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Obama EPA’s last-minute moves on chemicals

Agency releases slew of actions on pesticides, toxics, and nanomaterials

by Britt E. Erickson , Jessica Morrison
January 18, 2017 | A version of this story appeared in Volume 95, Issue 4

Credit: Shutterstock

Just days before President Trump took office, EPA proposed to ban or restrict two chemicals—methylene chloride and N-methylpyrrolidone—in paint removers.
Metal scraper removing bubbling green paint.
Credit: Shutterstock

Just days before President Trump took office, EPA proposed to ban or restrict two chemicals—methylene chloride and N-methylpyrrolidone—in paint removers.

In a last minute push to get several rules out before the Trump Administration took control, the Obama Environmental Protection Agency released a series of regulations, proposals, and policies affecting chemicals. The actions involve pesticides, toxic solvents, and nanoscale materials.

Many of the moves had long been in the works, including three pesticide-related actions announced on Jan. 12. In one, EPA expanded the use of Dow AgroScience’s herbicide Enlist Duo, a combination of glyphosate and 2,4-D. The controversial mixture can now be sprayed on cotton that has been genetically modified to tolerate the chemicals, as well as on corn and soybeans in 34 U.S. states.

Environmental groups are infuriated by EPA’s decision to expand the use of the herbicide mixture. EPA first approved Enlist Duo for use on corn and soybeans in a handful of states in 2014, but then found information in a patent application that suggested synergistic effects would increase the product’s toxicity. EPA subsequently asked a federal court to overturn the approval.

In November 2016, after receiving additional data from Dow, EPA said that it agrees with the company that the two active ingredients do not amplify each other’s toxicity.

Earlier this month, the Center for Biological Diversity, an environmental group, submitted a Freedom of Information Act request seeking data from four unpublished studies by Dow that EPA relied on in making its decision. “EPA’s about-face on Enlist Duo was very sudden and came only after it received a handful of unpublished studies on the pesticide from Dow,” says Nathan Donley, a senior scientist at the center.

In a separate move, EPA released draft assessments of four neonicotinoid pesticides, finding that some spray applications pose potential risks to bees and other pollinators. The agency also released voluntary guidelines for labeling all moderately to highly toxic pesticides to protect pollinators during blooming times. Granting the requests of pesticide makers, EPA eased restrictions for some applications.

The part of EPA that oversees the safety of chemicals in household and industrial products also was active during the last days of the Obama Administration. On Jan. 13, the agency released three proposals intended to ensure that EPA meets several June deadlines under the revised Toxic Substances Control Act (TSCA).

One of the proposals would require chemical manufacturers and importers to notify EPA of chemicals they are producing. Another would establish a process for EPA to choose chemicals for risk evaluation. The third would set out a process for EPA to evaluate chemicals’ risks.

Photo shows a tractor spraying a field of small vegetation with a line of palm trees and mountains in the background.
Credit: Jeff Vanuga, USDA Natural Resources Conservation Service
EPA’s actions on pesticides affect neonicotinoids and a combination of glyphosate and 2,4-D.

Chemical makers and environmental groups are praising EPA for proposing those processes in time to meet the June deadlines that Congress mandated for finalizing them under the new TSCA. But the American Chemistry Council, which represents chemical manufacturers, is urging the agency to provide clearer criteria for identifying low- and high-priority chemicals.

“The risk-based prioritization rule must do more than address procedural requirements,” ACC says. “It must explain how statutory decisions will be based on the best available science and the weight of the scientific evidence.”

EPA also released two proposals that would ban certain uses of three common solvents under TSCA. One proposal would prohibit trichloroethylene in vapor degreasing. The other would bar the use of methylene chloride in paint removers and ban or restrict N-methylpyrrolidone in paint removers. EPA says it has identified unreasonable human health risks associated with such uses. The fate of these proposed rules under the Trump Administration is uncertain.

In yet another action, EPA on Jan. 12 finalized a long-awaited data collection rule for commercial nanoscale materials. The regulation requires manufacturers of certain new and existing nanomaterials to report data that includes chemical identity, manufacturing methods, production volume, and available health and safety information. The one-time reporting rule applies to commercial materials with dimensions approximately 1–100 nm at any production volume.

The rule is not meant “to conclude that nanoscale materials will cause harm to human health or the environment,” EPA says. The agency says the effort will help it decide if it needs more data about nanoscale materials for risk reviews under TSCA.

“This basic rule has been a very long time coming,” says Richard Denison, a lead senior scientist at the Environmental Defense Fund, an advocacy group. “EPA can at last begin to get basic risk-relevant information needed to make sound decisions about which materials and uses present concerns and which do not.”



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