UNITED STATES ENVIRONMENTAL PROTECT I ON AGENCY WASHINGTON , D

. C

. 20460 

## UAY 1 3 2014

OFFICE OF CHE M ICAL SAFETY A N D POLLUTIO N PRE V ENT IO N MEMORAND U M
SUBJEC T : FROM :

THRU : An Overview of the Benefits of Sulfur Use on Agricultural Crops (DP 417520) Tara Chandgoya l , Ph. D., Pl ant Pathologist Biological Analysis Branch Rafae l A
. Prieto , Environmen tal Protection Specialist 

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# fl**~** Science Information and Analysis Branch 

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# vl (N' -\. Monisha Kaul, Lead Environ mental Protection Specialist

# (J**~t) ~**  Andrew Lee , Ph
. D. , Economist 

# a (. Economic Analysis Branch
. Biological and E conomic Analysis Divi s ion (7503P) Amet Jones, Chief /)

- 

### _fiA Bio logica l Analysis

## Brand**,** 

# J
Diann Sims , Chief 

# M. Science Information and Analysis Branch Timothy Kiely, Chief 

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## ~ Economic Analysis Branch \1\A._ B i olo g ical and Economic An al is Division 3P) TO: Jose Gayoso, Chemical Review Manager Risk Management and Implementation Branch 2 Pesticide Re

- ev aluation Division (7508P) Product Review Panel: April30, 2014 SUMMARY This document quali t atively characteriz es the benefit s of sulfur used on agricultural crops. Sulfur i s registered for dozens of major and minor us e s (field crop s, vegetable crops , fru its/nuts and berries , and ornamentals) as a fungicid e/ miticide for the control of fungal d i sease s and mites. Historically , sulfur has been heav ily used in the United States on grapes, t omatoes , peaches ,oranges , app les, cherrie s , and carrots for control of fungal powdery mildew disease and mites. Sulfur i s a valuabl e p esticide in managing plant diseases because of its low cost and good efficacy. It plays an important role in pest resistance management because no fungal pest has been rep orted to have resistance to sulfur. It plays an important role in integrated pest management in organic crop production. Sulfur has been used for decades on many crops giving growers exten sive exper ience and knowledge of its use as a pesticide. 

### BACKGROUND As part of the registration review process , the Environmenta l Fate and Effects Division (EFED) conducted a risk assessment that found some crops (some varieties of gooseberr ies, currants, apricots , raspberries, and cucurbits) may be adversely affected by sulfur applications. In addition , th e risk assessment document al so mentioned that there are five known incidents of unsub s tantiated toxicity of su lfur to some crops (such as cucurbits and berries). This document provides an overview of t he benefits of sulfur use on agricultural crops and its role in pest management. 

### ANALYSIS In evaluating the benefits of a pesticide to the user, BEAD considers a number of factors. The most direct benefit of a pes ticide is its ability to control pests that would otherwise damage a crop , reducing the y ie ld and/ or the qual ity of the produce. A pesticide might also provide value to a grower if it pro v ides similar pest control at lower cost than other control measures. B EAD also considers less tangible benefits, including the role a pesticide may play in resistance management or in integrated pest management (IPM) programs. Sulfur is a natural e lement used for centuries to control plant diseases and mites (Browde and Ohmart , 2001). The top 10 (in terms of average lb s a.i. applied per year) sulfur use crops are li sted in Table 1 (EPA BEAD, 2014). Su lfur is effective in controlling powdery mildew disease and mites on various crops. Powdery mildew and mite s can cause heavy crop losses under pest favorable weather conditions and are the primary target pests for sulf ur app l ications. Table 1 also s how s that su lfur i s an inexpensive fungicide compared to most of its alternatives. Although comparative efficacy of alternatives was not considered in this analysis , the percent of crop treated with su lfur indicate s grower relianc e on it for pest management (Tab le 1 ).

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### Table 1 : High Sulfur Use Crops with Disease/Pest Controlled (2004-2012) and Average Cost of Alternatives
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- Averag e Average Sulfur Alte rnatives Crop Major Poun d s a.i. Percent Averag e Average Cost Diseases/Pests 1 Crop Cost($) I Applied 2 Treated2 Acre 3 ($) I Acre3.4 Powdery Mildew, Grapes Bu d Mite, Blister 38,900,000 80 3 22 M i te Tomatoes Powdery Mi ldew, 8 , 900,000 60 10 15 Mites Powdery M il dew, Peaches Brown Rot, Leaf 2,400,000 60 5 20 Spot, Silver M i te Oranges Mi te s 1,400,000 10 II 28 Apples Powdery Mildew, 1,300 ,000 30 7 21 Scab, Blister Mite, Powdery Mildew, C herri es Brown Rot, Leaf 1 , 000 ,000 45 6 23 Spot, Mite Ca rrots Powdery mildew, 1 ,000,000 45 7 13 M ites Grapefruit Mites 800,000 45 1 1 23 Pistachios Citr u s Flat Mite 700,000 30 1 1 25 Strawberry Powdery Mildew , 600,000 50 3 44 Red Spider Mite 1 Pest hsted as controlled by sulfur on product label s 2 Data sources include: · USDA-NASS (United States Department of Agriculture's National Agricu ltu ral Statist ics Serv ice) , 2004-2012 EPA Proprietary Data, 2004

-20 1 2 California DPR ( D epartment of Pesticide Regulation) , 2004-20 1 2 3 EPA Proprietary Data, 2008-20 12. 4 Costs of a lte rna t ives are for target pest listed in thi s table
. The costs of alternatives are a simple average across the nine years for the listed target pest s . The Fun gic ide Resistance Action Committee (FRAC, 2012) has designated sulfur as FRAC Code M2 and i s the only chemical in the group. Sulfur h as multi-site contact activity

- belong ing to the target site and code "multi-site contact activity, " and group name and chemical group "inorganic"
. 

### It i s considered as a lo w risk group for re s i stance development, w ithout any s i gns of resistance developing to this fungicide. The use of inorganic fungicides (such as sulfur, copper) has been well documented in the li terature (E li s and Bradley, 1992). Beckma n (2008) s tated , "Sulfur i s the o ldest recorded fungicide and has been used for more than 2,000 years, early in agriculture hi sto ry , the Greeks recognized its efficacy against rust on wheat. Sulfur can be used as a preventative fungicide against powdery mildew , rusts and other dis eases . Sulfur prevents fungal spores from germina tin g, so it should be applied before the disease development". Sulfur labe l states that it can be p hytotox ic to cucurbits and some varieties of berr ie s when temperature s a re 

### high
. Beckman (2008) an d others recommend ag ainst usi n g su lfur when temperatures are expected to 

### 3exceed 80°F to reduce the risk of plant phytotoxicity. This may be the reason for five known incidents of unsubstantiated toxicity of sulfur to crops as mentioned above. It is also documented that certain varieties of gooseberries, currants, apricots, raspberries, and cucurbits are susceptible to sulfur phytotoxicity. Sulfur has no known resistance by any pes t. It plays an important role in integrated pest managment and resistance management. Sulfur is used by organic crop growers because it is effective in controlling fungal diseases and mite pests on various crops. Organic crop growers use sulfur in managing crop pests on different crops. Organic crop growers use vari ous cu ltural practices to reduce pest pressure and they have a limited number of compounds (such as copper based fungicides, potassium bicarbonate, and biological fung i c i des such as Ampelomyces quisqualis) for controlling pests (Anomynous, 2014). Therefore, sulfur plays an important role in the integrated management of pests in organic production of different crops. CONCLUSION Sulfur i s an inorgani · c pesticide that plays an important role in plant disease/ pest management on many major and minor use crops because it provides effecti ve control of both fungal diseases and mites at low cost. It al so plays an important role in pest resistance management because no pest has been reported to be resistant to sulfur and can be rotated with other compounds that are prone to resistance. Sulfur is important for the organic growers because of a limited number of compounds available (such as copper and bi ologicals) for controlling pests on these crops . REFERENCES Anomynous, 2014. Accessed May 1, 2014. http: //www . oardc
. ohiostate
. edu/ fruitpathology/ organic/.fungicidesystems.htm Beckerman, J. 2008
. Using Organic Fungic i des. Disease Management Strategies. Purdue Ex tension BP-69

- W. Browde, J and Ohmart, C. 2001. Improving sulfur management. Accessed on February 3, 2014
. http: //www . practicalwinery
. com/ mayjunO 1 p ll.htm Ellis, B. W and Bradley, F .M. 1992. The organic Gardner's Handbook ofNaturallnset and Disease Control, Rodale Press. Emmaus, PA. 534pp
. EPA BEAD, 2014
. Screening Level Usage Analysis (SLUA). Biological and Economic Analysis Division , Unpublished EPA report. FRAC. 2012. Accessed on February 4 , 201 4
. http ://www.frac.info/ frac/ publicationlanhang/ FRAC code List 201 O.pdf

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