The U.S. EPA says it needs more time to decide whether to cancel the registration of chlorpyrifos and revoke all of the pesticide's food tolerances, as requested in a petition.

  In a status report filed with 9th Circuit Court of Appeals, the agency asked the court to give it until June 30, 2017, to respond to the petition from Pesticide Action Network North America (PANNA). Last December, the 9thCircuit ordered EPA to make a decision on the petition by Dec. 30. 

  EPA said it needs time to review a pending report from a Scientific Advisory Panel (SAP) that is looking at EPA's use of epidemiological data in determining what action to take. At a meeting in April, many of the SAP members expressed doubt about the use of blood data from an epidemiological study conducted at Columbia University.

  Using the epidemiological study would be a departure from the way the agency has historically estimated chlorpyrifos risks, using acetylcholinesterase inhibition. Employing the latter approach, EPA proposed to revoke food tolerances for chlorpyrifos on Nov. 6.

  But “to EPA's surprise, the panel advised against the new approach,” the agency said in its status report. “This was somewhat of a departure from the conclusions and recommendations of a 2012 (SAP), on whose advice EPA conducted a series of dose reconstruction and modeling analyses to build a scientific foundation in order to utilize the epidemiological data.”

  The panel, however, “also raised concerns” that the use of acetylcholinesterase inhibition to determine exposure levels may not sufficiently protect public health. 

  “In short, the panel seemed to recommend that EPA develop a hybrid approach but did not provide specific suggestions for doing so” at its April meeting, EPA said.

If forced to meet the Dec. 30 deadline, EPA said it would not be able to consider public comments on the panel's conclusions or on a drinking water assessment that was completed a year ago.

  “Six months represents a modest extension that ensures that EPA has the time necessary for addressing both the public process and extremely complex science associated with this action while holding EPA to an expeditious timeframe for completing an action that relates to the protection of public health,” the agency said.

  PANNA and the Natural Resources Defense Council, whose lawsuit resulted in the court order, have until July 29 to respond to EPA's request. Earthjustice attorney Patti Goldman told Agri-Pulse they would probably wait until release of the SAP report at the end of July before taking a position on an extension.