The federal Environmental Protect Agency has tossed another petition calling for a ban on the agricultural pesticide chlorpyrifos.
Two years ago, EPA Administrator Scott Pruitt denied requests fo revoke all tolerances or maximum residue levels for food and cancel all chlorpyrifos registrations.

EPA is once again allowing farmers to continue using the pesticide in their fields under strict label instructions for its use. Chlorpyrifos was banned for home use almost 20 years ago. Until then it was used on residential lawns and golf turf as a structural termite control agent.

Farmers have used it to control leafage and ground insects since Dow Chemical first registered it for use in the United States. USDA reports chlorpyrifos assists in growing as many as 50 kinds of crops.

Secretary of Agriculture Sonny Perdue praised EPA for once again keeping chlorpyrifos available on the farm. “For more than 50 crops, chlorpyrifos is the only line of defense and a cost-effective crop protection tool for farmers,” Perdue tweeted out. “We appreciate the @EPA’s support of American farmers and producers in its commitment to fact-based regulatory oversight of crop protection tools.”

EPA again found the scientific evidence isn’t strong enough to justify completely removing the pesticide from the market. Chlorpyrifos’ registration, however, is coming up for a complete review with a statutory deadline of 2022.

Issues raised in the failed petitioners in the past few years will be a be re-visited during that review, including some research that has linked chlorpyrifos to causing brain damage in children.

Activist groups like Earthjustice, claim the scientific evidence that chlorpyrifos harms children’s brains is “overwhelming.” Whether that damage occurs at the residual levels that might occur in fresh fruits and vegetables is likely another questions.

Those who do want chlorpyrifos banned whether they wish to participate in EPA review, take the issue to federal court or both.

States bans of chlorpyrifos are occurring in New York State and Hawaii. New York’s ban takes effect on Jan. 2, 2020 with use on apple tree trunks extended for an extra year. And Hawaii’s bans the bug killer beginning in 2021. Other states may follow on their own.

EPA’s previous assessment found dietary and drinking water risks for the current uses of chlorpyrifos. But it put off the scientific review of neurodevelopmental effects the 2022 study.

It is possible under the current label uses that chlorpyrifos residues on food crops can exceed the safety standard under the federal Food, Drug, and Cosmetic Act (FDCA). And there is a risk to workers who mix, load, and apply chlorpyrifos on the fields. Water exposure from both non-food and food use is also a concern.

The Obama administration in October 2015 moved to revoke all food residue tolerances for chlorpyrifos. The action came in response to a petition filed by the National Resources Defense Council and the Pesticide Action Network North America.

USDA and the National Association of State Departments of Agriculture objected to EPA’s methodology. So did the federal Scientific Advisory Panel (SAP), which is set up under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).

The SAP provides the EPA Administrator with advice on pesticides and pesticide-related issues.