BREAKING NEWS: Dow Voluntarily Withdraws Dursban Uses

Dow AgroSciences has reached a "memorandum of agreement" with the U.S. Environmental Protection Agency to voluntarily withdraw chlorpyrifos from most uses in and around residences. The announcement came a day before the EPA is scheduled to hold a technical briefing in which it is expected to say that all urban pesticide uses of chlorpyrifos exceed the Agency’s level of concern. The EPA briefing begins today at 2 p.m.

Dow AgroSciences will begin monitoring a plan to deplete the existing supply of chlorpyrifos and remove it from the distribution chain to urban lawn and landscape contractors and pest control operators, among others.

Chlorpyrifos is the active ingredient in Dursban insecticide and is used in hundreds of products worldwide.

According to Mike Shaw, Dow AgroSciences’ global policy leader for chlorpyrifos, all outdoor residential uses, except for fire ant mounds and mosquito control will be eliminated as well as all outdoor, non-residential uses except for golf courses and roadside medians. Applications of chlorpyrifos to these outdoor areas cannot exceed a maximum of one pound of active ingredient per acre.

All emulsifiable concentrate formulations will be labeled as restricted use pesticides.

By the end of 2001, no distribution or sale of chlorpyrifos will take place.

The only good news, from Dow AgroSciences’ perspective, to come out of the assessment was that restrictive re-entry intervals in nurseries and greenhouses were not substantially changed.

"The EPA released its revised risk assessment and the news is worse than the preliminary assessment released in October," Shaw said. "This is based on no new toxicological information, but in how the EPA applies its science policies for this compound."

This is the first significant product-related decision impacting urban applicators since the enactment of FQPA in 1996 which charged the EPA with reviewing hundreds of pesticides used in agriculture and urban environments. The law is designed to protect children, in particular, from the toxic effects of pesticides.

Essentially, the downfall for chlorpyrifos was the result of a more restrictive revised risk assessment implemented by the EPA, which includes a 10-time uncertainty safety factor. The EPA rejected all human data studies – a reversal of the agency's long-standing policy – and added an uncertainty factor extrapolated to humans, Shaw said.

Dow AgroSciences officials maintain that the safety factor introduced by the EPA is not used anywhere else in the world and that the relevancy of the studies is highly questionable because the dose levels are thousands of times higher than real-world experiences.

"Under the preliminary risk assessment, potential risks associated with ready-to-use products, granular turf applications and turf treatments were manageable," Shaw said. "A revised risk assessment results in residual risk of cancer for all users of chlorpyrifos in and around the home."

Industry experts agree that this "scientific" review will now be applied to all organophosphates under review.

The EPA received more than 4,000 letters during the traditional public comment period. Of those, 3,700 were in support of chlorpyrifos (from university experts, user organizations and user groups), while only 300 were in opposition, the majority of which were form letters.

Disappointed officials from Dow AgroSciences reached these conclusions regarding the EPA risk assessment review:

• The EPA rejected the opinions and recommendations of the scientific community.
• The EPA's science policies are inconsistent with regulator authorities worldwide.
• Many scientific policy choices made by the EPA have nothing to do with FQPA.
• The EPA listens to opinions and needs of the user community only when they decide it's in their political interests.

Dow AgroSciences, which has invested more than $100 million in data collection on chlorpyrifos, said the safety of chlorpyrifos remains the same, "but we're dealing with a new set of rules in the United States."

For the initial reporting of the EPA's scheduled risk assesment of Dursban, please click here:
EPA To Announce Dursban Risk Assessment, Dow Responds.

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