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provided in the “Usage and Label Use Data Packages” that are also provided to Registration 

Review teams by BEAD. The document is based on information and data available to BEAD as 

of December 17, 2010. 

Isoxaflutole is a postemergence herbicide used in corn to control broadleaf and grass weed 

species. This herbicide is a cyclopropylisoxazole chemical with the mechanism of action of 

inhibiting the enzyme used in carotenoid synthesis. It is classified by the Herbicide Resistance 

Action Committee and Weed Science Society of America in group F227.

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 Currently, there are no 

confirmed weed species or biotypes reported as resistant to this herbicide in the U.S. 

USE SITES 

Isoxaflutole is registered for use on field corn. 

COMMON FORMULATIONS AND APPLICATION METHODS 

Isoxaflutole may be formulated as water dispersible granules, emulsifiable concentrate, or as a 

soluble concentrate. 

The herbicide can be applied by ground boom and can be incorporated (shallow) into soil above 

the seed planting zone (no aerial application). 

USAGE 

Based on private market survey data from 1998-2008, usage on corn averaged approximately 

250,000 pounds for nearly 4.5 million acres (GfK Kynetec, 1998-2008). Isoxaflutole is typically 

applied once per year at a rate of approximately 0.06 pounds per acre (GfK Kynetec, 1998-

2008). 

The states with the most agricultural usage in terms of pounds AI applied are: Iowa, Illinois, 

Nebraska, Indiana, South Dakota, and Ohio (Figure 1). The ranking was the same in terms of the 

total area treated. 

Figure 1. States with Highest Isoxaflutole Use- Percent of Total Lbs A.I. Applied 

Source: GfK Kynetec, 1998-2008 

 

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 http://www.hracglobal.com/Publications/ClassificationofHerbicideModeofAction/tabid/222/Default.aspx 

Iowa

36%

Illinois

18%

Nebraska

13%

Indiana

11%

South Dakota

6%

Ohio

6%

Other

10%
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USE TRENDS 

The historical usage data provided in this section is provided for preliminary scoping purposes 

only, to convey a broad overview of Isoxaflutole at the beginning of the registration review 

process. 

 Source: GfK Kynetec, 1998-2008

BIOLOGICAL ASPECTS RELEVANT TO ISOXAFLUTOLE 

Currently, there are no confirmed weed species or biotypes reported as resistant to this herbicide 

in the U.S. In addition, this herbicide is often used to control weed species and biotypes that are 

resistant to other herbicides (e.g. glyphosate). 

HISTORY OF BEAD ASSESSMENTS FOR ISOXAFLUTOLE 

There have been no Section 18 requests evaluated by BEAD for this chemical. 

BEAD Environmental Chemistry Laboratory (ECL) reviewed the method (MRID No. 471716-

01) for detection of Isoxaflutole and its primary metabolite RPA 202248 in surface water and 

ground water submitted by Bayer CropScience in accordance with the registration of 

Isoxafluotole. ECL concluded that this method was acceptable with minor deficiencies (EPA 

2008). 

DATA NEEDS RELEVANT TO BEAD’S FUTURE WORK ON ISOXAFLUTOLE 

Obtaining additional information on the following items would improve future BEAD 

assessments of the importance of Isoxaflutole and may be required as part of the registration 

review of this pesticide. 

At this time BEAD has no data needs. 

0

400,000

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Pounds A.I. Applied

Year
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REFERENCES 

GfK Kynetec. 1998-2008. EPA Proprietary Data 

EPA/OPP/BEAD. Environmental Chemistry Laboratory. Isoxaflutole in Water Method Review 

Report No. ECM0236W1-W2. DP Barcode: 342502. 2008.