The United States Environmental Protection Agency is taking the next step in its regulatory review of the active substance chlorpyrifos.

What is Chlorpyrifos?

It is an insecticide used for a wide variety of agricultural and non-agricultural uses. Widely used in agricultural pest control mainly in soybean, corn, wheat, and sunflower crops.

EPA has proposed measures to reduce the risks identified in the agency’s September 2020 draft risk assessments to better protect human health and the environment. As described in the proposed interim decision (PID), EPA proposes the following:

  • Label amendments limiting application to address potential drinking water risks of concern.
  • Additional personal protection equipment and application restrictions to address potential occupational handler risks of concern.
  • Spray drift mitigation, in combination with the use limitations and application restrictions identified to address drinking water and occupational risks, to reduce exposure to non-target organisms.

The PID presents proposed mitigation with the 10-fold (10X) Food Quality Protection Act (FQPA) Safety Factor, reflecting the uncertainties around doses that may cause pre- and post-natal neurodevelopmental effects. Under FQPA, EPA evaluates new and existing pesticides to ensure they can be used with a reasonable certainty of no harm to infants, children, and adults. EPA is required to consider the special susceptibility of children to pesticides by using an additional 10X safety factor unless adequate data are available to support a different factor. EPA additionally included a FQPA factor of 1X to reflect the range of potential risk estimates of chlorpyrifos, as illustrated in the September 2020 draft risk assessments.

Following publication of the PID in the Federal Register, public comments are accepted for 60 days on both the September 2020 draft risk assessments and the PID. By maintaining the comment period for both actions at the same time, the public will have access to more information and be able to provide more informed and robust comments.

EPA will also consider the input and recommendations from the September 2020 FIFRA Scientific Advisory Panel (SAP) meeting once it releases its report in December 2020. Depending on the SAP’s conclusions, EPA may further revise the human health risk assessment. After a thorough review of the best available science and carefully considering scientific peer review and public comments, EPA will then determine next steps in the registration review process for chlorpyrifos.