EPA Meeting with Tetrachlorvinphos Registrants to discuss the Registration Review

Generic Data R equirement Waiver Responses

November 02, 2010

Participants

James Parker/PRD

Laura Parsons/PRD

Neil Anderson/PRD Michael Metzger/HED

Paul Chin/HED

Christine Olinger/HED Greg Orrick/EFED Bruce Bernard/Hartz and KMG Representative

John Riner/KMG Consultant Roger Jackson/KMG

- Bernuth

Robert Rosenwasser/Hartz Mountain

On November 02, 2010, the EPA met with the tetrachlorvinphos (TCVP) registrants (and consultants) also known as the Tetrachlorvinphos Task Force (TCVP TF) at their request to discuss the Agency’s responses to data waivers submitted to the Agency as a part of their 90 day response to the generic data call

- in (GDCI). During this meeting, the Agency cl arified that the TCVP samples used in earlier studies (under PC Code 083701) have been identified as equivalent to samples which have been used in more recent studies (under PC Code 083702). Therefore, the TCVP technical grade active ingredient (TGAI) us ed in all studies submitted to the Agency consisted of the Z

- isomer

, regardless of chemical name and CAS numbers used.

Also, the TCVP TF agreed to submit two inhalation protocols to the Agency for review which will be used to support the registration rev iew human health risk assessment by providing additional inhalation exposure data (per Organophosphates my cause respiratory lesions)

. During the meeting

, the TCVP TF also indicated that TCVP would not result in exposures of

more than 14

- days . As a resul t, the TCVP TF indicated that they preferred not to submit the 28 day guideline study, but instead would submit two protocols for alternate inhalations studies (along with supporting data). The two protocols which the TCVP TF indicated that they would

submit to the Agency include d a 14 day inhalation protocol (with a 14 day continu ation

, in case effects are identified) and a 28 day inhalation protocol, both of which will be based on a validated gravimetric method. Once these protocols are submitted, th e Agency will determine whether or not either of these study protocols will be acceptable by the Agency.

This meeting also covered the TCVP GDCI data requirements for a manure dissipation study and environmental chemistry methods in soil and water. In regards to the Manure dissipation study, the Agency indicated that the previous Manure dissipation study did not follow the protocol approved by the Agency and excluded the TCVP parent compound. T he TCVP TF agreed to submit a protocol (which would include data to indicate the number of animals used) for a non

radiolabeled (cold) Manure Dissipation study , which will be reviewed by the Agency

. The typical end

- use product should be used as directed for this study (manure should not be treated

with TCVP after passing from the livestock) . Residues in manure should be analyzed for TCVPand the transformation products of concern to determine the decline of parent compound and the

formation and decline of transformation products once passed from livestock. If di fferent from submitted analytical methods in soil, the analytical method used in the study will need to be validated and independently validated following OCSPP guidel ine 850.6100 (formerly 850.7100;

40 CFR Part 158.1300

, which requires independent validat ion of field studies other than combination and tank mix studies)

.

Also, g uideline

- compliant (OCSPP guideline 850.6100) independent laboratory validation (ILV)

reports are required to support the submitted analytical methods in water and in soil , in add ition

to a guideline

- compliant report for the analytical method in soil (as discussed in the Agency’s July 20, 2010 EFED Response to Comments and Waiver Requests document (DP346876)).

The registrants indicated that data were submitted indicating that dime thyl hydrogen phosphate is the main phosphate

- containing degradate. The Agency indicated that the dimethyl phosphate

containing degradate are not of concern for human health

. However, the Agency would determine whether there are ecological concerns for the dimethyl phosphate

- containing degradates

, which should be included as analytes in the manure dissipation study ( the degradates that are of concern to the Agency were forwarded to the registrants via email on November 16, 2010).

In conclusion, t his m eeting also covered data requirements for several outdoor ecological data requirements, which remain as data gaps (as discussed in the 7/20/10 response to waiver request) for which the TCVP TF indicated that they intend to submit the appropriate data to sa tisfy these ecological data requirements

.