UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D C, 20460

DEC 0 2 20 10

OFFICE OF CHEMICAL SAFETY

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MEMORANDUM

SUBJECT: BEAD Chemical Profile for Registration Review on Asulam, Sodium Salt

(106902)

FROM: Sunil Ratnayake

Biologist, Biological Analysis Branch

Sepchr Haddad, Environmental Protection Specialist

Science Information and Analysis Branch

THRU:

G} 0) Derek Berwald (,' ( l\.\

Economist, Economic Analysis Branch n. J "-

Biological and Economic Analysis Division (7503P)

Arnet Jones, Chief A

Biological Analysis Branch

Diann Sims, Chief

Science Information and Analysis Branch

Timothy Kiely, Chief !\"'\\,'v\! ' 0

Economic Analysis Branch \j j

Biological and Economic Analysis Division (7503P)

TO: Rusty Wasem, Chemical Review Manager

Pesticide Re-evaluation Division (7508P)

Peer Review Panel Date: August 31, 2010

INTRODUCTION

The purpose ofthis document is to convey usage information and a broad overview ofthe pest

management roles of pesticides that are beginning to undergo registration review. The

anticipated audience consists ofthe team ofEPA staff currently evaluating the registration status

of Asulam, and eventually the general public. This document builds upon the data already

provided in the "Usage and Labe l Use Data Packages" that are also provided to Registration

Review teams by BEAD.

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Asulam, sodium salt is a herbicide which belongs to the carbamate chemic al group and it is used

to control a variety of annual grasses and broadleaf weeds in sugarcane, Christmas tree

plantations, ornamental and shade trees, ornamental woody shrubs and vines, turf(St.

Augustinegrass and Bermudagrass) and non-cropland uses (boundary fences, fencerows,

hedgerows, lumberyards, storage areas, industrial plant sites, and warehouse lots) (EPA

proprietary data, 2010). It is a systemic herbicide and applied as a post-emergence herbicide.

Currently, five product registrations are active under this active ingredient (EPA proprietary data,

2010). Asulam, sodium salt is absorbed by leaves, shoots and roots. The mode of action of

asulam sodium salt is inhibition of 7,8-dihydropteroate (DHP) synthase, an enzyme invo lved in

folic acid synthesis (PPDB, 20 I0). Aerial and ground applications are recommended as

application methods ofthis herbicide (Asulam Product Label, 2002).

COMMON FORMULATIONS AND APPLICATION METHODS

Asulam, sodium salt is form ulated as a liquid only. Asulam sodium salt is applied as a band

treatment, aerial, or as ground application using tractor mounted sprayers.

USAGE

Agricultural Usage

Based on private market pesticide usage data, the annual total agricultural usage averaged

approximately 900,000 pounds active ingredient (A.I.) for 350,000 acre s from 1998-2008 (GfK

Kynetec, 1998-2008) (Fig. 1). The peak of use in pounds A.I. and acres treated occurred in

1999 with a steady decrease in use and acres treated through 2008 . Use decrease d by over 60%

between 2007 and 2008.

Figure 1. Acres Treated with Asulam Sodium from 1998 to 2008.

Asulam Acres Treated

600000

0 '-

1998 1999 2000 2001

Source: GfK Kynetec, 1998-2008

2002 2003 2004 2005 2006 2007 2008

Year

2
Figure 2. Usage of Asulam, Sodium Salt in Sugarcane

Sugarcane

1.600.000

a.

a.

:;;:'"

."

•

C,

o

..

o

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Year

Source: GIK Kynetec, 1998-2008

From 1998-2008, the largest market in terms oftotal pounds of active ingredie nt applied and

acres treated was for sugarcane, with a very minimal amount (less than 1%) used on sugar beets.

(GIK Kynetec, 1998-2008) (Fig. 2).

Fi ure 3. A ricu.tura) Usa e of Asulam, Sodium Salt in Different States

Pounds A."

Source: GIK Kynetec, 1998-2008

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The states with the most agricultural usage in terms of pounds A I. applied are Florida and

Louisiana with 83% and 17 %, respectively. (GfK Kynetec, 1998-2008) (Fig. 3). There was also

some use in Texas and Montana; however, mo re than 99 percent ofthe usage is in Florida and

Louisiana . These states are also the largest in terms oftotal acres treated from 1998-2008.

Non-Agricultural Usage

In terms of non-agricultural usage, BEAD reviewed available non-agricultural sources, but

information was limited on use of asulam in non-agricultural use sites to only turf farms

(125, 000 Ibs. A.I. in 2004, and 87,000 Ibs A.I. in 2006). (Kline & Company, Inc. 2004-2006)

BIOLOGICAL ASPECTS RELEVANT TO ASULAM SODIUM SALT

Asulam, sodium salt belongs to DHP synthase inhibitors. It inhibits the enzyme dihydropteroate

synthase. Development of weed resistance to asulam sodium salt is not reported in the

International Survey of Herbicide Resistant Weeds (International Survey of Herbicide Resistant

Weeds, 2010).

HISTORY OF BEAD ASSESSMENTS FOR ASULAM SODIUM SALT

There is no record of prior BEAD assessments for Asulam sodium salt.

DATA NEEDS RELEVANT TO BEAD'S FUTURE WORK ON ASULAM SODIUM

SALT

Usage data is needed, if ava ilable, for non-agricultural uses of industrial areas, commercial

storages/warehouse premises, and right-of-ways.

REFERENCES

Asulam. Registration Eligibility Decision Facts. E PA. 1995.

http ://,",,'W\\'.epa.govloppsrrd lIREDs/factsheetslO265fact. pdf

Asulam Product Label 4F. 2002. Helena Chemical Company.

http :/ ww cdm .n t!Label sM sd /LMDefault .aspx ?pd ~8576&t

GfK Kynetec, 1998-2008. Proprietary Data.

Pesticide Properties Database (PPDB). 20 10. Asulam, Sodium. 2010.

http ://sitem.herts.ac.uk/aeruliupac/Reports/42.htm

Kline & Company. Professional Turf and Ornamental Markets For Pesticides and Fertilizers

USA Turf Farms (2004-2007).

International Survey of Herbicide Resistant Weeds, 20 10.

http ://w."...\\..wecdrescarch.comlsummary/ChcmF amil ySum.asp?lstActivc=165&lstHRAC=14&bt

nSub ~Go

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