UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

 WASHINGTON, D.C. 20460

OFFICE OF CHEMICAL SAFETY AND 

 POLLUTION PREVENTION 

 

 Chemical: Propiconazole 

 PC Code: 122101 

 DP barcode: 372880 

July 6, 2010 

 

 

MEMORANDUM

Subject: Drinking Water Assessment for Propiconazole Uses on Mint (IR-4 Action), 

Caneberry Subgroup 13-07A, Bushberry Subgroup 13-07B, Low Growing Berry 

Subgroup 13-07G, except Cranberry and Bulb Vegetable Crop, Group 3-07 

To: Andrew Ertman 

 Barbara Madden 

Fungicide Branch 

Registration division (7505P) 

From: James Lin, Environmental Engineer 

 Brian Anderson, Acting Branch Chief 

 Environmental Risk Branch I 

Environmental Fate and Effects Division (7507P) 

1. Summary 

The estimated surface water drinking water concentrations for propiconazole are: 

55.78 ug /L for the 1 in 10 year annual peak concentration (acute) 

21.61 ug /L for the 1 in 10 year annual mean concentration (non-cancer chronic) and 

13.24 ug /L for the 30 year annual mean concentration (cancer chronic). 

The SCI-GROW estimated ground water drinking water concentrations for propiconazole are 

not expected to exceed 0.64 μg/L. 

These results are based on EDWCs for Turf (DP 325821, 328690, 07/07/2006). The proposed 

new uses do not result in higher EDWCs than those estimated for turf uses. 
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2. Previous Drinking Water Assessment 

EFED has issued four drinking water assessments for propiconazole: 

(1) Drinking Water Assessment of Propiconazole. (DP 312353, 06/29/2005) 

(2) Revised Drinking Water Assessment of Propiconazole. (DP 361358, 06/07/2006) The 

first two assessments addressed the following uses: wheat, seed crops (grasses), rice, 

pecans, peaches, sweet corn, dry beans, peanuts, barley, celery, turf and ornamentals – 

lawn and turf, golf course, ground cover, and sod farm. 

(3) Drinking Water Assessment of Propiconazole for Uses of Cereals, Soybean, Berries and 

Cranberries, Carrot, Onions, Sorghum, Strawberry, Sugar Beet, Mint, Tree Nuts, and 

Turf. (DP 325821, 328690, 07/07/2006) 

(4) Drinking Water Assessment for Propiconazole Uses on Garden Beet, Turnip, Leaves of 

Root and Tuber Vegetables, Herbs, and Pineapple – An IR-4 Action (DP 347906, 

07/02/2008) 

These drinking water assessments were for parent propiconazole only. The 1,2,4-triazole 

degradate is being characterized in a separate, cumulative triazole assessment and is, therefore, 

not considered in these assessments (see DP322215, 02/07/2006). The resulting drinking water 

concentration estimations (EDWCs) are based on the turf use due to its highest total application 

rate of 6.285 lb ai/ac based on 8 applications of 0.786 lb ai/ac at a 14-day interval. 

3. Proposed Label Information 

The proposed use rates are tabulated below based on the marked-up supplemental label for Tilt®. 

Crop Use Rate 

(lb ai/ac) 

Number of Applications 

/ Interval (day) 

Total Use Rate 

Per Season (lb ai/ac) 

Bulb Vegetables: 

Bulb Onions, Green 

Onions 

0.225 2 / 7 0.45 

Caneberries, 

Bushberries 

0.16875 5 / 7 0.84 

Mint 0.1125 3 / 14 0.338 

Strawberries and 

Other Low Growing 

Berries 

0.1125 4 / 7 0.45 

EDWCs were not estimated for the proposed new uses because the maximum single and annual 

application rates are approximately 3.5-fold and 7.5-fold lower, respectively, than the turf use. 

Therefore, EDWCs for the proposed new uses would not supersede EDWCs for turf. 
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4. Conclusion 

The proposed use rates are much less than the total turf use rate of 6.285 lb ai/ac, which is based 

on 8 applications at a rate of 0.786 lb ai/ac with a 14-day interval. Therefore, the turf drinking 

water assessment should be used to represent estimated drinking water concentrations.