In its response to the U.S. Environmental Protection Agency (EPA) on the agency’s proposed decision to revoke food tolerances for carbofuran, the USDA agreed with corn farmers who want the proposal reconsidered. Growers consider carbofuran to be the only reliably effective postplant rootworm rescue treatment available.

In his comments, Agriculture Secretary Ed Schafer stressed the procedural difficulties of the EPA’s proposed rulemaking. Schafer argued that revoking tolerances while not banning the product itself would mean that farmers would be “in the position of potentially producing a crop with illegal residues from the legal use of a pesticide.

“This is an untenable position for the growers because they could face enforcement actions under FFDCA [Federal Food, Drug, and Cosmetic Act] if the Food and Drug Administration of the U.S. Department of Health and Human Services were to find residues on food produced after EPA revokes the tolerances for carbofuran but before EPA cancels or suspends the registration of carbofuran,” Schafer’s letter states. “The impact of such a violation could also extend beyond the grower as the commodity with a measurable residue could become embargoed at any point in the marketing chain.”

In a formal comment to the EPA late September, National Corn Growers Association (NCGA) Chairman Ron Litterer, then the organization’s president, stressed the chemical’s importance to safeguarding the nation’s corn supply.

“The corn rootworm presents a very serious problem to the nation’s corn crop and is one of the most aggressive and serious pests infesting corn today,” Litterer writes. “Rootworm larvae feed on a corn plant’s roots, which results in extensive root damage and leaves corn plants vulnerable to falling over because their root system is no longer capable of providing support or nutrients and water to the plants. Once plants are toppled due to root loss, harvesting corn becomes extremely difficult because modern combines are not designed to collect corn from fallen plants. This results in significant yield reductions, and in some cases, total yield loss.”

Litterer explains that the dietary risk assessment for carbofuran developed by EPA is based on flawed analysis and is overly conservative. “NCGA believes that the carbofuran tolerances for corn necessary to support carbofuran’s continued use on field corn as a rescue treatment should be retained because these potential residues do not pose an unacceptable risk to human health from either dietary or water exposure,” he writes.