Thiabendazole Summary of Analytical Chemistry and Residue Data DP#: 363974

**UNITED STA TES ENVIRONMENTA**  **L PROTECTION A GENCY** 

**WA SHINGTON, D.C. 20460**  **OFFICE OF PREVENTION, PESTICIDE AND TOXIC SUBSTANCES** 
**MEMORANDUM Date**  **:** July

30 , 2014

- Draft Internal Deliberative **SUBJECT:** Thiabendazole

. PP# 3F8166

. New Seed Treatment Uses on Assorted V egetables

and S mall Grain s (vegetable, root (except sugar beet); subgroup1B, onion, bulb, subgroup 3

- 07A; Bras sica, head and stem, subgroup 5 A; vegetable, cucurbit group 9; alfalfa; spinach (including bab y) ; and small grain s (wheat, barley , oats, rye, and triticale). Amendment to Increase Rate on Soy bean. Addendum

. **PC Code:** 060101 **DP Barcode:** D 410807 addendum **Decision No.:** 47671 1, 476712 **Re gistration**  **No. :**  100

- 889, 100

- 963 **Petition No .**  **:** 3F8166 **Regulatory Action:** Section 3 Registration **Risk A**  **ss essment Type**  **:** Res Chem **Case No.:**  2760 **T XR No.**  **:** NA **CAS No.:** 148

- 79

- 8 **MRID No .**  **:** See MRID Summary Table **40 CFR:** 180. 242 Ver.Apr.08 **FROM:** Susan V. Hummel, Senior Chemist

Risk Assessment Branch 4 Health Effects Division (7509P) **THROUGH:** Thurston G. Morton, Senior Chemist

Risk Assessment Branch 4 Health Effects Division (7509P) **TO:** Rosemary Kearns/Tony Kish , PM 22 Registration Division (7505P) This memo serves to update the tolerance expression for thiabendazole and the tolerance recommendations. **860.1550 Proposed Tolerances** The current tolerance expression for thiabendazole is:

“ (1) Tolerances are esta

blished for the combined residues of the fungicide thiabendazole (2

- (4

- thiazolyl)benzimidazole) and its metabolite benzimidazole (free and conjugated) in or on the following food commodities: ” for plant commodities.Thiabendazole Summary of Analytical Chemistry and Residue Data DP#: 363974

And

“ (2) Tolerances are established for the combined residues of thiabendazole (2

- (4

- thiazolyl)benzimidazole) and its metabolites 5

- hydrox ythiabendazole (free and conjugated) and benzimidazole in or on the following food commodities: ” for livestock commodities. The tolerance expression s need to be updated as follows to reflect our current guidance. (1) Tolerances are established for residues of thiabendazole, including its metabolites and degradates, in or on the commodities in the table below. Compliance with the tolerance levels sp ecified below is to be determined b y measuring only the sum of thiabendazole (2

- (4

- thiazolyl)benzimidazole) and its metabolite benzimidazole (free and conjugated), calculated as the stoichiometric equivalent of thiabendazole, in or on the commodity

. (2) T olerances are established for residues of thiabendazole, including its metabolites and degradates, in or on the commodities in the table below. Compliance with the tolerance levels specified below is to be determined b y measuring only the sum of thiabendazole (2

- (4

- thiazolyl)benzimidazole) and its metabolites 5

- hydrox ythiabendazole (free and conjugated) and benzimidazole (free and conjugated), calculated as the stoichiometric equivalent of thiabendazole, in or on the commodity

. International Harmonization . There is no issue with International Harmonization for the current petition

. CODEX has not established any established maximum residue limits (MRL s) for thiabendazole on the requested commodities . Canada has not established maximum residue limits (MRLs ) for thiabendazole on the requested commodities. We note that the U.S. tolerance expression is not harmonized with Canada, or CODEX . This will be examined further during registration review.

**Table 8**  **. Tolerance Summary for**  **Thiabendazole . §**  **180. 242**  Commodity Current/Proposed

Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition alfalfa, forage 0.02 0.02 Alfalfa, forage alfalfa, hay 0.02 0.02 Alfalfa, hay alfalfa, seed 0.02

- Tolerances are not normally set for alfalfa seed barley , grain 0.05 0.05 Barley, grain barley , hay 0.15 0. 3 Barley, hay Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws.Thiabendazole Summary of Analytical Chemistry and Residue Data DP#: 363974

**Table 8**  **. Tolerance Summary for**  **Thiabendazole . §**  **180. 242**  Commodity Current/Proposed

Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition barley , straw 0.15 0. 3 Barley, straw Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws. Brassica, Head and Stem, subgroup 5

- A 0.02 0.02 oats, forage 0.2 0. 3 Oats, forage Revised level based on OECD tolerance calculation procedures, and to be consistent across all cereal grain forages. oats, grain 0.05 0.05 Oats, grain oats, hay 0.09 0. 3 Oats, hay Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws. oats, straw 0.09 0. 3 Oats, straw Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws. Onion, bulb, Subgroup 3

- 07A 0.02 0.02 radish, tops 0.02 0.02 Radish, tops rye, forage 0.2 0. 3 Rye, forage rye, grain 0.05 0.05 Rye, grain rye, straw 0.15 0. 3 Rye, straw Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws. spinach 0.02 0.02 SpinachThiabendazole Summary of Analytical Chemistry and Residue Data DP#: 363974

**Table 8**  **. Tolerance Summary for**  **Thiabendazole . §**  **180. 242**  Commodity Current/Proposed

Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition triticale, forage 0.2 0. 3 Triticale, forage Revised level based on OECD tolerance calculation procedures, and to be consistent across all cereal grain forages. triticale, grain 0.05 0.05 Triticale, grain triticale, hay 0.09 0. 3 Triticale, hay Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws. triticale, straw 0.09 0. 3 Triticale, straw Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws. Vegetable, Cucurbit group 9 0.02 0.02 Vegetable, Cucurbit, group 9 Vegetable, root (except sugar beet), subgroup 1B 0.02 0.02 Revised level based on OECD tolerance calculation procedures. Wheat, grain 1.0 0.05 Current tolerance for wheat grain is 1.0 ppm, tolerance recommended in RED was 0.2 ppm. Current recommendation is based on full new data set showing all non

- quantifiable residues. wheat, forage 0.2 0. 3 Wheat, forage Revised level based on OECD tolerance calculation procedures, and to be consistent across all cereal grain forages. wheat, hay 0.09 0. 3 Wheat, hay Revised level based on OECD tolerance calculation procedures, and to be consistent across all hays and straws.Thiabendazole Summary of Analytical Chemistry and Residue Data DP#: 363974

**Table 8**  **. Tolerance Summary for**  **Thiabendazole . §**  **180. 242**  Commodity Current/Proposed

Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition Wheat, straw 1.0 0.3 RED recommended lowering tolerance. Current recommendation is to be consistent across all hay s and straws.