EPA comment: As discussed in pp. 44  45 and in Appendix D. Aventis' response: The mammalian risk quotients are discussed on pages 48 to 50 and in Appendix C, not as described in this text.

Fate and Water Assessment Page: 3 Paragraph: 5 Line: 3 EPA comment: …in the U. S. G. S NAQWA program. NAQWA… Aventis' response: The abbreviation for the U. S. G. S. program is NAWQA Page: 5 Paragraph: 1 Line: 7 EPA comment: …estimate of possible concentrations drinking water. Aventis' response: missing word – …concentrations "in" drinking… Page: 5 Paragraph: 4 Line: 4 EPA comment: …hydrolyzes in neutral (half life = 12 days) and alkaline environments (pH 9 half life = 3.2). Aventis' response: Missing units of after second half life. The units are hours, so "= 3.2 hours)".

Page: 5 Paragraph: 4 Line: 5 EPA comment: …photolysis in water with a half life of 21 days 14 Aventis' response: this is for photolysis in sterile water, not microbially active water, so the phrase would be more precise as "… photolysis in sterile water…".

Page: 5 Paragraph: 4 Line: last EPA comment: (Kf =1.7 to 3.2). Aventis' response: The upper value Kf for carbaryl should be listed as 3.5 as referenced by EPA elsewhere (e. g. Table 3, page 20) in the document.

2.0 Introduction Page: 6 Paragraph: 2 Line: 1 3 EPA comment: Carbaryl (1 naphthyl N methylcarbamate) is a broad spectrum carbamate insecticide and acaricide registered for control of over 300 species of insects and mites on over 100 crop and noncrop use sites, including homeowner uses; pet, poultry, and livestock uses;… Aventis' response: Carbaryl is no longer registered for use on livestock. Aventis CropScience will not support the reregistration of the use on poultry (direct application and poultry quarters treatment). We will shortly submit a request for cancellation of this use in accordance with section 6( f)( 1) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).

Page: 6 Paragraph: 3 Line: 2 3 EPA comment: Approximately 2.5 million pounds of carbaryl are applied annually in the U. S. A map showing the widespread use of carbaryl in agriculture is shown in figure 1. Aventis' response: Summation of the data in Figure 1 gives a total of approximately 3.3 million pounds of carbaryl. Both the 2.5 and 3.3 million pound figures are inconsistent with the value of 4 million pounds cited on page 35. The 2.5 million pounds is an average of usage over 1987 to 1996 developed in a memo by Frank Hernandez, July 21, 1998. The value of 2.5 million pounds in the text should be qualified with the additional information on the fact that it is an average for usage over 1987 to 1996 and is not a value for a single year.

Page: 7 Paragraph: 1 Line: 3 4 15 EPA comment: Carbaryl is also used extensively for residential and other non agricultural uses, being the second most commonly insecticide (sic) used in the home. Aventis' response: Carbaryl is not registered for use inside homes. It is registered for use outdoors in the lawn and garden around homes. In addition, an evaluation of the Vista (Triad) data for the last seasonal year from October 1999 to September 2000 shows retail sales for carbaryl at 18.7 million dollars. Carbaryl is listed as number 7 based on retail sales behind other active ingredients such as chlorpyrifos, diazinon, imidacloprid, hydramethylnon and tralomethrin. Therefore this sentence would be more appropriately worded as: "Carbaryl is also used for residential and other non agricultural uses, being the seventh most commonly used insecticide around the home."

Page: 7 Figure 1 EPA comment: Figure 2 Aventis' response: This is labeled as Figure 2 when it is Figure 1 3.0 Integrated Risk Characterization Introduction Page: 8 Paragraph: 1 Line: last EPA comment: Carbaryl is mobile to very mobile in the environment (Kf =1.7 to 3.2). Aventis' response: The upper value Kf for carbaryl should be listed as 3.5 as referenced by EPA elsewhere (e. g. Table 3, page 20) in the document. The classification of carbaryl as mobile to very mobile is inconsistent with measured Koc values of 177 to 249. According to the widely used classification scheme of McCall et al. carbaryl would be classified as having medium mobility in soil. This classification of medium mobility is further supported by the acceptable column leaching study (MRID 43320701) in which carbaryl residues were only slightly mobile in a number of soils.

Aquatic Organisms Page: 10, Paragraph: 1, Line: 13 EPA comment: Submission of a FETOX amphibian toxicity study is encouraged. Aventis' response: 16 The data requirement should be deleted. From the published results it is evident that carbaryl is practically non toxic to the bullfrog. Effects in plain leopard frogs are reported at levels well above environmental concentrations. These results were obtained testing U. S. native species. In the proposed FETOX assay a non native species Xenopus laevis is used. This African species is unique in its behavior. Neither the species nor the test methods are suitable for ecotoxicological purposes. As the risk to amphibians can be evaluated from the studies cited, and as the effects are only at levels well above the EEC, this study should not be required.

Page: 10, Paragraph: 3, Line: 6/ 7 EPA comment: …resulting in a temporary impairment of burying behavior and increasing exposure to predators. Aventis' response: A reference for this statement should be added.

Page: 11, Paragraph: 2, Line: 7 EPA comment: In a mesocosms study, at carbaryl… Aventis' response: Typographical error. Change to "In a mesocosm study, at carbaryl…"

Terrestrial Organisms Page: 12 Paragraph: 2 EPA comment: (use of rock dove LD50 ) Aventis' response: The reference cited for this value in Table 1 of Appendix D is currently not available to Aventis. Table 1 of Appendix D gives a range of 1000 – 3000 mg/ kg for the LD50. It should be assured that 1000 is indeed the correct value.

Page: 12 Paragraph: 3 Line: 3  6 EPA comment: On a chronic basis, the NOAEC is 300 ppm for the mallard duck, based on adverse reproduction effects, including reduced egg production, decreased fertility, increase incidence of cracked eggs, increased embryonic mortality, and reduced hatching success. Aventis' response: The sentence should be changed. The embryonic mortality and the hatching success were not different from the control. 17 Page: 13 Paragraph: 1 Line: 1 EPA comment: …( rat LD50 = 307 mg/ kg) Aventis' response: Typographical error, the LD50 is 301 mg/ kg.

Page: 13 Paragraph: 1 Line: 2 – 4 EPA comment: …based on decreased fetal body weights and increased incomplete ossification of multiple bones in the laboratory rat (LOAEC = 600 ppm, NOAEC = 80 ppm), has the potential for mammalian chronic effects. Aventis' response: A new chronic reproduction study in rats has been submitted by Aventis. This study is more relevant for an ecological risk assessment than the developmental study cited. The new study resulted in a NOAEC of 75 ppm.

Page: 13 Paragraph: 3 Line: 1 EPA comment: Information available in the open literature suggests potential reproduction effects of carbaryl on mammals. Aventis' response: The sentence should be changed or deleted. The literature cited in the paragraph show ambivalent results. While some references seem to support that sentence, other references do not substantiate such a claim. The potential for reproductive effects in mammals is evaluated in the recently submitted 2 generation study in rats. No reproductive effects were seen in that guideline study. The NOAEC of 75 ppm was based on pup mortality.

Page: 13 Paragraph: 4 Line: 5 EPA comment: According to surveys conducted by the American Beekeeping Federation and the Washington State Department of Agriculture, carbaryl is one of the pesticides most frequently mentioned as being associated with bee kills. Aventis' response: A reference should be provided for this statement. 18 Page: 14 Paragraph: 4 Line: 1 4 EPA comment: The uses of carbaryl on crops (corn, cotton, soybeans, sorghum, wheat, barley, oats, and rye), forests and pasture/ rangeland were addressed by the US Fish and Wildlife Service (USFWS) in the reinitiation of consultation in September 1989. The Service found jeopardy to a total of 86 species – 6 amphibians, 47 freshwater fish, 27 freshwater mussels, and 5 aquatic crustaceans. Aventis' response: The use of carbaryl on barley, oats, rye, and cotton has been cancelled. It should be noted that all Aventis CropScience labels for the technical materials and the end use products containing carbaryl were amended to delete these uses. The Agency has already approved the labeling changes. Findings from the assessment made by the USFWS should be reevaluated considering the cancellation of the use on barley, oats, rye, and cotton.

Page: 14 Paragraph: 5 Line: 7 EPA comment: The RPAs and RPMs in the 1989 B. O. may need to be reassessed… Aventis' response: The acronyms used should be explained.

Endocrine Disruption Concerns Page: 15 Paragraph: 3 EPA comment: (Report on potential endocrine effects) Aventis' response: The paragraph should be deleted. As EPA pointed out, the findings reported in the literature were made at concentrations well above the highest peak concentration modeled. Therefore these findings are irrelevant for a risk assessment and at the current stage of discussion about endocrine disruption. If the concern about the endocrine potential of carbaryl persists, the issue should be revisited once the Agency's endocrine disrupter screening and testing program, as well as a policy on how to incorporate positive findings into an ecological risk assessment have been fully developed.

Page: 15 Paragraph: 4 EPA comment: Furthermore, a number of field and laboratory studies report reproduction effects with mammals, suggesting that the possibility of endocrine disruption effects on wild mammals should be further examined. 19 Aventis' response: The statement should be deleted or modified. As pointed out above, reports on reproductive effects of carbaryl in the open literature are at least ambivalent. The recently submitted 2 generation study in rats demonstrated the absence of reproductive effects. If the general statement about the potential for endocrine disruption of carbaryl is maintained, references (or a cross reference within the document) for the above claim should be provided.

Uncertainties Page: 15 Paragraph: Last Line: 4 EPA comment: In the absence of a valid two generation rat reproduction study, mammalian chronic RQs were based on a rat prenatal development study NOAEC (MRID# 44732901). Aventis' response: A new two generation study in rats was recently submitted. 20 4.0 Environmental Fate Assessment Exposure Characterization Page: 16 Paragraph: 3 Line: 8 EPA comment: Environment (Kf =1.7 to 3.2). Aventis' response: The upper value Kf for carbaryl should be listed as 3.5 as referenced by EPA elsewhere in the document (e. g. Table 3, page 20).

Page: 16 Paragraph: 3 Line: last sentence EPA comment: Detailed discussion and reviews (DERs) of the studies that are included in this assessment are attached in Appendix A. Aventis' response: It is inappropriate to include the DERs in the RED. A summary of study findings is already included in the EFED Chapter. DERs should be made available to the public through the regular procedure under the Freedom of Information Act after they have been reviewed and cleared for confidential business information.

Page: 16 Paragraph: 4 Line: 4 EPA comment: lower levels (generally less than 0.01 : /L). Aventis' response: value missing units  (generally less than 0.01 : g/ L).

Page: 16 Paragraph: 5 Line: 4 EPA comment: …monitoring data is of limited utility in developing EECs for ecological and human health risk assessment. Aventis' response: The drinking water monitoring program conducted by the registrant provides a real world assessment of the potential for human exposure to carbaryl in drinking water derived from surface water. Drinking water concentrations derived from PRZM/ EXAMS greatly overestimate the potential exposure to carbaryl in drinking water, generally by several orders of magnitude. 21 Page: 17 Paragraph: 1 Line: 2 3 EPA comment: The maximum rate was taken from the carbaryl labels. Aventis' response: It would be of benefit for the Agency to be explicit and list the carbaryl labels that were used to develop the maximum application rates for the model scenarios. The reference cited in the EFED Chapter regarding the use of carbaryl on crops indicate that current labels were not used for the Agency's assessment. Many of these crops have been deleted from Aventis' labels for a few years Application rates, number of applications per season, and PHI's also have changed for several crops on the labels.

Page: 17 Paragraph: 2 Line: 2 EPA comment: For the Index Reservoir scenario using maximum label rates, acute EEC values ranged from about 10 : g/ L from sugar beets to about 500 : g/ L from citrus (Table 6). Aventis' response: Table 6 on page 33 shows a concentration of 19 : g/ L for sugar beets treated with the maximum label rate of 2 x 1.5 lb ai, not 10 as stated in this sentence. A low EEC value of 9 : g/ L for sugar beets results from the "maximum reported" application scenario of 1 x 1.2 lb ai/ A.

Page: 17 Paragraph: 2 Line: 3 EPA comment: Chronic EECs ranged from about 1 to 28 : g/ L. Aventis' response: Table 6 on page 33 shows that this is correct when considering all of the model scenarios. However, either the same maximum label rate reference should be used as in the preceding sentence (in which case the minimum chronic EEC would be 2), or the basis for the preceding sentence should be changed from the maximum label rate to include all application scenarios to keep the comparisons consistent.

Page: 17 Paragraph: 2 Line: 8 EPA comment: The results of the modeling provide an (sic) conservative, though not unreasonable, estimate on (sic) possible concentrations [in] drinking water. Aventis' response: It should be clear that Aventis' surface water monitoring program provides a more reasonable estimate of the potential drinking water exposure to carbaryl than the modeling numbers, which overestimate exposure by several orders of magnitude. 22 Page: 17 Paragraph: 2 Line: last EPA comment: …and model input and output files are attached in appendix B. Aventis' response: The PRZM input files for only the Index Reservoir drinking water modeling were provided as an electronic copy. The PRZM input files for the standard pond scenarios were not provided in the draft RED so Aventis could not assess the data. None of the output files were provided.

Page: 18 Figure 2 EPA comment: Figure 1. Generalized carbaryl degradation pathway Aventis' response: This should be labeled Figure 2, not Figure 1.

Page: 19 Table 3 EPA comment: Hydrolysis half life at pH 9 stated to be 5 hours. Aventis' response: The study results, and the summary of the study presented on page 20, show the correct half life at pH 9 to be 3.2 hours.

Page: 19 Table 3 EPA comment: Aerobic Aquatic half life  4.9. Aventis' response: The Aerobic Aquatic half life is 4.9 days Page: 19 Table 3 EPA comment: Soil metabolism T1/ 2, anaerobic, assumed stable 23 Aventis' response: If this guideline is satisfied by the data submitted for guideline 162 3, it is not clear why the compound is assumed to be stable rather than having a half life in line with the 72 days that resulted from the anaerobic aquatic study. Although this parameter plays a fairly insignificant role in estimating the amount of carbaryl available for runoff in the models, it could play a significant role if one were to use this value in estimating leaching potential in subsurface horizons.

Page: 20 Table 3 EPA comment: Batch Equilibrium 1/ n values ranged from 0.86 1.02 Aventis' response: These values are for the desorption isotherms only. For the adsorption isotherms that were used to calculate the adsorption Kf and Koc values listed in the table, the correct range of 1/ n values are 0.78 to 0.84 as stated on page 22.

Page: 20 Table 3 EPA comment: Foliar Dissipation 30 days Willis and McDowell, 1987 Aventis' response: The foliar dissipation half life listed by EFED is incorrect. Table IV of the Willis and McDowell review lists 10 foliar half lives for various formulations of carbaryl applied to different crops. Five of these half lives are for a study designed to evaluate a new analytical procedure for measuring carbaryl residues on plants. This study was conducted on plants grown in a greenhouse, with some of them receiving an unknown amount of simulated rainfall. These studies on greenhouse grown plants should not be used to evaluate foliar persistence in the field. The foliar persistence of pesticides can be considerably different for residues on and in plants grown in greenhouses versus the field. Eliminating the half lives for the greenhouse grown plants results in the following half lives for carbaryl on field plants: Cotton, 1.2, 1.3, 1.5 days; strawberry, 4.1 days; tomato 1.4 days. Therefore, the longest half life of 4.1 days should be listed in this table.

Aventis intends to conduct a more thorough review of the data on the foliar dissipation of carbaryl and prepare a more detailed response during the 60 day public comment period. 24 Persistence Microbially Mediated Processes Page: 21 Paragraph: 3 Line: 3 EPA comment: with an initial concentration of 11.2 mg/ L, degraded with a half life of 4.0 days in sandy Aventis' response: The units for ppm soil concentration should be given as mg/ kg.

Page: 21 Paragraph: 3 Line: 4 5 EPA comment: The major degradate was 1 naphthol which further degraded rapidly to non detectable levels within 14 days. Aventis' response: The data from this study demonstrate that under aerobic soil conditions the formation and decline of 1 naphthol, starting from parent carbaryl is complete in less than 14 days. The study data show an average maximum 1 naphthol level of 34.5% of applied carbaryl by day 1, declining to 2.8% by day 2, 0% by day 4, 0.2% by day 7 and 0% at day 14. These data suggest a preliminary half life of less than 1 day for the major degradate 1 naphthol.

Page: 21 Paragraph: 3 Line: 8 9 EPA comment: In anaerobic aquatic soil carbaryl with an about 10 mg/ L degraded with a half life of 72.2 days. Aventis' response: Several words appear to be missing from this sentence. One suggestion: "Carbaryl degraded with a half life of 72.2 days in anaerobic aquatic sediment with an initial carbaryl concentration of about 10 mg/ L."

Page: 22 Paragraph carried over from page 21 Line: 4 on pg 22 EPA comment: Chudhry and Wheeler, 1988 Aventis' response: This reference is not included in the reference list 25 Mobility Page: 22 Paragraph: 1 Line: 1 EPA comment: Carbaryl is considered to be mobile to very mobile in soils. Aventis' response: See response directly below.

Page: 22 Paragraph: 3 Line: 1 2 EPA comment: Based on batch equilibrium experiments (MRID 43259301) carbaryl was determined to be very mobile to mobile in soils. Aventis' response: The classification of carbaryl as mobile to very mobile is inconsistent with measured Koc values of 177 to 249. According to the widely used classification scheme of McCall, et al. (1980) wherein Koc values between 150 and 500 denote medium mobility in soil, carbaryl would be classified as having medium mobility in most soils. This classification of medium mobility is further supported by the acceptable column leaching study (MRID 43320701) in which aged carbaryl residues were only slightly mobile in a number of soils. The mobility of carbaryl would be expected to be higher in sandy soils or in soils of low organic matter.

Field Dissipation Page: 22 Paragraph: 5 Line: 3 EPA comment: The submitted field and aquatic dissipation studies were determined to be unacceptable, and did not provide useful information on movement and dissipation of carbaryl or its degradation products. Aventis' response: The field dissipation study (MRID 41982605) submitted in 1991 demonstrated that carbaryl dissipated very rapidly (t1/ 2 < 1 week) with no measurable leaching. The study included two sites, one in North Carolina and one in California. At the North Carolina site, ~ 95% of the Time 0 residues had dissipated by the first sampling period 7 days after application (the planned first sampling at 3 days was not collected due to rain). Similarly, ~ 85% of the Time 0 residues had dissipated by 7 days after application at the California site. Concerning the movement of carbaryl, samples were taken to a depth of 0.9 meters in increments of 0.15 meters. No residues were found below the upper 0.15 meters. 26 Page: 23 Paragraph: 3 Line: 2 EPA comment: Because of inappropriate sampling intervals, poor sample storage stability, lack of degradate monitoring, rainfall and irrigation that were less than evapotranspiration, and irrigation water with high pH, these studies do not provide reliable information on the rate of dissipation of parent carbaryl or formation of degradation products.

Aventis' response:   The estimated half life determined from this study was < 3 days. Sampling at intervals such that several sampling events are taken prior to the half life of the product is impractical for rapidly degrading chemicals (e. g., those with half lives less than a week). For this rapidly degrading chemical an estimate of the half life should be sufficient for risk assessments even if it is not precise.   After the report was submitted to California, the freezer storage stability recoveries at six and nine months were measured but not reported. Rainfall plus irrigation approximated an inch a week and was more than enough to maintain a good soil moisture for agricultural purposes.   Sulfuric acid is routinely added to irrigation water in the region of California where the field test was conducted to neutralize the water's high pH. Although not stated in the report, the irrigation water in the California trial was treated in the typical commercial fashion. The acid is injected into the irrigation pipe as water is pumped through it. Unfortunately, the pH of the water arriving at the field after treatment was not measured.

Aquatic Field Dissipation Page: 24 Paragraph: 2 Line: 3 EPA comment: They (do) not provide useable information on the dissipation of carbaryl and 1 naphthol in aquatic field conditions. Aventis' response:   The soil metabolism study referred to in the report found that the total water soluble metabolites did not exceed 5% of the total radioactive residue, the primary hydrolysis product, 1 naphthol, was not found, and that the only analyte of concern was the parent insecticide, carbaryl. A soil metabolism study reviewed concurrently by the Agency was issued later (MRID 42785101, classified "acceptable") with similar results. Although the major soil metabolite, 1 naphthol, was found at significant levels at day 0 and day 1, the levels were less than 0.7% by day 4 and non detectable by day 14. Two other metabolites were identified but never exceeded levels of 1.7% of the total residue. Again the only residue of concern was the parent insecticide, carbaryl.

  If present, 1 naphthol would have been detected by the residue method used to measure the residues of carbaryl in the soil. 27   The estimated half life determined from this study was < 2 days. Sampling at intervals such that several sampling events are taken prior to the half life of the product is impractical for rapidly degrading chemicals (e. g. those with half lives less than a week).

Page: 24 Paragraph: 2 Line: 4 EPA comment: Frozen storage stability data were provided for only 6 months, although the water samples were stored for up to 14 months and the soil samples were stored for up to 17.5 months prior to analysis. The data suggest that carbaryl and 1 naphthol degraded significantly during storage. In the six months of storage carbaryl degraded an average of 34 % in Texas water and 39% in from Mississippi. 1 naphthol degraded 50% in water from Texas and 69% from Mississippi. Degradation did not appear linear, and it is not possible to extrapolate out to 14 months. It was therefore not possible to evaluate the actual concentrations of carbaryl and 1 naphthol in the samples or estimate the dissipation rates. Aventis' response: The existing 6 month storage stability provides sufficient information to calculate the concentrations of carbaryl in the samples. However, the metabolite 1 naphthol was shown to degrade significantly under the same freezer conditions. This instability simply confirms that 1 naphthol's presence in the environment would be very limited and should not be of concern.

Foliar Dissipation Page: 24 Paragraph: Last EPA comment: The reported rates of carbaryl dissipation from foliar surfaces varies from 1 days to 30 days. In their review of literature data on pesticide foliar persistence, Willis and McDowell (1987) report that carbaryl dissipation rates varied from 1.2 to 29.5 days… For terrestrial risk assessment modeling EFED used 35 days… Aventis' response: As stated in comments to Table 3, the foliar dissipation half life used by EFED for terrestrial risk assessment is too long and should be corrected. Table IV of the Willis and McDowell review lists 10 foliar half lives for various formulations of carbaryl applied to different crops. Five of these half lives are for a study designed to evaluate a new analytical procedure for measuring carbaryl residues on plants. This study was conducted on plants grown in a greenhouse, with some of them receiving an unknown amount of simulated rainfall. These studies on greenhouse grown plants should not be used to evaluate foliar persistence in the field. The foliar persistence of pesticides can be considerably different for residues on and in plants grown in greenhouses versus the field. Eliminating the half lives for the greenhouse grown plants results in the following 28 half lives for carbaryl on field plants: Cotton, 1.2, 1.3, 1.5 days; strawberry, 4.1 days; tomato 1.4 days. Therefore, the longest half life of 4.1 days should be used for terrestrial risk assessment modeling.

Aventis will conduct a more thorough review of the data on the foliar dissipation of carbaryl and prepare a more detailed response during the 60 day public comment period.

Atmospheric Transport Page: 25 Paragraph: 1 Line: 2 EPA comment: Waite, et al., 1995 Aventis' response: This reference is not included in the reference list Page: 25 Paragraph: 1 Line: 3 EPA comment: Beyer et al., (1995) Aventis' response: This reference is not included in the reference list Page: 25 Paragraph: 3 Line: 5 EPA comment: Schomburg et al. (1991) Aventis' response: This reference is not included in the reference list 1 Naphthol Fate and Transport Page: 26 Paragraph: 2 Line: 1 2 EPA comment: In an aerobic soil metabolism study (MRID 42785101), 1 naphthol degraded rapidly to non detectable levels within 14 days. 29 Aventis' response: The data from this study demonstrate that under aerobic soil conditions the formation and decline of 1 naphthol, starting from parent carbaryl, is complete in less than 14 days. The study data show an average maximum 1 naphthol level of 34.5% of applied carbaryl by day 1, declining to 2.8% by day 2, 0% by day 4, 0.2% by day 7 and 0% at day 14. These data suggest a preliminary half life of less than 1 day for the major degradate 1 naphthol. This half life can be used for preliminary environmental fate modeling to estimate EECs for 1 naphthol.

Page: 26 Paragraph: 3 Line: 1 EPA comment: No guideline information was submitted on 1 naphthol sorption. Literature information suggests that it is not strongly sorbed. Aventis' response: The statement suggesting that 1 naphthol is not strongly sorbed to soil should be deleted. In support of the 1 naphthol sorption statement the Agency has cited only one paper by Karthikeyan et al. (1999) that was conducted using aluminum hydroxide as the sorbent. Soil is composed of much more than aluminum hydroxide, so this study is more of a mechanistic description of sorption to this one component of soil and not a study of sorption to soil as a whole. This cited study reported that 1 naphthol does not show significant sorption to aluminum hydroxide when allowed to sorb for 20 hours in the dark in the absence of oxygen. However, there was a significant increase in sorption with increasing equilibration time, and as the Agency stated, the increase is influenced by pH, as would be expected for an acidic phenolic compound.

Additional information available in the literature demonstrates that the sorption of 1 naphthol to soil is stronger than that seen for carbaryl itself. Hassett et al. (1981) have demonstrated that the sorption of 1 naphthol was the result of sorption to organic carbon resulting in an average Koc of 431 ± 40 for 10 of the 16 soil samples they tested. In the remaining 6 soil samples the Koc was even higher (1,645 to 15,618). Hassett et al. (reference submitted as part of 30 day response document) hypothesized that the higher Kocs in these 6 soils, in which the organic carbon to clay ratio was very low, the clay surfaces were more accessible and the sorption of 1 naphthol was apparently controlled by the clay fraction. In Burgos et al. (1999), cited by EPA elsewhere in the RED, it was shown that there is significant sorption of 1 naphthol to two sandy soils, and that oxidative coupling reactions were responsible for the strongly bound portion. In an earlier paper by Burgos et al. (1996) it was shown that both biologically mediated and soil catalyzed oxidative coupling lead to significant binding of 1 naphthol residues to soil. These data indicate that 1 naphthol is less mobile and less susceptible to leaching than carbaryl itself, and they demonstrate that at least a portion of the 1 naphthol residue is tightly sorbed to soil constituents.

To meet the requirement by the Agency for information on the adsorption and desorption of 1 naphthol, the registrant is conducting an adsorption/ desorption study to meet the 30 163 1 guideline. Study results should be available for submission to the Agency in the first quarter of the calendar year 2002.

Aquatic Exposure Assessment Surface Water Page: 26 Paragraph 4 Line 1 EPA comment: Five crop scenarios: apples, field corn, sweet corn, oranges and sweet potatoes scenarios were use in modeling for surface water EEC. Aventis' response: The fifth crop modeled was sugar beets (not sweet potatoes).

Page: 27 Table 4 EPA comment: Hydrolysis half life at pH 9 stated to be 5 hours. Aventis' response: The study results, and the summary of the study presented on page 20, show the correct half life at pH 9 to be 3.2 hours.

Page: 27 Table 4 EPA comment: (Koc = 211 for SCIGROW) Aventis' response: This is the mean Koc. According to EPA guidance the median Koc (209) should be used for SCI GROW, although this difference would not be expected to affect the model results.

Pages: 27 28 Table 5 EPA comment: Tier II surface water estimated environmental concentration (EEC) values derived from PRZM/ EXAMS modeling for use in ecorisk assessment (calculated using standard pond.) Aventis' response: The PRZM input tables were not provided for the standard pond scenarios, so the assumption is made that the same application methods were used for the standard pond as for the Index Reservoir scenarios that were provided as an electronic copy of a draft of Appendix B. 31 It would be of benefit for the Agency to state which of the carbaryl labels were used to develop the "maximum" label application rate scenarios. It would be useful to add another column to this table to specify which method of application was used to generate the EECs rather than the generic "air/ ground" in column 1. There are a number of errors in the input parameters (noted below) that would lead to changes in the calculated EECs and therefore the risk quotients for these uses.

If the modeling for the "average" scenarios were conducted using aerial applications for citrus and apples (as was the case for the Index Reservoir scenarios), then the model results over estimate the contributions from spray drift. Few applications to these crops are made aerially. Therefore, the model results over estimate the contributions from spray drift since the "average" applications to these crops are made using ground airblast equipment with a spray drift of 6.3% in the model versus aerial applications with a spray drift of 16%.

The "average" scenario for sweet corn in Ohio should be 3 applications at 1.1 lb. ai/ A/ application (as noted in the memo, "Average application rate from Quantitative Usage Analysis for Carbaryl, prepared July 21, 1998 by Frank Hernandez, OPP/ BEAD") and not the 2 applications at 3.4 lb. ai/ A/ application as listed in the table. It should be noted that the "average" scenario presented in this table, 2 applications per year at 3.4 lb. ai per application, exceed the maximum rate allowed on the label.

The maximum label rate application scenario for apples that is allowed by the Sevin brand XLR PLUS label (E. P. A. Reg. No 264 333), the Sevin brand 80WSP and CHIPCO Sevin brand 80WSP labels (E. P. A. Reg. No 264 526) and the CHIPCO Sevin brand SL label (E. P. A. Reg. No 264 335) is 5 applications at 3 lb. ai/ A/ application made every 14 days. The scenario used in the model applies less than the maximum amount of product allowed by the labels. In addition, if the same application timing was used in the modeling for the standard pond scenario as was used in the index reservoir scenario (applications made by air every 4 days) this would be a violation of the Aventis labels which restrict applications to a minimum of every 14 days.

The "average" scenario for sugar beets in Minnesota should be 1 application at 1.3 lb. ai/ A/ application (as noted in the memo, "Average application rate from Quantitative Usage Analysis for Carbaryl, prepared July 21, 1998 by Frank Hernandez, OPP/ BEAD") and not 1 application at 1.5 lb. ai/ A/ application as listed in the table.

The "Citrus" scenario would be more appropriately labeled Oranges. For the average scenario, the 3.4 lb. ai/ A/ application rate listed in Table 5 is for oranges (as noted in the memo, "Average application rate from Quantitative Usage Analysis for Carbaryl, prepared July 21, 1998 by Frank Hernandez, OPP/ BEAD"), which is the highest "average" application rate for any type of citrus. Therefore, this "average" scenario for oranges are at the high end for all citrus and overestimates the PRZM/ EXAMS derived EECs for use in the other citrus crops. "Average" application rates for other citrus as listed in the memo are: 32 Lemons – 1.3 applications at 2.7 lb ai/ A/ appl Grapefruit – 1.6 applications at 1.4 lb ai/ A/ appl Citrus, other – 1.8 applications at 1.8 lb ai/ A/ appl The maximum label application rate for citrus is 7.5 lb ai per application, not 5 lb ai, with a maximum of 20 lb ai total allowed per year. In California only, a single application is allowed at the rate of 5 to 16 lb ai per season for control of California red scale and yellow scale.

Estimated Environmental Concentrations for Terrestrial Ecological Risk Assessment Page: 29 Paragraph: 2 Line: 2 4 EPA comment: In the absence of reliable foliar dissipation data a dissipation half life of 35 days is used. Published literature shows that carbaryl dissipation rates vary, and are among the highest observed for any pesticide (Willis and McDowell, 1987). Aventis' response: As stated in more detail above, some of the foliar dissipation half lives listed in this reference are high because they were generated in the greenhouse, not in the field, and therefore they should not be used. Eliminating the half lives for the greenhouse grown plants results in the following half lives for carbaryl on field plants: Cotton, 1.2, 1.3, 1.5 days; strawberry, 4.1 days; tomato 1.4 days. Therefore, the longest half life of 4.1 days should be used for terrestrial risk assessment modeling.

Page: 29 Paragraph: 2 Line: 6 EPA comment: A more thorough description of the model calculations and ELL FATE outputs are attached in Appendix B. Aventis' response: No such description or attachments were provided, so Aventis did not have the opportunity to evaluate the model.

Page: 29 Paragraph: 2 Line: last EPA comment: …Tables 4,7, 8 and 9, Appendix D. Aventis' response: These tables are in Appendix C. 33 5.0 Drinking Water Assessment Water Resources Assessment Page: 29 Paragraph: 3 Line: 3 EPA comment: Carbaryl tends not to partition to soil, aquifer solids, or sediment. Aventis' response: This sentence is misleading and should be reworded. Carbaryl does partition onto these sorbents, but the sorption coefficients are not high. Suggest rewording this such as: "Carbaryl tends not to bind tightly to soil, aquifer solids, or sediment."

Page: 29 Paragraph: 4 EPA comment: Under certain conditions carbaryl can be expected to persist in the environment. Under low pH conditions the compound is stable to hydrolysis. In anaerobic environments metabolism is fairly slow (t½ = 72 days). This suggests that carbaryl may leach to ground water and persist in some aquifers. Aventis' response: This last statement should be removed. In contrast to this hypothesis are the data presented in the NAWQA and EPA databases that demonstrate that carbaryl is not likely to leach to ground water and is not likely to persist in aquifers. The fact that carbaryl has been widely used in agricultural and urban settings for more than 35 years, and yet is found at concentrations greater than 0.1 : g /L in only 0.027% of the agricultural wells, urban wells and aquifers sampled by NAWQA (Kolpin, 2001), indicates that this statement has little merit. Furthermore, the last sentence is in direct contradiction to the statement made at the beginning of the preceding paragraph that carbaryl "… has limited potential to leach to ground water."

Page: 30 Paragraph: 1 Lines 1 3 EPA comment: Surface water monitoring studies show that carbaryl is the second most widely detected insecticide after diazinon. Carbaryl, at typically low concentrations, is found in greater than 20 % of surface samples at concentrations up to 7 ppb. Aventis' response: These summary statements are based on the NAWQA database, with the exception of the 7 ppb concentration. The highest reported value in the NAWQA database is 5.5 ppb. The value of 7 ppb does not come from the NAWQA database but from the report by Werner et al. (2000). In fact, a maximum carbaryl concentration of 8.4 ppb was reported for surface water samples in the California DPR surface water database (see discussion section). The sources of the information should not be mixed, or the source of the information should be explicitly stated. 34 Drinking Water Exposure Assessment Page: 30 Paragraph: 2 Line: 3 4 EPA comment: Carbaryl is the second most commonly detected insecticide in surface water, and can be expected to contaminate drinking water derived from surface water bodies. Aventis' response: The surface water monitoring program conducted by Aventis shows an insignificant impact of carbaryl on drinking water.

Page: 30 Paragraph: 2 Line: 7 EPA comment: The maximum reported value was 7.0 : g /L. Aventis' response: The maximum value reported in the NAWQA database is 5.5 : g /L. The only carbaryl detection reported in the study by Werner et al. (2000) was 7.0 : g /L. The maximum value reported in the California DPR Surface Water database is 8.4 : g /L. Since all of the statistics made in this paragraph refer to the NAWQA data, the reference to the maximum reported concentration should be 5.5 : g /L.

Page: 30 Paragraph: 4 Line: 2 EPA comment: Older studies using GC or GC/ MS generally have poor recovery and quantitation limits. Because of this difficulty in analysis the actual concentration of carbaryl in groundwater and surface waters may be higher than reported. Aventis' response: The basis for making this generalization is not readily apparent and these statements should be removed. Comments regarding the recovery reported for the GC/ MS method used in the NAWQA survey are made below in reference to statements made on page 34 paragraph 5, and are elucidated in the discussion section at the end of this response document. The method detection limit (MDL) reported for the GC/ MS method used for the NAWQA program is 0.003 ppb (Zaugg et al., 1995; Larson et al. , 1999). The limit of detection for the HPLC/ MS/ MS method used in the carbaryl surface water monitoring study being conducted by the registrant (LOD, 0.002 ppb; LOQ 0.030 ppb) is similar to the GC/ MS method used for the NAWQA program. In addition to the GC/ MS method used in the NAWQA program, carbaryl was also analyzed by HPLC/ photodiode array detection in a limited number of samples with a MDL of 0.008 (Werner et al., 1996). Therefore, the quantification limits reported for the GC/ MS method used to generate a majority of the carbaryl data in the NAWQA database is very similar to the quantification limits for available HPLC methods. See the discussion section at the end 35 of this response document for a summary of the available NAWQA data obtained by the GC/ MS and HPLC/ PDA methods.

Page: 30 Paragraph: 4 Line: 4 EPA comment: More recent studies using HPLC/ MS should provide better data on the true extent and magnitude of water contamination from the use of carbaryl. Aventis' response: Aventis believes that our ongoing targeted surface water monitoring program using HPLC/ MS/ MS accurately reflects the extent and magnitude of carbaryl exposure in drinking water derived from surface water.

Drinking Water Modeling Page: 31 Paragraph: carried over from page 30 Line: 8 EPA comment: A partial list of input parameters for the PRZM/ EXAMS modeling are given in Table 4. Aventis' response: The partial list of input parameters in Table 4 includes multiple conservative assumptions likely to lead to significant over estimation of the potential surface water concentrations of carbaryl.

Page: 31 Paragraph: 2 Line: 1 EPA comment: For the Index Reservoir scenario using maximum label rates, acute EEC values ranged from about 10 : g/ L from sugar beets to about 500 : g/ L from citrus (Table 6). Aventis' response: Table 6 on page 33 shows a concentration of 19 : g/ L for sugar beets treated with the maximum label rate of 2 x 1.5 lb ai, not 10 as stated in this sentence. A low EEC value of 9 : g/ L for sugar beets results from the "maximum reported" application scenario of 1 x 1.2 lb ai/ A.

Page: 31 Paragraph: 2 Line: 3 EPA comment: Chronic EECs ranged from about 1 to 28 : g/ L. 36 Aventis' response: Table 6 on page 33 shows that this is correct when considering all of the model scenarios. However, either the same maximum label rate reference should be used as in the preceding sentence (in which case the minimum chronic EEC would be 2), or the basis for the preceding sentence should be changed from the maximum label rate to include all application scenarios to keep the comparisons consistent.

Page: 31 Paragraph: 2 Line: 6 EPA comment: It is highly unlikely that any but the most extensive targeted monitoring would capture the actual peak concentrations. Aventis' response: The role of a peak concentration in dietary exposure assessment is undergoing reexamination within EPA. The current policy of EPA appears to define a certain percentile as an appropriate value for use in screening assessments, but the exact percentile to be used is being currently set by EPA management. (The most recent documents from EPA cite the 95 th or 99 th percentile.) For more comprehensive assessments, a distribution of values is preferred.

Page: 31 Paragraph: 2 Line: 7 EPA comment: The results of the modeling provide a conservative, though not unreasonable, estimate on possible concentrations drinking water.( sic) Aventis' response: The modeling, performed according to EPA procedures, provides an upper bound estimate on potential concentrations in drinking water from surface water. Whether the modeling estimates are reasonable depends on the specific assumptions. For carbaryl, the three year monitoring program (conducted according to EPA and ILSI guidance available at the time the study was started) shows that the model calculations are unreasonable. These conservative assumptions include a 3x factor on both the aerobic soil and aerobic aquatic half lives, assuming the maximum drift rate for aerial applications throughout the county (in Florida citrus almost all applications are by air blast with ground equipment), and the application rate over a watershed. The conservative nature of the application assumption alone probably results in an overprediction by at least two orders of magnitude. The modeling calculations assume an application rate of 17.4 lbs/ acre of watershed annually. In Hardee County, the county with the highest usage of carbaryl, the average use rate on a countywide basis is only 0.31 lb/ acre (See Appendix II). In Manatee County, the county with the highest usage containing a watershed used to supply drinking water, the average rate on a countywide basis is 0.027 lb/ acre. 37 Page: 31 Paragraph: 2 Line: 8 EPA comment: A more detailed assessment of the source of water used to provide drinking water and the relationship between the areas where carbaryl is used and surface water sources is required to more accurately evaluate possible human exposures. Aventis' response: As mentioned by EPA in this document, ground water is the source of the majority of Florida drinking water. Many of the counties with the highest use of carbaryl contain no watersheds used to provide drinking water. As discussed more fully in Appendix I, the watershed supplying the Manatee County Water Treatment Plant appears to have the most carbaryl usage of drinking water watersheds in Florida.

Water Treatment Effects Page: 31 Paragraph: 3 Line: 8 EPA comment: Since relatively (sic) few water treatment facilities in the U. S. use ozone the limited data available do not indicate that carbaryl is likely to be degraded in the majority of treatment plants. Aventis' response: The monitoring program conducted by the registrant shows that removal occurs in some treatment plants. The effect of treatment seemed to be greater in systems using carbon treatment.

Page: 33 Table 6 EPA comment: Drinking Water EECs Aventis' response: Many of the comments for this table are similar to those for the EECs for ecological risk found in Table 5.

The PRZM model input parameters for the Index Reservoir scenarios were received as an electronic copy of a draft of Appendix B. These input files are very useful for assessing the scenarios that have been modeled.

It would be useful to add another column to Table 6 to specify which method of application was used to generate the EECs (and thus the application efficiency and spray drift values). It would be of benefit for the Agency to state which of the carbaryl labels were used to develop the "maximum" label application rate scenarios. There are a number of errors in the input parameters (noted below) that would lead to changes in the calculated EECs and therefore the risk quotients for these uses. 38 The model parameters listed in the electronic draft of Appendix B show that the "average" scenarios for citrus and apples were conducted using aerial applications. Few applications to these crops are made aerially. Therefore, the model results over estimate the contributions from spray drift since the "average" applications to these crops are made using ground airblast equipment with a spray drift of 6.3% versus aerial applications with a spray drift of 16%.

The "maximum label rate" application scenario for apples that is allowed by the Sevin brand XLR PLUS label (E. P. A. Reg. No 264 333), the Sevin brand 80WSP and CHIPCO Sevin brand 80WSP labels (E. P. A. Reg. No 264 526) and the CHIPCO Sevin brand SL label (E. P. A. Reg. No 264 335) is 5 applications at 3 lb ai/ A/ application made every 14 days. The scenario used in the model applies less than the maximum amount of product allowed by the labels. In addition, application timing was used in the modeling for the index reservoir scenario (applications made by air every 4 days) that would be a violation of the Aventis labels which restrict applications to a minimum of every 14 days.

The "average" scenario for sweet corn in Ohio should be 3 applications at 1.1 lb ai/ A/ application (as noted in the memo, "Average application rate from Quantitative Usage Analysis for Carbaryl, prepared July 21, 1998 by Frank Hernandez, OPP/ BEAD") and not the 2 applications at 3.4 lb ai/ A/ application as listed in the table. The PRZM input file shows the correct inputs of 3 applications at 1.1 lb ai/ A/ application.

The "average" scenario for sugar beets in Minnesota should be 1 application at 1.3 lb ai/ A/ application (as noted in the memo, "Average application rate from Quantitative Usage Analysis for Carbaryl, prepared July 21, 1998 by Frank Hernandez, OPP/ BEAD") and not 1 application at 1.5 lb ai/ A/ application as listed in the table and the PRZM input file.

The "Citrus" scenario would be more appropriately labeled Oranges. For the average scenario, the 3.4 lb ai/ A/ application rate listed in Table 5 is for oranges (as noted in the memo, "Average application rate from Quantitative Usage Analysis for Carbaryl, prepared July 21, 1998 by Frank Hernandez, OPP/ BEAD"), which is the highest "average" application rate for any type of citrus. Therefore, this "average" scenario for oranges is at the high end for all citrus and overestimates the EECs for use in the other citrus crops. "Average" application rates for other citrus as listed in the memo are: Lemons – 1.3 applications at 2.7 lb ai/ A/ appl Grapefruit – 1.6 applications at 1.4 lb ai/ A/ appl Citrus, other – 1.8 applications at 1.8 lb ai/ A/ appl Ground Water Resources Page: 34 Paragraph: carried over from page 33 Line: 3 EPA comment: U. S. EPA. Pesticides in Groundwater Database (Jacoby et al., 1992) 39 Aventis' response: This reference is not provided in the reference list.

Page: 34 Paragraph: 3 Line: 3 EPA comment: Detections were from (sic) mainly from three use sites: wheat (5.8 % of well samples from wheat land use), orchards and vineyards (1.7 % of well samples from orchard and vineyard land use), and urban (1.8% of urban groundwater samples). Aventis' response: Updated information (noted below) is not summarized in the same manner as in this statement, so direct comparisons cannot be made easily. However, the updated information indicates a similar pattern of low concentrations of carbaryl detections in a limited number of ground water resources.

Page: 34 Paragraph: 3 Line: 6 EPA comment: Limitations in analytical methodology (described elsewhere) apply to groundwater sample analysis also suggesting that there (sic) actual maximum concentrations and extent of contamination may be significantly higher. Aventis' response: This statement is misleading and should be deleted. The validation of the most widely used GC/ MS method for the data contained in NAWQA show recoveries of 86 to 94% at spiking levels of 0.1 to 1.0 : g/ L with an MDL of 0.003 : g/ L. The HPLC method validation reported recoveries of 58 to 64% % at spiking levels of 0.1 to 1.0 : g/ L with an MDL of 0.018 : g/ L. Furthermore, using the GC/ MS method, a mean recovery of 115% was found for field matrix spikes of carbaryl at spiking levels of 0.1 : g/ L. With the GC/ MS method MDL of 0.003 : g/ L and a mean recovery of 115% for the field matrix spikes, this method cannot reasonably be characterized as stated by EPA. Additional details of the method validations and field matrix spikes are provided in the `Discussion Section' at the end of this response.

Page: 34 Paragraph: 3 Line: last EPA comment: …and updated information is available at: http:// water. wr. usgs. gov/ pnsp/ ja/ est32/. Aventis' response: This web page was last updated in 1998. A more recent update by Kolpin was posted June 11, 2001 at: http:// water. wr. usgs. gov/ pnsp/ pestgw/ and is the source of the updated information included in the `Discussion Section' at the end of this response. 40 Surface Water Resources Monitoring Data Page: 34 Paragraph: 4 Line: 5 6 EPA comment: Because of limitation in the analytical methods used there is some question as to the accuracy of carbaryl analysis. Aventis' response: This generalized statement needs to be qualified or deleted. Whereas the authors of reports written as part of the NAWQA program have been clear about the potential limitations of the quantitative nature of the carbaryl data in the database, they have also been clear about the validity of the qualitative nature of the data. The use of the multiresidue method in the NAWQA program does have some limitations as a result of the large numbers of diverse pesticides and degradation products that they are monitoring. However, the QC/ QA data generated as part of the NAWQA program (described in the discussion section on surface water at the end of this response) demonstrate the validity of the detections of carbaryl in the studies. The monitoring study conducted by the registrant, and reported in this section, does not have the same potential limitations in the analytical method since the method is looking specifically for carbaryl. Therefore, the analytical method used by the registrant does not raise questions about the accuracy of the carbaryl analysis.

Page: 34 Paragraph: 4 Line: 5 6 EPA comment: Poor analytical methods probably have resulted in lower detection rates and lower concentrations than actually present. Aventis' response: This generalized statement should be deleted for reasons provided above and in the discussion section.

NAQWA (sic) 41 Change to NAWQA Page: 34  35 Paragraph: 5 Lines: 5 8 EPA comment: Carbaryl analytical results are fairly poor, with a typical mean percent recovery of 24% (   = 15) in laboratory quality control samples, and a method detection limit (MDL) of 0.003 ug/ L. This suggests that the values reported do not represent the maximum concentrations that exist, and that surface water contamination may be more widespread than the data show. Aventis' response: These statements are misleading and should be updated with further quality control data supplied by NAWQA.

A discussion of the analytical method used in the NAWQA program is presented in the USGS Open File Report 95 181 (see Zaugg et al. (1995) in references). The mean percent recovery of 24% noted above can be found in Table 9 of this report and is by no means "typical". A mean recovery value of 24% was reported for reagent grade water fortified at a level of 0.03 µ g/ L with a method detection limit said to be 0.003 µ g/ L. Additional recoveries for fortified water samples (reagent grade, ground and surface waters) ranged from 10 to 202% (see discussion section). The carbaryl data in the NAWQA database are amended with an "E" qualifier to indicate the variability found with this method, not because the carbaryl concentrations are underestimated.

Additional evaluations of field blank, field matrix spike and lab control spike samples as part of the NAWQA program can be found in a provisional report by Martin (1999). This report demonstrates the lack of detection of carbaryl in 100% of the field blanks, and median recoveries of 94.4% in 306 field matrix spikes and 93.0% in 1000 lab control spikes, each at spiking levels of 0.1 µ g/ L. These data suggest an adequate level of detection of carbaryl in the method used in the NAWQA survey of surface and ground water. See the additional discussion at the end of this document for further information regarding recoveries in spiked surface and ground water.

Page: 35 Paragraph: 2 Line: 7 EPA comment: …at about 0.1 percent of the amount used in the basins (Larson et al., 1999) http:// water. wr. usgs. gov/ pnsp/ rep/ wrir984222/ load. html. The estimated carbaryl use on in agricultural applications is about 4 million pounds suggesting that 400,000 pounds are delivered to the nations streams draining agricultural areas. 42 Aventis' response: This estimated use of carbaryl for agricultural applications over estimates the use of carbaryl by about 1 million pounds. BEAD and USGS data cited on pages 6 and 7 are consistent with lower total pounds of carbaryl applied. In addition, 0.1 percent of 4 million pounds would be 4,000 pounds, not 400,000 pounds. If the 1987 – 1996 average of 2.5 million pounds carbaryl is used in the calculation, the total load suggested to be delivered to streams draining agricultural areas would be 2,500 pounds.

Registrant Monitoring Study Page: 35 Paragraph: 4 Line: 11 EPA comment: Carbaryl was analyzed by HPLC/ MS with a limit of detection… Aventis' response: The analytical method used by the registrant in the surface water monitoring study uses tandem mass spectrometry (MS/ MS) as the detection method. This type of detection involves quantification of "daughter" ions from a selected mass fragment and is more selective than an MS method. Therefore, to accurately reflect these differences, the method should be labeled as HPLC/ MS/ MS.

Page: 36 Paragraph: 3 Line: 9 EPA comment: In several cases finished water had higher concentration than raw water, and finished water had detectable carbaryl when the raw did not. The highest concentration measured was in finished water (0.18 ppb). Raw water sampled at the same time had much lower concentration (0.010). 43 Aventis' response: This statement is misleading and certainly does not consider the analytical uncertainty for concentrations below the level of quantification and near the level of detection. There were only two cases when finished water was greater than raw water when the concentrations in finished water were greater than 0.01 ppb (only one third of the quantification limit). One case was when the raw water was 0.009 ppb and the finished water was 0.011 ppb. These two analyses are essentially equivalent, especially considering that they are only about a third of the quantification limit. The other case was at the Deerfield community water system. This drinking water facility uses a small river without a reservoir as a source for a small Community Water System. Farms are located immediately upstream of the facility. The intake is also not continuous (shut down over weekends). Therefore, getting a matching sample is quite difficult, especially for a short duration spike as a result of spray drift, summer thunderstorm, or perhaps a spill that almost immediately enters the river a runoff event. The rarity of this event is demonstrated by the absence of residues of this magnitude the next year (2000). Samples collected through this time of the year in 2001 also do not indicate a similar event. Although the data from this site cannot be used to determine the peak concentration, the data provide a distribution of residues through the three year period which will define up to the 99 th percentile concentration of the distribution.

The Deerfield, Michigan community water system is one of the systems in which the greatest variability of residues would be expected. Most of the other community water systems are located on larger rivers, lakes, or reservoirs.

Because the design of study called for analysis of finished water only when there were residues in the raw water, there was only one finished sample analyzed when the raw water contained no residues. This sample was collected at the Deerfield community water system at the sampling interval after the finding of 0.16 ppb in the Deerfield system. The residue level in this sample was 0.004 ppb. The difference between 0.004 ppb and non detect is insignificant, and if real can probably be attributed to water at much higher concentrations remaining in the system from the previous week.

Page: 36 Paragraph: 4 Line: 1 EPA comment: Non targeted monitoring, such as the NAWQA program, has shown much higher concentrations occur indicating that this study, while useful, can not be used to describe the overall distributions that occur throughout the entire use area. Aventis' response: The targets of the drinking water monitoring conducted by the registrant and the NAWQA program are different. The NAWQA program characterized surface water concentrations within a study area while the Aventis drinking water monitoring measured residues in inlets and outlets of drinking water facilities. Also the drinking water monitoring program considered only use areas with drinking water supplies. However, 44 for FQPA dietary assessments, the appropriate target is drinking water rather than surface water.

The main reason why the drinking water monitoring study did not show residues as high as in the NAWQA program is the location of the sampling points. Drinking water supplies tend to be located on larger surface water bodies than NAWQA sampling points (or in other words, the intakes for community water systems tend to be downstream of NAWQA sampling points). This additional time allows for additional degradation and dilution to occur. Finding the highest concentration at the Deerfield, Michigan system is not surprising since this intake is on one of the smallest surface water bodies included in the monitoring study (see response to Page: 36, Paragraph: 3, Line: 9 above for a more detailed explanation).

Page: 36 Paragraph: 4 Line: 4 EPA comment: This study does not provide sufficient information to allow estimation of actual peak and mean concentrations that actually occur in all use areas. Aventis' response: Because most of the samples did not contain carbaryl residues, accurate estimates of the actual peak and mean concentrations can not be obtained. However, the distributions obtained from all sites can be used to define up to the 99 th percentile concentration. The average cannot be accurately determined; however, the time weighted average is only slightly above the limit of detection (and certainly less than 0.01 ppb) at all 20 sites.

The peak concentration in this study was measured at a community water system on a small river. The registrant agrees that the sampling schedule was not adequate to determine the true peak in such systems. Most of the other community water systems are located on larger rivers, lakes, or reservoirs. Therefore, the peak values are not likely to be an order of magnitude greater than the amounts present in the collected samples.

The distributions obtained in this study are suitable for use in dietary exposure assessments. When EPA policy establishes what percentile concentration is an appropriate regulatory endpoint, then these percentiles can be determined for each of the community water systems monitoring. These percentiles can then be compared with DWLOC values in screening assessments.

Page: 37 Paragraph: 2 Line: 1 EPA comment: Only limited information was submitted on sampling site selection… Aventis' response: The summary in Appendix I of this response provides a description of the sites considered for the monitoring study and the rationale for the selection of the twenty sites. This information demonstrates that the community water systems selected for this study 45 are representative of the systems that are most likely to contain the highest concentrations of carbaryl residues.

Page: 37 Paragraph: 3 Line: 3 EPA comment: This should include an explanation of why this study did not observe concentrations as high as those found in other, non targeted studies, and how the results of this study can be related to concentrations that occur throughout the country. Aventis' response: The main reason why the drinking water monitoring study did not show residues as high as in the NAWQA program is the location of the sampling points. Drinking water supplies tend to be located on larger surface water bodies than NAWQA sampling points (or in other words, the intakes for community water systems tend to be downstream of NAWQA sampling points). This additional time allows for additional degradation and dilution to occur. Finding the highest concentration at the Deerfield, Michigan system is not surprising since this intake is on one of the smallest surface water bodies included in the monitoring study (see response to Page: 36, Paragraph: 3, Line: 9 above).

Since the drinking water study targeted drinking water systems in high use watersheds, the data from this study are representative of the drinking water systems most likely to contain carbaryl.

Sacramento San Joaquin River Delta Page: 37 Paragraph: 4 Line: 4  5 EPA comment: Carbaryl was found to be the sole causative agent at one of 20 sites… The toxicity seemed to persist for several days… Aventis' response: The statement should be revised. The reference cited (Werner et al., 2000) lists carbaryl as "the primary toxicant" (not as the "sole causative agent"), even though an unknown was also found at the same time. No information about the "unknown" is provided. Both conclusions of "sole causative" and of "primary toxicant" cannot be substantiated without further evidence about the nature and concentration of the unknown. Actually, for another site the authors concluded about the unknown found there "in 3 of 21 samples, toxicity observed could not be entirely explained by the identified primary toxicants." Additionally, it is at least questionable if the analytical method employed would detect all potential toxicants beside the insecticides it was set up for.

The toxicity seeming to persist is not explained or substantiated in the reference. The citation of such dubious results should be removed from the RED. 46 6.0 Hazard and Risk Assessment for Aquatic Organisms Hazard assessment for Aquatic organisms Estuarine/ Marine Fish Page: 39 Paragraph: 2 Line: 6 EPA comment: …carbaryl water concentration of 1.2 : g/ ml… Aventis' response: To be consistent with the rest of the document the units should be presented in ppm (" carbaryl water concentration of 1.2 ppm")

Aquatic Plants Page: 40 Paragraph: 2 Line: 6 EPA comment: Guideline 122 2 is not fulfilled. Aventis' response: The chapter should be revised. As detailed above (comments to Page 2 of the Memorandum), studies were submitted in 1992. The status for this requirement in an October 04, 2000 OPP Guideline Status Report (Chemical Review Management System) lists the guideline 122 2 status as "Acceptable/ Satisfied".

Risk Assessment for Aquatic Organisms Page: 40 Paragraph: 4 Line: 3 EPA comment: …corresponding levels of concern (LOCs) is presented in Appendix D. Aventis' response: The risk quotients are currently listed in Appendix C.

Estuarine/ Marine Fish Page: 42 Paragraph: 1 Line: 17/ 18 EPA comment: Chronic toxicity studies with an estuarine/ marine fish species is required. 47 Aventis' response: This requirement should be waived. Given the relatively short half life of carbaryl in the aquatic environment and the low acute risk, it is unlikely that estuarine/ marine fish species would be exposed to a chronic risk.

Page: 42 Paragraph: 2 Line: 1 EPA comment: There is one carbaryl use in particular that presents a major acute and chronic risk to estuarine/ marine fish. Aventis' response: This sentence should be rephrased. While there might be an acute risk from the application to oyster beds, given that there is only one application every six years according to the reference cited by EPA, it is improbable that estuarine/ marine fish would be exposed to a chronic risk.

7.0 Hazard and Risk Assessment for Terrestrial Organisms Hazard Assessment for Terrestrial Organisms Mammalian Page: 46 Paragraph: 4 Line: 1 EPA comment: With a rat LD50 of 307 mg/ kg… Aventis' response: Typographical error, the rat LD50 is 301 mg/ kg.

Risk Assessment for Terrestrial Organisms Avian Risk Nongranular Formulations Page: 47 Paragraph: 4 Line: 5 EPA comment: …levels of concern (LOCs) is presented in Appendix D. Aventis' response: The risk quotients are currently listed in Appendix C. 48 Page: 48 Paragraph: 1 Line: 3 EPA comment: … for 34 of 43 uses at maximum reported rates, and for 37 of 72 uses at "average" rates. (Appendix D, … Aventis' response: The risk quotients are currently listed in Appendix C.

Granular Formulations Page: 48 Paragraph: 2 Line: 5 EPA comment: …for any of the granular carbaryl uses (Appendix D, Table 6). Aventis' response: The risk quotients are currently listed in Appendix C.

Mammalian Risk Risk to Herbivores/ Insectivores: Nongranular Formulations Risk Quotients for Herbivores/ Insectivores Based on Less than Maximum Label Use Rates Page: 48 Paragraph: 3 Line: 3 & 4 EPA comment: … (Appendix D, Table 10a) and maximum reported (Doane data) use rates data available for 43 uses (Appendix D, Table 10b) Aventis' response: The risk quotients are currently listed in Appendix C.

Risk Quotients for Herbivores/ Insectivores Based on Maximum Label Use Rates Page: 48 Paragraph: 6 Line: 1 EPA comment: Carbaryl is moderately toxic to small mammals on an acute oral basis (rat LD50 = 307 mg/ kg) Aventis' response: Typographical error, the rat LD50 is 301 mg/ kg. By using the lower LD50 all acute mammalian risk quotients will change slightly. 49 Page: 49 Paragraph: 1 Line: 3 EPA comment: …corresponding levels of concern (LOCs) is presented in Appendix D. Aventis' response: The risk quotients are currently listed in Appendix C.

Risk to Granivores: Nongranular Uses Chronic risk: Nongranular Uses Page: 50 Paragraph: 2 Line: 8 EPA comment: …summarized in Appendix D, Table 9. Aventis' response: The risk quotients are currently listed in Appendix C.

Reproduction Effects Page: 50 & 51 Paragraph: 4 / 1 EPA comment: (Review of alleged reproduction effects of carbaryl). Aventis' response: The paragraphs should be changed. The literature cited in these paragraphs show ambivalent results. While some references seem to support the claim of reproductive effects, other references do not. The potential for reproductive effects in mammals was evaluated in the recently submitted 2 generation study in rats. No reproductive effects were seen in this guideline study. The NOAEC of 75 ppm was based on pup mortality.

Page: 51 Paragraph: 4 EPA comment: Feeding 2 or 20 mg/ kg of carbaryl to pregnant rhesus monkeys (Macacca mulatta) Aventis' response: This paragraph should be deleted. As there are no native monkey species in the U. S., this reference is irrelevant for U. S. wildlife species. Additionally, the reference cited is only a brief abstract article consisting of one 17 line paragraph. Such information should not be the basis for use in a RED risk assessment. 50 9.0 References (non MRID)

Some of the references cited in EPA's list are not full scientific articles, but only abstracts from meetings (e. g. DeNorsica, 1973; Doughtery et al. , 1971, Chapin et al. 1997). Such "publications" should not be used as references considered in risk assessments. Without a sufficient description of methods and a presentation of detailed results these studies cannot be evaluated to determine if the findings are or are not scientifically plausible. Similarly, at least three of the references (Gladenko et al. 1970, Krylova et al. 1975, Smirnov et al. 1971) cited as proof for reproductive toxicity are in Russian in Cyrillic writing making an appropriate and timely evaluation difficult. Due to the limited review time during the 30 day comment period, the registrant could not peruse all references. A more detailed response will be provided during the 60 day comment period.

Page: 59 EPA comment: Carmel, R. F., Imhoff, J. C., Hummel, P. R., Cheplick, J. M. and Donigan, A. S., 1997. Aventis' response: The first name should be Carsel.

Page: 59 EPA comment: Nkedi Kizza and Brown (1988) Aventis' response: The date should be 1998.

Appendix A: Environmental Fate Study Reviews (DERs)

Page: 62 ff EPA comment: (Environmental fate DERs are included) Aventis' response: The DERs should not be included in the RED. Publication of DERs together with the RED is unusual and will put Aventis in a competitive disadvantage.

Appendix B: Refined Water Memo EPA comment: MEMO TO BE INSERTED WHEN APPROVED 51 Aventis' response: This memo was provided as an electronic copy and needs to be inserted into the document. It included text that repeated several sections of the EFED document and it included PRZM input tables for the drinking water concentrations using the Index Reservoir scenario. It would have been of benefit to have the same PRZM inputs for the "standard pond" scenarios that were used to estimate surface water concentrations used in the aquatic risk assessments.

Appendix C: Ecological Risk Assessment Toxicity Endpoints Used in the Risk Assessment Page: 129 (e version)

EPA comment: Aventis' response:

Mammalian acute oral LD50 rat = 307 mg/ kg The correct LD50 is 301 mg/ kg Mammalian chronic (reproduction) NOAEC rat = 80 ppm The result of the recently submitted 2 generation rat study should be used (75 ppm)

Avian Acute and Chronic Risk Page: 130 (e version) Paragraph: 1 Line: 1 EPA comment: Since the avian LC50 is greater than 5,000 ppm (Appendix E), Aventis' response: The toxicity data are currently listed in Appendix D.

Page: 132 – 135 (e version) EPA comment: (Acute Risk Quotients in Tables 4 and 5, as well as throughout the document were a reference is made to these quotients) Aventis' response: As the acute risk quotients are calculated on the basis of an LC50 of > 5000 ppm, the quotients should be given as "< (value)", not just the value. The values should also be changed accordingly throughout the document where a reference is made to these quotients. 52 Risk from Exposure to Non granular Products Page: 137 – 147 (e version) EPA comment: (Text and tables 7  10) Aventis' response: Text and tables should be revised. A rat LD50 of 307 mg/ kg was used to calculate the acute risk quotients. The correct value is 301 mg/ kg. For calculation of the chronic risk quotient a NOAEC of 80 ppm was taken from a developmental study. The NOAEC of 75 ppm from a more relevant 2 generation rat study recently submitted should be used instead.