EPA’s Most Recent (June, 2015) Status Report to the Ninth Circuit Court of Appeals on Its Progress in Responding to Activist Petition

06/29/2015 -

On June 30, 2015, the U.S. Environmental Protection Agency (EPA) filed a status report with the Ninth Circuit Court of Appeals describing the Agency’s plans to respond to an activist petition filed in 2007 seeking the cancellation of chlorpyrifos registrations and the revocation of food tolerances.1 Because EPA was ordered to file the status report before it had finalized its Revised Human Health Risk Assessment (RHHRA) in the ongoing registration review of chlorpyrifos, the Agency reserved a range of options, from denying the petition to the possibility of proposing tolerance revocations. EPA has not yet completed its consideration of the substantive comments received from stakeholders during the RHHRA public comment period, which closed April 30th.

EPA’s report was clear: the revocation action may not be necessary. EPA stated that, if its concerns are resolved, it will simply deny the petition. And in any event no proposal would even be made until April 2016. Even if such a proposal were to be made, chlorpyrifos would continue to be available well beyond the 2016 growing season.2 Opportunities for growers and other stakeholders to express their needs in the regulatory process would be provided before any final regulatory action is taken.

EPA’s drinking water assessments proposed in the RHHRA are based on hypothetical, worst-case scenario modeling of surface water runoff. EPA’s projections from the modeling run strongly contrary to a wealth of real-world water monitoring data that has been provided to the Agency.3 In addition, the Agency had not considered in their assessment a toxicological study that shows no adverse effect or hazard in the animals tested at doses far in excess of levels that could physically be present in drinking water.3 With no hazard, there is no risk.

Dow AgroSciences is strongly committed to ongoing support of chlorpyrifos for continued use by its customers worldwide. Regulatory evaluation of registered pesticides is an ongoing and essentially never-ending process. Dow AgroSciences will continue to work with the EPA to ensure the comments from Dow AgroSciences and other stakeholders are considered, EPA’s concerns are resolved, and the critical uses for chlorpyrifos are retained for many years to come.


1Pesticide opponents filed their legal action in 2007. In recent years, EPA has denied seven counts of the petition, and the court recently required the Agency to provide an update on how it intends to respond to the rest of them.

2 Under EPA’s standard rulemaking procedures, the proposal would be followed by opportunities for notice and comment for stakeholder input, which the Agency would then need to consider and respond to before issuing a final action, probably much later in the year. Any actual restrictions on the manufacture, sale or use of end-use products containing chlorpyrifos would most likely take many more months.

3Specifics on the studies: EPA has yet to consider several important submitted studies relevant to its assessment. The first one is a toxicological study demonstrating no risk from exposure to chlorpyrifos-oxon in drinking water. In that study, no hazard was found at doses seven-times the level of the product that could actually be found in drinking water based on its water solubility. Aligned with the principle EPA used in the decision of no risk from potential volatilization, “no hazard” therefore equates to no risk from potential drinking water exposures. In the second study, based on 47,000 water samples from available water monitoring surveys of community water systems on both large to small rivers and streams taken during various time periods between 1991 and 2013, statistical methods allowed the characterization of the distribution of exposures at the higher percentiles of exposure. Exposures dropped to only slightly above 10% of both the acute and chronic levels of concerns. The results matched well with exposures based on Centers for Disease Control (“CDC”) biomonitoring data.

Related: Human Health » EPA » registration review




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