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### MGK Comments on the Preliminary Work Plan

MGK Comment: Page 5, Ecological Risk, with respect to pyrethrins in the environment, they

are one of the shortest-lived activ e ingredients, with half lives on the order of hours rather than days. Further, with respect to the CBD lawsuit, we believe that ecologi cal risk assessments on pyrethrins will not trigger levels of concern in the environment.

EFED Response: EFED acknowledges pyrethrins appear to be labile to certain routes of degradation/ metabolism. Under anaerobi c conditions, it seems to persist longer (t 1/2 = 86 days). In the last risk as sessment performed on these chemicals, there were exceedances

of acute and chronic levels of concern for both freshwater and estuarine/marine aquatic animals, as well as benthic organisms. The acute and chronic levels of concern (LOCs)

were not exceeded for listed or non-listed ma mmals or birds. For environmental fate and ecological risk assessment supporting the forthcoming registration review, all the available environmental fate and ecologi cal effects data will be evaluated.

MGK Comment: Page 6. Ecological Toxicity Data Gaps, the Pyrethrins Joint Venture and Piperonyl Butoxide Task Force II, of which MGK is a member, has provided EPA with a special study design under the GLN 850.1020, to investigate th e acute aquatic toxicity of combinations of concentrations of pyrethrins and piper onyl butoxide (PBO). Studies are underway determining the LD 50 of Hyalella Azteca to these different combinati ons of concentrations. We

will be able to determine both the critical concentr ations of PBO and pyrethrins as well as what ratio of PBO to pyrethrins result in the greatest LD 50 . This will be extremely useful information from which data with other pyrethroids can inform any synergistic effect of PBO and pyrethroids

in the environment.

EFED Response: EFED acknowledges the comment a nd supports the data submission.

MGK Comment: Page 11. With respect to Water Qualit y, pyrethrins have a very short half life in the environment, degrading rapidly in sunlight. Therefore we are very surprised to read of 11 body-of-water impairments listing pyrethins. We will respond further during Registration

Review.

EFED Response: It was noted that the summary doc ument says that there are several bodies of water impaired due to the presence of pyrethroids (not pyr ethrins). However, pyrethroids are related synthetic chemicals w ith a similar backbone structure. EFED will be investigating whether pyrethrins were dire ctly or indirectly implicated in these impairments.

MGK Comment: Page 11. With respect to CDPRs recent proposed restrictions to 17 pyrethroids used by pest control a pplicators, we would like to point out to EPA that pyrethrins is

NOT one of the 17.3 EFED Response: Acknowledged. The proposed DPR Regulation No. 11-004, which contains the full list of 17 pyrethroid active ingr edients affected by the rule, is located at http://www.cdpr.ca.gov/docs/le gbills/rulepkgs/11-004/notice.pdf

.

MGK Comment: Page 12. MGK recognizes the importa nce of more refined use and usage information to inform and refine ecological ri sk assessments for pyrethrins. MGK and the Pyrethrins Joint Venture (PJV) will do their utmo st to provide more detailed information as outlined in the Summary document.

EFED Response: Refined use and usage information will be valuable information that EFED will consider in the forthcoming eco logical risk assessment, especially if

refinements are needed.

MGK Comment: As a member of the Residential Expos ure Joint Venture (R EJV), the original survey database, and the new one just getti ng underway, will provide highly refined use and usage information for consumer products containing pyrethrins. We urge the Agency to use the Surveys since they can be mined for detailed information that can refine ecological risk assessments for outdoor products.

EFED Response: Information derived from these surveys will be considered in deriving accurate use profiles of pyrethrins in the forthcoming ecological risk assessments.

MGK Comment: Pyrethrins when synergized with PBO, are important and useful Vector control product, as a mosquito adulticide. The short half-lives of pyrethrins minimize impacts on the environment and non-target species. Adulti ciding products are in development which can be sprayed over organic crops to provide more co mprehensive vector cont rol for organic food.

EFED Response: EFED acknowledges the comment. Since adulticides are more efficacious if they come into contact with in sects in flight and le ss effective if applied directly to water, they are applied as mists th at remain in the air for longer periods than traditional agricultural sprays. It is noted th at while hydrolysis and photolysis half-lives are relatively short, adulticide applications of pyrethrins are likely mainly at dawn/dusk hours where the level of light is minimal and therefore during these times photolysis would be significantly slower. The modeling approach will be refi ned to include spray drift using the AG ricultural DISP ersal model (AGDISP v. 8.13 1 ) rather than assuming default spray drift parameters (used for agricultural applications) in PRZM/ EXAMS.

AGDISP will be used to estimat e the application efficiency and downwind deposition to the water body as a result of a dulticide application. Results of the Spray Drift Task Force (SDTF) field studies were used to va lidate the model resu lts under agricultural conditions. Despite the differences between agricultural and mosquito adulticide

1 See the following site (accessed 03/12/2012) http://www.epa.gov/pesticides/science/efed/policy_guidan ce/team_authors/endangered_s pecies_reregistration_work group/esa_agdisp_fardrift.htm4 applications, reports from researchers also suggest that AGDISP is an appropriate prediction tool for mosquito adulticide applications ( e.g. , Mickle 2005 2 ). The output parameters of major interest to EFED from AGDISP are the a pplication efficiency or the spray block deposition (fracti on of the material that de posits in the swath under the aircraft) and the downwind depos ition (equivalent to the spra y drift, obtained from the toolbox “Deposition Assessment”). The applicati on efficiency and the level of drift from Ultra Low Volume (ULV) applications derive d from this model will be used in the aquatic exposure models PRZM/EXAMS. As noted in the Re-registration Eligibility Decision EFED chapter, both the levels of drift and application efficiency are substantially decreased when the boom height was higher than initially assumed.

MGK Comment: Page 16. Ecological effects: Yes, by direct contact pyrethrins is highly acutely toxic to bees, but we would like to po int out because of the short half-life in the environment pyrethrins would not ha ve long-term toxicity to bees exposed to treated foliage over

time.

EFED Response: EFED Response: Per the previous comment, EFED will characterize the environmental fate of pyrethrins using a ppropriate models and field residue data. Regarding the potential for pyrethrins to cause adverse effects on bees as a result of exposure due to existing uses of the chemicals, EFED will utilize avai lable information to qualitatively characterize potential risks to bees and the need for appropriate label language. EFED further notes that proce dures for quantifying risks to honeybees and other insect pollinators and the data needed to inform that process will be evaluated at a FIFRA Scientific Advisory Panel (SAP) curren tly anticipated in fall, 2012. Based on the outcome of this SAP, the need for any additional data fo r evaluating risks to pollinators and/or appropriate label la nguage will be determined.



### Physicians Committee for Responsible Medi cine Comment on Avian Toxicity Test

PCRM Comment: The Summary Document indicates that the Agency may request testing for avian acute oral toxicity, however , available data already exists for six pyrethroids (Allethrin, Cypermethrin, Metofluthrin, Re smethrin, Tefluthrin, and Tetr amethrin), with the Agency requesting testing for an additional 10 through th e Registration Review process. While it is understood that the CMG designation applies to mammalian toxicity, the Agency should

consider whether this is also the case for avian acute toxicity. Is it simp ly unacceptable to test every single member of thes e two groups of substances in lethal bird tests.

EFED Response: As of July 1, 2008, the CFR 40 Part 158 pesticide data requirements

now include avian acute oral data for one passerine species and either a waterfowl or an upland game species for outdoor end-use pestic ides for all new federal actions (72 FR 60957, dated October 26, 2007). Additional avian acu te oral toxicity data for passerine species are intended to provide informa tion to assess differential sensitivity on a

2 Mickle, R.E. 2005. Direct comparison of deposit from aerial and ground ULV applications of malathion with AGDISP predictions. A report to Institut national de sant é publique du Québec (INSPQ) by REMpC Consulting, dated 02/10/2005 (REMSpC Report 2005-02).5 chemical-specific basis, determine whether a ssumptions of allometric relationships can be confidently applied to chemical classes th at have not been tested, and to include a taxonomic group of avian wildlife that is highl y represented in most pesticide use areas and may potentially exhibit differences in metabolic rate, physiol ogy, and toxicokinetics from the currently tested waterfowl and upland game test species.

Only a small pesticide toxicity data set is available for passerine species of birds. Currently, no acceptable avian acute oral da ta with a passerine species have been submitted to the Agency for pyrethrins or any pyrethroid, including the six pyrethroids mentioned in the public comment (allethri n, cypermethrin, metofluthrin, resmethrin, tefluthrin and tetramethrin). Furthermore, a recent study by Addy- Orduna et al. (2011) indicated that some passerine species may be up to 13X more sens itive than some nonpasserine species to form ulated beta-cyfluthrin 3 . As additional information on the toxicity

of this class of insecticides to passerine species becomes available, options for bridging toxicity data for additional passerine species could be considered.

3 Addy-Orduna, L, Zaccagnini, M, Canavelli, SB, Mineau, P. 2011. Formulated Beta-Cyfluthrin ShowsWide Divergence in Toxicity among Bird Species. J. Toxicol. vol. 2011, Article ID 803451, 10 pp.