Fewer Animals Used Under Draft EPA Pesticide Guide

By Pat Rizzuto

March 18 — Pesticide manufacturers could waive more acute dermal toxicity tests under draft guidance the Environmental Protection Agency has released as a part of a package of actions it is taking to encourage companies to use nonanimal-based testing methods to generate required toxicity data.

“Acute dermal toxicity data on product formulations offer little scientific information or public health protection,” Jack Housenger, director of the EPA's Office of Pesticide Programs, wrote in an recent letter to stakeholders. OPP reached that conclusion based on a retrospective analysis of acute oral and dermal lethality studies it and a National Toxicology Program center conducted involving data from studies of 593 pesticide active ingredients.

Based on the conclusion, the EPA announced March 17 draft guidance that would expand the ability of pesticide makers to provide acute dermal toxicity data using in vitro and computer-based modeling methods rather than experimental animals such as mice, rats and rabbits.

The agency also released a final process to explain how alternative tests that would generate data for other acute health effects could be evaluated and, following public comment, potentially used.

The draft guidance and final process could affect companies that make active ingredients for, or formulate mixtures of, conventional pesticide, antimicrobial and biochemically based pesticides.

`Significantly Reduce' Animal Use

“The Office of Pesticide Program's immediate goal is to significantly reduce the use of animals in acute effects testing,” Housenger's letter said.

More than 50 animals typically are used to generate data from a testing battery commonly called the “six-pack” acute effects studies. The six-pack includes tests designed to find the lethal dose of exposure through three different routes: oral, dermal, and inhalation. The testing battery also evaluates allergic responses of the skin and eye corrosion and irritation.

The data resulting from these tests are used to determine what protections pesticide applicators need.

“Annually we receive over 500 acute toxicity six-pack submissions,” Housenger wrote. “Although not every submission contains a complete set of studies, the potential for a substantial reduction in animal testing is clear.”

According to the Humane Society of the United States, OPP's draft guidance “will largely eliminate `lethal-dose' tests for exposure by the dermal route.”

Janet E. Collins, senior vice president of science and regulatory affairs at the pesticide makers trade association CropLife America, told Bloomberg BNA March 18 that CLA had not been able to analyze the details of the agency's proposal, final process and other actions it announced.

CropLife does support the EPA's effort to reduce the use of animals and develop validated, alternative tests that can produce more consistent and better information, she said.

Impact on Reporting Requirements

The final process OPP released describes the steps it would take to evaluate and possibly allow the use of alternative tests that may substitute for additional animal-based acute toxicity testing methods. Proposed new tests would follow a three-stage process consisting of:

  • the evaluation of an alternative test method;
  • a proposal to use, and provide public comments concerning a new test; and
  • the agency's issuance of a final policy about the proposed test.
  •  

    If the EPA approves a new test method, the information arising from the tests may be reportable under Section 6(a)(2) of the Federal Insecticide, Fungicide and Rodenticide Act if the new methods correlate to tests upon which the agency currently relies, the pesticides office said.

    According to Section (6)(a)(2) of FIFRA: “If at any time after the registration of a pesticide the registrant has additional factual information regarding unreasonable adverse effects on the environment of the pesticide, the registrant shall submit such information to the administrator.”

    Data submitted from an alternative test to comply with Section 6(a)(2) “will not necessarily dictate regulatory decisions or label amendments,” the agency said. “EPA will consider reported data in the context of the full range of data previously submitted in support of the registration, applying a weight of evidence approach.”

    Additional Actions; Initial Reactions

    Housenger's letter referred to several other actions OPP is taking to encourage the use of alternative toxicity tests to generate data about acute exposures.

    For example, the office is exploring ways it could use toxicity categories established under the United Nation's Globally Harmonized System of Classification and Labeling (GHS) system for the hazard portion of the pesticide label.

    People for the Ethical Treatment of Animals and the Physicians Committee for Responsible Medicine joined the Humane Society in commending the agency for its actions to reduce the use of animals in regulatory tests.

    The information the EPA has sought through such tests is valuable, the Physicians Committee said.

    “Understanding the potential effects of chemicals on humans for these serious effects is important to protecting workers and the public, and it is essential that regulatory requirements keep pace with scientific progress.”

    However, “alternative methods can save time and resources and often use human tissues, offering more accurate predictions of human toxicity. Waiving tests which do not add value to a risk assessment saves time and resources that can be used to investigate more relevant data,” the committee said.

    To contact the reporter on this story: Pat Rizzuto in Washington at prizzuto@bna.com

    To contact the editor responsible for this story: Larry Pearl at lpearl@bna.com

    For More Information

    The EPA's draft guidance, final process and other related documents are available at http://tinyurl.com/zqne5k3.

    Comments on the draft guidance, due May 16, should be marked Docket No. EPA-HQ-OPP-2016-0093 and filed via http://www.regulations.gov.