EPA Concludes Chlorpyrifos Poses no Endocrine Disruption Risks

07/01/2015 -

Following review of a battery of new studies and completion of a “weight of evidence” assessment, EPA has concluded that chlorpyrifos poses no endocrine disruption risks and is recommending no further testing.

Chlorpyrifos and more than 60 other pesticides were selected by EPA several years ago to be the first products included in the Agency’s “Endocrine Disruptor Screening Program”. Products were selected for the program based on their volume of use and potential for applicators and others to be exposed during and following application. Dow AgroSciences and other manufacturers of chlorpyrifos completed 11 new guideline studies in response to EPA’s data call-in and submitted them, along with a “weight of evidence” assessment, during 2012. Based on a thorough review of this new information along with existing studies on file with the Agency, EPA has in its assessment published on June 29 concluded that “chlorpyrifos demonstrates no convincing evidence of potential interaction with the estrogen, androgen, or thyroid pathways”. EPA further recommended that no further, Tier 2 testing was required for the product.

Extensive research has previously demonstrated that chlorpyrifos exposures from authorized uses fall well within protective, independent health-based standards established by EPA and other regulatory authorities as safeguards against reproductive, developmental and other long and short-term adverse effects. This new battery of EPA-required screening studies further confirms these findings and eliminates any potential concerns related to interaction of chlorpyrifos with androgen, estrogen or thyroid systems in humans, fish, birds, or other wildlife.

Link to the full EPA report: EDSP: Weight of Evidence Analysis of Potential Interaction with Estrogen, Androgen or Thyroid Pathways: Chlorpyrifos

Link to additional information about EPA’s Endocrine Disruptor Screening Program.

Related: Human Health » Protecting People » Toxicology




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