UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460 

### FEB 06 

## 2012

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION
MEMORANDUM SUBJECT: 

### BEAD Chemical Profile for Registration Review: Dichlobenil (027401) FROM: 

### Monisha Kaul, Biologist 

# fYlOiuoW**I~** Biological Analysis Branch Rafael Prieto, Environmental Protection Specialist

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

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THRU:

TO: 

### John Faulkner, Economist 

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# v1 nl Economic Analysis Branch 

## (J'I.TI v, I

## ~ Biological and Economic Analysis Division (7503P) Arnet Jones, Chief Biological Analysis Branch Diann Sims, Chief

# ;{}L~**~** Science Information and Analysis Branch

# ~~ Timothy Kiely, Chief**~** 

### Economic Analysis Brancn0 Biological and Economic Analysi ivision (7503-P) Eric Miederhoff, Chemical Review Manager Risk Management and Implementation Branch 3 Pesticide Re-evaluation Division (7508-P) 

### Product Review Panel date: December 7, 2011 INTRODUCTION 

### The purpose ofthis document is to convey usage information and a broad overview ofthe pest management roles ofpesticides that are beginning to undergo registration review. The
1anticipated audience consists ofthe team ofEPA staffcurrently evaluating the registration status ofdichlobenil, and eventually the general public. This documentbuilds uponthe data already provided inthe "Usage and Label Use DataPackages" that are also providedto Registration Reviewteams byBEAD. The document is based on information and data available to BEAD as ofNovember 22,2011. Dichlobenil is a pre-emergentherbicide registered to control grasses and broadleafweeds on a variety ofuse sites. Dichlobenil acts by inhibiting cell wall synthesis. Itis classified by Herbicide Resistance Action Committee as Group L and bythe Weed Science Society of America (WSSA) as Group 20 ora nitrile (WSSA, 2011). 

### USE SITES Agricultural Use Sites The registered agricultural use sites for dichlobenil include apples, grapes, cherries, caneberries, blueberries, pears, plant nurseries, shelterbelts, nut trees, and various other crops such as filberts, huckleberries, laurel, rhubarb, and strawberries. Non-Agricultural Use Sites The registered non-agricultural use sites for dichlobenil: In and around ornamental plantings, drain lines, drains, irrigation supply systems, sewage system, waste water systems, sewer lines, cesspools, storm sewers; non-crop areas, military installations, buildings, roadways, rights-ofway, roadsides, roadways, parkways, rail yards, industrial sites, asphaltpaving, parking lots, walks, driveways, parking areas, pre-paving treatment, sidewalks, paved areas, fencerows, and vinyl swimming pool liners. 

### COMMON FORMULATIONS AND APPLICATION METHODS Dichlobenil is formulated as microencapsulated, wettable powder, granular, water soluble packages, and soluble concentrate. 

### USAGE Agricultural Usage Based on limited private marketpesticide usage data, dichlobenil annual agricultural usage averaged 5,000 pounds ofactive ingredient (A.I.) treating an average of2,000 acres for the years 2001-2010 for an overall average of2.5 pounds per acre. Because limited data are available for dichlobenil, BEAD is unable to provide accurate details as to this chemical's major crops, main states where this chemical is used, or generate a trend by crop analysis. However, using the available data, we were able to generate a graph (Figure 1), depicting total pounds AI ofdichlobenil (Proprietary data, 2001-2010). This figure illustrates a wide variance inthis chemical's reported usage.

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### Fi e 1. 

### Total A ·cultural Usa e ofDichlobenil for Years 2001-2010. 12,000 .....--------------------------



## .... 8 N N 

### 8 N m o o N


### Source: Proprietary data, 2001-2010. 

### Non-agricultural usage ¢ 

### 8 N .n o o N Year \Q o o N 

## " 8 N 00 o o N en o o N o


### .... o N



### Based on the data available to BEAD, it appears that dichlobenil has more non-agricultural usage than agricultural usage. According to KLINE and Company data, this chemical's usage in golf courses hasjumped from 58 pounds AI in 1999 to 426 in 2006. Onturf

### and landscape, this chemical's usage fluctuated. For lawn care operators, usage has significantly declined from 1999 to 2006. OnNursery/greenhouse, usage has generally been increasing from 1999 to 2006. 

### Kline Segment 

### 1999 2002 2004 2006 (LbsAl) (LbsAl) (LbsAl) (Lbs AI) GolfCourses 58


### - - 426 Institutional Turf 17,880 4,408 3,415 9,881 Landscape 1,598 13,824 494 2,551 Lawn Care Operators 16,056 1,422 

## - 612 Nurse, ry/Greenhouse 2,452 3,206 2,492 4,024 

### Data are not avrulable Source: KLINE and Company Inc., 1999,2002,2004, and 2006.
Additional data were obtained from California Department ofPesticide Regulation (DPR) because ofthe limited data ondichlobenil available to BEAD. Rights ofway and sewage systems are the top two uses inCalifornia, with an average ofapproximately 9,500 pounds AI for rights ofway, and 8,400 pounds AI for sewage systems. (California DPR, 2008-2010)



### 3BIOLOGICAL ASPECTS RELEVANT TO DICHLOBENIL There are no reports ofweed resistance to dichlobenil inthe U.S. (HRAC, 2011). There have been shifts inuse ofdichlobenil as shown in Figure 1. Research has indicated that some growers may be concerned about crop damage as a result ofrepeated use ofdichlobenil (Sandler, et al., 2004). Approved section 18 emergency exemptionuse ofmesotrione to replace dichlobenil also indicates shifts in grower needs around 2004 through 2006. However, according to Sandler et al. (2004), research studies onthe phytotoxicity ofdichobenil have had mixed results. Pre-emergentherbicides other than dichlobnil are used onmore crop area for weeds commonlytargetedby dichobenil such as dandelion, orchardgrass, and quackgrass (proprietary data,2001-2010). Furtherresearch is required to determine the needs ofdichlobenil for specific crops and pests. mSTORY OF BEAD ASSESSMENTS FORDICHLOBENIL Mesotrione was requested as an emergency exemption (2004-06) for use on cranberries because the registered alternative, dichlobenil, causes crop phytotoxicity and permanent loss oflong-term productivity with continued use at the maximum rates. INFORMATION THAT MAY BE USEFUL FORBEAD'S FUTURE WORK ON DICHLOBENIL Obtaining additional information onthe following items would improve future BEAD assessments ofthe importance ofdichlobenil and may berequired as part ofthe registration review ofthis pesticide: pounds AI, areatreated, typical applicationrates by crop/site for both agricultural and non-agricultural uses. REFERENCES California DPR, 2008-2010. Online: http://www.cdpr.ca.gov/docs/pur/purmain.htm. KLINE and Company Inc., 1999,2002,2004, and 2006. Proprietary data, 2001-2010. RED (Reregistration Eligibility Document): http://www.epa.gov/oppsrrd1IREDs/0263red.pdf

. Sandler, H.A., 

### J. Manson, W. R. Autio, T. A. Bewick, 2004. Effects ofrepeat annual applications ofdichlobenil onweedpopulations andyield components ofcranberry. Weed Technology, 18(3):648-657. WSSA, 2011. Cellulose inhibitors (L/27) resistant weeds. Online: http://www.weedscience.org/Summary/UspeciesMOA.asp?lstMOAID= 19
. Verified: October 11,2011.

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