CAS No. 141112-29-0

Conditions for use led Bayer CropScience to not register the product.

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From: Wisconsin Department of Agriculture, Trade and Consumer Protection

Use of Isoxaflutole Pesticides in Wisconsin

Pesticides containing the active ingredient isoxaflutole will not be sold in Wisconsin in 2003.

The need to protect Wisconsin’s water resources led the Department of Agriculture, Trade and Consumer Protection to require special restrictions and conditions if the corn herbicide, Balance Pro, was to be used in Wisconsin. Because of the added environmental requirements, Bayer CropScience, the pesticide manufacturer, has decided not to distribute the product in Wisconsin in 2003.

In 2002, the department decided that Balance Pro herbicide could be registered for use in Wisconsin for the 2003 growing season. However, Bayer CropScience, (formerly Aventis CropScience) the manufacturer of the herbicide, had to agree and comply with a number of restrictions and requirements before Balance Pro could be distributed, sold or used in Wisconsin. Following a review of Wisconsin’s order issued for the product that detailed the added restrictions and requirements, Bayer CropScience declined the opportunity to register the product in Wisconsin.

Press Release (Dec 27, 2002) - [also listed below]

Environmental Impact Evaluation

Evaluating the potential use of isoxaflutole in Wisconsin required the development of an Environmental Impact Statement (EIS) outlining the potential benefits as well as environmental, social and economic impacts of its use. Water Quality section staff prepared an EIS, held public hearings and convened an advisory group to look at this issue. Based on the comments received and input from the advisory group, DATCP determined that additional use restrictions and monitoring specific to Wisconsin are required to minimize the risks associated with the use of isoxaflutole.

Additional Use Restrictions

The additional use restrictions to be included on each label of product sold for use in Wisconsin include:

• Isoxaflutole may not be used in eight counties (Adams, Juneau, Langlade, Marathon, Portage, Waupaca, Waushara and Wood) and the lower Wisconsin River Valley which have proven susceptible to groundwater contamination.
• Isoxaflutole may not be used on coarse soils with low organic matter, less than 25 feet to groundwater.
• Isoxaflutole use under irrigation requires an irrigation management plan.
• Isoxaflutole may not be applied before April 15th or after July 31st of any crop year.
• No use of isoxaflutole will be allowed on tile-drained fields.

Environmental Monitoring/Reporting Requirements

In addition to the restrictions on the use of isoxaflutole, DATCP will require environmental monitoring and use reporting to ensure that the restrictions adequately protect other crops and the environment. The additional requirements are:

• Groundwater monitoring with DATCP suspending use based on a single confirmed groundwater detection of isoxaflutole above 310 parts per trillion.
• Four surface water monitoring systems must be established and sampled in Wisconsin.
• All uses of isoxaflutole must be reported to the department.

Isoxaflutole Use Nationwide

Isoxaflutole is currently used in 18 states. It has been used under a conditional registration from the U.S. Environmental Protection Agency since 1999. A conditional registration was issued by EPA because of data indicated that use may result in possible water contamination and effects on non-target plants, including vegetable crops. Because of these concerns, Wisconsin, Minnesota, and Michigan have not agreed to allow use of isoxaflutole up to this point.


You will need a PDF viewer for the following documents.

Final Environmental Impact Statement - 85 page PDF - August 2002
Copies of the final EIS are also available from public libraries, county extension offices, county land conservation departments, and the department.

Special Local Need Finding - 2 page PDF - November 8, 2002
The determination that a special local need exists in Wisconsin for the pesticide isoxaflutole.

Order Granting Special Local Needs Registration with Conditions - 9 page PDF - 2002
A legal document that contains the requirements and restrictions to be met in order to register isoxaflutole-containing products for use in Wisconsin.

Advisory Group - 2 page PDF
Included grower representatives, environmental groups, water quality specialists, health specialists, weed scientists, and the product manufacturer.

For more information on isoxaflutole or other groundwater issues, contact Jim Vanden Brook at 608-224-4501 or send an email .

Press Release
Wisconsin Department of Agriculture, Trade and Consumer Protection

December 27, 2002

Balance Pro Herbicide Will Not be Sold In Wisconsin in 2003

Contact: Jane Larson

MADISON--The need to protect Wisconsin's water resources led the Department of Agriculture, Trade and Consumer Protection to require special restrictions and conditions if a new corn herbicide was to be used in Wisconsin. Because of the added environmental requirements, Bayer CropScience, the manufacturer of Balance Pro herbicide, has decided not to distribute the product in Wisconsin in 2003.

In 1999, the state agriculture department first made the decision that pesticides containing the active ingredient isoxaflutole (eye-SOX-a-flew-tall) could not be used in Wisconsin. This decision was based on information from the federal Environmental Protection Agency that this compound, used to control weeds in corn, could contaminate surface water and groundwater, accumulate in the environment and potentially damage irrigated vegetable crops and other non-target plants.

"In early 2002, the department was again asked to allow the registration and sale of Balance Pro herbicide in Wisconsin. We assembled an advisory committee, prepared a draft environmental impact statement that assessed the risks and benefits of the product, and offered it for public comment," explained Jim Vanden Brook, water quality section chief.

"Our final decision was that Balance Pro could be used in Wisconsin but only with additional product restrictions," Vanden Brook said. "These restrictions were necessary to protect our resources in Wisconsin. We based our decision on comments from the advisory committee, other interested parties and the EPA."

The restrictions include:

• Prohibiting use in eight Wisconsin counties and the Lower Wisconsin River Valley, totaling about 1 million acres.

• Prohibiting use on other fields determined to be more susceptible to groundwater contamination due to soil characteristics and shallow depth to the groundwater.

• Prohibiting use in tile-drained fields, where studies indicate residues of the compound and its breakdown product are likely to move to the tile and subsequently enter surface water.

• Environmental monitoring of surface water and groundwater in areas where Balance Pro is applied.

Bayer CropScience stated in a letter to the department that the company had concerns about the additional restrictions and considered them unreasonable. Bayer declined the opportunity to register the product for use in Wisconsin. Balance Pro is currently available in 18 other states.

"The added requirements carried a cost for Bayer CropScience," Vanden Brook explained. "This would include one time installation costs for surface water monitoring stations and groundwater monitoring wells which we estimate at $100,000. In addition, there would be annual costs for sampling, laboratory analysis as well as payments to farmers for access to the monitoring wells." Vanden Brook added, "We recognized that Balance Pro would provide another weed control tool for corn growers, but the restrictions and conditions were needed to protect all of Wisconsin agriculture and our natural resources."

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