**ME MORA** **NDU M**  **DA TE**  **D 10**  **- 4**  **- 2012**  From : Steve Funk, HED/RAB3 To: Barbara Madden, MUT/RD Subject: Justification of the Cucurbit Group Tolerance (Inclusive of Cucumber Greenhouse Use)

Flonicamid Barbara and Sidney, The rationale for increasing the cucurbit group tolerance to encompass cucumber from greenhouses as opposed to creating a separate tolerance for cucumber is summarized on page 24 of Appendix II of the Summary

Document of 10/02/2012 (D396902.me1).

**"**

### The existing tolerance f **or cucurbit vegetables is 0.4 ppm. This is based on the evaluation of crop field trial data for summer squash, cantaloupe, and cucumber (D290386, A.**  **Acierto, 04/22/2005). The highest residues were 0.17 ppm on squash, 0.34 ppm on cucumber, and 0.25 ppm**  **on cantaloupe. The recommended tolerance of 1.5 ppm for cucurbit vegetables is appropriate for the representative commodities.**  **"** Here is a detailed explanation: At the time that the original group tolerance of 0.4 ppm was established, no statistical procedure for estimation was used. It was common practice to estimate the tolerance slightly above the highest field trial result. Thus, estimates would have been 0.2 ppm (based on squash), 0.4 ppm (based on cucumber), and 0.3 ppm (based on cantaloupe). The highest value (0.4 ppm) is adopted. The guidance is that the lowest estimate and the highest estimate should not differ by more than a factor of 5X, , 0.4 / 0.2 = 2 X in this case. The estimate for cucumber from the greenhouse cucumber trials is 1. 5 ppm. 1.5 / 0.2 = 7.5, which is in excess of the 5X allowed. The apparent conclusion would be that a group tolerance is not appropriate. However, the new cucumber value is based on the use of the Organization of Economic Cooperation and Development (O ECD) calculation procedure. In order to make an appropriate comparison, the field trial data reviewed in 2005 (D290386, 04/22/2005; MRID 45854808) were re -evaluated with the OECD calculator. The findings are as follows: 

### Flonicamid Cucurbit Field Tria ls Tolerance Estimates Based on OECD Procedure (2005 Data) **Flonicamid Cucumber**  **MRID 45854808 0.3 lb ai/A, 0 d PHI**  **Total number of data (n)** 6 **Percentage of censored data** 0% **Number of non -**  **censored data** 6 **Lowest residue** 0.138 **Highest residue** 0.324 **Median residue** 0.220 **Mean** 0.216**Standard deviation (SD)** 0.067

**Correction factor for censoring (CF)** 1.000 **Proposed MRL estimate**

**- Highest residue**  0.324

**- Mean + 4 SD**  0.484

**- CF x 3 Mean**  0.649 **Unrounded MRL** 0.649 **Rounded MRL 0.7**  High uncertainty of MRL estimate. [Small dataset]

**Residues (mg/kg) n**  0.138 1 0.153 1 0.216 1 0.224 1 0.242 1 0.324 1
**Flonicamid Cantaloupe**  **MRID 45854808 0.3 lb ai/A, 0 d PHI**  **Total number of data (n)** 6 **Percentage of censored data**  0% **Number of non -**  **censored data** 6 **Lowest residue** 0.138 **Highest residue** 0.324 **Median residue** 0.227 **Mean** 0.219 **Standard deviation (SD)** 0.068 **Correction factor for censoring (CF)** 1.000 **Proposed MRL estimate -**  **Highest residue** 0.324

**- Mean + 4 SD**  0.489

**- CF x 3 Mean**  0.656 **Unrounded MRL** 0.656 **Rounded MRL 0.7**  High uncertainty of MRL estimate. [Small dataset] **Residues (mg/kg) n**  0.138 1 0.153 1 0.216 1 0.238 1 0.242 1 0.324 1

**Flonicamid Summer Squash**  **MRID 4584808 0.3 lb ai/A, 0 d PHI**  **Total number of data (n)** 5 **Percentage of censored data** 20% **Number of non -**  **censored data** 4 **Lowest residue** 0.040 **Highest residue** 0.164 **Median residue** 0.142 **Mean** 0.123 **Standard deviation (SD)** 0.048 **Correction factor for censoring (CF)**  0.867 **Proposed MRL estimate -**  **Highest residue** 0.164

**- Mean + 4 SD**  0.317

**- CF x 3 Mean**  0.321 **Unrounded MRL** 0.321 **Rounded MRL 0.4**  High uncertainty of MRL estimate. [Small dataset] **Residues (mg/kg) n**  < 0.04 1 0.128 1 0.142 1 0.143 1 0.164 1 The tolerance estimate values are 0.7 (based on cucumber), 0.7 (based on cantaloupe), and 0.4 ppm (based on summer squash). The estimate for greenhouse cucumber is 1.5 ppm. The difference between the highest and lowest estimates (1.5 /0.4 = 3.8X) is <5X. Therefore, a cucurbit group tolerance of 1.5 ppm is possible. Steve Funk OPP/HED/RAB3, S - 10318 tele: 1 - 703- 305- 5430 cell: 1 -240 - 374 -8439 fax: 1 - 703- 305- 0871