1 OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

MEMORANDUM

DATE : June 20 , 2011

SUBJECT: EFED Registration Review Preliminary Problem Formulation for Permethrin ( PC Code 109701; Case No. 2510; DP Barcode D384703 )

FROM: José L. Meléndez, Chemist Amanda Solliday, Biologist Keith Sappington, Senior Advisor Environmental Risk Branch V Environmental Fate and Effects Division (7507P)

THROUGH : Mah T. Shamim , Ph.D. , Branch Chief Environmental Risk Branch V
E nvironmental Fate and Effects Division (7507P)

TO: Kaitlin Keller , Chemical Review Manager Kathryn Jacob , Team Leader Michael Goodis, Branch Chief Risk Management and Implementation Branch III Pesticide Re

- evaluation Division (7508P)

The Environmental Fate and Effects Division (EFED) has completed the preliminary problem formulation for the ecological risk, environmental fate, endangered species, and drinking water assessment to be conducte d as part of the Registration Review of the pyrethroid insecticide permethrin (attached)

. Functioning as the first stage of the risk assessment process for registration review, this problem formulation provides an overview of what is currently known about the environmental fate and ecological effects associated with permethrin use. It also describes the preliminary ecological risk hypothesis and analysis plan for evaluating and characterizing risk to non

- target species in support of the registration of perm ethrin

.

Use and Usage The Agency has limited use and usage information relevant to urban exposures and residential uses of pyrethroids, including permethrin . The Agency intends to use available non

- agricultural2 use and usage data, such as the Kline datab ase, the California Department of Pesticide Regulation’s (CDPR) Pesticide Use Reporting Data and Pest Control Operator’s usage survey, and the Residential Joint Venture Task Force homeowner survey data (2003), to inform reasonable assumptions regarding var ious applications and information related to urban/residential use and potential environmental exposure

. Additional information on non

agricultural use and usage of pyrethroid products, specifically permethrin , would be useful in order to reduce those unc ertainties for the final environmenta l risk assessment for permethrin

.

Environmental Fate Many of the environmental fate properties of permethrin are known. Nonetheless, there is uncertainty with respect to some of the laboratory fate studies because the y were performed at concentrations that exceeded the solubility limit of the chemical , or in the presence of high concentrations of a cosolvent. Permethrin is moderately persistent in aerobic environments, but

appear s to be more persistent in anaerobic en vironments. The fate of permethrin in publicly

owned treatment works is also an uncertainty.

Based on a bioconcentration factor of 570

- 610x in whole fish, permethrin is moderately bioaccumulative and depuration occurs at moderate rates.

Ecological Effects In addition, there are ecological data gaps that need to be addressed to reduce uncertainties in the preliminary risk picture for permethrin

. Permethrin is very highly toxic to fish, aquatic invertebrates and terrestrial invertebrates . Howe ver, some uncertainty exists concerning the potential for acute and chronic adverse aquatic effects to l isted and non

- listed aquatic species.

Specifically, data are needed for quantifying permethrin toxicity to benthic aquatic invertebrates via chronic sedime nt exposure, chronic effects to estuarine/marine invertebrates via water column expos ures and acute effects to oyster shell deposition . An additional acute water column toxicity test with the freshwater amphipod Hyalella azteca is also requested based on t he increased sensitivity of this species to pyrethroid insecticides. Acute fish and aquatic invertebrate water column studies are also needed to accurately qu antify the effects of permethrin used in combination with the synergists p iperonyl butoxide and MG K

- 26

. Based on information available in the open literature, there is some indication that potential exists for temperature

mediated changes in pyrethroid toxicity and this will be examined in the upcoming risk assessment for permethrin.

E valuation of the chemical structure of permethrin degradates ( e.g. m

- PBA, m

- PBAlc, and cis

and trans

- DCVA) suggests little similarity to the active parent compound, and the cleavage of the ester linkage during degradation of the parent structure is expected to result in a significantly decreased toxicity of those degradates relative to the parent. Limited aquatic toxicity data that is available to the Agency confirms this assumption.

A number permethrin amphibian toxicity tests were identified in the open literature for the previous ecological assessment for permethrin. None of these studies provide d estimates of toxicity that were ultimately used quantita tively in this r isk assessment. H owever , they do3 provide some information regarding the hazard of permethrin to amphibians and will be used for characterization in the upcoming risk assessment

.
Although toxicity to avian species is low based on previously submitted studi es with upland game bird and waterfowl species, u ncertainty exists concerning the potential for acute adverse effects to listed and non

- listed passerine birds

. Permethrin is moderately toxic to mammalian species on an acute basis. Mammals can exhibit chron ic reproductive effects as a result of higher levels of permethrin exposure.

No data has been submitted to accurately quantify the potential adverse effects of permethrin to terrestrial and aquatic plants.

E FED does not currently conduct risk assessments on non

- t arget insects, but information from standard laboratory tests and permethrin incident reports suggest the potential for risk to honey bees and other beneficial insects. In consideration of the available information concerning the

non

- sy stemic nature of permethrin foliar residues and risk mitigation options, the nature of residues reported in pollen, wax and bees, and further development of pollinator risk assessment methods and guidelines, the Agency is not requesting additional data on permethrin exposure and effects on pollinators as part of this preliminary Problem Formulation. Instead, the Agency is placing the need for additional data “In Reserve” pending the outcome of the aforementioned scientific activities, comments from stakehol ders on the need for additional data and the review of additional information concerning this topic.

# Environmental Fate and Ecological Risk Assessment Preliminary Problem Formulation in Support of Registration Review of Permethrin

DP Barcode D384703 PC Code 109701

Case No. 2510



### June 20, 2011



# Environmental Fate and Effects Division Office of Pesticide Programs U.S. Environmental Protection Agency

Prepared by: Amanda Solliday, Biologist José L. Meléndez, Chemist

Secondary Review: Keith Sappington, Senior Advisor Mah T. Shamim, Ph.D., Chief

Environmental Risk Branch V2 Table of Contents

1. Purpose ....................................................................................................................... . 3 2. Problem Formulation .................................................................................................. 4 2.1. Nature of Regulatory Action .................................................................................... 4 2.2. Previous Risk Assessments and Scientific Advisory Panels ................................... 4 3. Stressor Source and Distribution ................................................................................ 9 3.1. Mechanism of Action ............................................................................................. 13 3.2. Overview of Pesticide Usage ................................................................................. 14 3.3. Environmental Fate and Transport ......................................................................... 29 4. Receptors................................................................................................................... 37 4.1. Aquatic and Terrestrial Effects .............................................................................. 37 4.2. Incident Database Review ...................................................................................... 50 4.3. Ecosystems Potentially at Risk .............................................................................. 53
5. Assessment Endpoints .............................................................................................. 53 6. Conceptual Model .................................................................................................. 5 4 6.1. Risk Hypothesis ................................................................................................... 54 6.2. Conceptual Diagram ............................................................................................ 55 7. Analysis Plan ....................................................................................................... .. 62 7.1. Stressors of Concern .............................................................................................. 63 7.2. Measures of Exposure ............................................................................................ 63 7.3. Measures of Effect ................................................................................................. 66 7.4. Integration of Exposure and Effects ...................................................................... 67 7.5. Deterministic and Probabili stic Assessment Methods ........................................... 67 7.6. Endangered Species Assessments .......................................................................... 68 7.7. Drinking Water Assessment .................................................................................. 68 7.8. Endocrine Disruptor Screening Program ............................................................... 68 7.9. Preliminary Identifica tion of Data Gaps ................................................................ 69 7.9.1. Environmental Fate ......................................................................................... 69 7.9.2 Ecological Effects ............................................................................................ 75 8. References ................................................................................................................ .... 84 9. Fate and Ecotoxicity Bibliography ............................................................................. 88 Appendix A. Data Request Justification Tables ............................................................ 117 Appendix B. Summaries of the Reported Perm ethrin Ecological Incidents in the EIIS Database ...................................................................................................................... .... 1213 1. Purpose

The purpose of this problem formulation is to provide the foundation for the ecological risk assessment that will be conducted for the regist ered uses of permethrin during Registration Review. As such, it articulates the purpose and ob jectives of the risk a ssessment, evaluates the nature of the problem, and provides a plan for analyzing the data and characterizing the risk (USEPA, 1998). Additionally, th is problem formulation is in tended to identify data gaps, uncertainties and potential assumptions needed to address those uncertainties in characterizing the ecological risk associated with the registered uses of permethrin.

Permethrin is a Type I synthetic pyrethroid curren tly registered for numer ous diverse uses that span a large variety of use sites and geographi cal regions. Type I pyr ethroids do not have a cyano group substitution in the alpha position of the alcohol moiety of the ester structure; in contrast, Type II pyrethroids have the cyano group. Permethrin is a broad spectrum insecticide that targets adults and larvae of many diverse species of biting, chewing, scaling, soil, and flying invertebrates. Permethrin is a neurotoxic ins ecticide with contact and stomach action, having a slight repellent effect. The primary biological effects of permethrin on insects and vertebrates reflect an inhibition of the correct firing of ne urotransmitter deliver signals from one cell to another via nerve membrane inhi bition of the voltage gated Ca 2+ channels coupled with a stimulatory effect on the voltage gated Na + channels.

Formulation types registered for permethrin incl ude wettable powders, wate r dispersible granules (dry flowable), emulsifiable concentrates liqui d, pressurized gas, pressu rized liquid, liquid readyto-use products, granulars, seed treatments and dusts. Application methods include: direct spray, aerial spray, ground spray, hand sp ray, airblast, mist/fogging, soil br oadcast, surface spray, soil incorporation, soil inject ion, granular (aerial or ground), chem igation. Application equipments include among others, mist sprayer, fogger, airc raft, truck-mounted spraye r, sprinkler irrigation, airblast and duster. In add ition, spray methods may use ultra-low volume (ULV) nozzles which suspend the product in the air for a longer duration, in order to intercept flying insects. Potential permethrin uses include agricu ltural (in/on food/feed crops); nur sery uses; home garden uses; ornamental uses; forestry uses; turf uses; indoo r/outdoor industrial, comme rcial, and residential uses; fire ant control; control of ectoparasites on domestic animals; and public health uses ( i.e. for mosquito abatement) in urban and rural set tings. Permethrin may also be used to treat clothing, which is used to prevent mosquito bite s. For agriculture uses, maximum seasonal rates usually range from 0.1 to 0.4 lb a.i./A and, depending on the crop, the maximum number of permethrin applications per s eason usually range from 1 to 8. Permethrin may be applied yearround. Non-agricultural use exceeds that of us e on agricultural crops. According to BEAD’s Chemical Profile dated 05/11/2011 (Brassard et al. 2011) for permethrin:

“Approximately 400,000 pounds of permethrin activ e ingredient (a.i.) is applied to 3 million acres of agricultural crops annua lly. Approximately 2.5 million pounds of permethrin a.i. is applied annually by consumers, pest control operators, nursery/greenhouse operators, and mosquito ab atement personnel... Permethrin also has non-Federal Insecticide, Fungicide, Rodentic ide Act (FIFRA) pharmaceutical uses as a pediculicide for the treatment of head lice and scabies. The Food and Drug4 Administration (FDA) approved use of the pe sticide-containing pharmaceutical products under the Federal Food, Drug, and Cosmetic Act (FFDCA).”

2. Problem Formulation

2.1. Nature of Regulatory Action

This report summarizes the Environmental Fa te and Effects Division’s (EFED) Problem Formulation for the Registration Review of permethrin. The Agency has completed previous risk for the use of this chemical, which serve as the basis for this assessment.

The Food Quality Protection Act (FQPA) of 1996 mandated the EPA to implement a new

program, i.e ., registration review ( http://www.epa.gov/oppsrrd1/ registration_review/ ). All pesticides distributed or sold in the United States generally must be registered by the EPA. The decision to register a pesticide is based on the co nsideration of scientific data and other factors showing that it will not cause unreasonable risks to human health, workers, or the environment when used as directed on product labeling. The re gistration review program is intended to ensure that, as the ability to assess risk evolves and as policies and practices change, all registered pesticides continue to meet th e statutory standard of no unreas onable adverse effects to human health and the environment. Changes in scien ce, public policy, and pest icide use practices will occur over time. Through the new registration review program, the Agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely.

As part of the implementation of the new Regist ration Review program purs uant to Section 3(g) of the Federal Insecticide, Fungi cide and Rodenticide Act (FIFRA), the Agency is beginning its evaluation to determine whether permethrin continues to meet the FIFRA standard for registration. This problem formulation for the en vironmental fate and ecological risk assessment chapter in support of the regist ration review is intended for th e initial docket opening the public phase of the review process.

2.2. Previous Risk Assessments and Scientific Advisory Panels

Recent Agency ecological risk assessments conducte d on permethrin indicated risk concerns for freshwater and estuarine/marine organisms, in cluding benthic organsims. It was noted that a number of studies demonstrated that applications of permethrin technical and formulations of permethrin are likely to adversely impact nontar get beneficial insects. Toxicity data are not available for terrestrial, aquatic non-vascular a nd aquatic vascular plan ts and the potential for risk to these taxa remains an uncertainty.

Most recently, in 2010 the Agency conducted an ecological assessment to evaluate potential direct and indirect effects of permethrin use on the Valley Elderberry Longhorn Beetle ( Desmocerus californicus dimorphus ) (VELB) to evaluate concerns with the chemical identified in the suit Center for Biological Dive rsity (CBD) vs. EPA et al ., (Case No. 07-2794-JCS). Due to5 the broad use pattern of permethrin across the st ate of California, including both agricultural and non-agricultural uses, the potential exists for perm ethrin use in any given area to spatially and temporally coincide with the VELB. The Ag ency made a Likely to Adversely Affect determination from the use of permethrin base d on direct effects to the VELB. There were exceedances of the Agency’s interim level of concern (LOC of 0.05) for listed terrestrial invertebrates for all of the modeled spray applic ation scenarios assesse d, with risk quotients (RQs) ranging from 0.16 to 7400, and the high probabi lity of an individual mortality occurrence based on the highest acute RQ for te rrestrial invertebrates (~1 in 1). Indirect effects to terrestrial prey items and habitat modificati on were also identified. The Agency determined that there is the potential for modification of de signated critical habitat from labeled use of permethrin in California based on the potential for direct effects to the VELB , adverse effects on terrestrial invertebrate pollinators of the elderberry (host plant of the VELB) and reported incidents of phytotoxicity following permethrin use (USEPA 2010) 1

.
In October 2008, the Agency conducted a listed sp ecies risk assessment to assess the potential risks of permethrin to the federa lly-listed California red-legged frog (Rana aurora draytonii ) (CRLF), California clapper rail ( Rallus longirostris obsoletus ) (CCR), Salt marsh harvest mouse ( Reithrodontomys raviventris ) (SMHM), San Francisco garter snake ( Thamnophis sirtalis
tetrataenia ) (SFGS), and Bay checkerspot butterfly ( Euphydryas editha bayensis ) (BCB) (USEPA 2008a) 2 . In addition, the 2008 assessment eval uated whether thes e actions can be expected to result in modificat ion of designated critical habita t for the CRLF and BCB. The 2008 risk assessment examined 48 agricultural and non-agricultural permethrin use scenarios, including alfalfa, nut trees, avocados, cole crops, corn, forestry, fruit trees, garlic, leafy vegetables, cucurbit vegetables, nursery uses, onions, potato and tu rnip, row crops, tomatoes, turf, ant mound treatments (residential, agricultural, turf, r ecreational areas), mosquito control, barrier treatment (fence rows, hedge rows, range land, ur ban and rural structures), residential turf and ornamentals, outdoor perimeter treatments , termite treatment, residential garden uses, and down-the-drain applications ( e.g. , pet shampoos). Based on the best available information, the Agency made a May Affect and Likely to Adversely Affect (LAA) determination for the CRLF, CCR, SFGS, SMHM, and BCB from the use of permethrin based on RQs that exceeded levels-of-concern for freshwater fish, aquatic- phase amphibians, freshw ater invertebrates, estuarine/marine fish and estuarine/marine i nvertebrates. Potential acute risk beyond Agency levels-of-concern was identified for all aquatic ta xa in all modeled scenarios, with the exception of risk to estuarine/marine fish from exposure to permethrin soil barrier treatment for fencerows and hedgerows. Additionally, the Agency determined that there was the potential for modification of CRLF designated cr itical habitat from the use of the chemical, but that there was not the potential for modification of BCB designated critical habitat.

The national-level EFED chapter of the Reregist ration Eligibility Decision Document (RED) for permethrin (Dated April 5 th 2006; DP Barcode D326784, USEPA 2006b) and the subsequent

1 Available at http://www.epa.gov/oppfead1/endanger/lit status/effects/redl eg-frog/index.html (accessed 01/27/11).

2 Available at http://www.epa.gov/oppfead1/endanger/lit status/effects/redl eg-frog/index.html (accessed 01/27/11).6 Addendum to the Revised EFED RED Chapter for Permethrin (Dated April 5 th 2006; DP Barcode D328142, USEPA 2006c) found that permethr in exposure in aquatic media (water column and sediment/ porewater), can potentially o ccur at levels that exceed the Agency’s levels of concern (LOCs). Risks were identified for li sted and non-listed aqua tic organisms (fish and water-column and sediment-dwelling invertebrate s) with acute and chronic LOC exceedances. For terrestrial organisms, the potential for chronic risk to mammalian species was also identified, with dose-based chronic RQs exceeding the LOC for all but one of the scenarios tested. Although risk was not quantified for terrestrial invertebrates, risk could not be precluded and it was noted that a number of studies demonstrated that applications of formulations of permethrin are likely to reduce the numbers and possibly eliminate populations of beneficial insects. Acute risk to mammalian species and acute and chronic ri sk to avian species app eared to be low, and no exceedances of the Agency’s LOCs were identified. Finally, toxicity data were not available for terrestrial or aquatic plant species and the potential for risk remains an uncertainty. However, additional data were not requested in the 2006 RE D because “information from other pyrethroids suggest no direct toxic concern to plants fr om exposure to this family of compounds.”

In addition to the assessment associating risks with mosquito abatement uses and agricultural uses, the same EFED chapter of the Reregistrati on Eligibility Decision document also raised the concern that the greatest volume of permethrin is used on non-agricultural sites. There was concern with the potential for permethrin runoff fr om residential areas and the applications such as perimeter treatments in and around buildings and lawn care use that co uld potentially result in residues being transported to adjacent aquatic areas . It was indicated that residues of permethrin and other synthetic pyrethroids at levels that are toxic to aqua tic organisms have been found in aquatic areas that receive runo ff from suburban developments.

1999 Scientific Advisory Panel A FIFRA Scientific Advisory Panel (SAP) in 1999 examined the sediment toxicity and fate of synthetic pyrethroids. In response to a question regarding whether sediment toxicity data on one pyrethroid (cypermethrin) could be used to predict sediment toxic ity to all pyrethroids, the panel generally supported the method of using data from a few pyrethroi ds to extrapolate information on toxicity to other pyrethroids. The panel recommended testing cypermethrin, bifenthrin (relatively non-toxic to freshwater aquatic organisms, very insoluble in water, large bioconcentration factor) and possibly tefluthrin (h ighly toxic to freshwat er aquatic organisms, stable in water, intermediate solubility in wa ter to cypermethrin and bifenthrin) (USEPA 1999). Although this agreement was made in 1999, the new Code of Federal Regulations (40 CFR) Part 158 ecological effects conditional data requirements that include sediment toxicity tests which are considered particularly impor tant for assessing ecological ri sks of synthetic pyrethroids, including permethrin.

In 2003, in response to the comments from the SAP on pyrethroids, EFED requested the following studies on cyfluthrin, cypermethrin, esfenvalerate and bife nthrin (Rexrode & Meléndez, memorandum dated 12/22/03):

EPA Guideline (GLN) 850.1735: Acute Sediment (freshwater) - Test organism: Hyalella azteca and Chironomus dilutus

. - Duration: 10 days, en dpoint is survival.7 EPA/600/R01/020: Chronic Estuarin e/Marine Sediment Testing - 28 day test on Leptocheirus plumulosus

. - Percentage of neonates that survive as adults. - Growth rate. - Reproduction (#eggs/ female, etc .). - Behavior.

A chronic 65-day freshwater test was also requested only for cypermethrin.

EPA/600/R-991064: Chronic Freshwater Sediment Testing - 65 day test on Chironomus dilutus

. - Survival. - Growth rate. - Reproduction (# eggs/ female, time to ovipos ition, proportion of females ovipositing, percent hatch).

The SAP commented on the use of K d or K OC to estimate concentrations of synthetic pyrethroids in sediments, recommending that the Agency reconsider K OC as a measure of the binding potential of synthetic pyrethroids to sediment and soil because the use of K d alone limits extrapolation to experime ntal conditions while K OC “allows one to estimate partitioning across a wide variety of soil/sediment types” (USEPA 1999) . The Panel expressed concern that standard methods used to measure sorption may not be applicable to highly hydrophobic compounds due to high solids to water ratio, cons ideration of the char acter of the organic matter, presence of dissolved organic carbon, use of non-represen tative soils and sedime nts as sorbents, and improper methods used to measure organic carbon.

While the biota-sediment accumulation factor is a widely accepted method of assessment of bioaccumulation in sediments, the Panel indi cated that the bioconcentration data for Daphnia

magna and Hyalella azteca should be sufficient to predict bioconcentration of pyrethroids. Finally, the Panel indicated that use of a so lid phase microextraction (SPME) method to determine the dissolved concentration in wate r could be used to a ccount for sorption of pyrethroids to organic ca rbon and colloids present in the water column in the measurement of bioconcentration factors.

2009 Scientific Advisory Panel For human healt risk assessment, OPP presen ted a “Proposed Common Mechanism Grouping for the Pyrethrins and Synthetic Pyrethroids to a FIFRA SAP in June 2009. OPP proposed two subgroups based on Type I or Type II effects rela ted to sodium current tails and neurobehavioral impact, with esfenvalerate and fenpropathrin showing symptoms of both types. The panel indicated that substances with mixed characte ristics could be include d in both groups (see p. 18 of SAP minutes, USEPA 2009). Permethrin is a Type I synthetic pyrethroi d. This mechanism of action assessment was performe d by HED/OPP and presented to the SAP to determine if a cumulative assessment is required for the synthetic pyrethroids. Information on the SAP is available in the docket (with non-co pyright material available at http://www.regulations.gov ) under EPA-HQ-OPP-2008-0489.8 EFED does not currently conduct cumulative ecologi cal risk assessments for several reasons. Specifically, the Division does not currently ha ve the methodology to conduct similar cumulative risk assessments for all of the (non-human) biological entities for which EFED has responsibility. In addition to a ddressing the toxicological aspect s of the cumulative effects of multiple pyrethroids to multiple biological entities, a cumulative ecological risk assessment would likely require consideration of exposure at a watershed scale in order to inco rporate spatial and temporal variability in pyrethroid applications into cumulative exposure assessment. EFED does not have the modeling tools developed for c onducting this type of assessment. However, the upcoming ecological risk assessment will consider open literature, currently available models and other lines-of-evidence ( e.g. , monitoring data), as availabl e, to address the potential for cumulative effects of pyrethroids in the risk de scription of the ecological risk assessment for permethrin.

Aquatic Toxicity Benchmarks For permethrin, the Office of Pesticide Progr ams has published aquatic life benchmarks for freshwater species, based on the most sensitive species from the most recent risk assessments (at http://www.epa.gov/oppefed1/ecorisk_ders/a quatic_life_benchmark.htm#benchmarks ). The aquatic life benchmarks for pe rmethrin are as follows:

Table 2.1. OPP Aquatic Life Benchmarks (F reshwater) for Permethrin in μg/L
Fish Invertebrates Non-vascular plants 1

Acute Chronic Acute Chronic Acute
0.395 0.0515 0.01 0.0014 68

1 There were no available acute benchmarks for vascular plants.

The Clean Water Act requires the Agency to publish water quality criteria that accurately reflect the latest scientific knowledge on the type and ex tent of all identifiabl e effects on health and welfare which might be expected from the presen ce of pollutants in any b ody of water, including ground water. While these recommended crit eria do not, in themselves, impose any requirements, states and authorized tribes can us e them to develop water quality standards. No US EPA Aquatic Life Ambient Water Qualit y Criteria document has been published for permethrin (at http://www.epa.gov/wate rscience/criteria/ ).

Impaired Water Bodies Permethrin is not individually identified as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Water Act, based on information provided at http://iaspub.epa.gov/tmdl_waters10/attains_na tion_cy.cause_detail_303d ?p_cause_group_id=885

. However, the pyrethroids as a group have been identified as a cause for impairment for three water bodies in Central Valley, California: De l Puerto Creek, Ingram Creek Site (from confluence with Hospital Creek to Highway 33 crossing) and second Ingram Creek Site (from confluence with San Joaquin River to confluence with Hospital Creek). At the present time, additional bodies of water are bei ng evaluated to be included into the list of impaired bodies of9 water; however, they have not been finalized (see http://www.waterboards.ca.gov/water_issu es/programs/tmdl/integrated2010.shtml and http://www.swrcb.ca.gov/rwqc b5/water_issues/tmdl/impaire d_waters_list/303d_list.shtml ). The 2010 proposed 303(d) list for California contains around 10 additional streams due to pyrethroids in the sediments. EFED will include relevant information on 303(d) listings in the final ecological risk assessment.

No Total Maximum Daily Load (TMDL) criter ia have been developed specifically for permethrin, based on information provided at http://iaspub.epa.gov/tmdl_waters10/attains_ nation.tmdl_pollutant_de tail?p_pollutant_group_id =885&p_pollutant_group_name=PESTICIDES . More information on impaired water bodies and TMDLs can be found at http://www.epa.gov/owow/tmdl/ . The Agency invites submission of water quality data for these pesticides. To the exte nt possible, data should conform to the quality standards in Appendix A of the OPP Standard Operating Procedur e: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s Regist ration Review Risk Assessment and Management Process (at http://www.epa.gov/oppsrrd1/regist ration_review/water_quality_sop.htm ), in order to ensure they can be used quantitatively or qual itatively in pesticide risk assessments.

National Water Quality Assessment (NAWQA) Permethrin is among the constituents monitore d by the National Water Quality Assessment (NAWQA), maintained by the U.S. Geological Survey. Sampling parameters include cispermethrin and/ or trans-permethrin in water and/ or bed sediments in units of μ g/L or μ g/kg. EFED will consult the NAWQA database for information on permethrin in water and sediments as part of its forthcoming ecological risk assessment.

3. Stressor Source and Distribution

Permethrin ( Table 3.1a ) is a synthetic pyrethroid insecticide. Its structure has three rings, two phenyl rings attached to each other by an oxyge n atom (phenyl and phenoxy), and a cyclopropyl ring. It is a Type I synthetic pyrethroid (meaning that it is not cyano substituted in the alpha position). The chemistry of permethrin may be dictated by its ester moiety. It would be expected to hydrolyze as the pH increases. This is confirmed from the hydrolysis study, where permethrin was stable at pH 3 and 6 and hydrol yzed slowly at pH 9. The structure of the molecule has two chiral centers which ra ise the number of possible isomers to 2 2 = 4. Permethrin consists of a mixture of thes e isomers (see below). Permethrin has a 2,2- dichloroethenyl group in the cyclopropane ring. Table 3.1a provides some identification information for permethrin, and its structure.

According to the International Programme on Ch emical Safety (IPCS INCHEM), Environmental Health Criteria 94, Permethrin, of the World Health Organization (1990): 3 “Technical products are a mixture of four stereoisomers with the configurations [1R, trans ], [1R, cis ], [1S, trans ], and

3 Available at http://www.inchem.org/documents/ehc/ehc/ehc94.htm accessed 01/07/11.10 [1S, cis ] in the approximate ratio of 3:2:3:2. The ratio of cis : trans is around 2:3 and the ratio of 1R:1S is 1:1 (racemic). The [1R, cis ] isomer is the most insecticidally active of the isomers, followed by the [1R, trans ] isomer.”

Table 3.1a. Identification information for permethrin

PARAMETER VALUE(s) units (chemical name) SOURCES

CAS Chemical Name (3-phenoxyphenyl)methyl 3-(2,2-dichloroethenyl)-2,2- dimethylcyclopropanecarboxylate Chemical’s data sheet a

PC Code 109701 OPP Databases

Case Number 2510 OPP Databases

IUPAC Chemical Name 3-phenoxybenzyl (1 RS ,3 RS ;1 RS ,3 SR )-3-(2,2- dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate

or 3-phenoxybenzyl (1 RS )- cis-trans -3-(2,2-dichlorovinyl)- 2,2- dimethylcyclopropanecarboxylate Chemical’s data sheet a

CAS Reg. No. 52645-53-1 Chemical’s data sheet a

Chemical Structure (unspecified stereochemistry, chiral centers are marked with asterisks) Chemical’s data sheet a

Molecular Formula C 21 H 20 Cl 2 O 3 Chemical’s data sheet a Molecular Weight 391.30 EXTOXNET (see below)

a. The chemical’s data sheet is available at http://www.alanwood.net/pesticides/permethrin.html , accessed 01/21/11

In the environment, permethrin is slow to hydrolyze and biodegrade. Pyrethroids such as permethrin, that have the 2,2-di chloroethenyl group attached to the cyclopropane moiety, are more stable to sunlight than earlier pyrethroids li ke allethrin or resmethrin . Permethrin has a low water solubility (0.0055 mg/L, Laskowski, 2002), and its hydrophobic nature leads to strong soil adsorption and a tendency to partition to sediment in aquatic systems (K FOC ≥ 28,200 L/kg, Hardly Mobile to Immobile, according to FAO Mobility Cl assification, FAO 2000). The reported value of log octanol/ wate r partition coefficient of 6.1 (K OW = 1.3 x 10 6 ) suggests that permethrin has the potential to bioaccumulate in aquatic organisms, assuming that chemical metabolism is negligible. However, the measured bioconcentration factor in fish (570-610 L/kg wet wt for whole fish, Table 3.5 ) is much lower than that expected based on K OW alone, which suggests that permethrin metabolism by fish is substantial. Permethrin has a high molecular weight of 391.30 g/mol and a vapor pressure of 1.48 x 10 -8 mm Hg. Due to its very low solubility, the calculated Henry’s Law Constant is moderately low (1.4 x 10 -6 atm-m 3 /mol). Permethrin’s air/water partition coefficient (K AW ) is 5.7 x 10 -5 , which classifies it as ‘slightly volatile from a water surface’ (USEPA 2008b), and the C water+soil /C air = 4.4 x 10 6 , which classifies the chemical as ‘non-volatile from moist soil’ (USEPA 2008b). Based on these properties, permethrin would have a slight potential to volatili ze from wet surfaces, but not from moist soil. The slight potential to volatilize of permethrin is attenuated by its tendency to bind to organic matter ( e.g. , soils, sediments, or organic matter and particulate in natural water). Table 3.1b lists various important physicochemical ch aracteristics of the chemical. Table 3.5 lists the other environmental fate properties of permethrin, along with information on the major and minor11 degradates detected in the submitted environmental fate and transport studies.

Table 3.1b. Physicochemical Properties of Permethrin

Property Permethrin
Value 1 MRID or Source

Density/ Specific Gravity 1.19 – 1.27 g/cm 3 Tomlin, C.D.S. (ed.). The Pesticide Manual – 11 th ed., British Crop Protection Council, Surrey, England 1997, p. 944 4

Melting Point ( 0 C) 34-35; cis-isomers, 63-65; trans-isomers, 44-47 Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997, p. 944 4

Boiling Point ( 0 C) 200 at 0.1 mmHg; >290 at 760 mmHg Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994., p. 784 4

Solubility in Organic Solvents In xylene and hexane >1000, methanol 258 (all in g/kg at 25 0 C) Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium, 11 th ed., British Crop Protection Council, Surrey, England 1997, p. 944 4

Vapor Pressure (mmHg) 1.48x10 -8 (Average of two values) (at 25 o C) MRID No. 42109801 & Laskowski
2002 5

2.18x10 -8 (at 25 o C) USDA, Agric. Res. Service 1995 4

1.9x10 -8 ( cis ), and 1.1x10 -8 ( trans ) Wells et al ., 1986

Henry’s Law Constant (atm-m 3 /mole at 20-25 o C) 1.4x10 -6 Calculated using solubility of 0.0055 mg/L and VP of 1.5x10 -8 mmHg

1.6x10 -7 Calculated using solubility of 0.0055 mg/L and VP of 2.18x10 -8 mmHg Water Solubility (mg/L) 0.0055 at 20°C Wollerton, 1987 5 0.175 (Average of 0.22, and 0.13) MRID No. 42109801 Octanol – water partition coefficient (log K OW ) 6.1 at 20 o C Wollerton, 1987 5

Dissociation Constant (pK
a and/or pK b ) Not available PPDB 6

Air-water partition

coefficient (K AW ) K AW = C air /C water = HLC/RT = 5.7 x 10 -5 ‘Slightly volatile from a water surface’ Calculated Value, USEPA, 2008b

Octanol-air partition

coefficient (K OA ) Constant Law s Henry' RT K

K K K OW

AW OW OA  

= 2.2 x 10 10 Calculated Value

C water /C air      

    

 6 air water 10 GMW P 760 R T S

C C = RT/HLC

= 1/K AW = 17,534 (unitless) ‘Slightly volatile from a water surface’ Calculated USEPA, 2008b

UV/visible light absorption Peaks at approximately 200 and 275 nm, with some tailing (in acetonitrile).

λ
max at 207 and 273 nm at pH 7. MRID 40242801 RD D274107 7

Volatilisation Flux Not available Not available

C water+soil /C air C water+soil /C air = (1/K AW ) (1/r + K d ) = 4.4 x 10 6
‘Non-volatile from moist soil’ Calculated Value USEPA, 2008b
OH Radical Reaction Half-life 0.467 days (at 12-hr days; 1.5 x 10 6 OH/cm 3 ) EPIWEB v.4.0 Estimate12 Table 3.1b. Physicochemical Properties of Permethrin

Property Permethrin
Value 1 MRID or Source
Ozone Reaction Half-life 49.3 days EPIWEB v.4.0 Estimate

Biomagnification Potential Presumption: If log K OA > 5, log K OW > 2 and the rate of chemi cal transformation is

low, the chemical may biomagnify in terrestrial food chains **
For permethrin, log K OA > 5, log K OW > 2

and therefore is identified as having a potential to biomagnify in terrestrial food chains. However, its rate of biotransformation is moderate in the environment, and it appears to be moderate in fish. Specifically, bioconcentration factors for permethrin are 570-610x, which are much lower than would be expected if biotransformation was minimal. Further, it is depurated relatively rapidly in fish

(depuration half -life ~4.7 days). Additionally, the potential of permethrin to

biomagnify in terrestrial food chains will

be reduced substantially should it be similarly biotransform ed by terrestrial organisms ** Gobas et al. 2003 and Armitage & Gobas, 2007 support this presumption, utilized here only as a broad reference to determine the potential for biomagnification.

1 When more than one value fo r a property was available, the bolded one is the one that was deemed the best, based on professional judgment (see also Laskowski, 2002, for further details).

2 http://www.alanwood.net/pesticides/permethrin.html (Accessed 01/07/11)

3 http://extoxnet.orst.edu/pips/permethr.htm (Accessed 08/20/10)

4 Information taken from the Hazardous Substances Data Bank (HSDB) at http://toxnet.nlm.nih.gov/cgibin/sis/htmlgen?HSDB (accessed 01/07/11)

5 As cited in Laskowski, 2002.

6 http://sitem.herts.ac.uk/aeru/iupac/Reports/515.htm (accessed 08/25/10)

7 As cited by HED in its RED document D357566, 4/1/09 (USEPA 2009a).

Various degradates were observe d in the laboratory studies ( e.g. m -PBA, m -PBAlc, and cis - and

trans -DCVA). These studies indicate that all of the identified degradates were the result of the rupture of the ester bond of the parent molecule. It has been believed that the resulting molecules are not as toxic as the parent because they presumably have lost the neurotoxic mode of action. Table 3.1c shows the chemical structures of pe rmethrin’s major degradation products. At this time, the degradates wi ll not be considered stressors of concern in the forthcoming environmental fate and ecological risk assessment (see Section 4 Receptors for information on degradate toxicity).

Table 3-1c: Permethrin Major Breakdown Products

Common

Name Chemical Name/ CAS # Structure13 Table 3-1c: Permethrin Major Breakdown Products

Common

Name Chemical Name/ CAS # Structure

m -PBA m -phenoxybenzoic acid

CAS # 3739-38-6

m -PB-alc or

m -PBalcohol m -phenoxybenzyl alcohol

CAS # 13826-35-2

cis -DCVA cis -permethric acid or
cis -3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropanecarboxylic acid

CAS # 59042-49-8

trans

DCVA trans -permethric acid or

trans -3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropanecarboxylic acid

CAS # 59042-50-1

3.1. Mechanism of Action

Permethrin is a neurotoxic ins ecticide with contact and stomach action, having a slight repellent effect. The primary biological effects of perm ethrin on insects and ve rtebrates reflect an inhibition of the correct firing of neurotransmitte r deliver signals from one cell to another via nerve membrane inhibition of the voltage gated Ca 2+ channels (calcium i on channels), coupled with a stimulatory effect on the voltage gated Na + channels (sodium ion channels).

The pyrethroids (including permethrin) share sim ilar modes of action and are considered axonic poisons. It is now well established that se vere neurological sympto ms of poisoning with pyrethroids in mammals and insects are the result of modification of Na + channel activity (cellular pores through which sodium ions are pe rmitted to enter the axon to cause excitation)14 (Matsamura, 1985). Advanced electrophysiological experiments using voltage clamp and patch clamp, together with ligand binding and ionic flux experiments, have unveiled unique actions of pyrethroids of keeping the Na + channel in the open state for an extremely long period, sometimes as long as several seconds. This modification of Na + channel properties lead s to hyperactivity of the nervous system. Pyrethroids have also been shown to suppress GABA ( gammaaminobutyric acid) and glutamate receptor-ch annel complexes and voltage-activated Ca 2+

channels.

Pyrethroids, including permethrin, stimulate repe titive action in the nervous system by binding to voltage-gated Na + channels, prolonging the Na + ion permeability during the excitatory phase of the action potential. This action leads to spontaneous depolarizations, augmented neurotransmitter secretion rate and neuromuscular block, which ulti mately results in paralysis of the insect.

Relative to physiological responses , researchers have designated tw o types of pyrethroids, Type I ( e.g. , S-bioallethrin, resmethrin a nd permethrin) and Type II ( e.g. , cypermethrin, deltamethrin and fenvalerate). Structurally, Type I pyrethroids lack the cyano group that characterizes Type II pyrethroids. Physiologically, T ype I pyrethroids have shorte r periods of sodium channel disruption (shorter inacti vation time) than that of Type II pyrethroids.

3.2. Overview of Pesticide Usage

The Label Use Information System (LUIS) report & Usage/Label Use Reports for permethrin were based on a subset of the universe of labels available for the chemical. Section 3 labels or major producers’ labels, along with all State and Local Needs (SLNs) labels, are included in the LUIS report. The purpose of these data is to represent the major uses of this chemical. This method to extract the labels is intended to pr ovide information about the maximum use rates and the use patterns for permethrin. The use information presented in this problem formulation was obtained from BEAD’s LUIS report, from the Pe rmethrin Chemical Profile for Registration Review dated 05/11/2011 (Brassard et al. 2011) (also supplied by BEAD), from various evaluated labels, and from the 2009 Revised Re registration Eligibility Decision Document. Permethrin has numerous uses. A summary of agri cultural use patterns for permethrin is shown in Tables 3.2 and 3.3 . Note that Table 3.2 provides information for agricultural as well as some of the non-agricultural uses, such as forestry uses, lawns and turf (i ncluding gulf courses), ornamentals, mosquito control, and others. There are other outdoor non-agricultural uses described further in Table 3.5

.

Table 3.2. Summary of use information for agricultural and various other outdoor nonagricultural uses of permethrin, based on a subset of representative labels.

Use Max. Single App. Rate (lb. a.i./A) # Apps.
at Max

Rate Seasonal App. Rate (lbs. a.i./A) Interval Between Apps. (days) App. Method (for abbreviations see the

footnotes to table)
Alfalfa 0.2/cutting 5 1.0 30 G, A, C, S
Almonds 0.25 3 0.75 10 G, A, C, S
Anise 0.2 5 1.0 7 G, A, C Apples 0.25 2 0.5 10 G, C, S, AB15 Table 3.2. Summary of use information for agricultural and various other outdoor nonagricultural uses of permethrin, based on a subset of representative labels.

Use Max. Single App. Rate (lb. a.i./A) # Apps.
at Max

Rate Seasonal App. Rate (lbs. a.i./A) Interval
Between Apps. (days) App. Method (for abbreviations see the

footnotes to table)
Artichokes 0.3 3 0.9 10 G, A, C, AB Asparagus 0.1 4 0.4 7 G, C, S, AB
Avocados 0.2 4 0.8 7 G, C, S Beans (not further characterized) Expressed in lb/gal 8 NS NS Foliar

Broccoli 0.2 4 0.8 5 G, A, C, S, AB Chinese Broccoli (not in CA) 0.2 4 0.8 5 G, A, C, S. AB Brussels Sprouts 0.1 4 0.4 5 G, A, C, S, AB Cabbage 0.2 2 0.4 (0.8 in HI) 5 G, A, C, S, AB

Chinese Cabbage 0.2 5 1.0 0 G, A, S, C
Cauliflower 0.1 4 0.4 (0.6 in HI) 5 G, A, S, C

Celery 0.2 5 1.0 (1.2 in HI) 7 G, A, C, S, AB

Cherries 0.2 3 0.6 10 G, A, C, S, AB Corn, Field 0.15 3 0.45 7 G, A, S, C, AB, ULV Corn, Sweet 0.2 4 0.8 3 G, A, C, S, AB, ULV Corn, Pop 0.15 or 0.2 3 or NS 0.45 or NS 7 or 6 G, A, C, S, AB, ULV Eggplant 0.15 4 0.6 (1.0 in HI) 7 G, A, C, AB, ULV

Filbert (Hazelnut) 0.25 3 0.75 10 G, A, C, S, AB
Garlic 0.2 4 0.8 10 G, A, C, AB, ULV
Horseradish 0.15 3 0.45 10 G, C, AB Leafy Vegetables 0.2 NS 1.0 5-7 G, A, C, S Leafy Vegetables 0.3 NS NS 5 Foliar

Lettuce 0.2 4 0.8 (1.2 in HI) 7 G, C, A, AB, ULV

Spinach , New Zealand Spinach 0.2 3 0.6 3 G, A, C, S, AB, ULV Amaranth (Chinese), Celtuce, Chard (Swiss), Chervil, Chicory, Chrysanthemum, Corn Salad, Cress (Garden & Upland), Dandelion, Dock (Sorrel), Endive (Escarole), Orach (Mountain Spinach), Cardoon, Parsley, Garden Purslane, Winter Purslane, Radicchio, Roquette (Arugula) 0.2 10 2.0 3-7 G, A, C, S, AB, ULV

Swiss Chard, Garden & Upland Cress, Dandelion, Dock (Sorrel), Endive (Escarole), Parsley, Garden Purslane, Winter Purslane 0.3 NS NS 5 Foliar

Collards 0.15 3 0.45 3 G, A, C, S, AB Turnip Greens, Turnip Root 0.15 3 0.45 3 G, A, C, S, AB
Kohlrabi 0.1 8 0.8 5 G, A, C, S
Okra 0.3 NS NS 5 Foliar16 Table 3.2. Summary of use information for agricultural and various other outdoor nonagricultural uses of permethrin, based on a subset of representative labels.

Use Max. Single App. Rate (lb. a.i./A) # Apps.
at Max

Rate Seasonal App. Rate (lbs. a.i./A) Interval
Between Apps. (days) App. Method (for abbreviations see the

footnotes to table) Chinese Okra (Hechma) 0.2 6 1.2 7 G, A, C, ULV
Onion 0.3 4 1.0 7 G, A, S, C, AB
Fennel 0.2 10 2.0 7 G, A, C, S, AB Papaya 0.15 5 0.75 10 G, A, C, AB

Peaches 0.25 3 0.75 10 G, A, S, C, AB, ULV
Nectarines 0.25 3 0.75 10 G, A, C, AB, ULV

Pears 0.25 (0.4 dormant only) 1 @ 0.4

+ 1 @ 0.25 0.65 10 G, A, C, AB, ULV

Peppers 0.2 4 0.8 5 G, A, C, S, AB

Pecans Expressed in lb/gal 5 NS NS G

Pistachios 0.3 3 0.9 10 G, A, S, C, AB

Potatoes 0.2 4 0.8 10 G, A, S, C, AB Soybeans 0.2 2 0.4 10 G, A, C, S, ULV Raspberries (red and black), Blueberries, Strawberries 0.3 8 NS NS Foliar

Tomatoes , Tomatillo 0.2 3 0.6 (0.8 in HI) 7 G, A, S, C, AB, ULV

Vegetable Cucurbits 0.2 NS 1.6 NS G, A, C, S Vegetable Cucurbits 0.33 8 NS NS Foliar Cantaloupe Melons 0.2 4 0.8 (1.2 in HI) 7 G, A, C, S, AB, ULV

Cucumbers 0.2 6 1.2 7 G, A, C, ULV Pumpkins 0.2 6 1.2 7 G, A, S, C, AB, ULV Summer Squash, Winter Squash (Hubbard) 0.2 6 1.2 7 G, A, C, S, AB

Watermelon 0.2 6 1.2 7 G, A, C, S, AB Chayote, C. Mixta/C.Pepo and Cucuzzi (Spaguetti Squash), Gherkin, Chinese Gourd (Wax), Gourds, Luffa, Melon, Bitter Melon (Balsam Pear), Citron Melon, Honeydew Melon, Mango Melon, Musk Melon, Winter Melon (Casaba/ Crenshaw/ Honeydew/ Persian), Momordica Spp., Squash, Butternut Squash, Zuccini Squash 0.2 6-8 1.2-1.6 7 G, A, C, S, AB

Gherkin, Chinese Gourd (Wax), Gourds, Melon, Bitter Melon, Citron Melon, Honeydew Melon, Mango Melon, Musk Melon, Winter Melon, Squash 0.3 NS, 8 NS NS Foliar

English/ Black Walnuts 0.25 3 0.75 10 G, A, C, AB, ULV
Rhubarb 0.2 5 2.0 5-7 G, A, S, C, ULV
Rhubarb 0.3 NS NS 5 Foliar17 Table 3.2. Summary of use information for agricultural and various other outdoor nonagricultural uses of permethrin, based on a subset of representative labels.

Use Max. Single App. Rate (lb. a.i./A) # Apps.
at Max

Rate Seasonal App. Rate (lbs. a.i./A) Interval
Between Apps. (days) App. Method (for abbreviations see the

footnotes to table)
Watercress 0.125 2 1.25 NS G, C Multiple agricultural crops, mosquito control, including mushroom 4 0.007 25 0.18 1 G, A (ULV)

Other Non-Agricultural Uses
Public Health 0.007 25 0.18 0.5 G, A (ULV) Forestry Cottonwood Hybrid (Poplar) 0.2 NS NS 0 A

Forestry (Softwoods, Conifers) 0.2 NS NS 5 G, A, S, C, AB, ULV Forestry (Softwoods, Conifers) 1.3 NS NS NS G, A, C, AB Christmas Tree Plantations 0.2 NS NS 5 G, S, C Conifers, Pine (seed orchard) 1.6 NS-6 NS NS-28 G, C Nursery Stock 0.2 NS NS NS G Roses (field grown) 0.2 NS NS NS G, A, C, AB, ULV
Turf in Recreational/ Commercial/ Industrial Areas, Ornamental Lawns & Turf, Residential Lawns 0.89 1.0 2-3 2.0 NS-10 G, A, C, S, AB, ULV Hose-End Sprayer

Golf Course Turf 0.1 NS NS NS G Golf Course Turf, Recreational Areas, Urban Areas 0.8 NS NS NS Directed Spray, Brush-on (Paintbrush) Barrier Treatment in Residential, Industrial, Recreational Areas, Urban Areas, Rights-of-Way, Wide Area/ General, Zoos 0.1 NS 0.18 NS G

Ornamentals Shade Trees, Herbaceous Plants 0.5 NS NS 4-7 G

Ornamental Non-Flowering Plants, Woody Shrubs and Vines 0.2 NS NS 0 G

Buildings/ Structures, Recreational Areas, Residential, Residential Lawns Perimeter Treatment 20.4 NS NS NS G

Ant Mound Treatment in Agricultural and Several Other Areas Up to 0.084 lb/ mound NS NS-0.04 NS, 7, 10 Drench

Rangelands 0.1 NS NS NS G, A, C, AB (in NM) Rights-of-Way/ Fencerows/ Hedgrows 0.1; 0.017 lb/ linear ft NS; NS 0.18: NS NS; NS Barrier Treatment; Soil Treatment

Paths/ Patios and Paved Areas Up to 341 NS NS NS G
Wood Protection Forest Units in lb/gal NS NS NS Pressure Treatment

4 Mushroom is not identified as a crop for which typical agricultural applications are performed; however, it is identified as a crop for which adulticide applications are allowed

.18 Table 3.2. Summary of use information for agricultural and various other outdoor nonagricultural uses of permethrin, based on a subset of representative labels.

Use Max. Single App. Rate (lb. a.i./A) # Apps.
at Max

Rate Seasonal App. Rate (lbs. a.i./A) Interval
Between Apps. (days) App. Method (for abbreviations see the

footnotes to table) Wood Protection Forest Products, Buildings (Outdoor) Up to 181 NS NS NS Soil or Void or Perimeter or Pressure

Treatment, Spray,Brush-on, Crack-andCrevice, Foam Application, Subslab Injection
Zoos 1.0 NS NS 14 Surface Treatment G = Ground, A = Aerial, C = Chemigation, S = Soil Incorporated, AB = Airblast, NA = Not Available; NS = Not Specified, ULV = Ultra Low Volume, Bolded crops/ uses are those that were mitigated in the process of reregistration of permethrin (USEPA 2009b).

Agricultural Use For agricultural products, appli cation methods include aerial or ground spray (foliar) and ULV. In addition, soil applic ations and seed treatments are possible.

Environmental Hazard Statements Permethrin is classified as a restricted use pe sticide due to its toxicity to fish and aquatic invertebrates. The following Environmental Hazards statemen ts are required (USEPA 2009b):

“This pesticide is extremely toxic to aquatic or ganisms, including fish and invertebrates. Do not apply directly to water, or to areas where surface water is presen t or to intertidal areas below the mean water mark. Do not apply when weather conditions favor drift from treated areas. Drift and runoff from treated areas may be hazardous to aquatic organisms in neighboring areas. Do not cont aminate water when disposing of equipment wash waters.”

“Under some conditions, it may also have a potential for transport into surface water in runoff (primarily adsorbed to suspended soil pa rticles), for several months or more after application. These include poorly draining or wet soils with readily visible slopes toward adjacent surface waters, frequently flooded area s, and areas overlying extremely shallow groundwater, areas with in-field canals or ditc hes that drain to surf ace water, areas not separated from adjacent surface wa ters with vegetated filter strips, and areas over-lying tile drainage systems that drain to surface waters.”

“This pesticide is highly toxi c to bees exposed to direct treatment on blooming crops or weeds. Do not apply this pr oduct or allow it to drift to blooming crops or weeds while bees are actively visiting the treatment area.”

Under spray drift precautions, th e labels for permethrin require a buffer zone of 10 ft around certain bodies of water, such as lakes, reservoi rs, rivers, permanent streams, marshes or natural ponds, estuaries and commercial fish farm ponds . The agricultural products should not be19 applied by ground equipment within a distance of 25 ft, or by aerial equipment within a distance of 150 ft, or by ULV within a distance of 450 ft fr om freshwater or estuarine/ marine bodies of water as described above. Furthe rmore, restrictions on the droplet size are required in the labels as follows:

“Use only medium or coarser spray nozzles (for ground and non-ULV aerial application) according to ASAE (S572) definition for standa rd nozzles. In conditions of low humidity and high temperatures, applicators should use a coarser droplet size.”

In addition to the liquid formula tion applications described in Table 3.2 , there are dust applications for multiple crops as described in Table 3.3 . It is noted that for dust applications, the application rate was not provi ded in the labels or could not be readily calculated; however, the maximum number of applications and the minimu m interval between applications is stated in many instances. Oftentimes, the number of appli cations for a given application on a crop for a dust formulation is greater than for th e same crop using a liquid formulation.

Table 3.3. Summary of use information for dust a pplications of permethrin, based on a subset of representative labels. Information presented is abridged from the LUIS – EFED Label Data Report 5

Use Single App.
Rate (lb. a.i./A) Number of Apps. Seasonal App. Rate (lbs. a.i./A) Interval
Between Apps. (days) App. Method Apples NS NS NS NS Dust Asparagus NS 4 NS NS Dust
Broccoli NS 8 NS NS Dust Brussel Sprouts NS 8 NS 5 Dust Cabbage NS 8 NS 5 Dust
Cauliflower NS 8 NS 5 Dust Celery NS 7 NS 5, NS Dust Corn, Field NS 6 NS 5 Dust Corn, Sweet NS 6 NS NS Dust Corn, Salad NS 7 NS 5 Dust Eggplant NS 10, 16 NS NS Dust
Garlic NS 6 NS NS Dust
Horseradish NS 3 NS NS Dust
Lettuce NS 7 NS 5 Dust Spinach NS 5-7 NS NS-5 Dust Celtuce, Swiss Chard, Chervil, Chrysantemum, Garden & Upland Cress, Dandelion, Dock (Sorrel), Endive (Escarole), Orach (Mountain Spinach), Parsley, Garden Purslane, Winter Purslane, Roquette (Arugula) NS 7 NS 5 Dust

Onion NS 6 NS NS Dust
Fennel NS 7 NS 5 Dust Peppers NS 8 NS NS Dust

5 Current as of 09/29/1020 Table 3.3. Summary of use information for dust a pplications of permethrin, based on a subset of representative labels. Information presented is abridged from the LUIS – EFED Label Data Report 5

Use Single App.
Rate (lb. a.i./A) Number of Apps. Seasonal App. Rate (lbs. a.i./A) Interval
Between Apps. (days) App. Method
Potatoes NS 8-12 NS NS Dust
Tomato NS 6 NS NS Dust
Cucumbers NS 8 NS NS Dust Pumpkin NS 8 NS NS Dust Gherkin, Chinese Gourd (Wax), Gourds, Melons, Bitter Melon, Cantaloupe Melon, Ciron Melon, Honeydew Melon, Musk Melon, Winter Melon, Squash, Summer Squash, Winter Squash (Hubbard) NS 8 NS NS Dust

English/ Black Walnuts NS 8 NS NS Dust
Rhubarb NS 5-7 NS NS-5 Dust Ornamental Shade Trees, Herbaceous & Non-Flowering Plants, Woody Shrubs and Vines NS NS NS NS Dust

Permethrin has uses for the treatment of several ki nds of animals for the control of ectoparasites. They include cattle, dairy cattle (lactating, non-lactating or unspeci fied), dairy goats (lactating, non-lactating or unspecified) and wool/ angora animals, dogs/ canines adult/puppies, cats/ kittens, animal bedding treatment (presumably fo r pets), hogs/ pig/ sw ine treatments, horses (show/ race/ special/ ponies), lives tock, poultry, and sheep animal treatment. Treatments include dips, sprays, sponges, dust, back ru bber, spot treatment, and ear trea tment. For cattle, typically a 14 day retreatment interval was specified. Applied amounts vary per label and are often estimated in lb a.i./animal. Figure 3.1 shows the cattle and calves inventory as of 2007 . Since exposure to water bodies due to treatment of cattle and various other animals is possible, this use will be assessed in the ecological risk assessm ent to estimate potential permethrin exposure following application to livestock.21 Figure 3.1. Cattle and Calves Inventory as of 2007 6

The usage of permethrin, from the Screening Level Usage Analysis (SLUA) is provided in Table 3.4 . The table is arranged by crop in alphabetical order. Accord ing to the table, the major agricultural uses for permethrin are corn (90,000 lb a.i.), fo llowed by lettuce and pistachio (40,000 lb a.i. each), and alfalfa, almonds and soybeans (with 30,000 lb a.i. each). Crops with relatively high percent crop treated ( ≥ 45%) include artichokes, celery, lettuce, pistachios and spinach. Their respective aver age percent crop treated were 45, 60, 45, 65 and 50%. Their maximum percent crops treated were 65, 90, 70, 80 and 75%, respectively. Both lettuce and pistachio, which are crops with high average and maximum percent cr op treated, are among the major crops in terms of pounds of active ingredient applied (with ≥ 30,000 lb a.i. per year).

Table 3.4. Screening-Level Estimates of Ag ricultural Uses of Permethrin (SLUA) 7

Crop Lbs. A.I. Percent Crop Treated Average Maximum

6 Information obtained from the following website accessed 02/01/11: http://www.agcensus.usda.gov/Publications/2007 /Online_Highlights/Ag_Atlas_Maps/Livestock _and_Animals/Livestock,_Poultry_ and_Other_Animals/07-M134.asp

7 Dated 08/24/1022 Table 3.4. Screening-Level Estimates of Ag ricultural Uses of Permethrin (SLUA) 7

Crop Lbs. A.I. Percent Crop Treated Average Maximum Alfalfa 30,000 <2.5 <2.5 Almonds 30,000 15 30

Apples 2,000 5 5 Artichokes 1,000 45 65 Asparagus 2,000 15 25 Avocados 1,000 5 10 Beans, Green <500 <2.5 <2.5 Broccoli 3,000 15 30 Brussels Sprouts* <500 N/C N/C Cabbage 3,000 15 20 Cantaloupes 3,000 15 40

Carrots + 1,000 5 15 Cauliflower 1,000 15 30 Celery 6,000 60 90 Cherries 2,000 5 20 Chicory* + <500 N/C N/C Corn 90,000 <2.5 5 Cotton + 5,000 <1 <2.5 Cucumbers 5,000 10 20 Dry Beans/Peas <500 N/C N/C Eggplant <500 5 10

Garlic 1,000 10 25 Grapes 1,000 <1 <2.5 Hazelnuts (Filbert) + 1,000 5 15 Lettuce 40,000 45 70
Nectarines* <500 N/C N/C Onions 4,000 10 15 Oranges + <500 <1 <2.5

Peaches 8,000 15 25 Peanuts + 4,000 <1 <2.5 Pears 1,000 5 10 Peas, Green + <500 <1 <2.5 Pecans 1,000 <1 <2.5 Peppers 3,000 5 15 Pistachios 40,000 65 80 Potatoes 10,000 5 10

Prunes + <500 <1 <2.523 Table 3.4. Screening-Level Estimates of Ag ricultural Uses of Permethrin (SLUA) 7

Crop Lbs. A.I. Percent Crop Treated Average Maximum Pumpkins 4,000 15 25

Rice+ 1,000 <1 <2.5 Sorghum + 1,000 <1 <2.5 Soybeans 30,000 <1 <2.5 Spinach 9,000 50 75 Squash 2,000 10 20
Strawberries <500 <1 <2.5 Sweet Corn 10,000 10 15 Tobacco + 2,000 <1 <2.5 Tomatoes 6,000 5 10 Walnuts 4,000 5 10 Watermelons 4,000 10 15

All numbers are rounded. '<500' indicates less than 50 0 pounds of active ingredient. '<2.5' indicates less than 2.5 percent of crop is treated. '<1' indicates less than 1 percent of crop is treated. ‘+’ Crops not known to be listed on active end use product registrations or as Section 18 emergency exemptions when the report was run. ‘N/C’ not calculated. ‘*’ CA data only ( 95% or more of U.S. acres in California; data only available on total lbs.A.I.). The sources of the SLUA include the USDA-NASS, Private Pesticide Market Research and California Department of Pesticide Regulation (CDPR) data. The information reflects amalgamated data developed by the Agen cy and are in a releasable format.

BEAD provided agricultural information by states in its Permethrin Chemical Profile for Registration Review: “The states with the mo st agricultural usage in terms of pounds active ingredient applied are: Califor nia (35%), Illinois (7%), and Mi ssouri (6%), followed by Arizona (5%), Wisconsin (4%), and Iowa, Indiana, a nd Minnesota, Nebraska with 3% each.” (GfK Kynetec, 1998-2008 Proprietary Data)

The U.S. Geological Survey (USGS) pesticide ag ricultural use maps show regional scale patterns in use intensity within the United States ( Fig. 3.2 ). The USGS pesticide maps are based on State level estimates of pesticide use rates for indi vidual crops, which have been compiled by the National Center for Food and Agricultural Policy (NCFAP) for 1999 through 2004, and on the 2002 Census of Agriculture for county crop ac reage crop. According to the map, the major agricultural use for permet hrin as of 2002 was corn, with 48% of the national use; this use was followed by lettuce, alfalfa hay and soybeans with 6.8-9.4% of the pounds applied (source: http://water.usgs.gov/nawqa/pnsp/usag e/maps/show_map.php?year=02&map=m6048 , accessed 01/20/11 ) . General agreement exists between the SLUA and the USGS map data. The map shows a generalized use of permethrin for agri cultural purposes througho ut all of the country, with higher use in the Midwest (the cornbelt), California and the Chesapeake Bay region (the Delmarva Peninsula). It also shows potential us es in estuarine/ marine regions of the US. Multiple agricultural uses are approved for permethrin, besides those shown on the map, as indicated above in the Tables 3.2 and 3.3

.24 Fig. 3.2 Estimated Use of Permethrin in 2002

Note of Caution: The pesticide use maps available ( http://water.usgs.gov/nawqa/pnsp/usage/maps/compound_listing.php?year=02 ) show the average annual pesticide use intensity expre ssed as average weight (in p ounds) of a pesticid e applied to each square mile of ag ricultural land in a county. The area of each map is ba sed on state-level estimates of pesticide use ra tes for individual crop s that were compiled b y the CropLife Foundation, Crop Protection Research Institute during based on information collected during 1999 through 2004 and on 2002 Censu s of Agriculture county crop acreage. The maps do not represent a specific year, but rather show typical use patterns over the five year period 1999 through 2004. Use intensity rates are expressed as the pounds applied per square mile of mapped agricultural land in a county. The area of mapped agricultural land for each county was obtained from an enhanced version of the 1992 USGS National Land Cove r Data (NLCD). The ke y limitations of the data used to produce these maps include the following: (1) state use coefficients represent an average for the entire state and consequently do not reflect the local variability of pesticide management practices found within states and counties, (2) pesticide use estimates are not for a speci fic year, but represent typical use patterns for the five year period, (3) state pesticide use coefficients may not have been available for all states where a pesticide may have been applied to agricultural land, and therefore, are not displayed on the maps, (4) the county crop acreage is based on the 20 02 Census of Agriculture and may not represent all crop acreage because of Census nondisclosure rules, and (5) agricultural land area used to calculate the pesticide use intensity and display the data was derived from 30-meter satellite remote sensing data that may over estimate or underestimate the actual agricultural land area. The maps are not intended for making local-scale estimates of pesticide use, such as estimates at the county level. Please refer to Method for Estimating Pesticide Use for a detailed discussion of how the pesticide use data were developed.

Non-agricultural Use Besides the classical agricultural use sites, permethrin has multiple non-agricultural uses. Examples of uses classified as outdoor resi dential include ornamental lawns and turf, recreational area lawns, residen tial lawns and paths/ patios. With respect to the non-agricultural usage, BEAD’s Permethrin Chemical Profile for Registration Review rev eals that, “In terms of non-agricultural usage, data are available to a ddress usage by lawn care operators and pest control operators, and for uses such as mosqu ito abatement, golf courses, nursery/ greenhouse, and food handling establishments, in addition to consumers for outdoor use. Generally, over the25 reported years (1999 through 2008), the majority of use was by consumers for outdoor use. Consumers used 1.6 million pounds active ingredie nt in 2000, approximately 2.5 million pounds active ingredient in 2003, and 1.75 million pounds active ingredient in 2005 for outdoor use. This amount is approximately 4-6 times greater than the average agricultural usage of permethrin which is approximately 400,000 pounds active ingredient/year, based on private market pesticide usage data (Proprietary Data, 1998-2008; based on information provided in the Screening-Level Estimates of Agricultur al Uses of Permethrin, provided by the Biological and Economic Anal ysis Division on 08/24/10). Pest control operators used approximately 580,000 pounds active ingredient in 2000 and 450,000 pounds active ingredient in 2003. Use for mosquito abatement included ap proximately 34,000 pounds active ingredient in 2000, increasing to 100,000 pounds active ingred ient in both 2003 and 2005. Nursery/ Greenhouse use in 2002 was approximately 25,000 pounds active ingredient with use decreasing in 2004 to approximately 14,000 pounds active i ngredient and in 2006 to 12,000 pounds active ingredient (Kline and Co., Inc., 2000-2005).”

Table 3.5 provides a summary of several nonagricult ural (terrestrial or outdoor) uses for permethrin (except for those described in Table 3.2). Application methods vary widely. Note that for various uses, the maximum application rate is expressed in units other than lb a.i./A and in some instances more than one application rate is provided (for example, see “household domestic dwellings outdoor premises”). Many of the uses potentially involve substantive exposure to wildlife, especially aquatic organisms, and they will be assessed accordingly (e.g., conifers – seed orchard, forest tr ees, commercial/ industrial lawns, residential law n, golf course turf, ornamental lawns and turf, recreation area lawns and resident ial lawns). Another use that will be evaluated is wood pr otection treatment (outdoors).

Table 3.5. Summary of terrestrial non-food us es for permethrin (except for the uses identified in Table 3.2)

Use Max. App. Rate/ units Max. No. Applications/
Year Max. App. Rate per

Year Min. App. Interval/

days AGRICULTURAL/FARM PREMISES 1.1 lb/A NS NS 14 AGRICULTURAL/FARM STRUCTURES/BUILDINGS AND EQUIPMENT 0.8 lb/A NS NS 14

ANIMAL KENNELS/SLEEPING QUARTERS (COMMERCIAL) 0.2 lb/A NS NS NS

BARNS/BARNYARDS/AUCTION BA RNS 1.1 lb/A NS NS 14 CABLES/CABLE COVERINGS (VERT. PEST CONTROL) 0.017 lb/linear ft NS NS NS

COMMERCIAL/INSTITUTIONAL/INDUSTRIAL PREMISES/ EQUIPMENT (OUTDOOR) .000094 lb/ linear ft or expressed in lb/gal NS NS NS

EATING ESTABLISHMENTS 0.8 lb/A NS NS NS FENCEROWS/HEDGEROWS 0.04 lb/hole or .016 lb/linear ft NS NS NS26 Table 3.5. Summary of terrestrial non-food us es for permethrin (except for the uses identified in Table 3.2)

Use Max. App. Rate/ units Max. No. Applications/
Year Max. App. Rate per

Year Min. App. Interval/

days HOUSEHOLD/DOMESTIC DWELLINGS OUTDOOR PREMISES 0.1 lb/A; 0.45 lb/A 8 ; 20 lb/A 9 ; 341 lb/A 10 or expressed in lb/ linear ft or lb/gal NS; NS; NS; NS 0.18 lb/A; NS; NS; NS NS; NS; NS; NS

INDUSTRIAL / CONSTRUCTION AREAS (OUTDOOR) 0.1 lb/A; 182 lb/A 11 NS; NS 0.18 lb/A; NS NS; NS LIVESTOCK FEED LOTS 0.46 lb/A NS NS 14 MEAT PROCESSING PLANT PREMISES (NONFOOD CONTACT) 1.6 lb/A NS NS NS-14

MUSHROOM HOUSES-EMPTY PREMISES/EQUIPMENT 0.32 lb/A NS NS NS

NONAGRICULTURAL OUTDOOR BUILDINGS/STRUCTURES 18 lb/A; 180 lb/A 12 NS; NS NS; NS NS; NS
NONAGRICULTURAL UNCULTIVATED AREAS/SOILS 0.86 lb/A NS NS 7

RECREATIONAL AREAS 0.1; 18 lb/A 13 NS; NS 0.18; NS NS; NS REFUSE/SOLID WASTE CONTAINERS (GARBAGE CANS) Expressed in lb/gal 14 NS NS NS

REFUSE/SOLID WASTE SITES (OUTDOOR) 0.1 lb/A NS 0.18 lb/A NS URBAN AREAS 0.8 lb/A NS NS NS UTILITY POLES / RIGHT-OF-WAY 0.017 lb/linear ft or expressed

in lb/gal NS NS NS

WOOD PROTECTION (OUTDOORS) Up to 512 NS NS NS, 30 NS = Not Specified; AN = As Needed; cc = cr op cycle. Data obtained from LUIS Report.

Other uses are classified as Indoor Food, I ndoor Non-Food, Indoor Resi dential or Indoor Medical. They include cattle feedlots, dairy fa rm milk handling facilities/equipment, milking stalls/parlors or stor age facilities, poultry processing plan t premises (non-food contact), pets living/sleeping quarters, eating establishments , food handling areas ( non-food contact), food serving areas (non-food contact), feed mills/feed processing plants, food processing plants and premises non-food handling areas or non-food c ontact, food stores/ supermarkets/ market premises, empty grain/ cereal/flour elevators, hospitals/medical institutions premises (human/ veterinary), commercial transportation facilities, household/domestic dwellings (various), human

8 Hose end sprayer

9 Perimeter treatment

10 Soil treatment (rodding) – injection equipment

11 Soil treatment (preconstruction)

12 Soil treatment (preconstruction)

13 Perimeter treatment

14 Spot treatment27 bedding/mattresses, meat processing plant premises (non-food contact), mushroom houses empty (premises/equipment), non-feed/non-food empty storage areas, non-feed/non-food treatmentsstorage/processing handling equipment, refuse/solid waste sites (indoors), ships and boats. Uses on drainage and sewage systems are clas sified as aquatic non-food industrial.

Permethrin also has uses to treat clothing to prevent insect bites, including military clothes. “Permethrin is registered for use as both an in secticide and a repellent. Permethrin products are used on clothing, shoes, bed nets, and camping g ear. Permethrin-impregnated clothing such as pre-treated shoes, socks, and pa nts repel and kill ticks, mosquito es, and other insects and retain this effect after repeated launde ring. Permethrin is also found in treated tents, tarps, bed nets, sleeping bags, and mattresse s.” (Source accessed 01/21/11: http://www.epa.gov/pesticides/hea lth/mosquitoes/ai_insectrp.htm ).

BEAD’s Chemical Profile for Registration Revi ew indicates that “Permethrin also has nonFIFRA pharmaceutical uses as a pediculicide for the treatment of head lice and scabies. The Food and Drug Administration (FDA) approved us e of the pesticide-co ntaining pharmaceutical under the Federal Food, Drug, and Cosmetic Act ( FFDCA).” Products for such use include both over-the-counter (OTC) and prescribed medications.

The Agency has limited use and usage information relevant to urban exposures and residential uses of pyrethroids, including permethrin. The Agency intends to use available non-agricultural use and usage data, such as the Kline database, the Califor nia Department of Pesticide Regulation’s (CDPR) Pesticide Use Reporting Data and Pest Control Operator’s usage survey, and the Residential Joint Venture Task For ce homeowner survey data (2003), to inform reasonable assumptions regarding various a pplications and information related to urban/residential use and potential environm ental exposure. Detailed information on nonagricultural use and usag e of pyrethroid products, specifically permethrin, would be useful in order to reduce those uncertainties for the fina l environmental risk assessment for permethrin. For example, such information could include usag e data, maximum and typi cal application rates, minimum and typical intervals between appli cation, timing of application (seasonal or throughout the year), number of applications per year, etc. , for the numerous non-agricultural uses of permethrin.

For indoor uses, the Division has conducted environmental risk assessments for a few chemicals for Re-registration Eligibility Decisions (including permethrin, but also resmethrin, pyrethrins, and others). In one open literature study (Wes ton and Lydy, 2010), several synthetic pyrethroids were observed in effluents after secondary tr eatment from POTWs in the Sacramento-San Joaquin Delta. In the study, bifenthrin was th e most frequently detected pyrethroid, while permethrin was found in 33% of the municipal wastewater treatment pl ant effluents (POTWs) tested in the Sacramento-San Joaquin Delta (18 samples tested), at a maximum concentration of 17.2 ng/L, and which exceeded the Hyalella azteca EC 50 of 21.1 ng/L in 0% of the samples. There is the potential for synthetic pyrethroid s to reach surface waters via exposure from contaminated drains, and even after treatment in plants (POTWs). Furthermore, EFED has an unreviewed study which included monitoring of e ffluents from a plant in Suffern, NY (Cleary and McGrath, 2009, study submitted to the Califor nia Department of Pesticide Regulation, CDPR) that confirms the presence of various pyre throids in effluents from the plant. There is28 also an Agency report that identified the presence of permethrin in effluents of 2 out of the 9 POTWs evaluated. 15 EFED will evaluate the potential for exposure to aquatic organisms from the indoor uses of permethrin th rough POTWs in the final ecologica l risk assessment (for further details see Section 6 , Conceptual Model and Section 7 , Analysis Plan).

Permethrin Use with Synergists

Piperonyl butoxide (PBO) and M GK-264 are synergists that are co mmonly used in formulations with permethrin. Two examples include Biomist ® 3+15 ULV which is used for mosquito control and is co-formulated with PBO (EPA Reg No. 8329-33) and Enforcer Ant & Roach Killer III ® which is co-formulated with MGK-264 (EPA Re g. No. 40849-33). PBO acts as a potentiator in both mammals and insects because the pyrethroid is not metabolized and excreted as quickly in its presence (Barile 2004; Hodgson & Smart 2001) . Exposure to pyrethroids along with PBO increases the toxicity of th e pyrethroids to aquatic inve rtebrates (Amweg & Weston 2007; Weston & Lydy 2010). MGK-264, another potentiato r/synergist used with pyrethroids, has similar effects as those observed for piper onyl butoxide (Hodgson & Smart 2001). Permethrin may be co-formulated with either or both s ynergists, PBO and MGK-264, in numerous products.

Available literature data al so suggest the potential for synergism in the environment ( e.g. , Amweg et al. 2006, Weston et al. 2006). It is important to recogni ze that in general, active ingredients and synergists have differing fate properti es and therefore would be expected to occur in the environment at differe nt times and at different concentr ations than present in the end use product.

Currently, data on the degree to which the toxicity of pyrethroid active ingredients is enhanced by varying concentrations of PBO and MGK-264 are needed to address the ecological risk of products when co-applied with PB O or MGK-264. The need for syne rgist data is discussed in the EFED Registration Review Problem Fo rmulation for Piperonyl Butoxide , dated December 13, 2010 (USEPA, 2010, D378420). The PBO Problem Formulation is available in the PBO registration review docket at www.regulations.gov (EPA-HQ-OPP-2010-0498). Based on data on the acute toxicity of pyr ethrin and PBO to target insect spec ies, it is known that the degree of toxicity enhancement increases at higher PBO:pyret hrin ratios (or absolu te concentrations) and that this toxicity enhancement is gr eater than simple additive toxicity. 16 The Agency is currently evaluating a proposed study protoc ol that will quantify the enha ncement of acute toxicity of pyrethrin to the freshwater amphipod, Hyalella azteca , by simultaneous exposure to PBO at varying PBO:pyrethrin ratios. It is expected that this comp rehensive testing strategy, when augmented with similar acute toxicity data with freshwater fish and other selected pesticideactive ingredients, will facilitate bridging of the synergist toxicity enhancement to other coformulated or co-applied pesticid e/synergist activie ingredients th at are not tested at varying synergist: active ingredient ratios. With respec t to evaluating ecological risks from co-applied permethrin and synergists (PBO and MGK-264), th e Agency is requesting acute toxicity studies

15 USEPA 2009, Occurrence of Contaminants of Emerging Concern in Wastewater From Nine Publicly Owned

Treatment Works
, EPA-821-R-09-009, August 2009.
16 Stewart, D. 1998. The Evaluation of Synergis tic Action in the Labor atory and Field. p. 173- 198 In: Piperonyl Butoxide: the Insecticide Synergist. Academic Press.29 of permethrin TEPs that are co-formulated w/ PBO and MGK-264 at the highest synergist:active ingredient ratio. These TEPs s hould correspond to those formulated products that are labeled for outdoor uses and would be conducted with a freshw ater fish and a freshw ater invertebarate. Additional discussion of the need for combined perm ethrin: synergist toxicity data is provided in Section 7.9 (Preliminary Data Gaps). Environmental Mixtures Toxicity data on environmental mixtures of permet hrin with other pesticides may be presented, if available, as part of the ecological risk assessmen t. It is expected th at the toxic effect of permethrin, in combination with other pesticides used in the environment, is likely to be a function of many factors including but not necessarily limited to: (1 ) the exposed sp ecies, (2) the co-contaminants in the mixture, (3) the ratio of permethrin a nd co-contaminant concentrations, (4) differences in the pattern and duration of exposure among cont aminants, and (5) the differential effects of other phys ical/ chemical characteristics of the receiving waters (e.g. organic matter present in sediment and susp ended water). Quantitatively predicting the combined effects of all these variables on mixture toxicity to any given ta xa with confidence is beyond the capabilities of the available data and methodologies. However, a discussion of implications of the available pe sticide mixture effects data re garding the confidence of risk assessment conclusions will be addressed as part of the uncertainty analysis. EFED will consider open literature, currently available models and ot her lines-of-evidence (e. g., monitoring data), as available to address the potential for cumulative effects of pyrethroi ds in the risk description of the ecological assessment for permethrin.

3.3. Environmental Fate and Transport

Permethrin’s structure has three rings, two phenyl rings attached to each other by an oxygen atom, and a cyclopropyl ring. The structure of the molecule has two chiral centers which raise the number of possible isomers to 2 2 = 4. Permethrin consists of a mixture of these four isomers with the configurations [1R, trans ], [1R, cis ], [1S, trans ], and [1S, cis ]. The ratio of cis : trans is around 2:3 and 1R:1S is 1:1 (racemic). The [1R, cis ] isomer is the most insecticidally active of the isomers.

Table 3.6 summarizes the environmental fate/tra nsport properties of permethrin. For information about the physicochemical properties of this compound, refer to Table 3.1a and 3.1b

.

Table 3.6. Summary of Environmental Fate Properties for Permethrin and Degradates

Study Value and unit Major Degradate Minor Degradates MRID #

or Citation Classificatio nof Study

Abiotic Hydrolysis Half-life 1 = Stable, pH 3 Stable, pH 6 125-350 days, pH 9 Major : m -PB-alcohol (15.5%), Minor : cis -/ trans

DCVA (6.5%) 00102043 Acceptable

Air Photolysis Not available N/A N/A N/A30 Table 3.6. Summary of Environmental Fate Properties for Permethrin and Degradates

Study Value and unit Major Degradate Minor Degradates MRID #

or Citation Classificatio nof Study

Atmospheric Degradation Half-life 1 = 0.467 days, estimated for hydroxyl radical N/A EPISuite v.4.0 N/A

Direct Aqueous Photolysis Half-life 1 = 80 days, pH = 5 Major : None; Note: In the supplemental article, cis - and trans

DCVA and m -PBalc are major products with UV light ( λ > 290 nm). 40242801 Supplementa l 17

Soil Photolysis Half-life 1 = 106 days, loam soil Major : None, Minor : m -PBA (1.5%), and m -PBAlc (4.8%) 40190101 Acceptable

Aerobic Soil Metabolism Half-life 1 = 37 days, sandy loam soil Major : CO 2 (34-40% after 6 months), trans

DCVA (10% at 14 DAT), and m -PBA (12- 15% at 30 DAT) Minor : (3-(2,2-dichloro vinyl)-2-methylcyclo propane-l,2- dicarboxylic acid) (8% at 60 days) 42410002 Acceptable 18

Anaerobic Soil Metabolism Half-life 1 = 204 days, sandy loam soil Major : trans -DCVA (13% at 60 days) and

m -PBA (12% at 60 days) 41970601 Acceptable 19

17 Additional information evaluated from Holmstea d, R.L., J.E. Casida, L.O. Ruzo, and D.G. Fullmer. 1978. Pyrethroid photodecomposition: Permethrin. J. Agric. Food Chem. 1978, 26 (3), 590-595; and Ruzo, L.O., R.L. Holmstead, and J. E. Casida. 1976. Photochemical Reactions of Pyrethroid Insecticides. Tett. Lett. 35, 3045, 1976. However, the available study was conducted at a concentration of 0.05-0.06 ppm (solubility of permethrin in water 0.0055 ppm), and up to 91% of AR was in the walls of the test vials during the study. A new study addressing the above mentioned deficiencies is being required.

18 Partially fulfills the data requirement. Only one soil system was tested. Data on three other soil systems are required as per current guidelines.

19 Partially fulfills the data requirement. St udy only lasted 60 days anaerobic incubation, at which time, 65-72% AR was parent permethrin. Furthermore, it was conducted using only one soil. Data on three other soil system s are required as per current guidelines.31 Table 3.6. Summary of Environmental Fate Properties for Permethrin and Degradates

Study Value and unit Major Degradate Minor Degradates MRID #

or Citation Classificatio nof Study

Aerobic Aquatic Metabolism Half-life 1 = Pond water test system from Wilson, NC: 38.2 days (acid label) total system 42.9 days (alcohol label) total system Major : trans -DCVA (20% at 21 DAT) Minor : cis -DCVA (3.7%) and m -PBA (5.7%) 43938201 Acceptable 20

Anaerobic Aquatic Metabolism Half-life 1 = Pond water/sediment system from Lucama, NC: 175 days (acid label) total system 113 days (alcohol label) in total system Overall half-life 1 for the isomers
cis -permethrin 179 days

trans -permethrin 114 days Major : trans -DCVA (20.8% at 90 days), CO 2 (33.8-43.6% by 367 DAT) Minor : cis -DCVA (6.6%), m -PBA (3.2% at 30 days), m -PBalc (0.45% at 30 days) 43982001 Acceptable 21

20 Partially fulfills the data requirement. Treatment rate was 1 ppm, which greatly exceeds the solubility limit of permethrin; furthermore, the study lasted only 30 days, at which time 56-59% AR was permethrin (sum of cis and trans ). Data for two additional water/ sediment systems, one of marine origin are required. The new studies should address th e above mentioned deficiencies besides fulfilling current guideline s which indicate that at least two water/sediment systems are required.

21 Partially fulfills the data requirement. The st udy was performed at a conc entration that greatly exceeded the solubility limit of permethrin (1 ppm v. 0.0055 ppm). In order to promote anaerobicity, glucose was added to the sediment /water system; however, no redox potential was measured to confirm that the system was fully anaerobic. Furthermore, only one sediment system was evaluated while curre nt guidelines require at least two. A new study is required; since there is the potential to use permethrin near marine/estuarine areas, one of the test systems should be conducted with water/sediment of mari ne origin. The new st udies should address the above mentioned deficiencies besides fulfilling curre nt guidelines which indi cate that at least two water/sediment systems are required.32 Table 3.6. Summary of Environmental Fate Properties for Permethrin and Degradates

Study Value and unit Major Degradate Minor Degradates MRID #

or Citation Classificatio nof Study

Permethrin

, Solid-water distribution coefficient (K d ) K d , soil texture 140 L/kg, sand 217 L/kg, sandy loam 236 L/kg, silty loam 246 L/kg, clay loam 401 L/kg, sandy loam sediment N/A 41868001 Supplementa l 22

Permethrin

,Freundlich solidwater distribution coefficient (K F ) K F , 1/n, soil texture 446 L/kg, 1.32, sand 355 L/kg, 1.12, sandy loam 344 L/kg, 1.09, silty loam 378 L/kg, 1.10, clay loam 1,517 L/kg, 1.29, sandy loam sediment N/A 41868001 Supplementa l

Permethrin

, Organic-carbon normalized distribution coefficient (K OC ) K OC , soil texture 60,900 L/kg, sand 20,900 L/kg, sandy loam 19,300 L/kg, silty loam 20,500 L/kg, clay loam 25,500 L/kg, sandy loam sediment N/A 41868001 Supplementa l

22 Study was performed at concentrations of 0.05 to 0.55 ppm, compared to a solubility limit of 0.0055 ppm in water. Furthermore, a cosolvent concentration of 5% (acetonitrile) was used, compared to a recommended ≤ 0.1%. Even though correlations were good (r 2 ≥ 0.966), the 1/n values varied from 1.09 to 1.32, with only one of them within the recommended range of 0.9-1.1. Extensive degradation occurred particularly for the aquatic sediment. In another study, considered supplemental (MRID No. 45170102, not reported in the Table 3.6 ), the adsorption coefficients were much higher than for the supp lemental study. For the later study, for three of the soils the texture was the same (sandy loam ), the soils were sterilized using gamma irradiation, and the test was perfor med at above the solubility limit. However, the cosolvent used was also acetonitrile at a lower concentration of 0.25% (recommended ≤ 0.1%). And the highest test concentration was 0.2 ppm (solubility in water of 0.0055 ppm), which may promote adsorption. A new study addressing all the above mentioned deficien cies is being required for permethrin.33 Table 3.6. Summary of Environmental Fate Properties for Permethrin and Degradates

Study Value and unit Major Degradate Minor Degradates MRID #

or Citation Classificatio nof Study

Permethrin

, Freundlich organic-carbon normalized distribution coefficient (K FOC ) K FOC , 1/n, soil texture 194,000 L/kg, 1.32, sand 34,100 L/kg, 1.12, sandy loam 28,200 L/kg, 1.09, silty loam 31,500 L/kg, 1.10, clay loam 96,600 L/kg, 1.29, sandy loam sediment N/A 41868001 Supplementa l

m -PBA

,Freundlich solidwater distribution coefficient and organic carbon normalized distribution coefficient (K F and
K FOC ) K F = 0.98 to 3.11 L/kg
K FOC = 118 to 215 L/kg In sand, silt clay, clay, sandy loam, and another sandy loam soils N/A 43424901 Acceptable

trans -DCVA

,Freundlich solidwater distribution coefficient and organic carbon normalized distribution coefficient (K F and
K FOC ) K F = 0.16 to 0.54 L/kg
K FOC = 18 to 48 L/kg In sand, silt clay, clay, sandy loam, and another sandy loam soils N/A 43424901 Acceptable

Volatility from Soil (Laboratory) Study was waived N/A N/A Waived

Volatility from Soil (Field) Study was waived N/A N/A Waived

Terrestrial Field Dissipation Dissipation Half-life 1,2 = Bareground plots 17 days, NC silt loam soil, and 43 days IL silty clay soil Observed : trans -DCVA and m -PBA at both NC and IL sites 42359109 Acceptable34 Table 3.6. Summary of Environmental Fate Properties for Permethrin and Degradates

Study Value and unit Major Degradate Minor Degradates MRID #

or Citation Classificatio nof Study

Aquatic Field Dissipation Dissipation Half-life 1,2 = Pond water, California 1.8/ 1.4 days from the pond water for cis -/ trans

permethrin; 118/ 18 days from the sediment top 2” for cis -/

trans -permethrin Observed : cis -DCVA,

trans -DCVA and m

PBA dissipated fromthe water with halflives of 28, 22 & 7.5 days, respectively. Not detected in sediment. 44030501 Acceptable

Dissipation Half-life 1,2 = Pond water, North Carolina 3.1/ 1.4 days from the pond water for cis -/ trans

permethrin; 156/ 62 days from the sediment top 2” for cis -/

trans -permethrin Observed : cis -DCVA,

trans -DCVA and m

PBA dissipated fromthe water with halflives of 33, 23 & 14 days, respectively. Not detected in sediment. 44034101 Acceptable

Bioconcentration Factor (BCF) – Bluegill Sunfish ( Lepomis macrochirus ) Steady State BCF= 570-610 L/kg wet wt whole fish 180-230 L/kg wet wt edible tissue 950-1,100 L/kg wet wt nonedible tissue Depuration: 4.7 days for 50% depuration Only trans -DCVA was identified, at 4-10% of the total radioactivity 41300401, 41300402, 41300403 Acceptable

Abbreviations: wt=weight; NA=Not Av ailable; N/A=Not Applicable. 1 Half-lives were calculated using the single-first order equa tion and nonlinear regression, unless otherwise specified. 2 The value may reflect both dissip ation and degradation processes.

As shown in Table 3.6 , permethrin is stable to hydrolysis at pHs 3-6, and it degrades at a slow rate (t 1⁄2 = 125-350 days) in alkaline solutions (pH 9) at 25°C in the dark. The hydrolysis products were m -PB-alcohol and cis- DCVA /trans -DCVA. In contrast, permethrin did not appear to degrade subs tantially for a period of 30 days (e xtrapolated half-life 106 days) on a loam soil following irradiation with a xenon arc lamp at 25°C. The reported half-life of 14 Cpermethrin in soil under aerobic so il conditions was 37 days, with 14 CO 2 , trans -DCVA and m

PBA being the major degradation products. It was noted that the trans -isomer of permethrin degraded at a faster rate when compared to the cis -isomer. Furthermore, the degradation of permethrin was biphasic, with faster degrada tion from 0-90 days; howev er, a half-life for the second phase was not provided. A separate supp lemental aerobic biodegradation study showed that of three factors: application rate, moisture percent and application volume, the first one had the greatest effect on the rate of dissipation of permethrin (in th e review, it was speculated that35 possibly the microbial activity was inhibited due to toxicity or the solubility may have been exceeded) when permethrin was applied to aerobi c soil at fortification levels similar to the maximum application rate for terrestrial non- food uses (MRID No. 41970602, results not shown in Table 3.6 ). The study lasted a short time (32 da ys) and only three sampling points were taken (0, 14 and 32 days). In an aerobic aquatic me tabolism study, the reported half-life ranged from 38 to 43 days (the study lasted only 30 days). In this study, trans -permethrin yielded shorter half-lives than the cis -permethrin. The half-life in the anaerobic soil metabolism study was 204 days (in a study that lasted 30 aerobic and 60 anaerobic days) and major degradates were trans

DCVA and m -PBA. The half-lives reported for permet hrin in an anaerobic aquatic study ranged from 113 days to 175 days, which indicates that the degradation in soil and water/sediment systems is slower as the oxygen levels are re duced. Inspection of the available metabolism studies shows that high levels of non-extract ed residues were observed in some studies ( e.g. nonextracted residues reached ~15-35% in the aer obic soil metabolism study at or after 30 days posttreatment; however, adequate attempts were made to extract the residues in such instance).

Permethrin was hardly mobile to immobile (acco rding to the FAO mobility classification) in several soils tested, bot h sterile and viable (K FOC > 10,000 L/kg). K FOC values in the range of 28,000 to 194,000 L/kg were measured in four soils and one sediment sample. Even though the study was found to be acceptable, several defici encies were found upon a cursory inspection and it was downgraded to supplemental (see footnote in Table 3.6 ). Various literature articles document the possibility of de sorption of pyrethroids from impervious surfaces despite pyrethroids strong sorption ( e.g. see Jiang et al . (2010), Jorgenson and Young (2010), and Jiang et al. (2011)). In the latter ar ticle, the model pyrethroid permethrin was used on concrete surfaces. Among their findings, the authors reported that the permethrin desorption from such surfaces decreases with sorption time. This was attributed to the possible alkaline decomposition of the test substance on the concre te surface. The authors indicated that there is the potential for extended contamination due to permethrin treated surfaces.

In contrast, the main degradates of permethrin, m -PBA and trans -DCVA were shown to have a much higher potential for mobility in the soils tested [K FOC s for m -PBA range = 118 to 215 L/kg (moderately mobile) and for trans -DCVA range = 18 to 48 L/kg (mobile)]. Based upon its low Henry’s Law constant and vapor pressure, permet hrin is expected to have a relatively low potential for volatilization from soil and water surfaces.

Acceptable terrestrial field dissipation studies show ed that permethrin degr aded in the field with half-lives ranging from 17 days in a North Carolina fi eld to 43 days for a field located in Illinois. These studies were conducted at th e terrestrial food use rate of 0.4 lb a.i./A. Neither parent nor its two principal soil degradates ( trans -DCVA and m -PBA) were detected (detection limits 2.5 μg/kg) below a depth of 6-inches at either site. More rapid dissi pation rates of permethrin were reported in a study measuring permethrin concen trations in environmental components of a boreal plantation forest in Ontario, Canada treat ed with an aerial spray of permethrin. Permethrin concentrations in soil and forest fl oor litter ranged from 25 to 7 μg/kg and 33 to 18 μg/kg, respectively, during the 4 da ys after application (Sundaram, et al. , 1992). These concentrations represent measurements taken 1 hour to 4 days after the ap plication of 0.06 lb of permethrin per acre (detection lim its 2 μg/kg) Permethrin appeared to persist in forest litter longer than in soil. Ten days af ter application, permethrin was not detected in soil while 8 μg/kg36 of permethrin were det ected in forest litter.

An acceptable aquatic field dissipation study empl oying a site in North Carolina, and a second site in California showed that permethrin dissi pated (moved) rapidly from the water column by binding to suspended solids and sediment. At both sites cis -/ trans -permethrin appeared to be immobile and remained in the uppermost layer (0-2 -inch fraction) of the sediment. There were no detects of metabolites in se diment. In North Carolina, cis - and trans -permethrin were removed from the water surface with half-lives of 3.1 and 1.9 days, respectively. In sediment the reported degradation half-lives for cis - and trans -permethrin were 256 and 62 days, respectively. In California, cis - and trans -permethrin were removed from the water surface with half-lives of 1.8 and 1.4 days, respectively. In sediment the reported degradation half-lives for cis - and trans

permethrin were 118 and 18 days, respectively.

Acceptable fish bioconcentration studies, conducted in bluegill sunfish, showed that permethrin bioconcentrated with factors of 950 – 1100x in viscera, 570 – 610x in the whole fish, and 180 – 230x in the fillet. Depuration occurred at a moderate rate, with 73- 83% depuration occurring after 14 days and 4.7 days for 50% depuration.

Potential transport mechanisms for a pesticide include surface water r unoff, spray drift, and secondary drift of volatilized or soil-bound residues leading to deposition onto nearby or more distant ecosystems. Surface water runoff and spray drift are expected to be the major routes of exposure for permethrin to non-targ et organisms. The magnitude of transport via secondary drift depends on the permethrin’s ability to be mobili zed into air and its eventual removal through wet and dry deposition of gases/ part icles and photochemical reactions in the atmosphere. Therefore, physicochemical properties of permethrin that descri be its potential to enter the air from water or soil ( e.g., Henry’s Law constant and vapor pressure), pesticide use data, modeled estimated concentrations in water and air, and available air monitoring data are considered in evaluating the potential for atmospheri c transport of permethrin. Permet hrin has a low vapor pressure (1.48
x 10 -8 mmHg) and Henry’s Law constant (1.4x10 -6 atm-m 3 /mol); thus, volatilization from water and soil surfaces is expected to be very low. Permethrin’s potential for volatilization is also reduced significantly because it adsorbs strongly to soils. Permethrin’s estimated atmospheric half-life is short (~0.5 days for the hydroxyl ra dical reaction), indicating a low potential for transport via volatilized active substance (as opposed to present in suspended solids).

Limited atmospheric monitoring in California 23 was conducted in Butte, Monterey and Santa Barbara Counties. Application air monitoring was conducted in Butte County and ambient air monitoring was conducted in Monterey County (bot h in 1997). Of 24 application samples in Butte County, three were above the LOQ (LOQ = 0.33 μ g/sample, equivalent to 0.015 μ g/m 3 for 24 hour sampling at 15 L/min). Th e highest concentration was 0.57 μ g/m 3 . Ambient samples were taken in populated areas of Monterey County that coincided with the use of permethrin on lettuce and celery. Of the 115 samples collect ed, six were reported as “detected” and 109 samples were below the LOD (LOD = 0.10 μ g/sample). Monitoring samples were taken in Lompoc, an agricultural city in Santa Barbara County in 2000, fo r a total of 31 pesticides. Permethrin was detected at trace levels to 4.3 ng/m 3 (highest 1-day air concentration).

23 http://www.cdpr.ca.gov/docs/emon/pubs/tac/permthrn.htm (accessed 02/04/11).37 4. Receptors

4.1. Aquatic and Terrestrial Effects

The receptor is the biological entity that is exposed to the stressor (EPA, 1998). Due to the outdoor uses of permethrin, the t ypes of receptors that may be exposed include both aquatic and terrestrial receptors, such as birds, rep tiles, mammals, amphibians, freshwater and estuarine/marine fish, non-target terrestrial & aquatic invertebrates and terrestrial & aquatic plants. This list may not be comprehensive. Spray drift and runoff exposures are expected for both ground and aerial applications of permethrin. Consistent with the process described in the Overview Document (USEPA, 2004), this risk assessment uses a surrogate species approach in its evaluation of permethrin. T oxicological data generated from surrogate test species, which are intended to be representative of broad taxonomic groups, are used to ex trapolate to potential effects on a variety of species (receptors) included under these taxonomic groupings.

Tables 4.1, 4.2 and 4.3 provide a summary of the taxonomic groups and the surrogate species tested to help understand potential acute ecologi cal effects of pesticides to these non-target taxonomic groups. In addition, the tables provide a preliminary overview of the potential acute toxicity of permethrin, by providing the acute toxicity classifications.

Terrestrial Species

Acute toxicity to terrestrial birds and mammals is categorized using the following classification system (U.S. EPA, 2004). Toxicity categories fo r terrestrial plants ha ve not been defined.

Toxicity Category Oral LD 50 Dietary LC 50 Very highly toxic < 10 mg/kg < 50 ppm Highly toxic 10 - 50 mg/kg 50 – 500 ppm Moderately toxic 51 - 500 mg/kg 501 - 1000 ppm

Slightly toxic 501 - 2000 mg/kg 1001 - 5000 ppm Practically non-toxic > 2000 mg/kg > 5000 ppm

Acute toxicity to terrestrial invertebrates is ca tegorized using the following classification system (USEPA, 2004).

Toxicity Category Acute LD 50 Highly toxic < 2 μg ai/bee Moderately toxic 2 – 10.99 μg ai/bee Practically non-toxic ≥ 11 μg ai/bee38 Table 4.1 Summary of most sensitive endpoints fr om submitted terrestria l toxicity studies for permethrin.

Species
(common

name) Taxa Represented Endpoint Concentration Test Substance

(% a.i.) MRID/

Citation Acute Toxicity Classification

Rattus norvegicus
(Laboratory Rat) Mammals LD 50 340.5 mg/kg bw 94 Cantalamessa 1993
(ECOTOX Ref. # 74863) Moderately

Mouse
( Mus musculus ) NOAEL 4.9 mg ai/kg bw/day

94 Farag et al. 2006
(ECOTOX Ref. # 100119) Not Applicable LOAEL 9.8 mg ai/kg bw/day

Mallard duck ( Anas platyrynchos )

Birds, terrestrialphase amphibians, and reptiles LD 50 >2000 mg ai/kg bw 94.4 41888401
Acceptable Practically non-toxic

Bobwhite quail ( Colinus virginianus ) LC 50 >5200 mg ai/kg diet 93.4 41888403
Acceptable Practically non-toxic

Mallard duck ( Anas platyrynchos ) NOAEC 125 mg ai/kg diet

95.2 42322902
Acceptable Not Applicable
LOAEC 500 mg ai/kg diet

Apis mellifera

(Honey bee) Terrestrial invertebrates Contact
LD 50 0.024 μg a.i./bee 93.1 42674501
Acceptable Highly toxic

Mammals Typically, mammalian toxicity data from the Agen cy's Health Effects Division (HED) are used to approximate toxicity to mammals. Wild ma mmal toxicity tests may be required on a case-bycase basis, depending on the results of the lower ti er studies such as acute and sub-acute testing, intended use pattern, and pertinent environmental fate characteristics. No studies evaluating toxicity to wild mammal species have been submitted by the registrants for permethrin.

There is one registrant submitted acceptable rat acute oral toxicity study discussed in the HED chapter of the Reregistration Eligibility Decisi on Document (RED) for permethrin (Dated April
4 th 2006; DP Barcode D324993). Th e reported laboratory rat LD 50 value for the technical active ingredient of permethrin for females was 2280 mg a.i./kg-bw (3580 mg a.i./kg-bw for males) (MRID 00242899). In addition to the data reported to HED, an LD 50 value of 8900 mg a.i./kg-bw for acute oral toxicity of the permethrin tech nical active ingredient to laboratory rats was39 reported in the EFED chapter of the RED for permethrin (Dated April 5 th 2006; DP Barcode D326784). No additional information could be found in the chapter or in the EFED files (No MRID; Document Reference No. 279-GNRU, 1978).

Following the completion of the EFED and HED chapters written for the RED in 2006, additional acceptable acute oral toxicity data with the technical active ingr edient of permethrin (92% a.i.) have been submitted to the Agency (MRID 44707301). The reported laboratory LD 50 value for the technical active ingred ient of permethrin for female rats (6-8 weeks old) in this study was 570 mg a.i./kg-bw (703 mg a.i./kg- bw for males; 614 mg a.i./kg-bw combined)

.

In addition to the registrant data, more sensitive acute toxicity data for mammals were identified in the open literature were used for quantitat ive risk estimation purposes in the 2008 endangered species assessment (EPA, 2008a). Cantalam essa (1993; ECOTOX Re f # 74863) reported 24- hour LD 50 values of 340.5 (95% CL = 308.8-375 .6), 399.0 (95% CL = 346.1-460.0), 471.0 (95% CL = 384.5-577.0), and 1500.0 (95% CL = 938.0-2345.3) mg/kg-bw for 8-day old, 16-day old, 21-day old, and adult rats. LD 50 values and associated confiden ce intervals were determined by using ten animals per dose level, with individuals in four or mo re dose levels being exposed to permethrin (94% purity). Based on th e range of reported laboratory rat LD 50 values from this study, permethrin can be classified as moderately toxic to slightly toxic to small mammals on an acute oral basis.

In the HED chapter of the RED for permethrin (Dated April 4 th 2006; DP Barcode D324993) one registrant-submitted acceptable/guideline three generation reproduction study (MRID 92142092, 120271, 92142037) with rats was discussed. In th is study, permethrin (purity, 94.0-98.8%) was administered to groups of 12 male and 24 female rats in the diet at concentrations of 0, 500, 1000, or 2500 ppm (0, 25, 50, and 125 mg/kg/day, re spectively, using a standard conversion factor of 0.05). The LOAEL for systemic t oxicity is 2500 ppm (125 mg/kg/day) based on tremors observed in the F0 females, and the F1 a nd F2 males and females. The systemic toxicity NOAEL is 1000 ppm (50 mg/kg/day). Th e reproductive toxicity NOAEL is ≥ 2500 ppm (125 mg/kg/day) and the reproductive toxicity LOAE L is not identified. The NOAEL for offspring growth and development is ≥ 2500 ppm (125 mg/kg/day) and th e offspring LOAEL is not identified. However, one of the major defi ciencies noted for this study was a lack of homogeneity and stability of th e compound in the test diets, suggesting that the estimated exposure levels may be unreliable.

In addition to the three generation rat reproductio n study, the other studies were discussed in the HED RED chapter that demonstrated adverse eff ects on growth or reproduction of mammals at more sensitive quantifiable levels. These stud ies included an acceptable/guideline prenatal developmental study with rats (MRID 40943603) a nd an acceptable/guideline chronic oral toxicity study with dogs (MRID 00129600). In the developmental study with rats, the maternal toxicity NOAEL and LOAEL were 50 mg/kg/day and 150 mg/kg/ day, respectively, based on clinical signs of toxi city and decreased body weight gain and food consumption. The dog chronic oral toxicity NOAEL and LOA EL were 50 mg/kg/day and 150 mg /kg/day, respectively, based on decreased fetal body weight. However, mean lit ter weight of the150 mg/kg/day group was 3% (n.s.) greater than that of the controls. Theref ore, the reduced fetal body weights were considered a questionable toxic response.40 In addition to the registrant-submitted data, more sensitive mammalian reproduction toxicity data considered for quantitative risk estimation pur poses for mammals were identified in the open literature in the 2008 enda ngered species assessme nt (EPA, 2008a). Farag et al. (2006; ECOTOX Ref # 100119) reported a NOAEL of 4.9 mg/kg-bw/d ay in mice based on increased number of dead pups, decreased number of live pups, decrea sed body weight and body weight gain in pups, and decreased maternal body weight s. While no significant effects we re noted in the lowest test group of 4.9 mg/kg-bw/day as compared to the cont rol, significant adverse effects were noted in both the 9.8 mg/kg-bw/day and 19.6 mg/kg-bw/day treatment groups. At the LOAEL of 9.8 mg/kg-bw/day, maternal body weight gain decreased during gestation ( ↓ 57% from controls) and lactation ( ↓ 187% from controls), the numb er of dead pups increased ( ↑ 64% from controls), the number of live pups decreased ( ↓ 10% from controls), and body weight gain of pups was decreased ( ↓ 52% from controls).

Birds The results of the acute oral t oxicity studies available for perm ethrin indicate that it can be classified as practically non-toxic to avian sp ecies on an acute oral basis. The acute oral LD 50 values for mallard ducks ( Anas platyrhynchos ), Japanese quail ( Coturnix coturnix ) and ringnecked pheasants ( Phasianus colchicus ) range from >2,000 to >23,000 mg a.i./kg-body weight (MRIDs 41888401, 00042142, 00042121, 00042120).

One study has been submitted to the Agency examining the effects of permethrin on passerine species of birds. A permethrin (PP 557, 92% w/ v active ingredient) acute oral limit test was conducted on starlings ( Sturnus vulgaris ) (MRID 00042144). The test consisted of a vehicle control (3 mL corn oil) and a 29,440 mg a.i. /kg body weight dose le vel (32,000 mg PP 557/kg body weight). The OSCPP 850.2100 guideline for avian acu te oral testing stat es that a limit test may be conducted in lieu of a defi nitive test at 2,000 mg a.i./kg bw level, if 10 birds are dosed and no mortality occurs. No mortality was observe d in the control or treatment group during the test, nor any differences in food consumption or body weight. No regurgi tation was reported, and all birds appeared to remain in good health. Th is study was previously classified as invalid because only a summary of the test was s ubmitted. Upon additional review of the full study report, this test is classified as invalid due to lack of info rmation in the full study report, including documentation that re gurgitation was examined after th e initial dose and that food was withheld prior to dosing. Therefore, this test does not meet the Agency data requirements for a passerine acute oral study with permethrin.

The results of the sub-acute dietar y toxicity studies available for pe rmethrin indicate that it can be classified as practically non-toxic to avia n species on an subacute dietary basis with LC 50 values for mallard ducks ( Anas platyrhynchos ), Northern bobwhite quail ( Colinus virginianus ), Japanese quail ( Coturnix japonica ) and ring-necked pheasants ( Phasianus colchicus ) ranging from >5,200 to >23,000 mg a. i./kg-diet (MRID 00112939, 41888403, 41888402, 00072845, 00042123, and 00043733, and ACC# 227722).

Four avian reproduction studi es with mallard ducks ( Anas platyrhynchos ) and Northern bobwhite quail ( Colinus virginianus ) have been submitted to the Agency for permethrin (MRID 00110670,41 00110671, 42322901, and 42322902). In three of the four studies, there were no observed adverse effects on any of the endpoints including food consumption, number of eggs laid, eggs cracked, egg shell thickness, vi able embryos, live three-week embryos, normal hatchlings, 14- day-old survivors and offspri ng body weight (MRID 00110670, 00110671, 42322901). One study with bobwhite quail (MRID 42322901) esta blished a LOAEC at the highest tested concentration of 500 mg a.i./kg- diet (LOAEC>500 mg a.i./kg-diet). The other two studies with no observed adverse effects on bobwhite quail (MRID 00110671) and mallards (MRID 00110670) only tested up to 25 mg a.i./kg-diet (NOAEC=25 mg a.i./kg-diet, LOAEC>25 mg a.i./kg-diet).

In a permethrin avian reproduction study with mallard ducks, there was a decrease in food consumption and an overall decrease in egg production ( ↓ 13.2%) at 500 mg a.i./kg-diet (MRID 42322902). Although these effects were not statistically signif icant, they were associated with an apparent increase in the number of hens w ith a regressed ovary. The NOAEC and LOAEC for this study are 125 and 500 mg a.i./kg-diet, respectiv ely. The results of th is study indicate that permethrin may have adverse e ffects on avian reproduction at highe r levels of chronic exposure.

Terrestrial Invertebrates The Agency guideline terrestrial inverteb rate toxicity tests are for honey bees ( Apis mellifera ). A total of six studies that include acute contact, acute or al, and acute contact with treated foliage
LD 50 values for permethrin techni cal grade active ingredient (TGA I) and formulated permethrin and honey bees (MRIDs 42674501, 00045044, 00045046, 42674501, 42009301) have been submitted for permethrin. The acute contact LD 50 values range from 0.024 (with TGAI) to 0.16

μ g a.i./bee (with formulation), the acute oral LD 50 ranges from 0.13 to 0.19 μ g a.i./bee (both with TGAI), and the single treated foliage study (tr eated with formulation Ambush 25W) reports an
LD 50 value of < 0.2 lb a.i./A. Based on these results, permethrin is classified as ‘highly toxic’ to honey bees on an acute exposure basis.

In addition to the guideline studies with hone y bees, a number of other older studies with terrestrial invertebrates and fo rmulated permethrin are availa ble to the Agency. Many of the studies have little information re ported and the results are presented below as they are in the studies. One acute contact 5-day study with various species of pa rastitic wasps (MRID 05009995) demonstrates a range in sensitiv ity of the five tested species ( Apanteles sp.

, Opius bruneipus

, Telenomus remus, Copidosoma truncatellum , and Diglyphus intermedius ), with mortality ranging from 0% to 85% at 0.1 lb a.i. /A, and 40% to 100% at 0.2 lb a.i./A. A study with alkali bees ( Nomia melanderi ) exposed to foliage treated with formulated permethrin reported mortality ranging from 25% to 78% at rate s ranging from 0.5 oz. a.i./A to 2 o.z. a.i./A, respectively (NR 1975). Another study with alfalfa leafcutter bees ( Megachile rotundata pacifica ), exposed to foliage treated with formulated permethrin reported mortality ranging from 24% to 88% at rates ranging from 0.5 oz. a.i. /A to 2 o.z. a.i./A, respectively (ICI US1975). In other studies with mites ( Amblyseium fallacis ), convergent ladybeetles ( Hippodamia

convergens ), and predatory mites ( Metaseiulus occidentalis ) acutely exposed to formulated permethrin, LD 50 values ranging from <0.5 to 15.5 ppm a.i. were reported (MRID 00045048, 05009995, 00045048, ICI US 1975, ICI US 1976, ICI US NR).42 Open literature studies on permethrin acute contact toxicity to terrestrial insects were obtained via the USEPA ECOTOX database and screened for acute toxicity endpoints that were more sensitive than the acute LD 50 endpoint obtained from submitted data on the honeybee (i.e., 0.024 ug a.i./organism or 0.1875 ug a.i./g-organism; MRID 42674501) . The ECOTOX database contained laboratory-ba sed, acute contact LD 50 results for species in f our Orders in the Class Insecta: Hymenoptera, Coleopter a, Lepidoptera, and Diptera.

. Based on this information, it appears that honeybee represents reasonably the sensitivity of th e more sensitive terrestrial invertebrates in the context of acute, c ontact permethrin toxicity (US EPA 2010).

Based on several considerations, the need for additional permethrin toxicity or exposure data for pollinators was evaluated. First, permethrin is a non-systemic insecticide with respect to its uptake and distribution in terrestrial plants. Therefore, concerns ove r potential exposure of pollinators to permethrin can be mitigated for crops with flowering via restrictions on the timing of application in relation to bee foraging activity.

Second, data from the open literature were review ed for estimating potential exposure and effects of permethrin to pollinators, particularly for re sidues in hives and effects on endpoints other than mortality (e.g., reproduction, beha vior effects per 40 CFR Part 158). Specifically, Mullin et al. (2010) recently reported pesticid e residues in bee, pollen a nd wax samples from managed apiaries with unknown pesticide exposur e history. In their study, Mullin et al reported residues of permethrin ranging from 12 to 19600 ppb in immatu re and adult bees (5.7% detection in 140 samples), 9.6 to 92 ppb in pollen (2.6% detecti on in 350 samples) and 31-372 ppb in wax (1.9 % detection in 258 samples). Based on pollen consum ption estimates of 6.5 mg pollen/bee/day for nurse bees obtained from the open literature (Rotais et al 2005), these maximum concentrations reported in pollen and wax result in es timated 2-day exposures of about 1/100 th to 1/25 th the acute 48-h oral LD 50 value of 0.13 μg ai/bee. The extr aordinarily high permethrin residues reported in worker bees (nearly 20 mg ai/kg be e) are reportedly derived from a permethrin bee kill incident, according to the author’s study. Under greenhouse conditions, Cox and Wilson (1984) reported that abdominally-administe red permethrin at 0.009 ug ai/bee resulted in mortality and failure of worker bees to return to the hive when simultaneiously exposed to naturally fluctuating temperatures (15-35C). Th e authors also reported behavorial changes of worker bees when exposed abdominally to perm ethrin at 0.001 ug ai/bee. In another study, Dai et al. (2010) examined the sublethal effects of two other synthetic pyrethroids, i.e ., deltamethrin and bifenthrin, on bee colony health when admini stered via water:sucrose solution for worker bees (6.1 and 29.6 mg ai/L) and directly to queens (5 ul/queen) for 20 days. The authors concluded that exposure to each of these chemicals (at approximately the LD 05 ) adversely impacted bee reproduction by reducing bee fecundity and decreasing the rate of bee development into adulthood.

A third consideration for the need for additional pollinator data is the current state of the science regarding pollinator risk assessment. Specifi cally, the Agency acknowledges that several scientific activities related to pollinator risk assessment practices and data needs are currently pending or under developmen t (e.g., the report from the 2011 SETAC-Pellston workshop on pollinator risk assessment and a FIFRA Scientific Advisory Panel (SAP) review of this same topic planned for spring of 2012).43 Therefore, in consideration of the aforemen tioned information concerning the non-systemic nature of permethrin foliar residues and subsequent risk mitigation options, the nature of residues reported in pollen, wax and bees, and further deve lopment of pollinator risk assessment methods and guidelines, the Agency is not requesting additional data on permethrin exposure and effects on pollinators as part of this preliminary Problem Formulation. Instead, the Agency is placing the need for additional data “In Reserve” pending the outcome of the aforementioned scientific activities, comments from stakeholders on the need for additional data, and the review of additional information concerning th is topic. Specifically, the Agency requests that stakeholders submit additional scientific information on the exposure and effects of permethrin to pollinators not considered in this prem inalry problem formulation.

Aquatic Species

Toxicity to fish and aquatic i nvertebrates is categorized using the the following system (U.S. EPA, 2004). Toxicity categories for aqua tic plants have not been defined.

LC 50 (ppm) Toxicity Category < 0.1 Very highly toxic > 0.1 - 1 Highly toxic > 1 - 10 Moderately toxic > 10 - 100 Slightly toxic > 100 Practically nontoxic

Table 4.2 Summary of most sensitive endpoints from submitted aquatic toxicity studies for permethrin.

Species
(common

name) Taxa Represented Endpoint Concentration (ug a.i./L) MRID Acute Toxicity Classification

Bluegill Sunfish
( Lepomis macrochirus ) Freshwater Fishand Aquaticphase Amphibians LC 50 0.79 00042128
Supplemental Very highly toxic

Fathead Minnow
( Pimephales promelas ) NOAEC 0.30 1 00110666
Acceptable Not Applicable

LOAEC 0.41

Waterflea ( Daphnia

magna ) Freshwater Invertebrates EC 50 0.039 2 MRID 00043736
Acceptable Very highly toxic

Waterflea ( Daphnia

magna ) NOAEC 0.039 3 MRID 43745701
Acceptable Not Applicable LOAEC 0.08444 Table 4.2 Summary of most sensitive endpoints from submitted aquatic toxicity studies for permethrin.

Species
(common

name) Taxa Represented Endpoint Concentration (ug a.i./L) MRID Acute Toxicity Classification

Atlantic Silverside ( Menidia menidia ) Estuarine/Marine Fish LC 50 2.2 40228401
Supplemental Very highly toxic

Sheepshead

Minnow ( Cyprinodon variegatus ) NOAEC 10 4 41068007

Unreviewed Not Applicable LOAEC 22

Stone crab ( Menippe
mercenaria ) Estuarine/Marine Invertebrates EC 50 0.018 40228401
Supplemental Very highly toxic

Mysid shrimp ( Americamysis bahia ) NOAEC 0.011 5 41315701
Acceptable Not Applicable LOAEC 0.024

1 In the latest Agency risk assessment that looked at perm ethrin effects to aquatic speci es (US EPA 2008a), the chronic NOAEC for freshwater fish was estimated to be 0.0515 μg a. i./L using an acute-to-chronic ratio (based on fathead minnow ACR=15.34) with the most sensitive species in submitted acute freshwater fish studies, bluegill sunfish ( Lepomis macrochirus ).

2 In the latest Agency risk assessment th at looked at permethrin effects to a quatic species (US EPA 2008a), the most sensitive acute EC 50 value of 0.0212 μg a.i./L (Anderson et al. , 2005; ECOTOX Ref. # 90039) for amphipods ( Hyalella

azteca ). Upon further review, this study is determined to be supplemental information that is not suitable for quantitative purposes. The most sensitive acceptable freshwater aquatic i nvertebrate acute toxicity study is displayed here.

3 In the latest Agency risk assessment that looked at perm ethrin effects to aquatic speci es (US EPA 2008a), the chronic NOAEC for freshwater invertebrates was estimated to be 0.0 014 μg a.i./L using an acute-to-chronic ratio (based on fathead minnow ACR=15.34) with the most sensitive species in available acute freshwater invertebrate studies, the amphipod Hyalella azteca . Note that the empirical chronic NOAEC is similar to the most sensitive acute EC 50 in the previously submitted studies.

4 In the latest Agency risk assessment that looked at perm ethrin effects to aquatic speci es (US EPA 2008a), the chronic NOAEC for estuarine/marine fish was estimated to be 0.1434 μg a.i./L using an acute-to-chronic ratio (based on fathead minnow ACR=15.34) with the most sensitive species in submitted acute estuarine/marine fish studies, Atlantic silverside ( Menidia menidia ).

5 This mysid life cycle study did not evaluate the effects of permethrin exposure on reproduction due to poor control performance. Note that the empirical chronic NOAEC is similar to the most sensitive acute LC 50 in the available registrant-submitted studies. In the latest Agency risk assessment that looked at permethrin effects to aquatic species (US EPA 2008a), the chronic NOAEC for estuarin e/marine invertebrates was estimated to be 0.0012 μg a.i./L using an acuteto-chronic ratio (based on fathead minnow ACR=15.34) with the most sensitive species in submitted acute estuarine/marine invertebrate studies, stone crab ( Menippe mercenaria ).

Freshwater Fish

The acute toxicity studies availabl e to the Agency demonstrate that permethrin can be classified as very highly toxic to freshwater fish on an acute basis, with LC 50 values ranging from 0.79 to 72 μg a.i./L for a number of different species. The LC 50 values ranging from 0.79 to 17.0 μg a.i./L for permethrin TGAI, and from 2.3 to 72.0 μg a.i./L for formulated permethrin. Bluegill45 sunfish ( Lepomis macrochirus ) exhibited the most sensitive acute LC 50 value of 0.79 μg a.i./L for freshwater fish (MRID 00042128).

One acceptable life-cycle study on fathead minnows ( Pimephales promelas ) was available to the Agency to evaluate the effects of chronic exposur e to permethrin (95.7% a.i.) on freshwater fish (MRID 00110666). The study demonstrated that chroni c exposure to concentrations as low 0.41 μg a.i./L has the potential to cause reproductive t oxicity. A significant reduc tion in the number of surviving fry at 0.41 μg a.i./L relative to the c ontrols was observed (8% vs. 85-95% survival in controls). No other adverse effects were not ed on growth or number of eggs produced. Therefore, the NOAEC and LOAEC for this study are 0.30 μg a.i./L and 0.41 μg a.i./L, respectively.

In the latest Agency risk assessment that looke d at permethrin effects to aquatic species (US EPA 2008a), the chronic NOAEC for freshwater fish was estimated to be 0.0515 μg a.i./L using an acute-to-chronic ratio (based on fathead mi nnow ACR=15.34) with the most sensitive species in submitted acute freshwater fish studies, bluegill sunfish ( Lepomis macrochirus ).

Estuarine/Marine Fish

The acute toxicity studies availabl e to the Agency demonstrate that permethrin can be classified as highly toxic to very highly toxic to estuarine/marine fish, with LC 50 values ranging from 2.2 to >300 μg a.i./L. The studies also demonstrate that the technical grade act ive ingredient can be classified as very highly toxic, with LC 50 values ranging from 2.2 to 7.8 μg a.i./L. Formulated permethrin is classified as highly toxic to es tuarine/marine fish with a single reported LC 50 value of >300 μg a.i./L. The most sensitive acute LC 50 value in an estuarine/marine fish study was 2.2 μg a.i./L (MRID 40228401) for Atlantic silversides ( Menidia menidia ).

One early life-stage study with sheepshead minnows ( Cyprinodon variegatus ) was available to the Agency to evaluate the effects of chr onic exposure to permethrin (93% a.i.) on estuarine/marine fish (USEPA Gulf Br eeze 1983, MRID 41068007 [unreviewed]). The study demonstrated that chronic exposure to concentrat ions as low 22 μg a.i./L has the potential to cause reduced survival in hatched fish. No effect s were observed on weight, length or survival of hatched fish at 10 μg a.i./L. However, the chro nic NOAEC in this study is higher than the most sensitive acute LC 50 in submitted estuarine/marine fish studies. In the latest Agency risk assessment that looked at permethrin effects to aquatic species (US EPA 2008a), the chronic NOAEC for estuarine/marine fish was estimated to be 0.1434 μg a.i./L usin g an acute-to-chronic ratio (based on fathead minnow AC R=15.34) with the most sensitive species in submitted acute estuarine/marine fish studie s, Atlantic silverside ( Menidia menidia ).

Freshwater Invertebrates

The acute toxicity studies availabl e to the Agency demonstrate that permethrin can be classified as slightly toxic to very highly toxic to freshwater invertebrates, with EC 50 values ranging from46 0.039 to <25,000 μg a.i./L. Formulated permethrin is classified as slightly toxic to very highly toxic, with EC 50 values ranging from 0.76 to <25,000 μg a.i./L.

Evidence in open literature suggests that Hyalella azteca is among the most sensitive aquatic invertebrates to permethrin based on acute wa ter column tests (Weston and Lydy, 2010; Brander et al., 2009). For the 2008 Agency California red-legged frog and San Francisco Bay species risk assessment (USEPA 2008a), a study was identified in the open literature which reported a more sensitive EC 50 value (Anderson et al ., 2005; ECOTOX Ref. # 90039). This study was conducted to determine the toxicity of pe rmethrin to the baetid mayfly Procloeon sp. , the amphipod Hyalella azteca , and the midge Chironomus dilutus . The determined 48-hour ( Procloeon sp. ) and 96-hour ( H. azteca and C. dilutus ) EC 50 values for the mayfly, amphipod, and midge were 0.0896, 0.0212, and 10.45 μg a.i./L, respectively. Specifically, the estimated EC 50 value for H.

azteca is of interest because it is more sensitive than the most se nsitive toxicity value from the other studies available to the Agency. This study has been reviewed and the most sensitive acute EC 50 value of 0.0212 μg a.i./L (Anderson et al. , 2005; ECOTOX Ref. # 90039) for amphipods ( Hyalella azteca ). However, upon additional review, the study previously used for permethrin toxicity to Hyallela azteca is determined to be acceptable fo r supplemental (not quantitative) use in the upcoming Agency ecological risk assessm ent for permethrin. This decision is based on concerns with test substance stability during th e study and high solvent control mortality (the solvent used was at levels approximately 20 times higher than Agency guideline recommendations for aqua tic toxicity tests).

There are a total of two chronic exposure stud ies with technical-grad e permethrin involving freshwater invertebrates. These two guideline life-cycle studies with waterfleas ( Daphnia

magna ) report NOAEC values ranging from 0.039 to 0.28 μg a.i./L. The first study reported the NOAEC and LOAEC as 0.039 and 0.084 μg a.i./L, respectively, based on 14% and 4% reductions in the number of young produced pe r female and length, respectively (MRID 43745701). Decreased adult survival was also observed at 0.34 μg a.i. /L. In the second life cycle study, total production of young per adult and adu lt survival were decreased by 13% and 4%, respectively, at 0.56 μg a.i./L (EPA Belts ville TN 2420, 1979). The NOAEC was reported as 0.28 μg a.i./L. The available information indicate s that daphnids are not as sensitive as other freshwater invertebrates. Therefore, chronic eff ects to these more sensitive species will need to be addressed in the forthcoming risk assessment, either through the use of open literature data or through toxicity extrapolations (acute -chronic ratios using amphipod data).

In the latest Agency risk assessment that looke d at permethrin effects to aquatic species (US EPA 2008a), the chronic NOAEC for freshwater invertebrates wa s estimated to be 0.0014 μg a.i./L using an acute-to-chronic ratio (bas ed on fathead minnow ACR=15.34) with the most sensitive species in available acute fresh water invertebrate studies, the amphipod Hyalella

azteca . Note that the empirical chronic NOAEC is similar to the most sensitive acute EC 50 in the previously submitted studies.

No toxicity studies have been submitted to the Ag ency that examine the effects of permethrin to freshwater benthic organisms. Chronic sedime nt toxicity data for the freshwater midge Chironomus dilutus (Formerly Chironomus tentans ) were identified as an outstanding data requirement in the permethrin Reregistra tion Eligibility Document (US EPA 2009b). The47 registrant has submitted protocols for chronic sediment tests with both Chironomus dilutus (MRID 48035202) and the freshwater amphipod Hyalella azteca (no MRID assigned) and the Agency has provided protocol reviews (DPs 379360 and 382674).

Estuarine/Marine Invertebrates

The acute toxicity studies availabl e to the Agency demonstrate that permethrin can be classified as moderately toxic to very highly toxic to estuarine/marine invertebrates, with EC 50 values ranging from 0.018 to 6500 μg a.i./L. For bivalves, EC 50 values ranged from >407 to 6500 μg a.i./L (none of these tests were determined to be acceptable) and 0.018 to 7.6 μg a.i./L for the rest of the estuarine/marine invertebrates. The studies also demonstrate that both the technical grade active ingredient and formulat ed permethrin can be classified as moderately toxic to very highly toxic, with EC 50 values ranging from 0.018 to >1050 μg a.i./L and 0.51 to 6500 μg a.i./L, respectively. The most sensitive acute EC 50 value for estuarine/marine invertebrates is 0.018 μg a.i./L (MRID 40228401) for stone crabs ( Menippe mercenaria ).

Two estuarine/marine invertebrate chronic exposure studies with permethrin are available to the Agency. The first life-cycle study with mysids ( Americamysis bahia ) reports NOAEC and LOAEC values of 0.011 and 0.024 μg a.i./L, respec tively, based on a 20% increase in mortality at the LOAEC relative to the control (M RID 41315701). While no adverse effects on growth were noted based on adult body weight (length m easurements were not ta ken), the effects of chronic exposure to permethrin on reproduction of mysids could not be evaluated in this study due to significant study limitations ( i.e. , poor reproductive performance of controls). Therefore, the utility of this study for risk assessment purposes is severely limited. The other chronic permethrin study conducted with mysids was determ ined to be invalid because no raw data was reported to enable verification of results, stock solution mix-ups and excessive deaths related to the mysids jumping from the test containers (MRID 40102001).

This mysid life cycle study did not evaluate th e effects of permethrin exposure on reproduction due to poor control performance. Note that the empirical chronic NOAEC is similar to the most sensitive acute LC 50 in the available registrant-submitted studies. In the latest Agency risk assessment that looked at permethrin effects to aquatic species (US EPA 2008a), the chronic NOAEC for estuarine/marine invert ebrates was estimated to be 0.0012 μg a.i./L using an acuteto-chronic ratio (based on fathead minnow ACR=15.34) with the most sensitive species in submitted acute estuarine/marine invertebrate studies, stone crab ( Menippe mercenaria ).

No toxicity studies have been submitted to the Ag ency that examine the effects of permethrin to estuarine/marine benthic organisms. Chronic sediment toxicity data for Leptocheirus plumulosus were identified as an outstanding data requirement in the permethrin Reregistration Eligibility Document (US EPA 2009b). The regi strant has submitted a protocol for a chronic sediment test with Leptocheirus plumulosus (MRID 48035201) and the Agency has provided reviews (DPs 379360).

Aquatic-phase Amphibians48 Previously for the 2008 listed species assessmen t, a number of studies involving amphibian toxicity testing and permethrin were identified in the open litera ture for the previous ecological assessment for permethrin (US EPA 2008a). None of these studies provided estimates of toxicity that were ultimately used quantitatively in this risk assessment. However, they do provide some information regarding the hazard of permethrin to amphibians and will be used for characterization in the upcoming risk assessment.

Effects of degradates on aquatic organisms Various degradates were observe d in the laboratory studies ( e.g. m -PBA, m -PBAlc, and cis - and

trans -DCVA). These studies indicate that all of the identified degradates were the result of the rupture of the ester bond of the parent molecule. It has been believed that the resulting molecules are not as toxic as the parent because they presumably have lost the neurotoxic mode of action. Table 3.1c (above) shows the chemical structures of permethrin’s major degradation products.

Evaluation of the chemical struct ure of permethrin degradates s uggests little similarity to the active parent compound, and the cleavage of the ester linkage during degr adation of the parent structure is expected to result in a significantly de creased toxicity of those degradates relative to the parent. Limited data are available for the acute effects of DCVA on aquatic invertebrates. Acute 48-hour studies examining effects of DCVA on Daphnia magna resulted in an EC 50 = 25 mg a.i./L (MRID 00158556), which shows much lower toxicity to aquatic invertebrates than the parent compound permethrin ( Daphnia magna 48-hour EC 50 s range from 0.04 to 9.9 μg a.i./L for the parent compound permethrin; MRIDs 00043736, 00110662, 00043736, 40098001, 00110663, 00110662, 00042139, 43740602 and 42584002). Based on these lines of evidence, this assessment focuses only on the parent, cis- and trans -permethrin.

These conclusions are in agreement with EPA’s Health Effects Division’s (HED) approach of considering only the parent as the residue of concern for purpos es of tolerance expression and risk assessment (HED chapter of the Reregist ration Eligibility Decisi on Document (RED) for permethrin, 6 th revision dated April 1 st 2009; DP Barcode D357566, see Appendix I). At this time, the degradates will not be considered stressors of concern in the forthcoming environmental fate and ecological risk assessment.

Temperature-based effects on permet hrin toxicity to aquatic organisms The effect of temperature on permethr in toxicity is discussed by Weston et al. (2009a). Sediment toxicity tests were performed at va rious temperatures (13, 18, 23 and 28oC). The 10- day LC 50 s to Hyalella azteca were determined in lab tests conducted on four pyrethroids ( lambda -cyhalothrin, permethrin, bife nthrin and esfenvalerate). The toxicity approximately doubled when the temperature was decreased from 23 to 18oC, and approximately tripled when the temperature was further decreased to 13oC. This effect has implications for aquatic organisms that inhabit water bodies in colder climates (Weston et al. 2011). The potential for temperaturemediated changes in pyrethroid toxicity will be examined in the upcoming risk assessment for permethrin.49 Plants

Table 4.3. Permethrin Toxicity Profile for Plant Species

Species % A.I. Toxicity Endpoint

μ g a.i. /L Study Classification MRID/

Reference

Freshwater Non-vascular Plants

Marine algae Selenastrum

costatum Not reported 1 EC 50 96 hr : 68 and 72 μg a.i./L

Yield (Cell count) EC 50 96 hr: 68 μg a.i./L NOAEC: Not reported

Absorbance EC 50 96 hr: 72 μg a.i./L NOAEC: Not reported Supplemental ECOTOX

Ref #5297 (Walsh and Alexander, 1980)

Marine algae Selenastrum

costatum 93 EC 50 96 hr : 92 μg a.i./L NOAEC: Not reported Supplemental 40228401

Blue-green algae, Anabaena inequalis 14.7 Yield (Cell density) EC 50 : 1.6 mg a.i./L NOAEC: Not reported

Growth rate EC 50 : 5.0 mg a.i./L NOAEC: Not reported

Photosynthesis EC 50 : >100 mg a.i./L NOAEC: Not reported

Acetylene reduction EC 50 : >100 mg a.i./L NOAEC: Not reported Supplemental ECOTOX

Ref #4684 (Stratton et al

., 1980)

No studies evaluating the toxicity of permethrin to terrestrial plants have been submitted to the Agency.

Only one study examining the toxicity of permethr in to non-vascular aquatic plants is available to the Agency (MRID 40228401). This study involvi ng technical permethrin (93% a.i.) and the marine diatom ( Skeletonema costatum ) reports an EC 50 value of 92 μg a.i./L However, no NOAEL, raw data, or additional information were reported.50 For the 2008 California red-legged frog and San Francisco Bay species (USEPA 2008a) and the 2010 Valley Elderberry Longhorn Beetle ( Desmocerus californicus dimorphus ) permethrin assessments (USEPA 2010), only two other studies establishing EC 50 values for non-vascular plants were identified in the open literature. The first (Stratton et al., 1980; ECOTOX Ref # 4684) laboratory toxicity assay was conducted to determine the effects of permethrin on the growth (yield and rate), 14 CO 2 uptake, and acetylene reduction of the blue-green alga, Anabaena inequalis . The study determined the EC 50 of permethrin towards growth yield, growth rate, photosynthesis (uptake of 14 CO 2 and NaH 14 CO 3 ), and acetylene reduction to be 1.6, 5.0, >100 and >100 mg a.i./L, respectively. However, no NOAEL or raw data were reported.

The second open literature st udy (Walsh and Alexander, 1980; ECOTOX Ref # 5297) was conducted to evaluate methodologies of marine al gal bioassays and to determine the effects of permethrin on the marine alga, Skeletonema costatum . The 96-hour static toxicity test yielded growth EC 50 values of 68 and 72 μg a.i./L, based on cell counts and absorbance, respectively. However, no NOAEL or raw data were reported.

No acceptable data from registrant-submitted studie s or the open literatu re on the toxicity of permethrin to aquatic vascular plants were av ailable to the Agency for this assessment.

ECOTOX Available open literature will be used to evaluate the potential direct effects of permethrin to the terrestrial receptors iden tified in this section. Th is includes toxicity data on the technical grade active ingredient, and when available, formulated products ( e.g. “Six-Pack” studies).

The open literature studies will be identified through EPA’s ECOTOX database ( http://cfpub.epa.gov/ecotox/ ), which employs a literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants , and wildlife. The evalua tion of data can also provide insight into the direct and indirect eff ects of permethrin on biotic communities from loss of species that are sensitive to the chemical and from changes in structure and functional characteristics of the affected communities. Open lit erature toxicity data fo r other ‘target’ insect species (not including bees, but terflies, beetles, and non-insect invertebrates including soil arthropods and worms), which include efficacy studi es, are not currently considered in deriving the most sensitive endpoint for terrestrial ins ects. Efficacy studies do not typically provide endpoint values that are useful for risk assessment ( e.g. , NOAEC, EC 50 , etc.), but rather are intended to identify a dose that maximizes a particular effect ( e.g. , EC 100 ). Therefore, efficacy data and non-efficacy toxicological target insect data will not be included in the ECOTOX open literature search.

4.2. Incident Database Review

A review of the Ecological Incident Informa tion System (EIIS, v. 2.1) and Aggregate Incident databases for ecological incidents involving perm ethrin was completed on January 4, 2011. This database consists of exposure incident repor ts submitted to the EPA from 1994 to present. A51 search for incidents involvi ng permethrin was also conducted in the American Bird Conservancy’s Avian Incident Monitoring System (AIMS).

The reports are listed in order of certainty, from highly probable to unrelated. Incidents listed in EIIS are categorized by the likelihoo d that a particular pesticide is associated with that particular incident. These classifications in clude highly probable, probable, possible, unlikely or unrelated. “Highly probable” incidents usually require carcass residues or cl ear circumstances regarding the exposure. “Probable” incidents include those where residue info rmation was not available or circumstances were less clear than those for “hig hly probable”. “Possible” incidents occur when multiple chemicals may have been involved and the contribution of an individual chemical is not obvious. An “unlikely” incident classification is given when a given chemical is considered nontoxic to the type of organism involved or the chemical was analyzed and not detected in samples. The “unrelated” category is used for in cidents confirmed not to involve pesticides. No unrelated incidents were listed for permethrin.

The number of reports listed in the EIIS database is believed to be only a small fraction of the total incidents involving organism al mortality and damage caused by pesticides. Few resources are assigned to incident re porting. Reporting by states is only voluntary, and individuals discovering incidents may not be informed on the procedure of repor ting these occurrences. Additionally, much of the database is generated from registrant-submitted incident reports. In addition, incident reports for non-target organisms typically provide information only on mortality events and plant damage incidents. Ex cept for phytotoxic effects in terrestrial plants, sublethal effects for organisms such as reduced growth or impaired reproduction are rarely reported. Because of these logistical difficulties, EIIS is most likely a minimal representation of all pesticide-related ecological incidents.

Registrants are legally required to provide detailed reports of only “major” ecological incidents involving pesticides, while “minor” incident s are reported aggregately. Based on 40 CFR §159.184, an ecological incident is considered “maj or” and must be submitted to the Agency by the registrant if any of th e following criteria are met:

Fish or wildlife: (A) Involves any incident caused by a pe sticide currently in Formal Review 24 for ecological concerns. (B) Fish: Affected 1,000 or more individua ls of a schooling species or 50 or more individuals of a non-schooling species. (C) Birds: Affected 200 or more individuals of a flocking species, or 50 or more individuals of a songbird species, or 5 or mo re individuals of a predatory species. (D) Mammals, reptiles, amphibians: Af fected 50 or more individuals of a relatively common or herding species or 5 or more individuals of a rare or solitary species.

24 Formal Review means Special Review, Re buttable Presumption Against Registration (RPAR), FIFRA section 6(c) suspension proc eeding, or FIFRA section 6(b) cancellation proceeding, whether completed or not.52 (E) Involves effects to, or illegal pesticide treatment (misuse) of a substantial tract of habitat (greater than or equal to 10 acres , terrestrial or aquatic). Plants : (A) The effect is alleged to have occurre d on more than 45 percent of the acreage exposed to the pesticide.

All other incidents are consider ed “minor”. All ecological in cidents considered “minor” only need to be aggregately reported as quarterly coun ts of incidents by the re gistrant(s). Ecological incidents reported in aggregate re ports include those cate gorized as ‘minor fi sh and wildlife’ (WB), ‘minor plant’ (P-B), and ‘other non-target ’ (ONT) incidents. ‘Oth er non-target’ incidents include reports of adverse e ffects to insects and other terrestrial invertebrates. For permethrin, registrants have reported 14 minor fish and wi ldlife incidents, 149 minor plant incidents, and 4 other non-target incidents. Unless additional information on these aggregated incidents become available, they will be assumed to be repr esentative of registered uses of permethrin in the risk assessment.

The EIIS database contained 41 incidents in volving permethrin. The reports included 26 aquatic animal incidents, 8 terrestrial anim al permethrin-related incidents and 8 plant incidents (one terrestrial incident involved both plants and animals).

The AIMS database contains no avi an incidents involving permethrin.

A summary of ecological incident s involving permethrin included in the EIIS database are listed in Appendix B

.
Aquatic Incidents The majority of ecological incidents involving permethrin occurred in aquatic environments. Twenty-six aquatic incidents caused by permethr in have been reported to the EPA since 1994. Of these incidents, nine are li sted as highly probable, ten as probable, and seven under possible. Twenty-three incidents affected fish species, and the other three repo rts involved crayfish. Approximately half (thirteen) of the incidents re sulted from registered use of permethrin. Many of these incidents originate with permethrin application to residenc es or other buildings, followed by permethrin runoff into nearby water bodies.

One case listed as a possible permethrin-relate d event involved frogs. A mosquito control employee of the Maryland Department of Agricultu re sprayed permethrin within 100 feet of a pond, and one day later many frogs, fish and crayfi sh were found dead. Although the applicator’s certificate was suspended, permethrin is implicated as only a possible cause because no tissues or water samples were analyzed.

Plant Incidents Seven permethrin incident reports were recorded for terrestrial plant species. All incidents were only listed as possible or unlikely. Two reports involved registered use. The first registered-use incident involved both permethrin and piperony l butoxide, and the plant damage could not be solely attributed to either chemical. In the sec ond registered-use incide nt, many pesticides were involved and imazethapyr was suspected to be the cause of any plant injuries, not permethrin.53 Terrestrial Incidents Six permethrin incidents involving terrestrial animals exist in th e EIIS database. Two incidents were listed as highly probable, and four as possible. One of the highly probable incidents resulted from registered use. A municipality was sprayed with permethrin, and hundreds to thousands of dead butterflies were found by resi dents of the area shortly after application. Species listed in these reports included bee, monarch butterfly, ot her unknown butterflies, parakeet, dog, unknown birds, unknown trees and ornamental plants. .

In the forthcoming ecological risk assessment, these incidents will be further evaluated to determine if they represent current patterns of use for permethrin. Examples of additional considerations are mitigation ( e.g ., reduced application rates), product cancellations, and changes in use patterns that have occurr ed since the date of the reporte d incidents. In addition, any known incidents that occur between the time the PF document is issued and the final risk assessment will be included in the risk assessment.

4.3. Ecosystems Potentially at Risk

Permethrin may be applied on a variety of food/f eed crops, including (but not limited to), alfalfa, nut trees, corn, leafy vegetables, stone fru its, pome fruits, fruiting vegetables, cucurbit vegetables, cole crops, onion and soybean. In addition, it may be used on numerous non-food sites ( e.g. conifers, forest trees, ornamentals, golf courses, and ornamental lawns and turf, rangeland, as an adulticide and for wood protecti on). Thus, the ecosystems at risk may be extensive in scope, and as a re sult it may not be possible to id entify specific ecosystems during the development of a baseline risk assessment. In general terms, terrestrial ecosystems potentially at risk due to th e use of permethrin, could include the treated field and areas immediately adjacent to the treated field that may receive drift or runoff. Areas adjacent to the treated field could include cultiv ated fields, fencerows and hedgero ws, meadows, fallow fields or grasslands, woodlands, riparian habitats and other uncultivated areas. Due to the potential persistence of permethri n, it is expected to drift and/ or r unoff due to application to food crops and certain non-crop sites, resulting in possi ble exposure to aquatic ecosystems. Aquatic ecosystems potentially at risk due to the use of permethrin include water bodies adjacent to, or down stream from the treated field and might include impounded bodies such as ponds, lakes and reservoirs, or flowing waterways such as streams or rivers. For uses in coastal areas, aquatic habitat also includes marine ecosy stems, such as estuaries.

5. Assessment Endpoints

Assessment endpoints are defined as “explicit expressions of the actual envir onmental value that is to be protected.” Defining an assessment e ndpoint involves two steps: 1) identifying the valued attributes of th e environment that are considered to be at risk; and 2) operationally defining the assessment endpoint in terms of an ecological entity ( i.e. , a community of fish and aquatic invertebrates) and its attributes ( i.e. , survival and reproduction). Therefore, selection of the assessment endpoints is ba sed on valued entities ( i.e. , ecological receptors), the ecosystems54 potentially at risk, the migration pathways of pesticides, and the routes by which ecological receptors are exposed to pesticide-related cont amination. The selection of clearly defined assessment endpoints is important because they provide direction and bou ndaries in the risk assessment for addressing risk management issues of concern. Changes to assessment endpoints are typically estimated from the available toxici ty studies, which are used as the measures of effects to characterize potential ecological risks associated with exposure to pesticides, such as permethrin.

To estimate exposure concentrations , the ecological risk assessment considers applications at the maximum application rate to fields that have vu lnerable soils. The most sensitive toxicity endpoints are used from surrogate test species to estimate treatment-re lated direct effects on acute mortality and chronic reproductive, growth and survival assessment endpoints. Toxicity tests are intended to determine e ffects of pesticide exposure on bi rds, mammals, fish, terrestrial and aquatic invertebrates, and plants. These tests include short-term acute, sub-acute, and reproduction studies and are typically arranged in a hier archical or tiered system that progresses from basic laboratory tests to appl ied field studies. The toxicity studies are used to evaluate the potential of a pesticide to cause adverse effects, to determine wh ether further testing is required, and to determine the need for precautionary labe l statements to minimize the potential adverse effects to non-target animals and plants.

An open literature search will be conducted to dete rmine any relevant endpoints. The search will focus on survival, growth and reproductive eff ects for aquatic and terrestrial effects of permethrin. More sensitive endpoints from acceptabl e open literature studies will be included in the ecological risk assessment.

6. Conceptual Model

For a pesticide to pose an ecological risk, it mu st reach ecological receptors in biologically significant concentrations. An exposure pathway is the means by which a pesticide moves in the environment from a source to an ecological recepto r. For an ecological pathway to be complete, it must have a source, a release mechanism, an environmental transport medium, a point of exposure for ecological receptors, an d a feasible route of exposure.

A conceptual model provides a written descriptio n and visual representation of the predicted relationships between permethrin, potential routes of exposure, and the predicted effects for the assessment endpoint. A conceptual model consists of two major components: risk hypothesis and a conceptual diagram (USEPA, 1998).

6.1. Risk Hypothesis

Risk hypotheses are specific assumptions about potential adverse effects ( i.e. , changes in assessment endpoints) and may be based on theory and logic, empirical data, mathematical models, or probability models (USEPA 1998). For th is assessment, the risk is stressor-initiated, where the stressor is the releas e of permethrin into the envi ronment. The following risk hypotheses are presumed for this screening-level assessment:55 Permethrin, when used outdoors in accordance w ith registered labels, will likely lead to off-site movement of the compound via agricu ltural and urban runoff, spray drift, and eroded soil leading to exposure of nontarget plants and animals Based on information on the environmental fate, mode of action, dire ct toxicity and potential indirect effects, EFED assumes that registered uses of perm ethrin have the potential to cause reduced survival, growth, and reproduction to non-target terrestrial and/ or aquatic animals and plants.

Permethrin, when used indoors for numerous uses, including pre- treated clothing, pet shampoos, prescribed or over-the-counter pr oducts, etc., in accordance with current labels, may result in off-site movement of the compound via wash-off into surface waters via drains and municipal wast ewater treatment plants, lead ing to exposure of nontarget aquatic plants and animals. This potentia l exposure pathway may result in adverse effects upon the survival, growth, and/or re production of non-target aquatic animals and plants.

Permethrin, when used for the treatment of cattle (and certain other animals), in accordance with current labels, may result in off-site movemen t of the compound via wash-off of cattle and calves into surfa ce waters, leading to exposure of nontarget aquatic plants and animals. This potentia l exposure pathway may result in adverse effects upon the survival, growth, and/or re production of non-target aquatic animals and plants.

The conceptual model is a generic graphic depi ction of the risk hypothesis. It includes the potential pesticide or stressor (permethrin and pos sible metabolites, as well as synergists), the source of the pesticide and/or transport pathways, exposure me dia, exposure point, biological receptor types, and attribute changes.

6.2. Conceptual Diagram

The conceptual site model is a generic graphic de piction of the risk hypothesis, and assumes that the insecticide permethrin, which is a Type I synthetic pyrethroid, having multiple outdoor agricultural and non-agricu ltural uses, is capable of affecting aquatic a nd terrestrial animals provided that environmental concen trations are sufficiently elevated as a result of proposed label uses. Based on an examination of the physicoche mical properties of permethrin, the fate and disposition in the environment, and mode of application, a concep tual model was developed that represents the possible relati onships between the stressors, ecological recept ors, and the assessment endpoints. Through a preliminary iterat ive process of examining available data, the conceptual model ( i.e ., the representation of the risk hypothe sis) may be refined to reflect the likely exposure pathways and the organisms that are most relevant and applicable to this assessment ( Figures 6.1a and 6.1b ). They include the potential pesticide or stressor (permethrin, but the presence of toxicologically important metabolites and/ or s ynergists cannot be ruled out), the sources and/ or transport pathways, exposure media and expos ure points, biological receptor types and attribute changes.56 In order for a chemical to pose an ecologica l risk, it must reach ecological receptors in biologically significant c oncentrations. An exposure pathway is the means by which a pesticide moves in the environment from a source to an ecological receptor. For an ecological exposure pathway to be complete, it must have a source, a release mechanism, an environmental transport medium, a point of exposure for ecological recep tors, and a feasible route of exposure. In addition, the potential mechanisms of degradation/ transformation ( i.e. , which degradation/ transformation products may form in the environm ent, in which media, and how much) must be understood, especially if for the chemical, its metabolit es/ transformation products are of greater toxicological concern than the parent com pound. The assessment of ecological exposure pathways, therefore, includes an examination of the source and pot ential migration pathways for constituents, and the determination of potential exposure routes.

Under the possible uses of permethrin, the sour ces and mechanisms of release of the compounds are from ground or aerial spray or ULV applications . Note that this conceptual model considers agricultural applications as well as certain non-ag ricultural applications. Surface runoff from the areas of application is assumed to depend on f actors such as topography, irrigation, and rainfall events. Direct deposition may result in contam ination of food items that may be consumed by terrestrial organisms. Spray dr ift results in contaminated adj acent areas, including bodies of water. Leaching to groundwater is not consider ed an important source because permethrin, like many other pyrethroids, shows low mobility in a vari ety of soils. Permethrin appear to have a low potential for volatilization, wi th a low vapor pressure and Henr y’s Law Constants. Further, the hydroxyl radical reaction half-lif e for permethrin is ~0.5 days (EPI Suite v.4.0 estimate). The short (atmospheric) half-life, the low vapor pressure (~10 -8 mmHg) and relatively low Henry’s Law constant (~10 -6 atm/m 3 -mol), and its binding capacity, suggest that the potential for atmospheric transport for permethrin is relatively low and that this source of the chemical is of low importance, compared to spray drift, runo ff and/ or direct contact after application.

For aquatic receptors, the major point of expos ure is through direct contact with the water column, sediment, and pore water (gill/ integumen t) contaminated with spray drift (from spray application) and/or runoff and flow ( e.g. , piped storm drains) from treat ed areas. Indirect effects to aquatic organisms (both fish and aquatic i nvertebrates) can also occur through impact to various food chains. The representative aquatic receptors are certain fres hwater and estuarine/ marine fish, invertebrates, and, in certain cases, aquatic plants. The major point of exposure for terrestrial animals is consumption of food contaminated with residue s such as grass, foliage, and small insects. For plants, the point of expos ure is direct contact or root uptake. The representative terrestrial receptors are mammals , birds and terrestrial plants. The attribute changes used to assess risk to terrestri al receptors depend on the type of test ( e.g. , reduced survival, growth, or reproduction for animals a nd seedling emergence and vegetative vigor for plants). It should be noted, that these species do not cover all th e possible species in the animal and plant kingdoms; certain taxa ar e considered as surrogates for other taxa. For example, fish are considered surrogates for aquatic phase amphibians.

This conceptual model also shows details about biomagnification for a chemical (see piscivorous birds and mammals in Fig. 6.1b ). It was established earlier in this document that permethrin may have some potential to bioa ccumulate/ bioconcentrate. Th e reported value of log octanol/57 water partition coefficient of 6.1 (K OW = 1.3 x 10 6 ) suggests that permethrin has the potential to bioaccumulate in aquatic organisms, assuming that chemical metabolism is negligible. However, the measured bioconcentration factor in fish ( Table 3.5 ) is much lower than that expected based
on K OW alone, which suggests that permethrin metabol ism by fish is substantial. However, there appears to be some potential for bioaccumulation/ bioconcentration in aquatic organisms, and biomagnification in te rrestrial organisms.

Permethrin shows a very low solubility, a very high K OW and also high K OC s. These properties suggest that the chemicals partit ion with the sediments, and with organic matter, suspended in the water bodies. Permethrin is likely to concen trate in the sediments, es pecially after repeated exposures (applications), where it could persist. Such sedime nts could serve as repositories of the chemical for extended periods of time and c ould potentially be toxic to sediment dwelling organisms, affecting the food chain. These issues will also be assessed in the risk assessment for permethrin.

Figure 6.1a. Aquatic conceptual model de picting stressors, exposure pathways, and potential effects to aquatic organisms from the use of permethrin on agricultural and certain non-agricultural sites

1 Includes flow across vegetation and vegetated drainage systems ( e.g. , swales) and flow across ** Route of exposure includes only ingesti on of fish and aquatic invertebrates. 

### Stressor

Source

Receptors

Attribute Change Permethrin applied to agricultural or non-agricultural use site

Spra y drif t

Aquatic animals Invertebrates Vertebrates **Piscivorous mammals and birds

Individual organisms Reduced survival (2) Reduced growth Reduced reproduction Food chain Reduction in algae and vascular plants Reduction in prey Modification of PCEs related to prey Habitat integrity Reduction in primary productivity Reduced cover Community change Modification of PCEs related to habitat Surface water/ S edimen t Runoff

Aquatic Animals Invertebrates Vertebrates 

### Exposure Media

Uptake/gills or integument

In g estion Ingestion Atmospheric transport

Wet/dry deposition Soil Leaching to Groundwater

Uptake/gills or integument

Aquatic Plants Non-vascular Vascular Uptake/cell, roots, leaves Riparian plants terrestrial
exposure pathways; see

Figure 6.1b Impervious Surfaces

Flow ( 1 )58 impervious surfaces and through impervious (piped) storm drains.

2 Immobilization is considered equivalent to mort ality in toxicity tests for aquatic invertebrates.

Dotted lines indicate exposure pathways that ha ve a low likelihood of c ontributing to ecological risk.

Figure 6.1b. Terrestrial conceptual model de picting stressors, exposure pathways, and potential effects to terrestria l organisms from the use of pe rmethrin on agricultural and certain non-agricultural sites

Dotted lines indicate exposure pathways that ha ve a low likelihood of c ontributing to ecological risk. *See Figure 6.1c for drinking water and inhalation exposure pathways for terrestrial vertebrates and ingestion of residues in de w by terrestrial invertebrates.

Drinking water, inhalation and dermal exposure pathways to terrestrial species

Drinking water The S creening I mbibition P rogram (SIP v.1.0, Released June 15, 2010) was used to calculate an

Stressor

Source

Attribute Change Permethrin applied to agricultural or non-agricultural use sites

Direct application Spray drift

Terrestrial vertebrates* Terrestrial Invertebrates*

Individual organisms Reduced survival Reduced growth Reduced reproduction Food chain Reduction in prey and food Modification of PCEs related to prey availability Habitat integrity Reduction in primary productivity Reduced cover Community change Modification of PCEs related to habitat Terrestrial plants grasses/ forbs, fruit, seeds (trees, shrubs) Runoff

Terrestrial vertebrates* Exposure Media & Receptors Soil

Ingestion Ingestion Ingestion Dermal uptake/Ingestion Atmospheric transport

Root uptake/contact
Wet/dry deposition

Ingestion Leaching to Groundwater Irrigation

water59 upper bound estimate of exposure using permet hrin’s solubility (0.0055 mg/L; Laskowski, 2002), the most sensitive acute and ch ronic avian toxicity endpoints (LD 50 > 2000 mg ai/kg bw and NOAEC = 125 mg ai/kg diet, respectively) and the most sensitive acute and chronic mammalian toxicity endpoints (LD 50 = 340.5 mg/kg bw; NOAEL = 4.9 mg ai/kg bw/day, respectively). Drinking water exposure alone was not de termined to be a potential pathway of concern for avian or mammalian species on an acute or chronic basis.

Although drinking water exposure alone does not appear to be of concern, this does not take into account that when aggregated with other exposure pathways (dietary food sources, dermal, inhalation) drinking water may c ontribute to a total exposure that has a potential for effects on non-target animals and should be explored fu rther. Because there is a high degree of conservatism in the SIP 1.0 exposure estimate, there is limited expectation that use scenarios not triggering a SIP 1.0 concern would contribute significantly to a ggregate risks from water plus diet when a refined water exposure model is in corporated in the actual quantitative risk assessment. Detailed information about SIP v.1.0, as well as the tool, can be found on the EPA’s website at http://www.epa.gov/pesticides/s cience/models_pg.htm#terrestrial

.

Inhalation S creening T ool for I nhalation R isk v.1.0 (STIR) was used to pr ovide an upper bound estimate of permethrin exposure of birds and mammals to pe sticides through inhalation of spray drift or vapor. It also provides an estimate of avian inhala tion toxicity in the absence of such data based on available acute inhalation and oral mammalian toxicity endpoint s as well as acute avian oral toxicity endpoints. The upper bound exposure estimate requires a number of input parameters including the vapor pressure and molecular weight for the vapor-phase pesticide; additionally it requires the application rate and method of application ( i.e. , ground or aerial) for spray drift. The toxicity aspect of the tool requires an avian acute oral LD 50 value, the chemical specific avian allometric scaling factor to ad just toxicity based on body weight for the chemical (if available), the weight of the tested bird, a rat acute oral LD 50 value, a rat acute inhalation LC 50 value, the duration of the rat inhalation study, and the weight of the tested ra t. This tool was designed for use in the Problem Formulation phase of the ecol ogical risk assessment pr ocess to quantitatively evaluate the need for further an alysis of inhalation as a potentia l pathway of concern for birds and mammals. Risk quotients (RQs) for inhalation exposure are not derived, and this tool will not be used to make risk determinations. Inst ead, the tool compares the ratio of exposure and toxicity to a threshold of 0.1, similar to the Agency’s LOC for listed terrestrial animals, and determines whether inhalation from spray drift or vapor phase pesticide alone may be a concern for mammals and/or birds.

The model tool is also available online on the O PP models web page at the following address: ( http://www.epa.gov/pesticides/s cience/models_pg.htm#terrestrial ).

STIR could not be utilized for permethrin due to the absence of acute mammalian inhalation toxicity data (USEPA, 2009a). However, inhalation exposure alone was not determined to be a potential pathway of concern for avian or mammalian species, based upon permethrin’s low vapor pressure (1.48 x 10 -8 mm Hg) and low acute avian toxicity (LD 50 > 2000 mg ai/kg bw) and acute mammalian toxicity (LD 50 = 340.5 mg/kg bw).60 Dermal Exposure Potential exists for permethrin dermal exposure to terrestrial wildlife. At the present time, the Agency does not have a method to quantify le vels of dermal exposure from chemical applications, but is actively working on a screenin g tool to account for this route of exposure.

Figure 6.1c. Terrestrial conceptual model depicting stressors, drinking water and inhalation exposure pathways, and potential eff ects to terrestrial orga nisms from the use of permethrin on agricultural and certain non-agricultural sites

Dotted lines indicate exposure pathways that ha ve a low likelihood of c ontributing to ecological risk.

Down-the-Drain Exposure The conceptual model for potential risks of perm ethrin to aquatic organisms due to various indoor uses of the chemical that could poten tially end up in a “dra in” is depicted in Fig. 6.2 . The stressor is the chemical of concern, permethri n. It is noted that th e transport pathway is wastewater flow, the exposure media is the trea tment facility and the e xposure point or route,61 receptor, and attribute changes for aquatic orga nisms are similar to the conceptual model for agricultural applications.

Figure 6.2. Conceptual model fo r potential risks of permethr in to aquatic organisms for various indoor uses of the chemical that could potentially end up in the “drain.”

The conceptual model for potential risks of permet hrin to terrestrial and aquatic organisms as a result of the treatment on cattl e or calves is depicted in Fig. 6.3 . The stressor is the chemical of concern, permethrin, and potentially interactions ca used by applications with the synergist PBO. The organisms that could be expected to be aff ected are terrestrial plan ts, aquatic plants and aquatic animals. It is noted that the potenti al transport pathway, the exposure media and the exposure point or route, receptor, and attribut e changes for plant and aquatic organisms are similar to the conceptual model for agricultural applications Fig. 6.1a

.

Stressor Permethrin applications that could potentially end up “downthe-drain”

Source/ Transport
Pathwa y s Wastewater flow

Source/ Exposure Media Treatment facility discharges into surface
waters

Exposure
Route Gill/ Integument Uptake

Rece p tors

Attribute Changes Aquatic Invertebrates, Vertebrates

Individual Vertebrates and

Invertebrates

Reduced survival or Plant Population Reduced population th A quatic Plants Uptake/ Adsorption62 Figure 6.3: Conceptual model fo r potential risks of permethrin to aquatic organisms as a result of the treatment on cattle or calves.

7. Analysis Plan

In order to address the risk hypot hesis, the potential for adverse effects on the environment is estimated. Usage, environmental fate and transp ort, and ecological effects of permethrin are characterized and integrated to assess the risks. This is accomplished using a risk quotient (ratio of exposure concentration to eff ects concentration) approach. A lthough risk is often defined as the likelihood and magnitude of adverse ecological effects, the risk quotient-based approach does not provide a quantitative estima te of likelihood and/ or magnitude of an adverse effect. However, as outlined in the Overview Docume nt (USEPA 2004), the likelihood of effects to individual organisms from par ticular uses of a chemical is estimated using the probit doseresponse slope and either the level of concern (d iscussed below) or the actual calculated risk quotient value.

This analysis plan will be re visited and may be revised dependi ng on the data available in the

Stressor Permethrin and PBO Used as for theTreatment of Cattle and Other Animals (Immersion in Surface Water Body or Washoff Transported N earby or to Surface Waters)

Source/ Transport
Pathwa y s Surface waters

Source/ Exposure Media Riparian/ Wetland Foliage/Soil Receiving Water Body/ Sediment

Exposure
Route Direct Contact/ Root Uptake Gill/ Integument

Uptake

Rece p tors

Attribute Changes Aquatic Invertebrates,

Vertebrates Wetland/ Riparian

Plants

Individual Plants Reduced survival, growth, or reproduction Individual Vertebrates and Invertebrates Reduced survival or reproduction Plant Population Reduced population

growth Aquatic Plants Uptake/ Adsorption63 open literature and the information submitted by th e public or the registrant in response to the opening of the Registration Review docket.

7.1. Stressors of Concern

The focus of this assessment is on the parent material, permethrin. However, the Agency will review open literature to identify degradat e(s) of potential toxicological concern ( e.g. , cis - and

trans -DCVA, m -PBA and m -PBalc). Also, risk resulting fr om use of permethrin with the synergist PBO will be assessed for cattle treatments.

Toxicity data for environmental mixtures of pe rmethrin with other pesticides (those mixtures occurring in the environment following application), if available, may be presented as part of the ecological risk assessment. Permethrin may be applied in tank mixtures with other products approved for use on registered crops . It is expected that the t oxic effect of permethrin, in combination with other pesticides used in the en vironment, is likely to be a function of many factors including, but not necessa rily limited to (1) the exposed species, (2) the co-contaminants in the mixture, (3) the ratio of permethrin and co-contaminant concentrations, (4) differences in the pattern and duration of exposure among contamin ants, and (5) the differential effects of other physical/ chemical characteristic s of the receiving waters ( e.g. organic matter present in sediment and suspended water). A discussion of implicat ions of the available pesticide mixture effects data on the confidence of risk asse ssment conclusions will be addre ssed in the risk description of the final ecological assessment.

7.2. Measures of Exposure

In order to estimate risks of permethrin exposur es in aquatic and terrestrial environments, all exposure modeling and resulting risk conclusion s will be made based on maximum application rates for the current use patterns. Available aquati c monitoring data, from sources such as the US Geological Survey and the California Stormwater Quality Association, will also be considered when describing potential environmenta l exposure to non-ta rget organisms.

Measures of exposure are based on aquatic and terrestrial models that predict estimated environmental exposure concentrations (EEC s) of permethrin using maximum labeled application rates and methods, as well as any m itigation measures specif ically indicated on the label. The models used to pr edict aquatic EECs are the Pesticid e Root Zone Model coupled with the Exposure Analysis Model System (PRZM/E XAMS). Also, to estimate aquatic exposure related to releases of permethrin from domestic wastewater treatment plants, the Exposure and Fate Assessment Screening Tool’s (E-FAST2) down-the-drain module will be used. For the treatment of cattle, measures of exposure will be calculations assuming di rect applications to water considering living habits of cattle livestock. The model used to predict terrestrial exposure is T-REX. The model used to derive EECs relevant to terrestrial and wetland plants is TerrPlant. The potential for bioaccumulation for the chemical is assessed using the KABAM model, as well the results from bioconcentr ation in fish studies ( e.g. the bioconcentration factors). These models are parameterized using relevant reviewed registrant-submitted environmental fate and transport data.64 PRZM (v.3.12.2, May 2005) and EXAMS (v.2.98.4.6, Ap ril 2005) are screening simulation models coupled with the input shell PE5.pl (August, 2007) to gene rate daily exposures and 1-in10 year EECs of permethrin, that may occur from spray drift and runoff to surface water bodies adjacent to application sites. PRZM simu lates pesticide application, movement and transformation on an agricultural field and the re sultant pesticide loadings to a receiving water body via runoff, erosion and spray drift. The E XAMS model simulates the fate of the pesticide and resulting concentrations in the water body. The standard scenario used for ecological pesticide assessments assumes application to a 10 -hectare agricultural field that drains into an adjacent 1-hectare water body that is 2 meters de ep (20,000 cubic meters volume) with no outlet. PRZM/ EXAMS is used to estimate screening-leve l exposure of aquatic organisms to permethrin and/ or its transformation products, should they be of concern. The measure of exposure for aquatic species is the 1-in-10 year return peak or rolling mean concentration. The 1-in-10 year peak is used for estimating acute exposures of di rect effects to aquatic organisms. The 1-in-10- year 60-day mean is used for assessing chronic exposure to fish and aquatic-phase amphibians. The 1-in-10-year 21-day mean is used for a ssessing aquatic invertebrate chronic exposure.

At the present time, EFED considers the use of the impervious scenar io (a PRZM modeling scenario) as the most suitable available modeling approach for impervious runoff. The PRZM impervious scenario may be used in the ti er 2 coupled aquatic models PRZM/EXAMS along with the residential or other suitable scenario such as rights-of-way (ROW) to obtain EECs. The conceptual model for the resident ial scenario integrates simulta neous modeling of the individual use scenario with an impervious scenario. This approach assumes that no watershed is completely covered by either the 1⁄4 acre lot (the basis for the residential scenario) or undeveloped land (the basis for the ROW scenar io) for residential and ROW use patterns; therefore, differential amounts of runoff will oc cur within the watershed. The impervious scenario was developed to repr esent the paved areas within a watershed not including roads, parking lots, sidewalks, and build ings outside the 1⁄4 acre lot (the 1⁄4 acre lot scenario accounts for impervious surfaces such as buildings within th e represented area). By modeling a separate scenario for impervious surfaces, it is also pos sible to estimate that amount of exposure that could occur when the pesticide is oversprayed onto this surface. Using two scenarios in tandem requires post-processing of the m odeled output in order to derive a weighted EEC that represents the contribution of both the pervious ( i.e. , residential and ROW scenarios) and the impervious surfaces. A Microsoft Excel spreadsheet has been developed that allows for the weighting and aggregation of exposure from both scenarios. The daily time series from each model run should be copied from the times series file (NAME_TS .out) generated from the PRZM graphical user interface (PE5.pl) into the spreadsheet provided. The time series data are then weighted based on percentage of impervious surface, the percen tage of the pervious surface treated, and an adjusted time series is created. Rolling aver ages for the relevant durations of exposure ( e.g. , 21 day and 60 day averages) are calculated, and the rele vant one-in-ten year return EEC is generated from these distributions.

For the purposes of risk assessment it will be assu med that 1% of the application rate could reach the impervious surfaces surrounding each residential lot. This am ount of overspray is not based on empirical data (no publicized studies on th is occurrence have b een found in the open literature); however, the assumption is consistent with the standard assumption of 1% spray drift65 with ground applications in ecological risk assessmen ts. In general, incor poration of impervious surfaces into the exposure assessment results in increasing runoff volume in the watershed, which tends to reduce overall pesticide exposure assuming 1% overspray to the impervious surface. Alternative assumptions for percent impe rvious surfaces, percentage of use site treated, and percentage of overspray may be considered in order to characterize the assumptions of the ecological risks assessment in the context of the individual exposure assessment and risk conclusions. For example, previously tested assumptions used in the endangered species assessments may be considered for characterization ( i.e. , 10% and 30% impervious surfaces, 10% lot treated, and 0% and 10% overspray) unless other relevant values can be determined ( i.e.

, modeling may be completed for the impervious su rface with 0% and 10% overspray to provide lower and upper bound values). The results of these alternate modeling exercises may be discussed in the assessment.

Given the aquatic toxicity of permethrin and its likelihood to occur in se diment, the Agency will also consider the potential expos ures resulting from be nthic/ sediment concentrations (EECs). Pore water concentrations are commonly used to predict toxicity of non-ionic substances in sediments and characterize exposure to organisms th at spend time in or near sediments (Di Toro et al. 1991; US EPA 2002). PRZM/ EXAMS estimat es 1-in-10-year peak and 21-day mean EECs for pore water.

To estimate exposure related to releases of pe rmethrin from domestic wastewater treatment plants, the Agency will rely on the Office of Pollution Prevention and Toxics (OPPT) model, Exposure and Fate Assessment Screening Tool (EFAST, version 2.0, or EFAST2, 2007). From this model, the Agency will use the “Down-the-Dr ain” module, which is designed for releases to domestic wastewater treatment. It is suitable for all the sources of permethrin that could potentially be exposed through a “down-the-drain” scenario. The model provides screening level estimate concentrations of chemicals in surface water that may result from household uses and the disposal of consumer products into wast ewater using a few simple input parameters (production volume and fraction of the chemi cal removed during wastewater treatment).

There are two possible scenarios whereby permet hrin residues can enter the aquatic ecosystem due to treatment to cattle. First, multiple cattle th at are treated with permethrin can directly enter a water body, and second, rainfall can cause washo ff of permethrin residu es to be transported from treated multiple cattle to water bodies via runoff. For these cases, surface water concentrations will be calculated using the ma ximum mass of permethrin per animal, spilling into a standard farm pond of 1 ha area and 2 m depth or a volume of 2.0 x 10 7 L. Surface water EECs will be calculated utilizing a suitable pr ogram which considers the soil-water partition coefficient and the depth of the sediment laye r such as the KdCalc (v.1.0 10/02/02). Certain assumptions are required for these scenarios. For example, for the first scenario, 20 treated cattle may be assumed to enter the water and for the se cond scenario, a 1000 treated cattle feedlots may be assumed (USDA NASS data). 25 A maximum of 100% of the active ingredient is assumed to wash-off cow hide for pour on products.

25 http://www.nass.usda.gov/Surveys/Guide_to_NASS_Surveys/Cattle_On_Feed/index.asp (accessed 02/01/11) “Feedlots with 1,000 or more head capacity represent about 85 percent of all fed cattle in the U.S.”66 Exposure estimates for terrestrial animals assumed to be in the ta rget area are derived using the T-REX model (version 1.3.1, 12/07/2006). This spr eadsheet-based model cal culates the residues on avian and mammalian food items along with the dissipation rate of a chemical applied to foliar surfaces (for single or multiple applications) in order to estimate acute and reproductive risk quotients. T-REX calculates EECs and risk quotients based on both the upper bound and mean residue concentrations as presented by Hoerger and Kenaga (1972) and modified by Fletcher et al. (1994). These concentrati ons are determined using nomograms that relate application rate of a pesticide to residues remaining on dietary ite ms of terrestrial organisms. EECs for terrestrial plants inha biting dry and wetland areas are derived using TerrPlant (version 1.2.2, 12/26/2006). This model uses estimates of pe sticides in runoff and in spray drift to calculate EECs. EECs are based upon solubilit y, application rate and minimum incorporation depth.

As indicated in Table 3.1 and its associated text in Section 3 , permethrin appears to have some potential to bioconcentrate in aqua tic organisms and it appears that th ere is also some potential to biomagnify in terrestrial organisms. The poten tial for bioaccumulation of permethrin will also be examined in the risk assessment. Because permethrin has a fairly high K OW (1.3 x 10 6 ) and the chemical may be persistent in water and sedi ments, there is a potenti al for bioaccumulation. The maximum bioconcentration factor was 570- 610x for whole fish and depuration rate is moderate (half depuration time of 4.7 days, MRID Nos. 41300401, 41300402 and 41300403). Bioaccumulation will be assessed using the results from bioaccumulation in fish studies, as well as the KABAM model (K OW (based) Aquatic BioAccumulation Model, version 1.0, 2009), adjusting for biotransformation rates. KABAM is used to estimate potential bioaccumulation of hydrophobic organic pesticides in freshwater aquatic ecosystems and risks to mammals and birds consuming aquatic organisms whic h have bioaccumulated these pest icides. Monitoring data and biotransformation rates in terrestrial species will also be evaluated, to assess the potential for bioaccumulation in terrestrial food webs.

7.3. Measures of Effect

Ecological effects data are used as measures of di rect and indirect effects to biological receptors. Data are typically obtained from registrant-submitte d studies or from literature studies identified by ECOTOX. The ECOTOX database provides more ecological effects data in an attempt to bridge existing data gaps. EC OTOX is a source for locating singl e chemical toxicity data and potential chemical mixture toxicity data for aq uatic life, terrestrial plants, and wildlife. ECOTOX was created and is maintained by the US EPA, Office of Research and Development, and the National Health and Environmental Ef fects Research Laboratory's Mid-Continent Ecology Division.

The acute measures of effect used fo r animals in this assessment are the LD 50 , LC 50 and EC 50

. LD stands for "Lethal Dose", and LD 50 is the amount of a material, given all at once, that is estimated to cause the death of 50% of the test organisms. LC st ands for “Lethal Concentration” and LC 50 is the concentration of a chemical that is estimated to kill 50% of the test organisms. EC stands for “Effective Concentration” and the EC 50 is the concentration of a chemical that is67 estimated to produce a specific effect in 50% of the test organisms. Endpoints for chronic measures of exposure for listed and non-lis ted animals are the NOAEL/NOAEC and NOEC. NOAEL stands for “No Observed-Adverse-Effect-Level ” and refers to the hi ghest tested dose of a substance that has been reported to have no harm ful (adverse) effects on test organisms. The NOAEC ( i.e. , “No-Observed-Adverse-Effect-Concentration” ) is the highest test concentration at which none of the observed effects were statisti cally different from the control. For non-listed plants, only acute e xposures are assessed ( i.e. , EC 25 for terrestrial plants and EC 50 for aquatic plants); for listed plants either the NOAEC or EC 05 is used.

Information on the potential effects of permethrin on non-target animals is also collected from the Ecological Incident Information System (EIIS) and Aggregrate Incident Reports. The EIIS is a database containing adverse e ffect (typically mortality) report s on non-target organisms where such effects have been associated with the use of pesticides. Informa tion on incidents involving avian species is also provided through the Av ian Monitoring Information System (AIMS), which is maintained by the American Bird Conservancy.

Where available, sub-lethal effects observed in both registrant-submitted and open literature studies will be evaluated qualitatively. Such effects may include behavioral changes ( e.g. , lethargy and changes in colora tion). Quantitative assessments of risks, though, are limited to those endpoints that can be di rectly linked to the Agency’s assessment endpoints of impaired survival, growth and reproduction.

The assessment of risk for direct effects to non- target organisms makes the assumption that the toxicity of permethrin to birds is similar to te rrestrial-phase amphibians and reptiles. The same assumption is made for fish a nd aquatic-phase amphibians.

7.4. Integration of Exposure and Effects

Risk characterization is the integration of e xposure and ecological effects to determine the potential ecological risk from the use of pestic ides and the likelihood of direct and indirect effects to non-target organisms in aquatic and te rrestrial habitats. The exposure and toxicity effects data are integrated in order to evaluate the risks of adverse ecological effects on nontarget species. For the assessm ent of risks, the risk quotient (RQ) method is used to compare exposure and measured toxicity va lues. EECs are divided by acute and chronic toxicity values. The resulting RQs are then compared to the Agency’s Levels of Concern (LOCs) (USEPA 2004). These criteria will be used to indicate wh en permethrin uses, as directed on the label, have the potential to cause advers e direct or indirect effects to non-target organisms. In addition, incident data from the EIIS will be consider ed as part of the risk characterization.

.

7.5. Deterministic and Probabilistic Assessment Methods

The quantitative assessment of risk will primarily depend on the deterministic point-estimate based approach described in the risk assessment. An effort may also be made to further qualitatively describe risk using probabilistic to ols that the Agency has developed. These tools68 have been reviewed by FIFRA Scientific Advisory Panels ( http://www.epa.gov/sc ipoly/sap/index.htm ) and have been deemed as appropriate means of refining assessments where deterministic approaches have identified risks.

7.6. Endangered Species Assessments

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency will evaluate risks to Federally-listed th reatened and/or endangere d (listed) species from registered uses of permethrin. This asse ssment will be conducted in accordance with the Overview Document (USEPA 2004), provisi ons of the ESA, and the Services’ Endangered Species Consultation Handbook (USFWS/NMFS, 1998).

The assessment of effects associat ed with the registration of pe rmethrin is based on an action area. The action area is considered to be the ar ea directly or indirectly affected by the federal action, as indicated by the exceedance of Agency Le vels of Concern (LOCs) used to evaluate direct or indirect eff ects. The Agency’s approach to defi ning the action area under the provisions of the Overview Document (USEPA 2004) considers the results of the risk assessment process to establish boundaries for that action area with the understandi ng that exposures below the Agency’s defined LOCs constitute a no-effect threshold. For th e purposes of this assessment, attention will be focused on the footprint of the action ( i.e. , the area where permethrin application occurs), plus all areas where offsite transport may result in potential exposure that exceeds the Agency’s LOCs. Specific measures of ecological effect that define the action area for listed species include any direct and indirect effects and/ or poten tial modification of its critical habitat, including reduction in survival , growth, and reproduction as well as the full suite of sub-lethal effects available in the effects lite rature. Therefore, the action area extends to a point where environmental exposures are below any measured lethal or sub-lethal effect threshold for any biological entity at the whole or ganism, organ, tissue, and/ or cellular level of organization. In situations where it is not po ssible to determine the threshold for an observed effect, the action area is not spatially limited a nd is assumed to be the entire United States.

7.7. Drinking Water Assessment

A drinking water assessment will be conducted to support future human health risk assessments of permethrin should it be required, based on al l the available environmental fate information. The drinking water assessment will incorporate model estimates of permethrin in surface and ground waters. Concentrations in surface waters will be estimated using FQPA Index Reservoir Screening Tool (FIRST, v.1.1.1, 12/18/07) (or subs equently using PRZM/ EXAMS, with the Index Reservoir – for description see above – if refinements are required). Ground water estimates of concentrations will be obtained using the Screening Concentration In GRound Water (SCI-GROW) model (v.2.3, July 2003). The drinking water assessment will also include a summary of available surface a nd ground water monitoring data.

7.8. Endocrine Disruptor Screening Program

As required under FFDCA section 408(p), EP A has developed the Endocrine Disruptor69 Screening Program (EDSP) to determine whether certain substances (inc luding pesticide active and other ingredients) may have an effect in humans or wildlife si milar to an effect produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator may designate.” The EDSP employs a two-tiered ap proach to making the statutorily required determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the estroge n, androgen, and or thyroid (E, A, or T) hormonal systems. Chemicals that go th rough Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stag e of the EDSP where EPA will determine which, if any, of th e Tier 2 tests are necessary base d on the available data. Tier 2 testing is designed to identify a ny adverse endocrine related eff ects caused by the substance, and establish a dose-response relationship between the dose and the E, A, or T effect.

Between October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 chemicals, which contains 58 pesticid e active ingredients and 9 inert ingredients. This list of chemicals was selected based on th e potential for human exposure through pathways such as food and water, residen tial activity, and certain post-applic ation agricultural scenarios. This list should not be construed as a lis t of known or likely e ndocrine disruptors.

Permethrin is among the group of 58 pesticide active ingredients on the initial list to be screened under the EDSP. The Agency will review the EDSP Tier 1 data and any “other scientifically relevant information” submitted in response to test orders. Based on this review the Agency will determine the need for additional testing. For fu rther information on the status of the EDSP, the policies and procedures, the list of chemicals, the test guidelines and the Tier 1 screening battery, please refer to the following website: http://www.epa.gov/endo/

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7.9. Preliminary Identification of Data Gaps

The California Department of Pesticide Regul ation (CDPR) placed pe rmethrin and other synthetic pyrethroids into reevaluation in 2006. Ce rtain data requirements were imposed to those pyrethroids. EPA is already in communication with CDPR and their data should also be submitted to the Agency. More information on the CDPR reevaluation program for pyrethroids is located at http://www.cdpr.ca.gov/docs/registration/ reevaluation/chemicals/pyrethroids.htm

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7.9.1. Environmental Fate

After evaluation of the availabl e data for permethrin, the follo wing data gaps for registration review have been identified.

Guideline Studies:

835.2240 Aqueous Photolysis - The solubility of permethrin in water is 0.0055 ppm and the available study was conducted at a concentra tion of 0.05-0.06 ppm, which is around 10 times higher. Furthermore, up to 91% of AR was adso rbed to the walls of th e test vials during the70 study. After initially found to be unacceptable, th e registrant submitted two literature articles on the aqueous photodegradation of pe rmethrin, and a previous review indicated that a good faith effort was made to provide information regardin g this data requirement; however,the review did not appear to explain clearly the problems found in the study . The study does not provide a reliable half-life value, since a large percentage AR was in the walls of the test vial. Furthermore, there is uncertainty regarding the possibi lity of formation of major degradates. This study was previously considered acceptabl e; however, upon further inspection, EFED has downgraded it to supplemental. In order to pr ovide reliable data on the aqueous photolysis behavior of permethrin, a new study is required. The study shoul d address the above mentioned deficiencies, provide a reliable a queous photolytic half-life value, and information about possible degradates of permethrin.

835.4100 Aerobic Soil Metabolism - There is an aerobic soil metabolism study, conducted on a single soil system, which is deemed acceptable. Du e to the fact that only one soil half-life is available, there is uncertainty related to the magn itude of the half-life fo r permethrin in soils. According to current guidelines, aerobic soil meta bolism studies with one soil type are generally sufficient for the evaluation of transformation pathways. Rates of transformation should be determined in at least three additional soils (per Fate, Transport and Transformation Test Guidelines – OCSPP Guideline 835.4100 & 835.4200). At this time, aerobic soil metabolism studies are required to be conducte d in three additional different so ils in order to fulfill current OCSPP guideline requirements. Th e new studies will provide thr ee additional half-lives in different soils, resulting in mo re knowledge and certainty related to the behavior and persistence of permethrin in aerobic soils. For meta bolism studies, domestic soils are preferred.

835.4200 Anaerobic Soil Metabolism – The available study, which was considered acceptable, only lasted 60 days of anaerobic incubation, at which time 65-72% AR remained as undegraded parent permethrin. Furthermore, it was performe d on a single soil system. Thus, it supplies only very limited information, with only a few samp ling periods. According to current guidelines, anaerobic studies with one soil t ype are generally sufficient for the evaluation of transformation pathways. Rates of transformation should be dete rmined in at least three additional soils (per Fate, Transport and Transfor mation Test Guidelines – OCSPP Guideline 835.4100 & 835.4200). The registrant is required to perform new anaerob ic soil metabolism studies in three different soils in order to fulfill current OCSPP guide lines and to address the above mentioned deficiencies. The new studies will provide three additional half-liv es in different soil systems, resulting in more knowledge and ce rtainty related to the behavior and persistence of permethrin in anaerobic soils. For metabolism st udies, domestic soils are preferred.

835.4300 Aerobic Aquatic Metabolism - In the available st udy, which was considered acceptable, the treatment rate was 1 ppm, wh ich greatly exceeds the solubility limit of permethrin; furthermore, the study la sted only 30 days, at which time ≥ 56% AR was undegraded permethrin (sum of cis- plus trans -isomers); and finally, only one water/ sediment system (from Wilson, NC) was analyzed. According to the OCSPP Fate, Transport and Transformation Test Guidelines (835.4300 & 835.4400) “At least two sediment s and their associated waters are used for both the aerobic and the anaer obic studies respectively... However, there may be cases where more than two aquatic sediments should be used, fo r example, for a chemical that may be present in freshwater and/or marine environments. Se diments should be representative of intended use71 sites.” Since permethrin has a high potential for use near estuarine/ marine areas, one of the required sediment systems should be from estuar ine/ marine environment. EFED is requiring two additional different sedime nt systems for permethrin, one of which should be of marine origin and the other of freshwater origin, in order to fulfill current OCSPP guideline requirements, to provide two addi tional half-lives in different aquatic sediments, resulting in more knowledge and certainty related to the beha vior and persistence of permethrin in aerobic aquatic environments, and to address the a bove mentioned deficien cies found during the screening of the available study. For the metabo lism studies, domestic se diments are preferred.

835.4400 Anaerobic Aquatic Metabolism – A study is available in one soil/ sediment system which was considered acceptable. However, upon examination of the study, it was found that it was conducted at a concentration th at greatly exceeded the solubility limit of permethrin (study conducted at 1 ppm, compared to a solubility of 0.0055 ppm) . This could promote the partitioning of the chemical with the sediment phase. Furthermore, the system was amended with D -(+)-glucose to promote anaerobicity; however, no redox potential and/ or oxygen content were measured during the study to confirm that the system was fully anaerobic. Due to the above mentioned problems, there is uncertainty regarding the behavi or of permethrin in typical anaerobic aquatic environments. According to OCSPP Fate, Tran sport and Transformation Test Guidelines (835.4300 & 835.4400) “At least two sediment s and their associated waters are used for both the aerobic and the anaer obic studies respectively... However, there may be cases where more than two aquatic sediments should be used, fo r example, for a chemical that may be present in freshwater and/or marine environments. Se diments should be representative of intended use sites.” At this time, EFED is requiring anaer obic aquatic metabolism st udies conducted with two water/ sediment systems. Since permethrin ha s a high potential for use n ear estuarine/ marine areas, one of the required sedime nt systems should be from estuarine/ marine origin, and the other of freshwater areas, in order to fulfill current OCSPP guide line requirements, to provide confirmatory data and two additional half-lives in different aquatic sediments, resulting in more knowledge and certainty regarding the behavior and persistence of permethrin in anaerobic aquatic environments, and to address the a bove mentioned deficien cies found during the screening of the available st udy. For all the metabolism studies, domestic sediments are preferred.

835.1230 Mobility – Adsorption/ Desorption Batch Equilibrium – One available study, which was originally considered acceptable, was perf ormed at concentrations ranging from 0.05 to 0.55 ppm, compared to a solubility limit of pe rmethrin in water of 0.0055 (up to 100 times the solubility limit of permethrin). Furthermore, a cosolvent concentr ation of 5% (acetonitrile) was used, compared to a recommended ≤ 0.1% (up to 50 times the maximum recommended cosolvent concentration). Even though Fre undlich correlations were good (r 2 ≥ 0.966), the 1/n values varied from 1.09 to 1.32, with only one of the va lues within the recommended range of 0.9-1.1. Furthermore, extensive degradation occurred, part icularly for the aquatic sediment. In another supplemental study, the adsorption constants (K d and K OC ) were much higher than for the previously mentioned study. For the later study, three of the soils had the same texture (sandy loam), the soils were sterilized using gamma irradiation, and the test was performed at above the solubility limit (the highest te st concentration was 0.2 ppm, or ~ 36 times permethrin’s solubility limit), which may promote adsorpti on. However, it was noted that the cosolvent concentration used was lower at 0.25% acetonitrile (recommended ≤ 0.1%). EFED has reevaluated the72 acceptable study, and due to the above mentioned pr oblems, has downgraded it to supplemental. There is a high degree of uncertainty w ith respect to the magnitude of the K d and K OC values for this chemical due to the observed differences from one study to the other, and they are thus, not considered reliable. EFED believes that a new study will greatly impr ove the understanding of the mobility of permethrin, and provide suitable information a bout the level of partitioning of permethrin in soil and water. Therefore, a new study addressing all th ese deficiencies is required.

835.6100 & 835.6200 Environmental Chemistry Methods (ECMs), and Independent Laboratory Validations (ILVs), for Soil, Water and Sediment . ECMs associated with the Terrestrial Field Dissipation studies (Fie ld dissipation §158.1300; OCSPP guidelines 835.6100 & 835.6200), along with successful confirmatory method trials (validation) by an independent laboratory ( i.e. ILVs), are required. If there is risk concern for a given taxon, ECMs should be available for the environmental media in whic h organisms of the taxon reside. These ECMs should have limits of quantitation for the residues of concern that are lower than the relevant toxicological levels of concern. Previous revi ews on permethrin indica te that there is high concern for acute and chronic toxi city to aquatic animals, includi ng those living in the benthos. Certain scenarios triggered acute and chronic levels of concern for freshwat er and/ or estuarine/ marine aquatic invertebrates and/ or for fish and/ or organisms liv ing in the benthos. Therefore, ECMs for water and sediment are required in addition to the ECM for soil. The ECMs should include parent and those residue s found in the laboratory stud ies that exceeded 10% of the applied. Based on the available data at this time , the following appear to be the residues of concern for each media, but this could cha nge, based upon the results of newly submitted environmental fate studies: Soil – parent, m -PBA and trans -DCVA Water and Sediment – parent, m -PBA, m -PBalc, cis -DCVA and trans -DCVA The registrant is encouraged to submit state-of-the-art environm ental chemistry methods; further, multi-residue methods (MRMs) for soil, water and se diment are preferred, if applicable. There is no method for permethrin published in the Agency’s ECM website. 26 One ECM/ILV combination has been submitted to the Agenc y, which is currently in review (MRID# 47053001 and 47053002). The Agency will verify the suitability of this method and the appropriateness of its levels of quantitation. At this time, no speci fic methods have been id entified for the analysis of m -PBA, cis - or trans -DCVA. A full description of the method validation procedures performed by an independent laboratory should also be submitted. It should include the following information (Corbin et al. 2006): (a) Recovery level(s) of the test compound(s) from the soil, water and sediment (substr ates) at various relevant fortific ation level(s) using the residue analytical methodology; (b) a valid ated method sensitivity level; (c) results of the study and statistical test applied, including a stepwise presentation of the pr ocedure for calculating percent recovery from the raw data; (d) all the data/ in formation necessary to independently verify the results; (e) summary of the re sults; and, (f) discussion and conclusions of the results.

Non-Guideline Studies:

Leachability from Treated Wood – A study is required for permet hrin. It should be conducted

26 Available at url: http://www.epa.gov/oppbead1/methods/ecmindex.htm73 using TEP and applied to the wood as indicated in the label, following the American Wood Preservers Association Standard Method of Determining the Leach ability of Wood Preservatives (E11, edition 06 or E1106). The registrant should provide a protocol to be evaluated by the Agency prior to performing the study.

POTW Treatability Study – The Agency has recently requested and provided comments on a protocol developed by the Pyre throid Working Group (PWG) for a bench scale study of waste water treatment, to assess the percentage rem oved in the biosolids by the treatment, the amount that would degrade during treatment, and the am ount that would remain in the waste water. These data would be used to inform removal pe rcentages by waste water treatment, which is an input to the Exposure and Fate A ssessment Screening Tool’s (E-F AST) down-the-drain module. The Office of Pesticide Programs will continue to confer with the Office of Water with the goal of refining our down-the-drain asse ssment for registration review. It is the respons ibility of the registrant to ensure that perm ethrin is included in the study completed by the PWG or conduct a similar study on its own (following subm ission of a protocol for review).

The Agency received comments from stakeholde rs with concerns rega rding the value of a POTW Treatability Study and its representativene ss of numerous treatment plant designs. EFED recognizes that such differences in plant design and operation may affect removal efficiencies, which is why it is proposing to require a POTW treatability study for permethrin, to support its EFAST2 down-the-drain modeling. EFED is current ly working with the re gistrant on the design of this study to best meet the Agency’s environmental risk assessm ent needs. Part of the design of this study will need to address factors that the commenters present ( i.e. , the effect of differences in POTW design and operation on remova l efficiencies) to the extent practicable. This may involve differences in experimental conditions and/ or the use of POTW simulation models to address these concerns . The ability to extrapolate th e bench scale results to results from available POTW monitoring data will also be evaluated. The forthcoming environmental risk assessment would address the uncertainty involved in the inte rpretation and extrapolation of results from the POTW treatabil ity study to the national scale.

The Agency is actively evaluating the extent to which ecological risk from permethrin via land application of biosolids should be addressed in its forthcoming e nvironmental fate and ecological risk assessment and by extension, any additional da ta that may be required. As part of this evaluation, OPP is working closely with the Office of Water which re gulates land application of biosolids under the Clean Water Act.

EFED is unaware of any studies that suggest inhibition of PO TW treatment processes is a significant risk due to documented pyrethroid exposures, including permethrin. Furthermore, EFED considers effects on POTW treatment processes to be beyond the scope of its environmental risk assessments.

Table 7.1 lists the status of the environmental fate data requirements for permethrin.

Table 7.1. Summary of Environmental Fate Data Requirements for Permethrin74 Study Identification Use
Pattern 1 Does EPA Have Data To Satisfy This Requirement? Bibliographic Citation Must Additional Data Be Submitted Under FIFRA

3(c)(2)(B)?

§158.1300 ENVIRONMENTAL FATE

Degradation Studies-Lab :

835.2120 Hydrolysis 1,2,3 Yes 00102043 No

835.2240 Photodegradation in
Water 1,2,3 Partially 40242801 Yes 2

835.2410 Photodegradation on Soil 1,2,3 Yes 40190101 No

835.2370 Photodegradation in Air 1,2,3 No Not Available No 3

Metabolism Studies-Lab :

835.4100 Aerobic Soil 1,2,3 Partially 42410002 Yes 4

835.4200 Anaerobic Soil 1,2,3 Partially 41970601 Yes 5

835.4300 Aerobic Aquatic 1,2,3 Partially 43938201 Yes 6

835.4400 Anaerobic Aquatic 1,2,3 Partially 43982001 Yes 7

Mobility Studies :

835.1230 Leaching – Adsorption/ Desorption 1,2,3 Partially 41868001, 45170102, 43424901 Yes 8

835.1410 Volatility (Lab) 1,2,3 No Not Available No 3

835.8100 Volatility (Field) 1,2,3 No Not Available No 3

Dissipation Studies-Field :

835.6100 Terrestrial Field Dissipation 1,2,3 Yes 42359109 No

835.6200 Aquatic Field Dissipation 1,2,3 Yes 44030501 No

835.6300 Forestry Dissipation 1,2,3 No Not Applicable Not Applicable

835.6100 & 835.6200 Environmental Chemistry Methods (ECMs) and Independent Laboratory Validations (ILVs) 1,2,3 Partially 47053001, 47053002 Yes 10

Ground Water Monitoring Studies :

835.7100 Ground Water Monitoring 1,2,3 No Not Available No75 Table 7.1. Summary of Environmental Fate Data Requirements for Permethrin

Study Identification Use Pattern 1 Does EPA Have Data To Satisfy This Requirement? Bibliographic Citation Must Additional Data Be Submitted Under FIFRA

3(c)(2)(B)?

§158.1100 SPRAY DRIFT
201-1 Droplet Size Spectrum 1,2,3 Yes 40954101, 43173801 No 9

202-1 Drift Field Evaluation 1,2,3 Yes 43173801 No 9

Other Studies :

Leachability from Treated Wood 1,2,3 No Not Available Yes 11

POTW Treatability Study Indoor Uses No Not Available Yes 12

1. Use Patterns: 1=Terrestrial/Food; 2=Te rrestrial/Feed; 3=Aquatic/Food or Non-Food. 2. The solubility of permethrin in water is 0.0055 ppm and the study was conducted at a concentration of 0.05-0.06 ppm; furthermore, up to 91% of AR was in the walls of the test vials during the study. The registrant should conduct a new confirmatory study addressing these issues. 3. Data requirement was waived based on the low vapor pressure and Henry’s Law Constant for permethrin. 4. The registrant conducted studies with only one soil system. According to current OCSPP guidelines, four soils are required. 5. The available study only lasted 60 days anaerobic incubation, at which time, 65-72% AR remained as undegraded parent permethrin. Furthermore, it was conducted using only one soil, while the current OCSPP guideline requires four soils. A new study should be conducted. 6. In the available study, the treatment rate was 1 ppm, which greatly exceeds the solubility limit of permethrin; the study lasted only 30 days, at which time ≥ 56% AR was undegraded permethrin (sum of cis and trans -isomers); and only one water/ sediment system (from Wilson, NC) was analyzed. The registrant should conduct a new study, using two water/ sediment systems, one of which should be of marine origin. 7. Only one sediment system was evaluated while current guid elines require at least two. Furthermore, for the available study, various deficiencies were found: the study was conducted at a concentr ation that exceeded the solubility limit (1 ppm vs. solubility limit of 0.0055 ppm) and no redox potential or oxy gen content measurements were performed to confirm that the system was fully anaerobic. A new study, performed with two water/sediment systems is required, one of which should be of marine origin. 8. Two studies conducted with the parent compound had deficiencies (described above). A new study, addressing those deficiencies, is required. 9. Data requirements covered by submission of the Spray Drift Task Force. 10. The data requirement remains unfulfilled for permethrin, pending evaluation of available studies. 11. It is preferred that the registrant provided a protocol to be evaluated by the Agency prior to performing the study. 12. A protocol for this study was submitted by the Pyrethroid Working Group and comments have been provided by EFED.

7.9.2 Ecological Effects

For registration review, the follo wing studies are being requeste d to fulfill any data gaps:

Guideline Numbers: 850.2100 Study Title: Avian acute oral t oxicity test (passerine species) Acute avian oral toxicity data are required for either one waterfowl or one upland game species76 and one passerine species under the 40 CFR Pa rt 158 (CFR 40 2008) data requirements for conventional pesticides. In the latest Agency ecological risk assessment for permethrin, acute estimates of risk for birds were not generated fo r because the acute oral avian effects data show no treatment-related mortality to either mallard ducks ( Anas platyrhynchos ), Japanese quail ( Coturnix coturnix ) or ring-necked pheasants ( Phasianus colchicus ) at levels ranging from >2,000 to >42,706 mg a.i./kg-body weight (USEPA 2008a; MRIDs 00112938, 41888401, 00042142, 00042121). Because passerine species have higher metabolic rates due to their smaller sizes than either waterfowl or upland ga me bird species and because they may utilize different metabolic pathways, they may be more or less sensitive to permethrin. In addition, an open literature study has doc umented the increased sensitivity of canaries ( Serinus sp. ) to another pyrethroid, beta -cyfluthrin (Addy-Orduna et al , 2011).

One study examining the toxic effects of permethrin to a passerine species has been submitted to the Agency. A permethrin (PP 557, 92% w/v ac tive ingredient) acute oral limit test was conducted on starlings ( Sturnus vulgaris ) (MRID 00042144). This study was classified as invalid due to lack of information in the study repor t, including documentation that regurgitation was examined after the initial dose a nd that food was withheld prior to dosing. In order to properly characterize risk to passerines, an avian oral toxicity test is required for passerine birds. A passerine study protocol must be submitted for revi ew by the Agency prior to initiation of the study.

Guideline Number: 850.1020 Study Title: Acute Freshwater Invertebrate Toxicity (TEP) Because there are registered outdoor uses of permet hrin that may result in significant exposure to water bodies, acute toxicity data of permethrin TEPs with the synergist PBO and MGK-264 is requested for freshwater invertebrates. Produc ts with these synergis ts are likely to cause increased toxicity to nontarget aquatic species. Currently, no data is available to quantify the difference in toxicity for fish or invertebrates that may be conc urrently exposed to permethrin and these synergists compared to the active i ngredients alone. Therefore, the Agency is requesting acute toxicity studies of permethrinTEPs that are co-formulated w/ PBO and MGK264. Because available informati on indicates that greater toxic ity enhancement can occur at higher synergist-to-a.i. ratios, selection of th e TEPs for testing should include those TEPs with the highest synergist- to-a.i. ratio and are registered for outdoor uses. The recommended freshwater invertebrate te st species is the amphipod, Hyalella azteca

. H. azteca is recommended over other standard test species (e.g., Daphnia magna ) due to its much greater sensitivity to pyrethroids compared to D. magna

. Hyalella is also a recommended test species for sediment toxicity testing which enables toxicity extrap olations to be made among water column and benthic exposures within the same speci es. The 850.1020 test guideline for Gammarid amphipods is recommended with appropriate modifi cations to address specific testing needs of H. azteca . The registrant should submit a test protoc ol prior to conducting th ese TEP studies that documents the rationale for the TEP selecti on and details of the testing procedure for H. azteca

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The Agency notes that the ratios of synergist (P BO or MGK-264) to permethrin expected in the aquatic environment may be much greater than those used in the formulated products, due in part77 to the different fate properties of the synergists and permethrin. As available data suggest greater toxicity enhancement can occur at higher synerg ist-to-a.i. ratios, it is possible that greater toxicity enhancement may occur in the natural environment compared to that measured for formulated products. Therefore, to address this concern, th e Agency will attempt to bridge results from ongoing “comprehensive” synergist testing at varying synergist-to-a .i. ratios to address varying ratios of PBO/MGK-264 to permethrin that are expected to occur in aquatic ecosystems. However, should the available data be insufficient to enable scientifically defensible bridging to be conducted at the time of the forthcoming perm ethrin ecological risk assessment, the Agency may apply a “conservative” toxicity enhancement factor to address the uncertainty regarding differences in synergist-to-permethrin ratios in the aquatic environment vs. those tested using formulated products. The registrant may wish to submit additional data on permethrin/synergist toxicity at varying ratios that would be expected to occur in th e aquatic environment to address this potential uncertainty.

Guideline Number: 850.1075 Study Title: Acute Freshwater Fish Toxicity (TEP) Because there are registered outdoor uses that ma y result in significant exposure to water bodies, acute toxicity data of permethrin TEPs with the synergist PBO and MGK-264 is requested for freshwater fish. Products with th ese synergists are likely to caus e increased toxicity to nontarget aquatic species. Currently, no data is available to quantify the diffe rence in toxicity for fish or invertebrates that may be concurrently exposed to permethrin and these synergists compared to the active ingredients alone. Therefore, the Ag ency is requesting acut e toxicity studies of permethrin TEPs that are co-formulated w/ PB O and MGK-264. Because available information indicates that greater toxicity enhancement can occur at higher s ynergist-to-a.i. ratios, selection of the TEPs for testing should include those with the highest synergist- to-a.i. ratio and are registered for outdoor uses. The registrant s hould submit a test protocol prior to conducting these TEP studies that documents th e rationale for the TEP selection.

The Agency notes that the ratios of synergist (P BO or MGK-264) to permethrin expected in the aquatic environment may be much greater than those used in the formulated products, due in part to the different fate properties of the synergists and permethrin. As available data suggest greater toxicity enhancement can occur at higher synerg ist-to-a.i. ratios, it is possible that greater toxicity enhancement may occur in the natural environment compared to that measured for formulated products. Therefore, to address th is concern, the Agency will attempt to bridge results from ongoing “comprehensive” synergist tes ting at varying synergis t-to-a.i. ratios to address varying ratios of PBO/MGK-264 to permethrin that ar e expected to occur in aquatic ecosystems. However, should the available data be insufficient to enable scientifically defensible bridging to be conducted at the time of the forthcoming permethrin ecological risk assessment, the Agency may apply a “conservativ e” toxicity enhancement factor to address the uncertainty regarding differences in synergist-to -permethrin ratios in the aquatic environment vs. those tested using formulated products. The registrant may wish to submit additional data on permethrin/synergist toxicity at va rying ratios that would be exp ected in the aquatic environment to address this poten tial uncertainty.

Guideline Number: 850.102078 Study Title: Acute Freshwater Invertebrate Toxicity ( Hyalella azteca )

Acute water column tests with Hyallela azteca have been requested in other pyrethroid problem formulations based on the increased sensitivity of this species to pyrethroid insecticides. In the most recent permethrin assessment that looked at effects to aquatic invertebrates (USEPA 2008a), Hyallela azteca open literature data was used to calculate risk quo tients for aquatic invertebrates (Anderson et al. , 2005; ECOTOX Ref. #90039). This acu te toxicity endpoint was more sensitive than registrant-submitted aquatic i nvertebrate tests with water-column exposure to Daphnia magna . However, upon additional review, this study with H. azteca is determined to supplemental (will not be used quantitatively) in the upcoming Agency ecological risk assessment for permethrin. This decision is based on concerns with test substance stability during the study and high solvent control mortality (the solvent used was at levels approximately 20 times higher than Agency guideline recommendations for aquatic toxicity tests). An acute water column test examining the toxicity of permethrin to Hyalella azteca is required. The 850.1020 test guideline for Gammarid amphipods is reco mmended with appropriate modifications to address specific testing needs of H. azteca . The registrant should subm it a protocol prior to test initiation or submit any open literature studies that may fulfill this data gap.

Guideline Numbers: 850.1025 Study Title: Oyster acute toxi city test (shell deposition) No available studies examining the effects of permethrin on mollusks are acceptable for quantitative use in the upcoming ri sk assessment. Therefore, the Agency is requesting an acute toxicity test of permethrin in order to appropriately estimate acute toxicity to mollusks.

Guideline Number: 850.1350 Study Title: Aquatic Invert ebrate Life-Cycle (saltwater) Previously submitted studies indicate that estuarine/marine invertebrates are among the most chronically sensitive taxa to permethrin, with acu te effects expected belo w 1 μg a.i./L. While two estuarine/marine invertebrate chronic exposur e studies with permethrin are available to the Agency, the toxicity endpoints derived from these studies are considered highly uncertain. Specifically, one life-cycle study with mysids ( Americamysis bahia ) reports NOAEC and LOAEC values of 0.011 and 0.024 μg a.i./L based on mortality, but poor reproductive performance of the controls hindered the ev aluation of permethrin effects on reproduction (MRID 41315701). The other chronic permethrin st udy conducted with mysids was determined to be invalid because no raw data was reported to enable verification of results, stock solutions were accidentally switched and excessive deaths o ccurred due to mysids jumping from the test containers (MRID 40102001).

Furthermore, the need for a life cycle chronic toxicity of permethrin to estuarine/marine invertebrates is indicated based on its aquatic to xicity and environmental fate properties per 40 CFR Part 158 data requirements (October 26, 2007). Specifically: 1. Permethrin is intended for use such that its presence in estuarine/marine environment in significant c oncentrations is expected; 2. The acute LC/EC 50 for permethrin is substantia lly lower than the 40 Part 158 trigger value of 1 mg/L (0.019 μg/L for Americamysis bahia , MRID 40228401); and 3. Previous risk assessments have indicate d that the aquatic EEC s are > 0.01 of the acute LC/EC 50 values for permethrin, which is another condition for triggering an79 estuarine/marine invertebrate life cycle study. In the 2008 listed species assessment for permethrin, acute RQs for estuarine/marine invertebrates range from 2.48 (soil barrier treatment on fen cerows and hedgerows) to 305.56 (nursery uses and residential turf and orname ntals) for the 45 agricultural and nonagricultural scenarios assessed (USEPA 2008a).

As substantial advances in both analytical and biological test methods have occurred over the past two decades (the previously submitted studies were conducted in 1986 and 1989), it is highly likely that a repeat of th ese studies would yield results that are much more scientifically defensible. Without this study, estimation of chroni c risks to estuarine/marine invertebrates from permethrin exposure will involve substantial uncertainty.

Guideline Numbers and Study Titles:

 Test Method 100.4 (OCSPP 850.1770, in prep .); Whole sediment: chronic invertebrates freshwater ( Hyalella azteca )

 Test Method 100.5 (OCSPP 850.1760, in prep .); Whole sediment: chronic invertebrates freshwater ( Chironomus dilutus ) US EPA 2001,

 EPA 600/R-01/020 (OCSPP 850.1780, in prep .); Whole sediment: chronic invertebrates marine ( Leptocheirus plumulosus ) No chronic sediment toxicity tests for freshwater or marine invertebrates have been submitted to satisfy the Agency’s updated data requiremen ts for outdoor uses in 40 CFR Part 158 (October 26, 2007). For permethrin, available informati on indicates that bent hic organisms may be exposed via run-off or spray drif t applications used in agricu ltural, forest, and residential settings. Based on calculations in the most recent EFED assessment for permethrin where estimated sediment concentrations were calculat ed, the peak sediment porewater EECs predicted for permethrin ranged from 0.00364 ppm for barrier treatment to 1.62 ppb for nursery-pine seed orchard-high rate (US EPA 2008a). The upper end of this range exceeds 0.1 of the most sensitive acute LC/EC 50 (0.0212 μg a.i./L for the amphipod Hyallela azteca ), which satisfies one of the criteria for requiring chronic whole sediment toxicity testing under 40 CFR Part 158. Chronic reproductive effects were also seen in other aqua tic invertebrate taxa (daphnids and mysids), although at higher levels than acute effects were observed for amphipods.

Permethrin has a long expected half-life in sediment, based on submitted soil metabolism and aquatic metabolism studies (aerobic soil, 37 da ys; anaerobic soil, 204 days; aerobic aquatic metabolism, 38.2-42.9 days; anaerobic aquatic metabolism, 113-175 days) (MRIDs 42410002, 41970601, 43938201 and 43982001). These half-life values are substantially greater than 40 CFR Part 158 criterion of 10 days. The potential for persistent exposure from permethrin in sediment is also indicated by open lite rature studies on pyrethroids (Weston et al., 2004; Holmes et al., 2008; Weston and Lydy, 2010; Lao et al., 2010; Ding et al ., 2009).

The third set of trigger criteria for requiring chronic testing (K d > 50 or log K OW >3 or K OC > 1000) is also met for permethrin (K d ranges from 140-401, log K OW is 6.1, and K OC values range from 19,300 to 60,900). The physicoc hemical property triggers (K d , K OW and K OC ) reflect the propensity of the chemical to partition onto the part iculate or organic matter phases of sediments. Exceeding any one of the physicochemical propert y triggers listed above is sufficient for indicating the pesticide has reasonable potential for partitioning to the sediment compartment.80 For sediment studies involving pyrethr oids, chronic whole sediment tests on Hyalella azteca

, Chironomus tentans , and Leptocheirus plumulosus are requested. Although both are freshwater species, Hyalella and Chironomus differ substantially in their ecological niche ( i.e. , epibenthic v. infaunal species), physiology. Evidence in open literature suggests that Hyalella azteca is among the most sensitive aquatic invertebrates to permethrin based on acute water column tests (Weston and Lydy, 2010; Brander et al., 2009). Permethrin has the potential to en ter estuarine/marine water bodies based on current usuage patterns that include coastal ar eas. Therefore, testing is also required for an estuarine/marine sediment-dwelling invertebrate species.

Until the final OCSPP guidelines for chronic sediment toxicity tests are published, the registrant should submit a protocol to EFED for approval prior to test initiation.

 Test Method 100.4: Hyalella azteca 42-d Test for Measuring the Effects of Sediment Associated Contaminants on Survival , Growth, and Reproduction in USEPA 2000 Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates EPA 600/R-99/064 ( OCSPP 850.1770, in

prep. );

 Test Method 100.5: Life-cycle Test for Meas uring the Effects of Sediment-associated Contaminants on Chironomus dilutus (formerly known as C. tentans ) in USEPA 2000 Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates EPA 600/R-99/064 ( OCSPP 850.1760, in

prep. ); and

 Leptocheirus plumulosus in USEPA 2001 Method for Asse ssing the Chronic Toxicity of Marine and Estuarine Sediment-associ ated Contaminants with the Amphipod Leptocheirus plumulosus EPA 600/R-01/020 ( OCSPP 850.1780, in prep. ).

Guideline Numbers: 850.4150 and 850.4250 Study Title: Vegetative vigor a nd Seedling emergence, Tier II No acceptable toxicity data are currently available to assess the risk of permethrin to non-target terrestrial plants. Since permethrin has many outdoor uses, vegetative vigor and seedling emergence studies are required. In addition, registrants have reporte d three major terrestrial plant incidents involving permethrin alone or permethr in with piperonyl butoxide, a commonly used pyrethroid synergist. A total of 149 reported minor plant incidents are attr ibuted to permethrin use. Phytotoxicity data are needed to asse ss the impact of pestic ides on endangered and threatened non-target terrestrial plants.

Guideline Numbers: 850.4400 and 850.5400 Study Title: Aquatic Plant Growth (al gal and aquatic vascular plant toxicity), Tier II No acceptable toxicity data are currently available to assess the risk of permethrin to non-target aquatic nonvascular and vascul ar plants. Since permethrin has many outdoor uses, algal and aquatic vascular plant toxi city studies are requested with either permethrin technical or a typical end-use product.81 Table 7.2 lists the status of the ecological e ffects data requirements for permethrin.

Table 7.2. Ecological Effects Data Requirements for Permethrin.

Data Requirement Does EPA Have Data To Satisfy This Requirement?

(Yes, No, or

Partially) Bibliographic Citation (MRID) Must Additional Data Be Submitted Under FIFRA 3(c)(2)(B)?

§158.630 TERRESTRIA L ORGANISM TESTING

850.2100 Acute Avian Oral, Quail/Duck/Passerine Partially 00112938, 41888401, 00042142, 00042144 Yes 1

850.2200 Acute Avian Diet, Quail Yes 41888402, 00072845 No

850.2200 Acute Avian Diet, Duck Yes 00112939, 41888403 No

850.2400 Wild Mammal Toxicity N/A

850.2300 Avian Reproduction Quail Yes 42322901, 00110671 No

850.2300 Avian Reproduction Duck Yes 42322902, 00110670 No

§158.630 AQUATIC ORGANISM TESTING

850.1075 Acute Fish Toxicity Bluegill Yes 00110663, 00110657, 00097445 No

850.1075 Acute Fish Toxicity Rainbow
Trout Yes 00110657 No

850.1075 Acute Fish Toxicity (TEP) Partially 00110705, 42584004 Yes 2

850.1010 Acute Aquatic Invertebrate Yes 0043736, 00110662, 00043736, 00110663 No

850.1010 Acute Aquatic Invertebrate (TEP) Partially 00110662, 43740602, 42584002 Yes 2

850.1075 Acute Est/Mar Toxicity Fish Yes 41874901 No

850.1025 Acute Est/Mar Toxicity
Mollusk No N/A Yes

850.1035 Acute Est/Mar Toxicity Shrimp Yes 43492902 No

850.1075 Acute Est/Mar Toxicity Fish (TEP) No N/A No

850.1025 Acute Est/Mar Toxicity Mollusk (TEP) No N/A No

850.1035 Acute Est/Mar Toxicity Shrimp (TEP) No N/A No

850.1400 Early Life Stage Fish Yes N/A No82 Table 7.2. Ecological Effects Data Requirements for Permethrin.

Data Requirement Does EPA Have Data To Satisfy This Requirement?

(Yes, No, or

Partially) Bibliographic Citation (MRID) Must Additional Data Be Submitted Under FIFRA 3(c)(2)(B)?

850.1300 Life Cycle Aquatic Invertebrate (freshwater) Yes 43745701 No

850.1350 Life Cycle Aquatic Invertebrate (saltwater) No N/A Yes

850.1500 Life Cycle Freshwater Fish Yes Accession #263993 No

850.1730 Bioaccumulation in Fish Yes 41300401, 41300402, 41300403 No

Test Method 100.4 (OCSPP 850.1770, in prep.); Whole se diment: chronic invertebrates freshwater ( Hyalella azteca ) No N/A Yes 3

Test Method 100.5 (OCSPP 850.1760, in prep.); Whole se diment: chronic invertebrates freshwater ( Chironomus dilutus ) No N/A Yes 3

US EPA 2001, EPA 600/R-01/020 (OCSPP 850.1780, in prep.); Whole sediment: chronic invertebrates marine ( Leptocheirus plumulosus ) No N/A Yes 3

850.1020 Aquatic Invertebrate Acute Toxicity ( Hyalella ) No NA Yes 4

§158.660 PLANT PROTECTION TESTING

850.4100 Seedling Emergence (Tier II) No NA Yes 5

850.4150 Vegetative Vigor (Tier II) No NA Yes 5

850.4400 Aquatic Plant Toxicity using Lemna spp. (Tier II) No NA Yes 5

850.5400 Algal Toxicity (Tier II) No NA Yes 5

§158.490 INSECT POLLINATOR TESTING

850.3020 Honey Bee Acute Contact Yes 42674501 No

850.3030 Honey Bee Residue on Foliage Yes 42009301 No

850.3040 Field Test for Pollinators No NA In Reserve 683 NA = Not applicable because no citation is available.

1 One study examining the toxic effects of permethrin to a passerine species has been submitted to the Agency. A permethrin (PP 557, 92% w/v active ingredient) acute oral limit test was conducted on starlings ( Sturnus vulgaris ) (MRID 00042144). This study was classified as in valid due to lack of information in the study report, including documentation that regurgitation was examined after the initial dose and that food was withheld prior to dosing. An acute oral test examining the toxicity of permethrin to passerine species is required. A passerine study protocol must be submitted for review by the Agency prior to initiation of the study.

2 TEP studies on freshwater invertebrates and freshwater fish are required on a product containing permethrin and the synergist piperonyl butoxide in addition to a product containing permethrin and the synergist MGK-264. Permethrin may be co-formulated with either or both synergists, PBO and MGK-264, in numero us products. Because available information indicates that greater toxicity enhancemen t can occur at higher synergist-to-a.i. ra tios, selection of the TEPs for testing should include those with the highest synergist-to-a.i. ratio and are registered for outdoor uses. The preferred freshwater invertebrate test species is the amphipod, Hyalella azteca (using 850.1020 guideline for Gammarid amphipods with apporiate modifications). Freshwater fish tesing should follo w the 850.1075 test guideline. The registrant should submit a test protocol prior to conducting these TEP studies that documents the rationale for the TEP selection. 3 Test Method 100.4 : Hyalella azteca 42-d Test for Measuring the Eff ects of Sediment-associated Contam inants on Survival, Growth, and Reproduction in USEPA 2000 Methods for Measuring the Toxicity and Bio accumulation of Sediment-associated Contaminants with Freshwater Invertebrates EPA 600/R-99/064.

Test Method 100.5 : Life-cycle Test for Measuring the Effect s of Sediment-associat ed Contaminants on Chironomus dilutus (formerly known as C. tentans) in USEPA 2000 Methods for Measuring the Toxicity and Bioaccumulation of Sedimentassociated Contaminants with Freshwater Invertebrates, EPA 6001R-99/064.

USEPA 2001 : Method for Assessing the Chronic Toxicity of Marine and Estuarine Sediment-associated Contaminants with the Amphipod Leptocheirus plumulosus, EPA 6001R-0l/020.

Protocol must be submitted to the Agency for review and approval prior to study inception.

4 Acute water column tests with Hyallela azteca have been requested in other pyrethroid problem formulations based on the increased sensitivity of this species to pyrethroid insecticides . The registrant should submit a protocol prior to test initiat ion or submit any open literature data that may fulfill this data gap.

5 A Tier II study is expected to be required. The upcoming DCI will provide that a Tier I plant study may be conducted in lieu of a Tier II study with the understanding that any adverse effects observed by the Tier I study would necessitate conduct and submission of a Tier II study as well. The purpose of a Tier II study is to establish both a definitive No Observed Adverse Effect Concentration (NOAEC), or alternatively, a concentration at which th ere is a 5% observed inhibition effect (IC 05 ) to be used in a risk assessment and effects determination for endangered or threatened species (listed species), and a definitive IC 25 (concentration at which there is a 25% observed inhib ition effect) for assessing risk to non-listed nontarget plants.

6. As discussed in Section 4.1, the Agency is holding the requ irement for additional data on pollinator exposure and effects in reserve pending the outcome of the FIFR A SAP on Pollinator Risk A ssessment (scheduled for spri ng 2012) and receipt of additional data concerning permethrin risks to pollinators du ring public review of this Preliminary Problem Forumulation document.84 8. References

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Permethrin Environmental Fate Bibliography

161-1 Hydrolysis

MRID Citation Reference

42146 Holmstead, R.L.; Casida, J.E.; Ruzo, L.O. (1976?) Photochemical Re- actions of Pyrethroid Insecticides. (U npublished study received Aug 22, 1977 under 10182-3; prepared by Univ. of California, Dept. of Entomological Sciences, Pesticide Chemistry and Toxicology Laboratory, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096330-A)

65822 Allsup, T.L. (1976) Letter sent to Rout e List dated Apr 14, 1976: Hydrolysis of the FMC 33297 Insecticide: Analyt ical Report W-0103. (Unpublished study received Dec 29, 1980 under 10182-EX-19; prepared by FMC Corp., submitted by ICI Americas, Inc., Wilmi ngton, Del.; CDL: 244018-E)

97453 Rickett, F.E.; Knight, P.J. (1976) Ph otostability of Permethrin Isomers: Document Code HCDF 76-1. (Unpub lished study received Mar 17, 1982 under 59-200; prepared by Wellcome Foundation Ltd., England, submitted by Burroughs Wellcome Co., Research Tr iangle Park, N.C.; CDL:247048-A)

102043 Allsup, T.; Russell, K.; Fullmer, O. (1976) Hydrolysis of FMC 33297 Insecticide: W-0103. (Unpublished study received Dec 1, 1976 under 7G1891; prepared by FMC, submitted by ICI Un ited States, Inc., Wilmington, DE; CDL:096431-G)

102045 Holmstead, R.; Casida, J.; Ruzo, L. (1976) Photochemical Reactions of Pyrethroid Insecticides. Taken fr om: 172nd ACS National Meeting of the American Chemical Society; Aug 30, 1976, San Francisco, CA. (S.l.: s.n.). (Abstract; PEST 32; also In unpublished submission received Dec 1, 1976 under 7G1891; submitted by ICI United St ates, Inc., Wilmington, DE; CDL: 096431-K)

110613 Elliott, M.; Farnham, A.; Janes, N.; et al. (1973) NRDC 143: A More Stable Pyrethroid. Pages 721-728, In Procee dings, 7th British Insecticide and Fungicide Conference. ?S.l: s.n.|. (Also In unpublished submission received Dec 30, 1976 under unknown ad- min. no.; s ubmitted by ICI Americas, Inc., Wilmington, DE; CDL: 095685-B)

110627 Fujie, G.; Cardenas, B.; Torre, A.; et al. (1975) Hydrolysis of FMC 33297 Insecticide (Phase I): W-0047. (Unpublis hed study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Phila delphia, PA; CDL:096695-C)

110628 Holmstead, R.; Casida, J.; Ruz o, L.; et al. (1977) Pyrethroid Photodecomposition: Permethrin. (Unpublished study received Jan 3, 197889 under 279-3013; prepared by Univ. of California-- Berkeley, Dept. of Entomological Sciences, Pesticide Chemistry and Toxicology Laboratory, submitted by FMC Corp., Philadelphia, PA; CDL:096695-F)

110675 Brandau, E.; Goertler, M.; Robinson, R. (1975) Determination of Partition Coefficients for Carbofuran, FMC 33297, FMC 25213, certain Potential Metabolites and Two Benchmark Chem icals: Ana- lytical Report M-3779. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096697-N)

112936 Alvarez, M.; Dziedzic, J.; Durbetaki, A.; et al. (1977) Hydrolysis of FMC 33297: Report No. CGP-77-12. (Unpublis hed study re- ceived Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL:096695-E)

45369732 Burri, R. (1995) Hydrolysis Determinati on of (Inert Ingredients) at pH 5, 7, and 9: Lab Project Number: 340290: M9 419. Unpublished study prepared by RCC Umweltchemie AG. 67 p.

92142047 Leung, L. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00102043 and Related MRIDs 00112936. Pounce Insecticide Permethrin (FMC 33297)- Hydrolysis Study. Prepared by FMC CORP. 10 p.

161-2 Photodegradation-water

MRID Citation Reference

149595 Gronberg, R. (1984) Photodecomposition of [Phenyl-UL-[Carbon 14]] Baythroid in Aqueous Solution by Sunlight: Mobay Report 88598. Unpublished study prepared by M obay Chemical Corp. 13 p.

40242801 Amos, R.; Donelan, R. (1987) Permethrin: Photolysis in Sterile Water at pH5: Laboratory Project ID RJ0577B. Unpub lished study prepared by ICI Plant Protection Div, Jealott's Hill Research Station. 66 p.

42394706 Tanaka, F. (1992) Aqueous Photolysis of ?carbon-14| Vinclozolin at pH 5: Lab Project Number: 91153: M9205: 92-5098. Unpublished study prepared by BASF Corp. 56 p.

45369737 Burri, R. (1995) Photodegradation Study (Inert Ingredient) in Water at pH 5: Lab Project Number: 340312: M9420. Unpublished study prepared by RCC Umweltchemie AG. 59 p.

92142048 Leahey, J. (1990) ICI Americas Inc. Phase 3 Summary of MRID 40242801. Permethrin: Photolysis in Sterile Water at ph5: Report No. RJ0577B; Study No. PP557AG02. Prepared by ICI AGROCHEMICALS JEALOTT'S HILL RES. STATION. 14 p.

161-3 Photodegradation-soil90 MRID Citation Reference

42146 Holmstead, R.L.; Casida, J.E.; Ruzo, L.O. (1976?) Photochemical Re- actions of Pyrethroid Insecticides. (U npublished study received Aug 22, 1977 under 10182-3; prepared by Univ. of California, Dept. of Entomological Sciences, Pesticide Chemistry and Toxi- cology Laboratory, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096330-A)

60035 Elliott, M.; Farnham, A.W.; Janes, N. F.; et al. (1973) NRDC 145: A more stable pyrethroid. Proceedings of the 7t h British Insecticide Conference :721-728. (Also~In~unpublished submission received Feb 3, 1977 under 10182-EX8; submitted by ICI Ameri- cas, In c., Wilmington, Del.; CDL:228194-B)

65820 Hill, I.R.; Harvey, B.R.; Weissler, M. S. (1977) Permethrin: Degradation in River Sediments, River Water and in Flooded Soils: RJ0008 A. (Unpublished study received Dec 29, 1980 under 10182- EX-19; prepared by Imperial Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:244018-C)

66649 Elliott, M.; Farnham, A.W.; Janes, N. F.; et al. (1973) NRDC 143: A more stable pyrethroid. Pages 721-728,~In Pro ceedings, 7th British Insecticide and Fungicide Conference. N.P. (Also~In ~ unpublished submission received Feb 3, 1977 under 10182-EX-7; submitted by ICI Americas, Inc., Wilmington, Del.; CDL:228608-B)

89996 Arnold, D.J.; Hill, I.R. (1977) Permethrin : Extraction and Identi- fication of the Bound Residues of the Pesticide in Soil: Report Series TMJ 1513B; 5B 1/5. (Unpublished study received Dec 30, 1981 under 10182-64; prepared by Imperial Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070559-G)

110628 Holmstead, R.; Casida, J.; Ruz o, L.; et al. (1977) Pyrethroid Photodecomposition: Permethrin. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Univ. of California-- Berkeley, Dept. of Entomological Sciences, Pesticide Chemistry and Toxicology Laboratory, submitted by FMC Corp., Philadelphia, PA; CDL:096695-F)

110630 Kaufman, D.; Jordan, E.; Kayser, A. ; et al. (1977) The Effect of Soil Temperature on the Degradation of 14C- Carbonyl-cis, trans- Permethrin in Soil: Report No. 8. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by U.S. Agricultural Re- search Service, Agricultural Environmental Quality Institute and Univ. of Maryland, Dept. of Botany, submitted by FMC Corp., Philadelphia, PA; CDL:096695-J)

110631 Arnold, D.; Cleverley, B.; Hill, I. (1976) Permethrin: Laboratory Studies of the Degradation of the Pesticide in Soil: Report Series TMJ 1287 B. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096695-K)91 110632 Arnold, D.; Hill, I. (1977) Permethrin : Extraction and Identifi- cation of the Bound Residues of the Pesticide in Soil: Report Series 1513B. (Unpublished study received Feb 14, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096695-M)

110633 Kaufman, D.; Jordan, E.; Kayser, A. ; et al. (1977) Degradation of 14CCarbonyl Cis- and Trans-, and 14C-Met hylene cis-Permethrin in Flooded Soil: Report No. 9. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by U.S. Agricultural Research Service, Agricultural Environmental Quality Institute and Univ. of Maryland, Dept. of Botany, submitted by FMC Corp., Phila- delphia, PA; CDL:096695-N)

110637 Elliot, M.; Faanram, A.; Janer, N. ; et al. (1973) A phot ostable pyrethroid. Nature 248(Nov):169-170. (Also In unpublished submission received on unknown date under 279-EX-60; submitted by FMC Corp., Philadelphia, PA; CDL:226420-L)

110676 Cleverly, B.; Hill, I. (1977) Permethr in: The Degradation of the Pesticide in Flooded Soils Incubated under Laborator y Condi- tions: Report Series TMJ 1527B. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Imperial Chemical Indus- tries, Ltd., Eng., submitted by FMC Corp., Philadelphia, PA; CDL:096696-A)

40190101 Brown, P.; Leahey, J. (1987) Permethrin: Photolysis on a Soil Sur- face: Laboratory Project ID: RJ0581B. Unpublis hed study pre- pared by ICI Plant Protection Division. 53 p.

40201601 Brown, P.; Leahey, J. (1987) Supplement to MRID #40190101 (Missing Page): Permethrin: Photolysis on a Soil Su rface: Laboratory Project ID: RJ0581B. Unpublished study prepared by ICI Plant Protection Division. 3 p.

45369734 Burri, R. (1996) Photodegradation Study of (Inert Ingredient) on Soil: Lab Project Number: 370247: M9425. Unpublished study prepared by RCC Umweltchemie AG. 81 p.

92142049 Leahey, J. (1990) ICI Americas Inc. Phase 3 Summary of MRID 40190101 and Related MRIDs 00073990, 40201601. Permethrin: Photolysis on a Soil Surface and a Comparison of the Microflora a nd Physicochemical Properties of Soils Used in UK Laboratory Studies with Those of USA Soils: Report No. RJ0581B and RJ0429B; Study PP557AG01 and PP000CK10. Prepared by ICI AGROCHEMICAL. 15 p.

162-1 Aerobic soil metabolism

MRID Citation Reference

45538 Arnold, D.J.; Cleverley, B.A.; Hill, I.R. (1976) Permethrin: Labo- ratory Studies of the Degradation of the Pesticide in Soil: Report No. TMJ 1287 B. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by92 Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL: 096331-B)

45539 Arnold, D.J.; Cleverly, B.A.; Hill, I.R. (1977) Permethrin: The Degradation of the Pesticide in Soil under Laboratory Conditions, III: Report No. TMJ 1512 B. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096331-C)

45540 Arnold, D.J.; Cleverly, B.A.; Hill, I.R. (1976) Permethrin: Degra- dation in Soil under Laboratory Conditions (II): Report No. TMJ 1427 B. (Unpublished study received Aug 22, 1977 under 10182- EX-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Am ericas, Inc., Wilmington, Del.; CDL:096331-D)

110631 Arnold, D.; Cleverley, B.; Hill, I. (1976) Permethrin: Laboratory Studies of the Degradation of the Pesticide in Soil: Report Series TMJ 1287 B. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096695-K)

110632 Arnold, D.; Hill, I. (1977) Permethrin : Extraction and Identifi- cation of the Bound Residues of the Pesticide in Soil: Report Series 1513B. (Unpublished study received Feb 14, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096695-M)

110633 Kaufman, D.; Jordan, E.; Kayser, A. ; et al. (1977) Degradation of 14CCarbonyl Cis- and Trans-, and 14C-Met hylene cis-Permethrin in Flooded Soil: Report No. 9. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by U.S. Agricultural Research Service, Agricultural Environmental Quality Institute and Univ. of Maryland, Dept. of Botany, submitted by FMC Corp., Phila- delphia, PA; CDL:096695-N)

110636 Kaufman, D.; Jordan, E. (1976) Prelim inary Soil Metabolism Investi- gations with FMC-33297: Report No. 2. (Unpublished study re- ceived on unknown date under 279-EX-60; prepared by U.S. Dept. of Agriculture, Agricultural Environmental Quality Institute, Pesticide Degradation Laboratory in cooperation with Univ. of Maryland, Botany Dept., submitted by FMC Corp., Philadelphia, PA; CDL:226420-C)

110668 Kaufman, D.; Jordan, E.; Kayser, A.; et al. (1976) Permethrin Degradation in Soil and Microbial Cultures. (Unpub lished study received Jan 3, 1978 under 279-3013; prepared by U.S. Agricul- tura l Research Service, Agricultural Environmental Quality In- stitute an d Univ. of Maryland, Dept. of Botany, submitted by FMC Corp., Philadelphia, PA; CDL:096699-U)

110676 Cleverly, B.; Hill, I. (1977) Permethr in: The Degradation of the Pesticide in Flooded Soils Incubated under Laborator y Condi- tions: Report Series TMJ 1527B. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Imperial Chemical Indus- tries, Ltd., Eng., submitted by FMC Corp., Philadelphia, PA; CDL:096696-A)93 110677 Kaufman, D.; Barnett, E.; Jordan, E.; et al. (1977) Mi crobial Deg- radation of Permethrin: Report No. 10. (Unpublished study re- ceived Jan 3, 1978 under 279-3013; prepared by U.S. Agricultural Research Service, Agricultural Environmental Quality Institute and Univ. of Maryland, Dept. of Botany, submitted by FMC Corp., Philadelphia, PA; CDL:096696-B)

149594 Lord, K.; McKinley, M.; Walker, N. (1982) Degradation of permethrin in soils. Environmental Pollution A(29):81-90.

158880 Kaufman, D.; Jordan, E.; Kayser, A. (1977) Degradation of [Carbon 14]- Carbonyl-cis- and trans-Permethrin in soil: Report No. 6. Unpublished study prepared by US Agricultural Research Service, Agricultural Environmental Quality Institute and Univ. of Mary- land, Dept. of Botany. 31 p.

42004602 41970602 Hakins, B.; Kirkpatrick, D.; Shaw, D. ( 1991) The Effect of Applica- tion Rate and Soil Moisture Content on the Ra te of Degradation of ?Carbon 14| Permethrin in Aerobic Sandy Loam So il: Lab Pro- ject Number: HRC/ISN 247/91296. Unpublished study prepared by Huntingdon Research Centre, Ltd. 40 p.

42410002 Hawkins, D.; Kirkpatrick, D.; Shaw, D.; et al. (1992) The Aerobic Soil Metabolism of ?carbon 14|-Permethrin: Lab Project Number: HRC/ISN 251/911499. Unpublished study prepared by Huntingdon Research Centre, Ltd. 92 p.

45369735 Wyss-Benz, M.; Tschech, A. (1995) (I nert Ingredient): Degradation and Metabolism in One U.S. Soil Incubated Under Aerobic COnditions: Lab Project Number: 340334: M9421. Unpublished study prepared by RCC Umweltchemie AG. 81 p.

45369736 Fluckiger, J. (1995) (Ine rt Ingredient): Degradation in Three Soils Incubated Under Aerobic Conditions: Lab Pr oject Number: 340345: M9422. Unpublished study prepared by RCC Umweltchemie AG. 83 p.

162-2 Anaerobic soil metabolism

MRID Citation Reference

149594 Lord, K.; McKinley, M.; Walker, N. (1982) Degradation of permethrin in soils. Environmental Pollution A(29):81-90.

41970601 Hawkins, D.; Kirkpatrick, D.; Shaw, D.; et al. (1991) The Metaboli- sm of 14CPermethrin in Sandy Loam Soil Under Anaerobic Conditi- ons: Lab Project Number: HRC/ISN236/91107. Unpublishe d study prepared by Huntingdon Research Centre, Ltd. 75 p.

41970602 Hawkins, D.; Kirkpatrick, D.; Shaw , D.; et al. (1991) The Effects of Application Rate and Soil Moisture C ontent on the Rate of Degradation of ?14C|-Permethrin: Lab Project Nu mber: HRC/ISN247/ 91296. Unpublished94 study prepared by Huntingdon Research Centre Ltd. 40 p.

42004601 Hakins, B.; Kirkpatrick, D.; Shaw, D. (1991) The Metabolism of ?Carbon 14| Permethrin in Sandy Loam Soil under Anaerobic Condi- tions: Lab Project Number: HRC/ISN 236/91107. Unpublishe d study prepared by Huntingdon Research Centre, Ltd. 75 p. 162-3 Anaerobic aquatic metab.

MRID Citation Reference

43982001 Robinson, R. (1996) Anaerobic Aquatic Metabolism of (carbon 14)-Permethrin: Lab Project Number: XBL94091: RP T00252. Unpublished study prepared by Xenobiotic Labs, Inc. 225 p. 162-4 Aerobic aquatic metab.

MRID Citation Reference

43938201 Robinson, R.; Ryan, J. (1996) Aerobi c Aquatic Metabolism of (carbon 14)- Permethrin: Lab Project Number : XBL94092: RPT00220. Unpublished study prepared by XenoBiotic Labs, Inc. 220 p. 163-1 Leach/adsorp/desorption

MRID Citation Reference

42151 Clarke, G.E.; Morrod, R.S. (1977) PP 557: Adsorption of PP 557 and Its Hydrolysis Products, R 110074 and R 79406, by Soil: TMJ 1472B. (Unpublished study received Aug 22, 1977 under 10182-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096330-F)

42152 Prashad, S.; Stevens, J.E.; Newby, S. E. (1977) Permethrin: Mobility of Permethrin and its Degradation Pr oducts in Soil: AR 2716B. (Unpublished study received Aug 22, 1977 under 10182-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Amer i- cas, Inc., Wilmington, Del.; CDL:096330-G)

45541 Arnold, D.J.; Hill, I.R. (1977) Permethr in: Extraction and Identification of the Bound Residues of the Pesticide in Soil: Report No. TMJ 1518B. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., sub- mitted by ICI Americas, Inc., Wilmington, Del.; CDL:096331-E)

58861 Kaufman, D.D.; Russell, B.A.; Helling, C.S.; et al. (1978) Movement of Decamethrin, Cypermethrin, Permethrin and Their Degradation Products in Soil. (Unpublished study received Nov 13, 1980 under 8340-EX-6; prepared by U.S. Dept. of Agriculture, Agri- cultural Environmental Quality Institute,95 Pesticide Degradation Laboratory an d Univ. of Maryland, Botany Dept., submitted by American Hoechst Corp., Somerville, N.J.; CDL:099744-H)

90052 Prashad, S.; Stevens, J.E.; Newby, S. E. (1977) Permethrin: Mobility of Permethrin and Its Degradation Products in Soil: AR 2716B; 5B 1/3. (Unpublished study received Dec 30, 1981 under 10182-64; prepared by Imperial Chemical Industries Ltd., England, submit- ted by ICI Americas, Inc., Wilmington, Del.; CDL:070560-A)

90054 Clarke, G.E.; Morrod, R.S. (1977) PP 557: Adsorption of PP 557 and Its Hydrolysis Products, R 110074 and R 79406, by Soil: Report Series TMJ 1472B. (Unpublished study received Dec 30, 1981 un- der 10182-64; prepared by Imperial Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL: 070560-C)

93684 Brandau, E.G.; Goertler, M.G.; Otsa, H.L.; et al. (1975) Carbofuran, FMC 33297, FMC 25213 and Endosulfan Soil Adso rption/ Desorption Studies: M3785. (Unpublished study received Jan 8, 1982 under 279-2712; submitted by FMC Corp., Philadelphia, Pa.; CDL:246582-G)

97454 Williams, I.H.; Brown; M.J. (1979) Pers istence of permethrin and WL 43775 in soil. Journal of Agricultural and Food Chemistry 27(1):130-132. (Also~In~unpublished submission received Mar 17, 1982 under 59-200; submitted by Burroughs Wellcome Co., Re - search Triangle Park, N.C.; CDL:247048-B)

99038 Kaufman, D.D.; Russell, B.A.; Helling, C.S.; et al. (1981) Movement of cypermethrin, decamethrin, permethrin, a nd their degradation products in soil. Journal of Agricultural and Food Chemistry 29 (2):239-245. (Also~In~unpublished submission received Dec 30, 1981 under 10182-64; submitted by ICI Americas, Inc., Wilming- ton, Del.; CDL:070559-S)

102042 Brandau, E.; Goertler, M.; Robinson, R. (1975) Mobility of FMC 33297 in Soil: M-3703. (Unpublished study received Dec 1, 1976 under 7G1891; prepared by FMC, submitted by ICI United States, Inc., Wilmington, DE; CDL:096431-F)

110681 Brandau, E.; Goertler, M.; Robinson, R. (1975) Mobility of FMC 33297 in Soil: M-3703. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096696-G)

110682 Prashad, S.; Stevens, J.; Newby, S. ( 1977) Permethrin: Mobility of ... and Its Degradation Products in Soil: AR 2716B. (Unpub- lished study received Jan 3, 1978 under 279-3013; prepared by Imperial Chemical Industries, Ltd., Eng., submitted by FMC Corp., Philadelphia, PA; CDL:096696-H)

112937 Brandau, E.; Goertler, M.; Otsa, H. ; et al. (1975) Ca rbofuran, FMC 33297, FMC 25213 and Endosulfan Soil Adsorption/ Desorption Studies: Analytical Report M-3785. (Unpublished study r eceived Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadel- phia, PA; CDL:096699-T)96 129016 Kaneko, H.; Ohkawa, H.; Miyamoto, J. (1978) Degradation and move- ment of permethrin isomers in soil. J. Pestic ide Sci. 3:43-51. (A lso In unpublished submission received Jun 8, 1983 under 20954-EX-19; submitted by Zoecon Corp., Palo Alto, CA; CDL:250536-E)

41868001 Davis, M. (1991) Sorption/Desorption of ?Carbon 14| Permethrin on Soils by the Batch Equilibrium Method: Lab Project Number: SC900 199: 138E329OE1. Unpublished study prepared by Battelle Memori- al Institute. 98

p. 42196701 Cranor, W. (1991) Leaching Characterist ics of Soil Incorporated PermethrinFollowing Aerobic Aging: Lab Project Number: 39227: 138E3190E1: PC0162. Unpublished study prepared by ABC Labs., Inc. 183 p.

43424901 Gravelle, W. (1994) Adsorption/De sorption of (carbon 14)- mPBAcid and (carbon 14)-trans-DCVA on Four Soils : Lab Project Number: 138E2394E1: P2960. Unpublished study prepared by FMC Corp. 93 p.

45170102 Hurt, A.; Hand, L. (2000) Permethrin: Adsorption and Desorption Properties in Four Soils: Lab Project Number: 00JH005: RJ2978B. Unpublished study prepared by Zeneca Agrochemicals. 60 p.

45369733 Volkl, S.; Morgenroth, U. (1995) Adsorp tion/Desorption of (Inert Ingredients) on Four Soils: Lab Project Number: 340356: M9423. Unpublished study prepared by RCC Umweltchemie AG. 77 p.

164-1 Terrestrial field dissipation

MRID Citation Reference

45546 Ussary, J.P. (1977) Dissipation of Pe rmethrin in Soil, Champaign, Illinois: Report No. TMU0262/75B. (Unpublished study received Aug 22, 1977 under 10182-EX-3; submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096331-K)

65809 Ussary, J.P. (1981) Permethrin Residu es in Samples from a 1980 Ala- bama Runoff Study: Report Series TMUO540/B. (Unpublished study received Jan 15, 1981 under 279-3014; prepared by ICI Americas, Inc., submitted by FMC Corp., Philadelphia, Pa.; CDL:244090-B)

79260 ICI Americas, Incorporated (1981) ?P ermethrin Residue-- Soil and Cotton|. (Compilation; unpublished study received Jan 15, 1981 under 10182-18; CDL:245647-A)

102040 Leppert, B.; Chow, J.; Grana, B.; et al. (1976) Determination of FMC 33297 Insecticide Residues in Soil from Cotton Field Trials: W-0061. (Unpublished study received Dec 1, 1976 under 7G1891; prepared by FMC, submitted by ICI United States, Inc., Wil- mington, DE; CDL:096431-D)97 102041 Leppert, B.; Chow, J.; Grana, B.; et al. (1976) Determination of Dissipation Rate of FMC 33297 Residues in Soil: W-0065. (Un- published study received Dec 1, 1976 under 7G1891; prepared by FMC, submitted by ICI United States, Inc., Wilmington, DE; CDL:096431-E)

102101 Markle, J.; Allsup, T.; Fujie, G.; et al . (1976) Determination of FMC 33297 in Soil and Rotational Crop Samples: W- 0144. (Un- published study received Jan 27, 1978 under 10182-17; prepared by FMC, submitted by ICI Americas, Inc., Wilmington, DE; CDL: 096765-J)

110664 Union Carbide Corp. (1977) The Application of Two Permethrin Formulations on a Cotton Field Adjacent to an Aquatic Ecosystem: ?Submitter| ACT 060.81. (Unpublished study rece ived Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096699-N)

110665 U.S. Agricultural Research Service (1976) Synthetic Pyrethroid (FMC 33297) in Soil and in Surface Runoff from Cotton Plots, 1976. (Unpublished study; CDL:096699-P)

110683 Leppert, B.; Chow, J.; Grana, B.; et al. (1976) Determination of Dissipation Rate of FMC 33297 Residues in Soil: W-0065. (Unpub- lished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL:096696-K)

110684 Markle, J.; Kalb, E.; Fullmer, O. (1977) Dissipation of FMC 33297 Residues in Soil: W-0182. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL:096696-L)

110685 Leppert, B.; Grana, B.; Russell, K. ; et al. (1976) Dissipation of FMC 33297 Residues in Soils following Multiple Applications: W-0116. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL:096696-M)

110702 ICI United States, Inc. (1976) Ambus h Pyrethroid Ins ecticide: Residue Chemistry. (Unpublished study received Jan 17, 1977 under 10182-EX-6; CDL:230167-C)

155291 Stearns, J. (1985) Dissipation of C yperamide and m-Phenoxybenzalde- hyde Residues in Soil Treated with Ammo Insecticide: RAN-0149. Unpublished study prepared by FMC Corp. with review of previous- ly submitted soil studies appended. 39 p.

155793 Chapman, R.; Harris, C. (1981) Persisten ce of four pyrethroid insecticides in a mineral and an organic soil. J. E nviron. Sci. Health B16(5):605-615.

42359101 Becker, J. (1992) Pounce 3.2 EC Insec ticide--Terrestrial Field Dissipation: Lab Project Number: 138E4191R1. U npublished study prepared by FMC Corp. 180 p.

42394707 Eubanks, M. (1992) Ronilan Fungicide (BAS 352 12 F) Soil Dissipation in Orchard and Strawberry Use Patterns: Analysis through 360 Days: Lab Project98 Number: EP9001: 92-5093: ER92026. Unpub lished study prepared by Stewart Ag Research Services, Inc.; Morse Labs, Inc.; Horizon Labs, Inc. 856 p.

164-2 Aquatic field dissipation

MRID Citation Reference

44030501 Hatfield, M. (1996) Aquatic Dissipation of Permethrin in California and North Carolina: Interim Final Report: Lab Project Number: AA940907: 94-0024: P2703M. Unpublished study prepared by EN -CAS Analytical Laboratories and American Agricultural Services, Inc. 2044 p.

44157101 Hatfield, M. (1996) Addendum to A quatic Dissipation of Permethrin in California and North Carolina: MRID 44030501: Final Report: Lab Project Number: AA940907: 94-0024. Unpublished study prepared by EN-CAS Analytical Labs. and American Ag ricultural Services, Inc. 266 p.

65820 Hill, I.R.; Harvey, B.R.; Weissler, M. S. (1977) Permethrin: Degradation in River Sediments, River Water and in Flooded Soils: RJ0008 A. (Unpublished study received Dec 29, 1980 under 10182- EX-19; prepared by Imperial Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:244018-C)

164-3 Forest field dissipation

MRID Citation Reference

158536 Kingsbury, P. (1984) Environmental impact assessment of insecti- cides used in Canadian forests. P. 365-376 in Ch emical and Bio- logical Controls in Forestry, ACS Symposium Series No. 238, edited by W. Garner and J. Harvey. American Chemical Society.

165-0 Accumulation Studies -- General

MRID Citation Reference

32136 Kuc, W.J. (1980) Preliminary 14C-P ermethrin Model Aquatic Ecosystem Study: UCES Project No. 11507-62. (U npublished study received May 2, 1980 under 279-3014; prepared by Union Carbide Corp., submitted by FMC Corp., Philadelphia, Pa.; CDL:242372-A)

42169 Ells, S.J. (1977) Kinetics of Aged ^14IC-PP557 in a Model Aquatic Ecosystem. (Unpublished study received Aug 22, 1977 under 10182-3; prepared by EG&G, Bionomics, submitte d by ICI Americas, Inc., Wilmington, Del.; CDL:096330-Y)

65810 Vilkas, A.G.; Kuc, W.J. (1980) FM C Corporation (Carbon -14)-Permethrin99 Model Aquatic Ecosystem Study: UCCES Study 11507-98. (Unpublished study received Jan 15, 1981 under 279- 3014; prepared by Union Carbide Corp., submitted by FMC Corp., Philadelphia, Pa.; CDL:244090-C)

102097 Fujie, G.; Markle, J.; Gana, B. ( 1977) Determination of FMC 33297 Residues in Pond Study Samples from a FMC 33297 Cotton Environmental Impact Study: W-0204. (Unpublished study r eceived Jan 27, 1978 under 10182-17; submitted by ICI Americas, Inc., Wil- mington, DE; CDL:096765-B)

165-4 Bioaccumulation in fish

MRID Citation Reference

41300401 Burgess, D. (1989) Uptake, Depurati on and Bioconcentration of ?Carbon-14|- permethrin by Bluegill Sunfish (Lep omis macrochirus): ABC Lab Project Number PC-0117; FMC No.138E548 9E1; ABC Final Report 37676. Unpublished study prepared by Analyti- cal Bio-chemistry Laboratories, Inc. in cooperation with FMC Corp. 54 p.

41300402 Tullman, R. (1989) Accumulation Studies : Laboratory Stud ies of Pesticide Accumulation in Fish: Acid (Cyclopropyl )-?carbon-14| Labelled Permethrin in the Bluegill Sunfish: Lab Project Number P-2314; 138E5489E1-1. Unpublished study prepared by FMC Corp. in cooperat ion with Analytical Biochemistry Labora- tories, Inc. 96 p.

41300403 Singer, S. (1989) Accumulation Studie s: Laboratory Studies of Pesticide Accumulation in Fish: ?Car bon-14|-alcohol (Phenyl) Labe lled Permethrin in the Bluegill Sunfish: Lab Project Nu mber P-2262; 138E5489E1-2. Unpublished study prepared by FMC Corp. in cooperat ion with Analytical Biochemistry Laboratories, Inc. 83 p.

92142050 Czochor, L. (1990) ICI Americas Inc. Phase 3 Summary of MRID 41300401 and Related MRIDs 41300402, 41300403. Permet hrin (Pounce) Insecticide Bioaccumulation in Fish: Project I.D.: 135E5489E1, 138E5489E1-1, 138E5489E1-2. Prepared by FMC CORP. 20 p.

201-1 Droplet size spectrum

MRID Citation Reference

40954101 Lindsay, A. (1988) Droplet Size Sp ectrum. Mist Blower Applicator: Laboratory Study No. FORM-1. Unpublis hed study prepared by FMC Corp. 65 p.

45486202 Zhai, J.; Groome, M. (1995) Study to De termine the Spray Drift, Droplet Size Spectrum and Droplet Deposition of Aqua-Permanone: Lab Project Number: GD95-0031. Unpublished study prepared by Aventis Environmental Science USA LP. 120 p.100 45486203 Zhai, J. (1996) AquaPermanone Droplet Assessment with Common ULV Sprayers: Lab Project Number: 92034. Unpublished study prepared by Aventis Environmental Science USA LP. 8 p.

202-1 Drift field evaluation

MRID Citation Reference

41336401 Hall, F.; Downer, R. (1989) Permethrin: A Review of Permethrin Orchard Spray Data. Unpublished study prepared by Ohio State Univ., Laboratory for Pest Control Application Technology. 38 p.

43173801 Groome, J.; Mooney, M.; Bassler, M.; et al. (1992) Permanone 10 EC Spray Drift Study: Lab Project Number: HTRE/92/C1. Unpublished study prepared by Wellcome Berkhamsted, United Kingdo m Fairfield America Co. 137 p.

45486202 Zhai, J.; Groome, M. (1995) Study to De termine the Spray Drift, Droplet Size Spectrum and Droplet Deposition of Aqua-Permanone: Lab Project Number: GD95-0031. Unpublished study prepared by Aventis Environmental Science USA LP. 120 p.

Non Guideline 110698 ICI Americas, Inc. (1976) ?Environmen tal Effects of Ectiban Pyre- throid Insecticide 25% Wettable Powder|. (Com pilation; unpub- lished study received Feb 3, 1977 under 10182-EX-8; CDL: 228187-A)

110702 ICI United States, Inc. (1976) Ambus h Pyrethroid Inse cticide: Residue Chemistry. (Unpublished study received Jan 17, 1977 under 10182-EX-6; CDL:230167-C)

110702 ICI United States, Inc. (1976) Ambus h Pyrethroid Inse cticide: Residue Chemistry. (Unpublished study received Jan 17, 1977 under 10182-EX-6; CDL:230167-C)

137900 Hu, H; Weiner, P.; Ferraro, C. (197 5) Vapor Pressure of FMC 33297: Report No. CGP-75-14. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL: 096696-I)

110698 ICI Americas, Inc. (1976) ?Environmen tal Effects of Ectiban Pyre- throid Insecticide 25% Wettable Powder|. (C ompilation; unpublished study received Feb 3, 1977 under 10182-EX-8; CDL: 228187-A)

44396502 Travis, K. (1997) A Modified Tier II Aquatic Exposure Analysis of Cotton Pyrethroids, Incorporating Landscape-Le vel Exposure Factors: Lab Project Number: PYRETHROIDS\3. Unpublis hed study prepared by Zeneca Agrochemical (Zeneca Ltd). 221 p.101 44396504 Ritter, A.; Williams, W.; Cheplick, J. ( 1997) Tier 1 and Tier 2: Modeling of Pyrethroid Exposure to Aquatic Nontar get Organisms Associated with Use on Cotton: Lab Project Number: WEI 794.01: PWG. Unpublished study prepared by Waterborne Environmental, Inc. (WEI). 80 p.

47164602 Holmes, C.; Vamshi, R. (2007) Data and Methodology Used for Spatial Analysis of California Red Legged Frog Observations and Proximate Land Cover Characteristics. Project Number: 3152007, WEI/252/03. Unpublished study prepared by Waterborne Envi ronmental, Inc. (WEI). 19 p.

Permethrin Ecotoxicity Bibliography

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference

42119 Ross, D.B.; Cameron, D.M.; Roberts, N. L. (1976) The Acute Oral Tox- icity (LD^50I) of PP 557 (Permethrin) to Mallard Ducks: ICI 68/ WL/7639. (Unpublished study received Aug 22, 1977 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-B)

42120 Ross, D.B.; Cameron, D.M.; Roberts, N. L. (1976) The Acute Oral Tox- icity (LDI50^) of PP 557 (Permethrin) to Japanese Quail: ICI 68/ WL/7640. (Unpublished study received Aug 22, 1977 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-C)

42121 Ross, D.B.; Cameron, D.M.; Roberts, N. L. (1977) The Acute Oral Tox- icity (LDI50^) of PP 557 (Permethrin) to the Pheasant: ICI 68 WL/77154. (Unpublished study received Aug 22, 1977 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-E)

42142 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1977) The Acute Oral Toxicity (LD^50I) of PP 557 (Permethrin) to the Mallard Duck According to E.P.A. Guidelines: ICI 68 WL/77205. (Unpublis hed study received Aug 22, 1977 under 10182-EX-3; prepared by Hunt- ingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-AE)

42143 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1977) The Acute Oral Toxicity (LD^50I) of PP 557 (Permethrin) to the Japanese Quail According to E.P.A. Guidelines: ICI 68 WL/77207. (Unpublis hed study received Aug 22, 1977 under 10182-EX-3; prepared by Hunt- ingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-AF)

42144 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1977) The Acute Oral Toxicity (LDI50^) of PP 557 (Permethrin) to the Starling: ICI/68 WL/76499.102 (Unpublished study received Aug 22, 1977 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-AG)

42145 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1977) The Acute Oral Toxicity (LDI50^) of PP 557 (Permethrin) to the Ring-Necked Phe- asant According to E.P.A. Guidelines: ICI 68 WL/ 77207. (Unpub- lished study received Aug 29, 1977 under 1082-EX-3; prepared by Huntingdon Research Center, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325- AH)

72844 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1976) The Acute Oral Toxicity (LDI50^) of PP 557 (Permethrin) to Starlings: ICI 68/ WL/7637. (Unpublished study received Dec 2, 1976 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:095995-B)

73686 Fink, R. (1975) Final Report: Acute Or al LD^50~--Mallard Duck: ProjectNo. 104-115. (Unpublished study received on unknown date under 279-EX60; prepared by Truslow Farms, Inc., submitted by FMC Corp., Philadelphia, Pa.; CDL:226419-X)

110669 FMC Corp. (1976) Wildlife Toxicol ogy Studies: ?FMC 33297|. Summary of studies 096699-W through 096699-AA. (U npublished study re- ceived Jan 3, 1978 under 279-3013; CDL:096699-V)

112938 Fink, R. (1975) Acute Oral LD50--M allard Duck: FMC 33297: Project No. 104-115; NCT 601.62. Final rept. (Unpublis hed study re- ceived Jan 3, 1978 under 279-3013; prepared by Truslow Farms, Inc., submitted by FMC Corp., Philadelphia, PA; CDL:096699-W)

157306 ICI United States, Inc. (1976) [Acute Oral Toxicity to Rats Using PP557]. Unpublished study. 8 p.

41888401 Hakin, B.; Rodgers, M.; Dawe, I. (1991) Permethrin: Acute Oral Tox- icity (LD50) to Mallard Duck: Lab Project Number: ISN 244/91362. Unpublished study prepared by Huntingdon Research Centre, Ltd. 29 p.

45369711 Grau, R. (1994) (Inert Ingredient) Acut e Oral Toxicity to Bobwhite Quail: Lab Project Number: VB-024: E 2920732. Unpublished study prepared by Bayer AG. 37 p.

71-2 Avian Dietary Toxicity

MRID Citation Reference

42122 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1976) The Subacute Toxic- ity (LDI50^) of PP 557 (Permethrin) to Mallard Ducks: ICI 68 WL/ 75837. (Unpublished study received Aug 22, 1977 under 10182-EX- 3; prepared by103 Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-F)

42123 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1976) The Subacute Toxic- ity (LDI50^) of PP 557 (Permethrin) to Japanese Quail: ICI 68/ WL/7638. (Unpublished study received Aug 22, 1977 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-G)

43733 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1976) The Subacute Toxicity (LCI50^) of PP 557 (Permethrin) to Pheasants: ICI/68WL/ 75839. (Unpublished study received Dec 2, 1976 under 10182- EX-3; prepared by Huntingdon Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:095995-D)

43734 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1976) The Subacute Tox- icity (LCI50^) of PP 557 (Permethrin) to Adult Starlings: ICI68/ WL/7636. (Unpublished study received Dec 2, 1976 under 10182- EX-3; prepared by Huntington Research Centre, England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:095995-E)

72845 Fink, R. (1975) Final Report: Eight-Day Dietary LCI50^--Bobwhite Quail: Project No. 104-113. (Unpublished study received Dec 2, 1976 under 10182- EX-3; prepared by Truslow Farms, Inc., submit- ted by ICI Americas, Inc., Wilmington, Del.; CDL:095995-C)

83717 Fink, R. (1975) Final Report: Eight-D ay Dietary LCI50^--Mallard Duck: Project No. 104-114. (Unpublished study received on un- known date under 279-EX-60; prepared by Truslow Fa rms, Inc., submitted by FMC Corp., Philadelphia, Pa.; CDL:226419-Y)

88741 Fink, R. (1975) Final Report: Eight-Day Dietary LCI50^--Bobwhite Quail: Project No. 104-113. (Unpublished study received on unknown date under 279-EX-60; prepared by Truslow Fa rms, Inc., submitted by FMC Corp., Philadelphia, Pa.; CDL:226419-Z)

112939 Fink, R. (1975) Eight-day Dietary LC50--Mallard Duck: FMC 33297: Project No. 104-114; NCT 600.62. Final rept. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Truslow Farms, Inc., submitted by FMC Corp., Philadelphia, PA; CDL: 096699-X)

112940 Fink, R. (1975) Eight-day Dietary LC50--Bobwhite Quail: FMC 33297: Project No. 104-113; NCT 600.62. Final rept. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Truslow Farms, Inc., submitted by FMC Corp., Philadelphia, PA; CDL: 096699-Y)

41888402 Hakin, B.; Rodgers, M.; Dawe, I.; et al . (1991) Permethrin: Subacute Dietary Toxicity (LC50) to Bobwhite Qu ail: Lab Project Number : ISN245/91262.104 Unpublished study prepared by Hunti ngdon Research Centre, Ltd. 29 p.

41888403 Hakin, B.; Rodgers, M.; Dawe, I.; et al. (1991) Permethrin: Subacu| te Dietary Toxicity (LC50) to Ma llard Duck: Lab Project Number: ISN246/912632. Unpublished study prep ared by Huntingdon Research Centre, Ltd. 29 p. 71-4 Avian Reproduction

MRID Citation Reference

42124 Fink, R. (1976) Final Report: One Ge neration Reproduction Study-- Mallard Duck: Project No. 123-113. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Wildlife Inte rnation- al, Ltd., submitted by ICI Americas, Inc., Wilmingt on, Del.; CDL:096325-J)

42125 Or 110671 Fink, R. (1976) Final Report: One-Gene ration Reproduction Study-- Bobwhite Quail: Project No. 123-112. (Unpublished study re- ceived Aug 22, 1977 under 10182-EX-3; prepared by Wildlife In- ternational, Ltd., submitted by ICI Americas, Inc., Wilmingt on, Del.; CDL:096325-K)

110669 FMC Corp. (1976) Wildlife Toxicol ogy Studies: ?FMC 33297|. Summary of studies 096699-W through 096699-AA. (U npublished study re- ceived Jan 3, 1978 under 279-3013; CDL:096699-V)

110670 Fink, R. (1976) One-generation Reproduc tion Study--Mallard Duck: PP 557: Project No. 123-113; ACT 125.71. Final rept . (Unpub- lished study received Jan 3, 1978 under 279-3013; prepared by Wildlife International Ltd., submitted by FMC Corp., Philadel- phia, PA; CDL:096699-Z)

110671 Fink, R. (1976) One-generation Repr oduction Study--Bobwhite Quail: PP 557: Project No. 123-112; ACT 125.71. Final rept . (Unpub- lished study received Jan 3, 1978 under 279-3013; prepared by Wildlife International Ltd., submitted by FMC Corp., Philadel- phia, PA; CDL:096699-AA)

42322901 Beavers, J.; Foster, J.; Lynn, S.; et al. (1992) Permethrin: A One-Generation Study with the Northern Bobwhite (Coli nus virginianus): Lab Project Number 104-166: A90-3330. Unpublished study pr epared by Wildlife Intl. 157 p.

42322902 Beavers, J.; Foster, J.; Lynn, S.; et al. (1992) Permethrin: A One-Generation Reproduction Study with the Mallard (Anas platyrhynchus ): Lab Project Number 104-167: A90-3328. Unpublished study pr epared by Wildlife Intl. 161 p.

72-1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

43263 LeBlanc, G.A.; Sousa, J.; Sleight, B.H., III. (1979) Acute Toxicity of FMC 33297 to Bluegill (Lepomis macroc hirus): Re- port # BW-79-12-582.105 (Unpublished study received Jul 24, 1980 under 279-3013; prepared by EG&G, Bionomics, submitted by FMC Corp., Philadelphia, Pa.; CDL:242902-A)

43265 LeBlanc, G.A.; Sousa, J.; Sleight, B.H., III. (1979) Acute Tox- icity of FMC 33297 to Rainbow Trout (Salmo gairdneri): Re- port # BW-79-12-584. (Unpublished study received Jul 24, 1980 under 2789-3013; prepared by EG&G, Bionomics, submitted by FMC Corp., Philadelphia, Pa.; CDL:242902-C)

65816 Hill, R.W.; Young, B.E. (1978) The Acut e Toxicity of Permethrin Acid and 3-Phenoxy Benzyl Alcohol to Rainbow Trout (Salmo gairdneri): BL/B/1918. (Unpublished study received Dec 29, 1980 under 10182-EX-19; prepared by Imperial Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:244017-J)

97444 Maddock, B.G. (1978) Determination of the Acute Toxicity of Compound 212 (WRL) to Bluegill Sunfish (Lepom is macrochirus) Using Dimethyl Sulphoxide as the Solvent: Doc. No. HEFG 28- 13. (Unpublished study received Mar 17, 1982 under 59-200; pr e- pared by Wellcome Foundation Ltd., England, submitted by Burroughs Wellcome Co., Research Triangle Park, N.C.; CDL: 247045-A)

97445 Maddock, B.G. (1978) Determination of the Acute Toxicity of 21Z (WRL) to Bluegill Sunfish (?~Lepomis macroc hirus~?) Using Ace- tone as the Solvent: Doc. No. HEFG 78-17. (Unpublished study received Mar 17, 1982 under 59-2; prepared by Wellcome F ounda- tion Ltd., England, submitted by Burroughs Wellcome Co., Research Tr iangle Park, N.C.; CDL:247045-B)

97446 Maddock, B.G. (1978) Determination of the Acute Toxicity of Compound 21Z (WRL) to Rainbow Trout (Sal mo gairdneri) Using Di- Methyl Sulphoxide as the Solvent: Doc. N o. HEFG 78-11. (Un- published study received Mar 17, 1982 under 59-200; pr epared by Wellcome Foundation Ltd., England, submitted by Burroughs Wellcome Co., Research Triangle Park, N.C.; CDL:247045-C)

97447 Maddock, B.G. (1978) Determination of the Acute Toxicity of Com- pound 21Z (WRL) to Rainbow Trout (?~Salmo gairdneri~?) Using Ac- etone as the Solvent: Doc. No. HEFG 78-12. (Unpublished study received Mar 17, 1982 under 59-200; prepared by Wellcome Founda- tion Ltd., England, submitted by Burroughs Wellcome Co., Re- search Triangle Park, N.C.; CDL:247045- D)

110657 or 73687 Bentley, R. (1974) Acute Toxicity of FMC-33297 Technical to Blue- gill (Lepomis macrochirus) and Rainbow Trout (Salmo gairdneri): (Submitter) NCT 551.61. (Unpublished study rece ived Jan 3, 1978 under 279-3013; prepared by Bionomics, EG & G Envi ronmental Consultants, submitted by FMC Corp., Philadelphia, PA; CDL: 096699-B)

110663 Union Carbide Corp. (1976) Acute Toxicity of FMC 33297 to Bluegill106 Sunfish, Lepomis macrochirus Rafine sque and the Water Flea, Daphnia magna Straus: (Submitter) ACT 29.11, .12. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL:096699-J)

110705 Hill, R.; Maddock, B.; Hart, B.; et al. (1977) Acute Toxicity of JFU 5054 to Bluegill Sunfish ...: BL/B/1832. (Unpublished study received Nov 30, 1977 under 10182-EX-7; prepared by Imperial Chemical Industries, Ltd., Eng., submitted by ICI Americas, Inc., Wilmington, DE; CDL:232533-A)

110706 ICI Americas, Inc. (1977) Summary: ?Environmental Data on PP 557|. (Compilation; unpublished study received Oct 25, 1977 under 10182-EX-7; CDL:233029-A)

141977 Coulon, D. (1982) Toxicity of Ambu sh and Pydrin to Red Crawfish, Procambarus clarkii (Girard) and Ch annel Catfish, Icta luras pun- ctatus rafinesque in Laborator y and Field Studies and the Accum- ulation and Dissipation of Associated Residues. Unpublished dissertation study prepared by Louisiana State Univ. 56 p.

155779 Kumaraguru, A.; Beamish, F. (1981) Leth al toxicity of permethrin (NRDC143) to rainbow trout, Salmo gairdneri, in relation to body weight and water temperature. Water Research 15:503-505.

155781 Holcombe, G.; Phipps, G.; Tanner, D. (1982) The acute toxicity of kelthane, dursban, disulfoton, pydrin, and permethrin to fathead minnows Pimephales promelas and rainbow trout Salmo gairdneri. Environmental Pollution 29:167-178.

41068002 Coats, J.; O'Donnell-Jeffery, N. (1979) Toxicity of four s ynthetic pyrethroid insecticides to rainbow trout. Bulletin of Enviro- mental Contamination and Toxicology 23:250-255.

41068003 McLeese, D.; Metcalfe, C.; Zitko, V. (1980) Lethality of permethrin, cypermethrin and fenvalerate to sa lmon, lobster and shrimp. Bulletin of Environmental Contaminati on and Toxicology 25:950-955.

00110705 Adams, D. (1990): Permethrin (PF557): Determination of a 24% w/w Formulation to Bluegill Sunfish (L epomis macrochirus): Lab Project Number: BL/B/1832. Unpublished study prepared by ICI Brixham Lab. 11 p.

42584003 Sankey, S.; Morris, D.; Caunter, J. et al. (1992) Permethrin: Acute Toxicity to Rainbow Trout of a 10% EC Fo rmulation: Lab Project Number: BL4529/B. Unpublished study prepared by ICI, PLC. 21 p.

42584004 Sankey, S.; Morris, D.; Caunter, J.; et al. (1992) Permethrin: Acute Toxicity to Bluegill Sunfish of a 10% EC Formulation: Lab Project Number:107 BL4570/B. Unpublished study prepared by ICI, PLC. 21 p.

43740601 Kent, S.; Morris, D.; Caunter, J. et al . (1995) Permethrin: Acute Toxicity to Rainbow Trout (Oncorhynchus mykiss) of a 2 lb./gallon (25%) Formulation: Fish Toxicity in Rainbow Trout ( TEP): Lab Project Number: BL5427/B: AB0015/A. Unpublished study prepared by Brixham Environmental Lab. 24

p.
110663 Union Carbide Corp. (1976) Acute Toxicity of FMC 33297 to Bluegill Sunfish, Lepomis macrochirus Rafine sque and the Water Flea, Daphnia magna Straus: (Submitter) ACT 29.11, .12. (Unpublished study received Jan 3, 1978 under 279-3013; submitted by FMC Corp., Philadelphia, PA; CDL:096699-J)

42126 Hill, R.W.; Maddock, B.G.; Hart, B. (1976) Determination of the Acute Toxicity of PP557 to Rainbow Tr out (Salmo gairdnerii): BL/B/1700. Includes undated method entitled: Determination of low levels of PP557 in water samples from fish bioassay te sts. (Unpublished study received Aug 22, 1977 under 10182-EX-3; pre- pared by Imperi al Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-L)

42127 Hill, R.W.; Maddock, B.G.; Hart, B.; et al. (1976) Determination of Acute Toxicity of PP557 to Brook Trout (? ~Salvelinus fonti?~- ?~nalis?~): BL/B/1712. Includes undated method entitled: Deter- mination of low levels of PP557 in water samples from fish bio- assay tests. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., sub- mitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-M)

42128 Hill, R.W.; Maddock, B.G.; Hart, B. (1976) Determination of the Acute Toxicity of PP 557 to Bluegill Sunfis h (?~Lepomis macro?- ?~chirus~?): BL/B/1701. Includes undated method entitle d: De- termination of low levels of PP 557 in water samples from fi sh bioassay tests. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., sub- mitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-P)

42129 Hill, R.W.; Maddock, B.G.; Hart, B.; et al. (1976) Determination of the Acute Toxicity of PP 557 to Fathead Minnow (?~Pimephales ?~promelas~?): Report BL/B/1726. Includes undated method en- titled: Determination of low levels of PP 557 in water samples fr om fish bioassay tests. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL: 096325-R)

42130 Hill, R.W.; Maddock, B.G.; Hart, B.; et al. (1976) Determination of the Acute Toxicity of PP 557 to Mirror Carp (?~Cyprinus car~?- ?~pio~?): BL/B/1715. Includes undated method entitled: Determi- nation of low levels of PP 557 in water samples from fish bio- assay tests. (Unpublished study108 received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Inc., sub- mitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-S)

42132 Hill, R.W.; Maddock, B.G.; Hart, B.; et al. (1977) Determination of the Acute Toxicity of Formulation JF U 5054 to Rainbow Trout (?~Salmo gairdnerii~?): BL/B/1798. Includes undated method en- titled: Determination of low levels of JFU 5054 in water samples from fish bioassay tests. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL: 096325-U)

42133 Hill, R.W.; Maddock, B.G.; Hart, B.; et al. (1977) Determination of the Acute Toxicity of Formulation JFU 5054 to Bluegill Sunfish (?~Lepomis macrochirus?~): BL/B/1799. Includes undated method entitled: The determination of low levels of JFU 5054 in water samples from fish bioassay tests. (Unpublished study rece ived Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical In- dustries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-V)

43735 Buccafusco, R.J. (1976) Acute Toxic ity of PP-557 Technical to Channel Catfish (?~Ictalurus punctatus~?). (Unpublished study received Dec 2, 1976 under 10182-EX-3; prepared by EG&G, Bio- nomics, submitted by ICI Americas, Inc., Wilmingt on, Del.; CDL:095995-H)

72846 Buccafusco, R.J. (1976) Acute Toxi city of PP-557 Technical to Coho Salmon (~Oncorhynchus kisutch~). (Unpublished study received Dec 2, 1976 under 10182-EX-3; prepared by EG&G, Bionomics, sub- mitted by ICI Americas, Inc., Wilmingt on, Del.; CDL:095995-G)

73685 Bentley, R.E. (1974) Acute Toxicity of FMC-33297 Technical to Blue- gill (~Lepomis macrochirus~) and Rainbow Trout (~Salmo~ ?~gairdneri~). (Unpublished study received on unknown date under 279-EX-60; prepared by Bionomics, EG&G Environmental Consultants, submitted by FMC Corp., Philadelphia, Pa.; CDL: 226419-W)

73687 Bentley, R.E. (1975) Acute Toxici ty of FMC-33297 3.2 EC to Bluegill (Lepomis macrochirus) and Rainbow Trout (Salmo gairdneri). (Unpublished study received on unknown date under 279-EX-60; prepared by EG&G, Bionomics, submitted by FMC Corp., Ph iladel- phia, Pa.; CDL:226419-AA)

83085 Buccafusco, R.J. (1976) Acute Toxic ity of PP-557 Technical to Atlantic Salmon (~Salmo salar~). (Unpublished study received Dec 2, 1976 under 10182-EX-3; prepared by EG&G, Bionomics, sub- mitted by ICI Americas, Inc., Wilmington, Del.; CDL:095995-F)

72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference109 43267 Surprenant, D.C. (1979) Acute Toxi city of FMC 33297 to the Water Flea (?~Daphnia magna~?): Report # BW-79-12-574. (Unpublished study received Jul 24, 1980 under 279-3013; prepared by EG&G, Bionomics, submitted by FMC Corp., Philadelphia, Pa.; CDL: 242902-E)

65817 Getty, C.; Wilkinson, W.; Davies, P.J.; et al. (1978) Permethrin Acid and 3- Phenoxybenzyl Alcohol: Toxicity to First Instar Daphnia magna: Report Series RJ 0042B. (Unpublished st udy received Dec 29, 1980 under 10182- EX-19; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmingt on, Del.; CDL:244017-K)

97448 Maddock, B.G. (1979) Determination of the Acute Toxicity of WRL 21Z to the Freshwater Shrimp (Gammarus pul ex) Using Acetone as the Solvent: Doc. No. HEFG 79-4. (Unpublished study received Mar 17, 1982 under 59- 200; prepared by Wellcome Founda tion Ltd., England, submitted by Burroughs Wellcome Co., Research Tr iangle Park, N.C.; CDL:247045-E)

97449 Thompson, R.S.; Williams, T.D. (1978) Determination of the Acute Toxicity of Compound 21Z (WRL) to Daphnia ma gna Using Acetone as the Solvent: Doc. No. HEFG 78-10. (Unpublished study re- ceived Mar 17, 1982 under 59-200; prepared by Wellcome Founda- tion Ltd., England, submitted by Burroughs Wellcome Co., Re- search Triangle Park, N.C.; CDL:247045-F)

110658 or 43736 Bentley, R. (1975) Acute Toxicity of FMC-33297 Technical to Water Flea (Daphnia magna): ?Submitter| NCT 624.61. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by EG & G, Bionomics, submitted by FMC Corp., Philadelphia, PA; CDL: 096699-D)

110659 Bentley, R. (1975) Acute Toxicity of FMC-33297 3.2 EC to Water Flea (Daphnia magna): ?Submitter| NCT 623.61. (Unpublished study re- ceived Jan 3, 1978 under 279-3013; prepared by EG & G, Bio- nomics, submitted by FMC Corp., Philadelphia, PA; CDL:096699-E)

141970 Anderson, R. (1982) Toxicity of Fenvale rate and permethrin to sev- eral nontarget aquatic invertebrates. En vironmental Entomology. 11(6): 1251- 1257.

152736 Getty, C.; Wilkinson, W. (1978) PP557: Ecological Effects on Three Ponds, U.K. 1976-77. Observations on Inverteb rates and Amphibia up to 1 Year after Treatment: Repor t No. RJ0041B. Unpublished study prepared by Imperial Chemical Industries PLC. 21 p.

42584002 Kent, S.; Sankey, S.; Grinell, A. (1992) Permethrin: Acute Toxicity to Daphnia magna of a 10% EC Formulat ion: Lab Project Number: BL4530/B. Unpublished study prepared by ICI, PLC. 19 p.

43740602 Kent, S.; Morris, D.; Banner, A. et al . (1995) Permethrin: Acute Toxicity to Daphnia magna of a 2 lb/gallon (25%) Fo rmulation: Invertebrate Toxicity--110 Freshwater LC50 (TEP): Lab Pr oject Number: BL5382/B: AB0015/B: AG240. Unpublished study prepared by Br ixham Environmental Lab. 21 p.

42136 Buccafusco, R.J. (1977) Acute Toxicity of Permethrin Technical (PP 557) to Crayfish (?~Procambarus blandingi?~). (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by EG&G, Bionomics, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-Y)

42137 Doma, S.; Evered, P. (1976) PP 557: Acute Toxicity and Reproduction Studies on First Instar and Ephippi a of~Daphnia magna?~: Report SeriesTMJ 1455B. (Unpublished study received Aug 22, 1977 un- der 10182-EX3; submitted by ICI Americas, Inc ., Wilmington, Del.; CDL:096325-Z)

42138 Doma, S.; Evered, P. (1976)~Daphni a magna?~: Determination of Acute Toxicity of Pesticides: TMJ 1405A . (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperi al Chemical In- dustries, Ltd., submitted by ICI Americas, Inc.; Wilmington, Del.; CDL:096325-AA)

42139 Evered, P.; Doma, S. (1977) PP 557: Acute Toxicity of Emulsifiable Concentrate (JFU 5054) to First Inst ar~Daphnia magna?~: Report SeriesTMJ 1504 B. (Unpublished study received Aug 22, 1977 un- der 10182-EX3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmingt on, Del.; CDL: 096325-AB)

42141 Doma, S. (1976) PP557: Acute Toxi city and Reproduction Studies on the Large Pond Snail,?~Limnaea stagnalis?~: Report Series TMJ 1395B. (Unpublished study received Aug 22, 1976 under 10182- EX-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; CDL:096325-AD)

43736 Bentley, R.E. (1975) Acute Toxicity of FMC-33297 Technical to Water Flea (?~Daphnia magna~?): NCT 624.61. (U npublished study received Dec 2, 1976 under 10182-EX-3; prepared by EG&G , Bio- nomics, submitted by ICI Americas, Inc., Wilmin gton, Del.; CDL:095995-I)

47039 Forbis, A.D.; McAllister, W.A.; Th ompson, C.M.; et al. (1980) Chronic Toxicity of ^14IC-Permethrin to ~Daphnia magna~under Flow-Through Test Conditions: Chronic Toxicity Fi nal Report # 23647. (Unpublished study including letters dated Apr 25, 1979 from M.J. Jaber to William A. McAllister; Jan 14, 1980 from A.D. Forb is to Mark Jaber; Sep 9, 1980 from A.D. Forbis to Mark Jab- er, received Oct 10, 1980 under 279-3014; prepared by Analytical Bio Chemistry Laboratories, Inc., submitted by FMC Corp., Phila- delphia, Pa.; CDL:243505-A)

47040 Forbis, A.D.; McAllister, W.A.; Thom pson, C.M.; et al. (1980) Dy- namic Acute Toxicity of ^14IC-Permethrin to Mayfly Nymphs (~Hexagenia bilineata~) in a Flow-Through Dilute r System: Fi- nal Report No. 23648. (Unpublished study including le tters dated Oct 30, 1979 from M.J. Jaber to William McAllister; Dec 4, 1979 from A.D. Forbis to Mark Jaber; Dec 12, 1979 from M.J. Jaber to Alan Forbis, received Oct 10, 1980 under 279-3014;111 pre- pared by Analytical Bio chemistry Laboratories, Inc., submitted by FMC Corp., Philadelphia, Pa.; CDL:243505-B)

72-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

110660 Heitmuller, T. (1975) Acute Toxici ty of FMC 33297 Technical (95.7%) to Eastern Oysters (Crassostrea virgini ca), Pink Shrimp (Penaeus duorarum), and Fiddler Crabs (Uca pugilator) : ?Submitter| NCT 619.61. (Unpublished study received Jan 3, 1978 under 279- 3013; prepared by Bionomics, EG & G, Inc., submitted by FMC Corp., Philadelphia, PA; CDL:096699-F)

110661 Heitmuller, T. (1975) Acute Toxici ty of FMC 33297 3.2 EC to Eastern Oysters (Crassostrea virginica), Pi nk Shrimp (Penaeus duorarum), and Fiddler Crabs (Uca pugilator): (Submitter) NCT 620.61. (Unpublished study received Jan 3, 1978 under 279- 3013; prepared by Bionomics, EG & G, Inc., submitted by FMC Corp., Philadel- phia, PA; CDL:096699-G)

141967 Borthwick, P.; Walsh, G. (1981) Ini tial Toxicological Assessment of Ambush, Bolero, Bux, Dushan, Fentrifa nil, Larvin, and Pydrin: Static Acute Toxicity Tests with Selected Es tuarine Algae, In- vertebrates, and Fish: EPA-600/4-81-076. Unpublished st udy pre- pared by Environmental Protection Agency, Environmenta l Research Laboratory. 9 p.

155767 Zitko, V.; Carson, W.; Metcalffe, C. (1977) Toxicity of pyrethroids to juvenile Atlantic salmon. Bull. E nviron. Contam. Toxicol. 18:35-41.

155788 Zitko, V.; McLeese, W.; Metcalfe, C. (1979) Toxicity of permethrin, decamethrin, and related pyrethroids to salmon and lobster. Bull. Environm. Contam. Toxicol. 21:338-343.

41134801 Ward, G.; Rabe, B. (1989) Acute Toxi city of Permethrin Technical to Inland Silversides (Menidia beryll ina) under Flow-through Con- ditions: Laboratory Project ID No. 93008- 0200-2130. FMC Corp. Study No. A88- 2747. Unpublished study prepared by Hunter/ESE Inc. 55 p.

41874901 Ward, G.; Rabe, B. (1989) Acute Toxi city of Permethrin Technical to Inland Silversides (Menidia beryll ina) Under Flow-through Condi- tions: Lab Project Number: 93008/0200/2130. Unpublished study prepared by Hunter/ESE, Inc. 55 p.

42584001 Kent, S.; Williams, T.; Sankey, S.; et al. (1992) Permethrin: Acute Toxicity to Mysid Shrimp of a 10% EC Formulation: Lab Project Number: BL4566/B. Unpublished study prepared by ICI, PLC. 18 p.

42608201 Sankey, S.; Morris, D.; Caunter, J. ; et al. (1992) Permethrin: Acute Toxicity to Sheepshead Minnow (C yprinodon variegatus) of a 10% EC112 Formulation: Lab Project Numb er: W420/D (FT31/91): BL4564/B. Unpublished study prepared by Imperial Chemical Industries, PLC. 18 p.

42723301 Thompson, R.; Sankey, S. (1992) Permet hrin: Acute Toxicity of a 10% EC Formulation to Larvae of the Pacifi c Oyster (Crassostrea gigas): Lab Project Number: BL4689/B. Unpublishe d study prepared by Zeneca, Ltd. 19 p.

42795101 Sankey, S.; Kent, S.; Holland, M. et al . (1993) Permethrin: Acute Toxicity to Sheepshead Minnow (Cyprinodon vari egatus) of a 2EC Formulation: Lab Project Number: BL4748/B: FT15/ 92. Unpublished study prepared by Brixham Environmental Lab. 16 p.

43394601 Sankey, S. (1994) Addendum to MRID 42608201-Permethrin: Acute Toxicity to Sheepshead Minnow (C yprinodon variegatus) of 10% EC formulation: Response to EPA EEB/ EFED Review: Lab Project Number: BL/4564/B/ADDENDUM. Unpublished study prepared by Brixham Environmental Lab. 9 p.

43394602 Sankey, S. (1994) Addendum to MRID 42795101-Permethrin: Acute Toxicity to Sheepshead Minnow (Cyprinodon variegatus) of a 2EC formulation: Response to EPA EEB/ EFED Review: Lab Project Number: BL/4748/B/ADDENDUM. Unpublished study prepared by Brixham Environmental Lab. 17 p.

43492901 Sankey, S. (1994) Addendum to MRID 42584001: Permethrin: Acute Toxicity to Mysid Shrimp (Mysidop sis bahia) of a 10 (percent) EC Formulation: Response to EPA EEB/ EFED Review: Lab Project Number: BL4566/B: BL4566/B ADDENDUM. Unpublished study prepared by Brixham Environmental Lab. 16 p.

43492902 Thompson, R. (1986) Supplemental Data in Support of MRID 42584001: Permethrin: Determination of Ac ute Toxicity to Mysid Shrimps (Mysidopsis bahia): Lab Project Number: BL/B/2921. Unpublished study prepared by Brixham En vironmental Lab. 16 p.

42135 Heitmuller, T. (1977) Acute Toxicity of PP557 to Brown Shrimp (Penqeus aztecus) and Fiddler Crabs (Uca pugila tor). (Unpub- lished study received Aug 22, 1977 under 10182-EX-3; prepared by EG&G, Bionomics, submitted by ICI Americas, Inc., Wil- mington, Del.; CDL:096325-X)

42140 Thompson, R.S.; Hill, R.W.; Cornish, S.K. (1977) Investigation of the Acute Toxicity of PP 557 to the Paci fic Oyster (Crassostrea gigas?): BL/B/1796. Includes undated method enti tled: The determination of low levels of PP 557 in seawater sample s from bioassay tests. (Unpublished study received Aug 22, 1977 under 10182-EX-3; prepared by Imperial Chemical Industries, Ltd., submitted by ICI America, Inc., Wilmington, Del.; CDL: 096325-AC)

72-4 Fish Early Life Stage/A quatic Invertebrate Life Cycle Study113 MRID Citation Reference

110662 Doma, S.; Evered, P.; Sealey, C. (1977) PP557: Acute Toxicity and Reproduction Studies on First Instar and Ephippia of Daphnia magna: TMJ 1455B. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Imperial Chemical Industries, Ltd., submitted by FMC Corp., Philadelphia, PA; CDL:096699-H)

141967 Borthwick, P.; Walsh, G. (1981) Ini tial Toxicological Assessment of Ambush, Bolero, Bux, Dushan, Fentrifanil, Larvin, and Pydrin: Static Acute Toxicity Tests with Selected Estuarine Algae, In- vertebrates, and Fish: EPA-600/4-81-076. Unpublished study pre- pared by Environmental Protection Agency, Environmenta l Research Laboratory. 9 p.

40102001 Thompson, R. (1986) Permethrin: Determination of Chronic Toxicity to Mysid Shrimps (Mysidopsis bahia) : Laboratory Project ID: BL/B/2965. Unpublished study prepared by Imperial Chemical Industries PLC. 24 p.

41068007 Hansen, D.; Goodman, L.; Moore, J.; et al. (1983) Effects of the synthetic pyrethroid AC 222, 705, permethrin a nd fenvalerate on sheepshead minnows in early life stage toxicity tests. En viron- mental Toxicology and Chemistry 2:251-258.

41068008 Spehar, R.; Tanner, D.; Nordling, B. (1983) Toxicity of the synthe- tic pyrethroids, permethrin and AC 222, 705 and their accumula- tion in early life stages of fathead minnows and sn ails. Aqua- tic Toxicology 3:171-182.

41315701 Thompson, R.; Williams, T.; Tapp, J. (1989) Permethrin: Determination of Chronic Toxicity to Mysid Shrimps (M ysidopsis bahia) (R un 2): Lab Project Number BL/B/3574; FT84/88; Stud y No. S259/A. Unpublished study prepared by Imperial Chemical Industr ies PLC, Brixham Laboratory. 44 p.

43745701 Kent, S.; Williams, N.; Gillings, E. ; et al. (1995) Permethrin: Chronic Toxicity to Daphnia magna: Lab Pr oject Number: BL5443/B. Unpublished study prepared by Zeneca Bri xham Environmental Lab. 51 p.

92142020 Swigert, J. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00047039. Carbon 14-Permethrin - Determination of the Chronic Toxicity to Daphnia magna:Report No. 23647. Prepared by ANALYTICAL BIO-CHEMISTRY LABS. INC. 13 p.

92142021 Hill, R. (1990) ICI Americas Inc. Phase 3 Summary of MRID 41315701 and Related MRIDs 40102001. Permethrin: Determination of the Chronic Toxicity of Active Ingredient to Mysi d Shrimp (Mysidopsis bahia) (Run 2): Report No. BL/B/3574; Study No. S259/ A. Prepared by ICI Brixham Lab. 10 p.

92142136 Smyth, D. (1990) ICI Americas Inc. Phase 3 Summary of MRID 40102001 and Related MRIDs 41315701. Permethrin: Determination of the Chronic114 Toxicity of Active Ingredient to Mysi d Shrimp (Mysidopsis bahia) (Run 1): Report No. BL/B/2965; Study No. P131/C. Prepared by ICI Brixham Lab. 17

p.
102096 E G & G Bionomics (1977) Chronic T oxicity of FMC 33297 to the Fat- head Minnow (Pimephales promelas): ACT 092.72. (Unpublished study received Jan 27, 1978 under 10182-17; submitted by ICI Americas, Inc., Wilmington, DE; CDL:096764-C)

110662 Doma, S.; Evered, P.; Sealey, C. (1977) PP557: Acute Toxicity and Reproduction Studies on First Instar and Ephippia of Daphnia magna: TMJ 1455B. (Unpublished study received Jan 3, 1978 under 279-3013; prepared by Imperial Chemical Industries, Ltd., submitted by FMC Corp., Philadelphia, PA; CDL:096699-H)

72-5 Life cycle fish

MRID Citation Reference

161436 Smith, W. (1986) Letter sent to R. St ewart dated July 17,1986: Pounce data callin fish life-cycle study. Pr epared by FMC Corp. 243 p.

ACC 263993 FMC Corp., 1986, Egg to Egg Fulll Life-cycle

72-7 Simulated or Actual Field Testing

MRID Citation Reference

Cella, G.E. (1980) Final Report, Pote ntial Aquatic Ecological Ef- fects of Aerial Applications of Two Permet hrin Formulations on Cotton: UCCES Study 11507-36. (Unpublished study received Oct 10, 1980 under 279-3014; prepared by Union Carbide Corp., E nvi- ronmental Services, submitted by FMC Corp., Philadelphia, Pa.; CDL:243505-C)

Union Carbide Corporation (1980) Pote ntial Aquatic Ecological Effects of Aerial Applications of Two Permet hrin Formulations on Cotton: UCCES Study 11507-36; A-80-474. Final rept. (U n- published study received May 8, 1981 under 279-EX-79; submitted by FM C Corp., Philadelphia, Pa.; CDL:245051-P)

92142023 Hamer, M. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00042134 and Related MRIDs 00102097. The App lication of Two Permethrin Formulations on a Cotton Field Adjacent to an Aquatic Ecosystem. Prepared by UNION CARBIDE CORP. ENVIR. SER. 13 p.

141-1 Honey bee acute contact115 MRID Citation Reference

149694 Gary, N.; Westerdahl, B. (1983) Effect s of Three Synthetic Pyre- throids on Honey Bees (Apis mellifera L.): Final Report. Un- published study prepared by Univ. of California--Davis , Dept. of Entomology. 66 p.

41047801 Rothpletz, G. (1977) Ambush: Bee T oxicity Study in Alfalfa (Washington): Laboratory Project ID TMUD1796/B. Unpublished study prepared by ICI Americas, Inc. 6 p.

42674501 Gough, H.; Jackson, D.; Lewis, G. ( 1993) Permethrin: Acute Contact and Oral Toxicity to Honey Bees (Apis mellifera) of Technical Material: Lab Project Number: 92JH166: RJ1344B. Unpublished study prepared by ICI Agrochemicals. 27 p.

45044 Clark, A.M. (1976) Permethrin: Oral and Contact Toxicity to Honey- bees of Technical Material and an Encap sulated Emulsion: TMJ 1273 A. (Unpublished study received Dec 20, 1976 under 100- EX-53; prepared by Plant Protection, Ltd., submitted by Ciba- Geigy Corp., Greensboro, N.C.; CDL:095990-B)

45045 Stanford, R.L.; Atkins, E.L. (1976) La boratory Studies of Various Pesticides on Honeybees: Report No. 22CA75-013. (Unpublished study received Dec 20, 1976 under 100-EX-53; prepared by ICI United States, Inc., submitted by Ciba-Geigy Corp., Greens boro, N.C.; CDL:095990-C)

45046 Johansen, C.; Mayer, D.; Madse n, R.; et al. (1975) Bee Research Investigations, 1975. (Unpublished st udy received Dec 20, 1976 under 100- EX-53; prepared by Washington State Univ., submitted by Ciba-Geigy Corp., Greensboro, N.C.; CDL:095990-E)

102103 Smailes, J.; Wilkinson, W. (1977) Permethrin: Toxicity to Honey- bees ... on Oilseed Rape: Report Series TMJ 15 78B. (Unpublished study received Jan 27, 1978 under 10182-17; prepared by Imperi al Chemical Industries, Ltd., Eng., submitted by ICI Americas, Inc ., Wilmington, DE; CDL:096765-M)

141-2 Honey bee residue on foliage

MRID Citation Reference

42009301 Lynn, S.; Hoxter, K. (1991) Permet hrin Wettable Powder-Ambush 25 W: A Foliage Residue Toxicity Study with the Honey Bee: Lab Project Number: WIL 123-165. Unpublished study prepared by Wildlife Inte rnational Ltd. 28

p.

142-3 Simulated or Actual Field Testing116 MRID Citation Reference

9042 Burkhardt, C.C.; Puterka, G.J.; Michels, G.J., Jr. (1977) Impact of Insecticides on Beneficial Insects in an Experimental Plot Used to Control Alfalfa Weevil, Lygus Bugs, and Pea Aphids on Alfalfa. (Unpublished study received Oct 12, 1978 under 352- 342; prepared by Univ. of Wyoming, Agricultural Substation, sub- mitted by E.I. du Pont de Nemours & Co., Wilmington, Del.; CDL: 236883-C)

43717 Smith, F.D. (1976) PP557: Effects on Predatory and Parasitic Arthropods: Report Series TMJ 1283 B. (Unpublished study re- ceived Dec 2, 1976 under 10182-EX-3; prepared by Imperial Chemi- cal Industries, Ltd., submitted by ICI Americas, Inc., Wilming- ton, Del.; CDL:095996-G)

77052 Atkins, L. (1981) Field Trials on Co tton and Alfalfa and Foliage Residue Trials To Assess Toxicity to H oneybees: Mavrik 2E. Fi- nal rept. (Unpublished study received May 13, 1981 under 20954- EX-18; prepared by Univ. of California--Riverside , Dept. of Entomology, submitted by Zoecon Corp., Palo Alto, Calif.; CDL: 070100-L)

102105 Smailes, J.; Wilkinson, W. (1977) Permethrin: Toxicity to Honey- bees ... on Top Fruit: Report Series TMJ 1577B. (Unpublished study received Jan 27, 1978 under 10182-17; prepared by Imperial Chemical Industries, Ltd., Eng., ICI Americas, Inc., Wilmington, DE; CDL:096765-O)

127368 Harris, C.; Turnbull, S. (1978) Laborat ory studies on the contact toxicity and activity in soil of four pyrethroid in secticides. Canadian Entomologist 110(Mar):285-288. (Submitter AW-81-0099; also In unpublished submission received Apr 8, 1983 under 39398- 16; submitted by Sumitomo Chemical America, Inc., New Yo rk, NY; CDL:249939-B)

5008360 Hoy, M.A.; Flaherty, D.; Peacock, W.; Culver, D. (1979) Vineyard and laboratory evaluations of methomyl, di methoate, and permethrin for a grape pest management program in the San Jo aquin Valley of California. Journal of Economic Entomology 72(2):250-255.117 Appendix A. PRD Data Re quest Justification Tables

The following proposed Data Call-In tables include rationales for requiring the data requested in this problem formulation, explanations of the ut ility of the data, and explanations for how the data might impact risk assessment, following the format provided by PRD.

Guideline Number: Non-guideline Study Title: Leachability from Treated Wood Rationale for Requiring the Data A study is required for certain chemicals that are employed to treat wood and that are used outdoors. It should be conducted acco rding to the American Wood Preservers Association Standard Method of Determini ng the Leachability of Wood Preservatives (E11-06). It is suggested that the registrant provide a prot ocol to be evaluated by the Agency prior to performing the study. Practical Utility of the Data
How will the data be used? Permethrin is a synthetic pyrethroid with high toxicity towards aquatic organisms, including those living in the benthos. It is used for wood protection treatment to forest products and building/ products outdoors. The results of this study w ill be used in the ecological risk characterization, and in particular, for aquatic assessments. At the present time, based on the binding capaci ty of this chemical to so il organic carbon, and its high octanol/ water partition coefficient, EFED be lieves that permethrin binds strongly to the wood material to which it is applied, but there are uncertainti es as to the degree to which this occurs. Knowledge of the leachability from treated wood for this chemical is important.

In addition, the data will be used to derive the equivalent application ra te to be used in the aquatic models GENEEC2 and PRZM/ EXAMS. The results from these models are used for exposure assessment ( i.e. , to derive estimated environm ental exposure concentrations or EECs), ecological risk estimation, and ultimately in risk assessment.

How could the data impact the Agency’s future decision-making? Without these data, the Agency would have to make certain conservative assumptions ( e.g. , assume that 100% of the permethrin l eaches instantly from the treated wood, to estimate the equivalent application rate in GENEEC and PRZM/ EXAMS). These conservative assumptions could lead to higher predicted environmental exposure concentrations (EECs), according to the models , and consequently, higher risk quotients. The application rate input para meter has a major effect in the determination of the aquatic EECs and RQs. Also, there would be a hi gher degree of uncerta inty in the overall transport assessment for ecological effects. Knowledge of the leachability from treated wood of this chemical in detail is essentia l to perform a better and accurate environmental fate/ transport and risk assessment.118 Guideline Number: Non-guideline Study Title: Leachability from Treated Wood The lack of these data will limit the flexibi lity the Agency and registrants have in coming into compliance with the Endangered Species Ac t and could result in use restrictions for this chemical that may be unnecessary.

Guideline Number: Non-guideline Study Title: POTW Treatability Study Rationale for Requiring the Data POTW Treatability Study – The Agency has recently requested and provided comments on a protocol developed by the Py rethroid Working Group (PWG) for a bench scale study of waste water treatment, to assess the percentage removed in the biosolids by the treatment, the amount that would degrad e during treatment, and the amount that would remain in the waste water. Thes e data would be used to inform removal percentages by waste water treatment, whic h is an input to the Exposure and Fate Assessment Screening Tool’s (E-FAST) “dow n-the-drain” module. The Office of Pesticide Programs will continue to confer with the Office of Water with the goal of refining our down-the-drain assessment for regist ration review. It is the responsibility of the registrant to ensure that permethrin is included in the study completed by the PWG or conduct a similar study on its own (following submission of a protocol for review).

Practical Utility of the Data
How will the data be used? These data would be used to inform rem oval percentages by waste water treatment, which is an input to the E xposure and Fate Assessment Screening Tool’s (E-FAST) “down-the-drain” module. This model wi ll yield aquatic estimated environmental exposure concentrations (EECs), which will be used to derive risk quotients (RQs); the results of the model are used in the ecological risk assessment of permethrin.

How could the data impact the Agency’s future decision-making? Without these data, the Agency will have to make assumptions regarding the level of removal of permethrin ( e.g. , use modeling results from EPIWEB v.4.0). These assumptions are likely to be crude and conserva tive. The lack of these data will limit the flexibility the Agency and registrants ha ve in coming into compliance with the Endangered Species Act, and could result in use restrictions for permethrin which may otherwise be avoided, or whic h are unnecessarily severe.119 Guideline Numbers and Study Titles:

 Test Method 100.4 (OCSPP 850.1770, in prep .); Whole sediment: chronic invertebrates freshwater ( Hyalella azteca )

 Test Method 100.5 (OCSPP 850.1760, in prep .); Whole sediment: chronic invertebrates freshwater ( Chironomus dilutus ) US EPA 2001,

 EPA 600/R-01/020 (OCSPP 850.1780, in prep .); Whole sediment: chronic invertebrates marine ( Leptocheirus plumulosus )

Rationale for Requiring the Data No chronic sediment toxicity tests for fres hwater or marine inve rtebrates have been submitted to satisfy the Agency’s updated data requirements for outdoor uses in 40 CFR Part 158 (October 26, 2007). For permethrin, av ailable information indicates that benthic organisms may be exposed via run-off or spra y drift applications used in agricultural, forest, and residential settings. Based on calculations in the most recent EFED assessment for permethrin where estimated se diment concentrations were calculated, the peak sediment porewater EECs predicted fo r permethrin ranged from 0.00364 ppm for barrier treatment to 1.62 ppb for nursery-pin e seed orchard-high rate (US EPA 2008a). The upper end of this range exceeds 0.1 of the most sensitive acute LC/EC 50 (0.0212 μg a.i./L for the amphipod Hyallela azteca ), which satisfies one of the criteria for requiring chronic whole sediment toxicity testi ng under 40 CFR Part 158. Chronic reproductive effects were also seen in other aquatic inve rtebrate taxa (daphnids and mysids), although at higher levels than acute effects were observed for amphipods.

Permethrin has a long expected half-life in sediment, based on submitted soil metabolism and aquatic metabolism studies (aerobic soil , 37 days; anaerobic so il, 204 days; aerobic aquatic metabolism, 38.2-42.9 days; anaerob ic aquatic metabolism, 113-175 days) (MRIDs 42410002, 41970601, 43938201 and 43982001). These half-life values are substantially greater than 40 CFR Part 158 criterion of 10 days. The potential for persistent exposure from permethrin in se diment is also indicated by open literature studies on pyrethroids (Weston et al., 2004; Holmes et al., 2008; Weston and Lydy, 2010; Lao et al., 2010; Ding et al ., 2009).

The third set of trigger criteria for requiring chronic testing (K d > 50 or log K OW >3 or
K OC > 1000) is also met for permethrin (K d ranges from 140-401, log K OW is 6.1, and
K OC values range from 19,300 to 60,900). The physicochemical property triggers (K d , K OW and K OC ) reflect the propensity of the chemical to partition onto the particulate or organic matter phases of sediments. Exceed ing any one of the physicochemical property triggers listed above is sufficient for indicati ng the pesticide has reasonable potential for partitioning to the sediment compartment.

For sediment studies involving pyrethr oids, chronic whole sediment tests on Hyalella

azteca , Chironomus tentans , and Leptocheirus plumulosus are requested. Although both are freshwater species, Hyalella and Chironomus differ substantially in their ecological niche ( i.e. , epibenthic v. infaunal species), phy siology. Evidence in open literature suggests that Hyalella azteca is among the most sensitive aquatic invertebrates to permethrin based on acute water column te sts (Weston and Lydy, 2010; Brander et al.,120 2009). Permethrin has the potential to ente r estuarine/marine water bodies based on current usuage patterns that include coastal ar eas. Therefore, testi ng is also required for an estuarine/marine sediment-d welling invertebrate species.

Until the final OCSPP guidelines for chronic se diment toxicity tests are published, the registrant should submit a protocol to EFED for approval prior to test initiation.

 Test Method 100.4: Hyalella azteca 42-d Test for Measuring the Effects of Sediment Associated Contaminants on Survival, Growth, and Reproduction in USEPA 2000 Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invert ebrates EPA 600/R99/064 ( OCSPP 850.1770, in prep. );

 Test Method 100.5: Life-cycle Test fo r Measuring the Effects of Sedimentassociated Contaminants on Chironomus dilutus (formerly known as C. tentans ) in USEPA 2000 Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invert ebrates EPA 600/R99/064 ( OCSPP 850.1760, in prep. ); and

 Leptocheirus plumulosus in USEPA 2001 Method for Assessing the Chronic Toxicity of Marine and Estuarine Sedi ment-associated Contaminants with the Amphipod Leptocheirus plumulosus EPA 600/R-01/020 ( OCSPP 850.1780, in

prep. ).

Practical Utility of the Data

How will the data be used? Data from sediment toxicity studies will be used to estimate potential risks to benthic organisms associated with uses of permet hrin. The data will reduce uncertainties associated with the current risk assessme nt for benthic species and will improve our understanding of the potential effects of permethrin.

How could the data impact the Agency’s future decision-making? Although there was uncertainty in estimating the effect of permethrin on benthic organisms in previous assessments, there was a potential risk associated with adverse effects identified for other aquatic organisms. Acceptable data for benthic organisms will reduce the uncertainty from the previous assessmen t If the data indicates that registered permethrin usage may pose a risk of adve rse effects to non-tar get benthic organisms above the Agency Level of Concern, the Agency may explore decision options to mitigate this risk. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance w ith the Endangered Species Act, and could result in use restrictions which may otherwise be avoide d, or which are unnecessarily

severe.121 Appendix B. Summaries of the Reported Permethrin Ecological Incidents in the EIIS Database

Table D-1. Permethrin Incident Reports Involving Aquatic Organisms

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description
I001849-002 Unknown fish Highly probable Registered

use A commercial pesticide applicator treated a building with permethrin. The next night, a heavy rain caused runoff of permethrin to a nearby private pond, killing approximately 300 fish. Louisiana, 4/6/1994. I016338-006 Bullhead ( Ameiurus sp.), flathead minnow ( Pimephales promelas ), and rainbow trout ( Onchorhynchus mykiss ) Highly probable Registered

use Multiple buildings were sprayed with permethrin and bifenthrin, with around 100 gallons of pesticides used combined. After application, a storm carried the pesticides to a nearby holding pond and killed hundreds of bullheads, flathead minnows, and rainbow trout. The pond water contained 0.098 - 3.40 ppb bifenthrin and 99.8 ppb permethrin. Trout fillets contained 34.4 ppb bifenthrin and 406 ppb permethrin. New York, 5/2/2005. I005761-001 Unknown fish Highly probable Unknown A rancher sprayed 120 cattle with permethrin and removed the livestock from the vicinity of the nearby pond for several hours. After the cattle returned to the pond, an undetermined number of fish died. Iowa, 8/5/1997. I001849-003 Unknown fish Highly probable Registered

use Permethrin and terbufos were applied to approximately 3,769 acres of corn fields, prior to planting. Heavy storms during the next month created heavy runoff and subsequent death of an estimated 1386 fish. The LSU School of Veterinary Medicine attributed the fishkill to both permethrin and terbufos (no data shown). Louisiana, 4/12/1994. I004374-003 Catfish (Ictaluridae) and sunfish (Centrarchidae) Highly probable Accidental misuse A fishkill occurred after a home was treated with permethrin. The pesticide equipment was rinsed in a manner that resulted in runoff to a nearby pond. Rain occurring after the treatment also contributed to runoff. Thousands of catfish and sunfish were killed. Missouri, 6/10/1995. I003402-005 Crayfish (Decapoda) Highly probable Registered

use Permethrin was applied to a residence for termite control. A heavy rain washed the pesticide into a stream, and thousands of dead crayfish were found 1-1.5 miles downstream. Soil samples taken underneath the house contained 46.0 ppm permethrin and122 Table D-1. Permethrin Incident Reports Involving Aquatic Organisms

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description
soil near the drainpipe contained 0.554 ppm permethrin. Permethrin was not detected in water samples, but sampling did not occur until two days after the incident. Virginia, 11/14/1995. I003653-001 Bass (Centrarchidae spp.), carp ( Cyprinus carpio ) and

catfish (Ictaluridae spp.) Highly probable Registered

use The basement floor and walls of a home were treated with permethrin to control for termites. A snowstorm occurred after the treatment, and the following snowmelt washed the pesticide into a nearby lake. Tissue samples for bass, carp and catfish contained 3.27, 3.7 and 3.7 ppm permethrin, respectively. Pennsylvania, 3/3/1996. I004439-038 Unknown fish Highly probable Accidental misuse A fishkill of unknown magnitude occurred in a backyard pond, after the lawn was treated with permethrin. Massachusetts, 6/20/1996. I009136-001 Crayfish (Decapoda) Highly probable Registered

use Heavy rains carried permethrin from a residence to a nearby stream. Dead crayfish were found one-third of a mile away from the home. Soil samples contained 10.0 ppb permethrin, while water samples had no detectable levels of the pesticide. Virginia, 4/13/1998. I006022-001 Rockfish ( Sebastes sp.) Probable Accidental misuse A state mosquito control truck sprayed permethrin within 10 feet of a commercial fish pond, killing 3000 rockfish. Maryland, 6/16/1997. I000598-022 Black bullhead catfish ( Ictalurus melas ) and

bluegill ( Lepomis

macrochirus ) Probable Accidental misuse After aerial spraying of permethrin in a nearby cornfield, an estimated 500 fish were killed in a nearby pond. Ten days after the accident occurred, samples were taken from the water, soil and sediment of the pond. Residues were below detection levels. Nebraska, 7/5/1992. I000124-014 Bluegill ( Lepomis macrochirus ) Probable Accidental misuse Treatment of home with permethrin entered house sump pump and emptied into fish pond, killing an unknown number of bluegill. Illinois, 3/31/1992. I001028-010 Unknown fish Probable Registered

use During a light rain, a home and outside deck were treated with permethrin. The runoff drained into a nearby canal, where dead fish were later discovered. The species and number of fish killed were not reported. Florida, 8/1/1993. I006261-001 Crayfish (Decapoda) and Probable Accidental After permethrin termiticide123 Table D-1. Permethrin Incident Reports Involving Aquatic Organisms

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description

rainbow trout ( Onchorhynchus mykiss ) misuse application to a home, around 230 dead crayfish and 50 dead rainbow trout were reported in a creek 160 feet away from the residence. Soil samples indicated permethrin levels between 17.0 – 53.0 ppb. Virginia, 4/16/1997. I007226-001 Bass (Centrarchidae sp.) and bream Probable Registered

use Permethrin was applied within the city limits of Greenville, Mississippi for vector control. Three days after the application, fifteen bass and two bream were found dead in a lake. Mississippi, 9/2/1998. I003582-010 Unknown fish Probable Unknown An unknown number of fish were killed as a result of permethrin contamination in a stream. Pennsylvania, 3/5/1996. I003582-042 Unknown fish Probable Unknown Runoff from permethrin treatment spray killed fish in a downhill pond. Indiana, 5/6/1996. I004439-039 Unknown fish Probable Registered

use A home was treated for termites with permethrin, and a fishkill of unknown magnitude occurred in a pond 20 feet away. Tennessee, 6/21/1996. I014689-015 Bluegill ( Lepomis macrochirus ) and catfish (Ictaluridae) Probable Misuse Permethrin was applied 400 feet away from a pond. Eight bluegill and seventy-two catfish were found dead. No further information on treatment site or method of application. Indiana, 5/7/2003. I003826-030 Unknown fish Possible Registered

use A fish kill occurred in a commercial fish pond. The owner attributed the problem to pesticide drift from nearby corn and soybean fields. After conducting tests for a range of pesticides, the NC Department of Agriculture stated that pesticides could not be determined as the cause of the fish kill. However, permethrin was found in the soil (0.41 ppm) and vegetation (1.4 ppm) of the area. Total magnitude of the fish kill was not reported. North Carolina, 6/14/1994.
B000175- 001 Unknown fish Possible Registered

use Three pesticides (paraquat, permethrin and bicep) and fertilizer were applied to a corn field. A fishkill in a nearby pond occurred after a heavy storm. The incident was attributed to the fertilizer and low dissolved oxygen, but permethrin may be another contributing factor due to its high toxicity to fish. Kentucky, 1992. I004439-121 Unknown fish Possible Unknown A lawn was treated with permethrin. After an unspecified time, an124 Table D-1. Permethrin Incident Reports Involving Aquatic Organisms

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description

unknown number of fish located in a nearby pond died. New Jersey, 9/9/1996. I004439-119 Unknown fish Possible Unknown A home exterior, 210 feet from a pond, was treated with permethrin. Four days later, a fish kill was observed. Virginia, 9/21/1996. I007984-003 Striped bass ( Morone saxatilis) , crayfish (Decapoda) and unknown frogs Possible Accidental misuse An employee of the Mosquito Control section of the Maryland Department of Agriculture applied permethrin to a residential property. One day later, 600 fish, crayfish and frogs were found dead. The spraying was 74 feet away from the pond, while regulations require 100 feet. Pond water sampled a few days after the incident showed low dissolved oxygen. Maryland, 6/16/1997. I014312-001 Goldfish ( Carassius

auratus ) Possible Registered

use Permethrin was applied to a lawn, and runoff caused by rains resulted in an estimated 40 – 60 goldfish deaths in a proximate pond. Kansas, 4/1/2003.
I008293-001 Velvet swords ( Xiphophorus helleri ), oscars ( Astronotus ocellatus) and discus (Symphysodon sp.) Possible Registered

use Drift from four pesticides (including permethrin) applied to tomato fields may have caused a fishkill in ponds 100 yards away. The species include several ornamental fish, including velvet swords, oscars, and discus. The applicator was observed lifting booms at row ends without ceasing spray flow. Oily residue was found at pond edges, and the ponds contained low dissolved oxygen. Dying fish exhibited tremors symptomatic of pyrethroid or organophosphate exposure. Florida, 12/1/1998.

Table D-2. Permethrin Incident Report s Involving Terrestrial Plant Species

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description
I007340-620 Unknown edible crop Possible Unknown Damage occurred to an edible crop as a result of permethrin use. Florida, 4/22/1998. I010927-003 Alfalfa ( Medicago sativa) Possible Registered

use An alfalfa field had been previously treated with permethrin and chlorpyrifos, and damaged occurred due to carryover. Both pesticides are believed to have contributed to the damage. Wisconsin, 4/15/1999. I012515-002 Unknown tropical plants Possible Unknown Tropical plants were treated with permethrin and piperonyl butoxide.125 Table D-2. Permethrin Incident Report s Involving Terrestrial Plant Species

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description
Plants exhibited burn spots, yellowing leaves and defoliation. Plants may have been suffering from nutrient deficiency, which may have compromised the waxy cuticle and made the plants more vulnerable to exposure. Unknown location, 8/13/2001. I019442-001 Clover (Trifolium sp.), timothy-grass ( Phleum
pretense ) and unknown

grasses and legumes Possible Intentional misuse Pesticide application to a right-of-way possibly caused chlorosis as far as 200 feet away in an adjacent hay and pasture field. Pesticides involved include permethrin, 2,4-D, acetochlor, atrazine, glyphosate, metribuzin and clomazone. Plant tissue samples from the right-of-way contained 9.85 ppm of Pendimethalin. None of the aforementioned chemicals were detected in samples from the hay and pasture field. The observed whitening of the vegetation is symptomatic of clomazone damage, but other herbicides present may have contributed. Ohio, 7/19/2007. I009544-001 Soybean ( Glycine max ) Possible Unknown A farmer attributes the reduced productivity of 142 acres of soybeans to permethrin and carboxin application. The pesticides are believed to have killed the Rhizobium bacteria in the soil inoculate added at the time of planting. The soybeans showed stunted growth and a light yellow color indicative of nitrogen deficiency. Wisconsin, 7/10/1999. I015105-005 Unknown nursery trees, ornamentals and birds Possible Unknown Drift from permethrin, atrazine, glyphosate and S-metolachlor caused the deaths of three birds and damage to trees and ornamentals in a nursery. The report did not specify which active ingredient may have caused the damage. Tennessee, 4/27/2004.

I016138-001 Cauliflower ( Brassica oleracea ) Unlikely Registered

use Aerial spraying of pesticides damages 70 acres of cauliflower, to the extent that the crop is claimed to be unfit for human consumption. Owner of field claims that the mixture of insecticides used was “contaminated and adulterated with herbicides”. Pesticides involved126 include permethrin, indoxacarb and imazethapyr. Imazethapyr is toxic to cauliflower and not registered for use on this crop, but no evidence was presented to show that the herbicide was actually sprayed in this instance. California, 10/11/2004. I000340-007 Unknown lawn plants Unlikely Unknown Permethrin was applied near a residence, and browning of lawn plants was reported. However, permethrin is not known to cause plant damage, and it is unlikely to be the cause of the observed browning. Florida, 10/7/1992.

Table D-3. Permethrin Incident Report s Involving Terrestrial Animal Species

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description
I011527-001 Monarch butterfly ( Danaus plexippus ) and unknown butterfly (Lepidoptera) Highly probable Registered

use A municipality was sprayed with permethrin and piperonyl butoxide. Several hours after application, residents began noticing hundreds to thousands of dead butterflies (mostly monarch). Analysis showed 20 – 37 ppm permethrin in butterfly samples. Minnesota, 8/23/2000. I003826-028 Bee (Apidae) Highly probable Accidental misuse Bee keepers report bee kills in hives and attribute the damage to aerial application of pesticide to a nearby soybean field. A certified aerial applicator treated 400 acres of soybean fields. Permethrin was found in nearby vegetation samples in concentrations ranging from 0.32 – 4.1 ppb. The applicator paid an $1800 fine to the North Carolina Department of Agriculture for misuse. North Carolina, 8/30/1994. I020998-040 Bee (Apidae) Highly probable Intentional misuse The Washington State Department of Agriculture reports that bee mortality occurred, caused by permethrin. Beekeepers suspect that the hives were deliberately sprayed to kill bees. No residue data was available. Washington, 6/20/2003. I004852-015 Parakeet (Psittacidae) Possibl e Unknown A residen ce was treated with permethrin and four days later, four parakeets died. No analytical evidence was reported. Oklahoma, 10/29/1996. I000340-006 Dog ( Canis Familiaris ) Possible Unknown A dog was treated with permethrin and cypermethrin. The dog then became ill127 Table D-3. Permethrin Incident Report s Involving Terrestrial Animal Species

Incident # Organism(s) Affected Certainty of
Involvement Legality of
Use Description
and incapacitated. Both pyrethroids are known toxicants to animals. New York, 12/3/1992. I016728-007 Unknown butterfly (Lepidoptera) Probable Unknown Pinellas County Mosquito Control received a report of one to two dozen commercially-raised butterflies following community-wide spraying with Biomist 31+66 ULV with active ingredients permethrin and piperonyl butoxide. Adult and caterpillar mortality occurred in a colony maintained by a local butterfly hobbyist. Florida, 4/1/2005.

I012515-004 Bee (Apidae) Possible Unknown Apiary damage possibly caused by permethrin and piperonyl butoxide. No information available on method of application or suspected misuse. Mississippi, 5/9/2001. I015105-005 Unknown nursery trees, ornamentals and birds Possible Unknown Drift from permethrin, atrazine, glyphosate and S-metolachlor caused the deaths of three birds and damage to trees and ornamentals in a nursery. The report did not specify which active ingredient may have caused the damage. Tennessee, 4/27/2004.