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March 11, 2016

EPA Defends Conditional Nanosilver Registration

Lynn L. Bergeson Carla N. Hutton

On March 8, 2016, the U.S. Environmental Protection Agency (EPA) filed its brief in the U.S. Court of Appeals for the Ninth Circuit responding to two petitions for review of its conditional registration of a nanosilver pesticide product. NRDC v. EPA, No. 15-72308. The Natural Resources Defense Council (NRDC), as well as the Center for Food Safety (CFS) and International Center for Technology Assessment (ICTA), filed suit, asking the court to set aside EPA’s final order granting a conditional registration for a nanosilver-containing antimicrobial pesticide product named “NSPW-L30SS,” or “Nanosilva.”

In the consolidated case, EPA argues that when the petitioners commented on EPA’s proposed decision, they failed to raise most of the arguments they brought before the court, denying EPA an opportunity to address those issues. EPA provides the following summary of the issues presented:

  1. Whether substantial evidence supports EPA’s finding that the applicant Nanosilva lacked sufficient time to submit the required data, when EPA first imposed requirements on Nanosilva in the final order granting registration, and when data requirements in another entity’s registration did not apply to Nanosilva and other prior EPA actions never imposed the same requirements; and
  2. Whether EPA’s public-interest finding is supported by substantial evidence when data and other information in the record demonstrate that use of the pesticide could reduce the amount of silver in the environment and risks associated with silver.

EPA argues that it properly determined that Nanosilva had insufficient time to generate data. According to EPA, it imposed new data requirements simultaneously with its grant of NSPW-L30SS’s registration, and Nanosilva did not have sufficient time to satisfy those requirements. EPA rejects petitioners’ assertion that EPA imposed the data requirements at one of three earlier points: (1) in 2011 when it required data as a condition to AGS-20’s registration; (2) in 1984 when it promulgated regulations for data requirements; or (3) in 2010 when it communicated with Nanosilva about certain data. EPA states that conditioning HeiQ’s AGS-20 registration on the submission of certain data “does not ‘first impose’ those requirements on everyone else,” and that “[t]his interpretation is entitled to Chevron deference.” According to EPA, the 1984 regulations “require substantively different data from what EPA demanded of Nanosilva in 2015.” In its 2010 communications with Nanosilva, EPA states that it recommended the submission of additional data, but different data than what it “demanded” in 2015.

According to EPA, it “properly found that use of NSPW-L30SS is in the public interest because it could reduce the environmental silver load and risks associated with silver.” EPA cites evidence in the record showing that NSPW-L30SS’s nanosilver is applied at much lower rates than conventional silver; that NSPW-L30SS is expected to release silver ions at a controlled rate; and that the amount of silver that leaches from material treated with NSPW-L30SS into the environment is so low that it cannot be detected by measuring instruments. According to EPA, it further confirmed its conclusion after considering nanosilver’s toxicity. EPA rejects petitioners’ arguments regarding mobility, stating that petitioners misunderstand EPA’s review of leaching data. EPA states that its assumption that the use of NSPW-L30SS by manufacturers who start silver treatment after registration will not increase the overall environmental silver load needed no substantiation. Nothing in the record supports the petitioners’ claim, and EPA “was not obliged to embark on a wild goose chase to prove a negative proposition.” EPA describes petitioners’ final two arguments as “equally unconvincing.” EPA states: “One nonsensically demands that EPA’s public-interest finding be made with absolute certainty. The other urges the Court to review an allegation that EPA failed to comply with its non-binding guidance, an invitation that this Court has long rejected; moreover, the underlying argument lacks merit.” EPA asks the court to deny the petitions.