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OEHHA Proposes No Significant Risk Level for Glyphosate

On March 28th, 2017, the Office of Environmental Health Hazard Assessment (OEHHA) decided that glyphosate will be listed under California’s Proposition 65 as a carcinogen. The effective date of the listing will depend on the outcome of an appellate decision as described further below. OEHHA has also proposed adopting a Proposition 65 No Significant Risk Level (NSRL) of 1100 micrograms per day for glyphosate. Comments regarding the proposed NSRL must be received by OEHHA on May 22, 2017 by 5:00 pm. All comments received will be posted on the OEHHA website after this public commenting period closes.

Under Proposition 65, businesses are prohibited from knowingly and intentionally exposing individuals to listed chemicals without a clear and reasonable warning, unless an exemption applies. The law also prohibits the knowing discharge of listed substances into sources of drinking water. Businesses are exempted from the warning requirement if the alleged exposures are occurring at a level below the regulatory warning level for the specific listed chemical-i.e., the safe harbor level. For carcinogens, the warning level is known as the No Significant Risk Level.

Glyphosate is a chemical used commonly as an herbicide. Agriculture giant, Monsanto, uses glyphosate as the active ingredient in Roundup, a weed killer the company manufactures. OEHHA originally proposed listing glyphosate as a carcinogen in the fall of 2015. In January 2016, Monsanto challenged OEHHA’s then-proposed listing of the substance in a lawsuit filed in Fresno County Superior Court. Although the court ruled in favor of OEHHA earlier this year, Monsanto is appealing this decision and asking the Court of Appeal to block glyphosate’s listing under Proposition 65 while the appeal is pending. Thus, until the Court of Appeal renders its decision, it is not known when (if ever) the glyphosate listing will become effective. Therefore, stakeholders are put in the odd position of providing comments on a proposed NSRL for a chemical that may never be listed at all.

The Proposition 65 warning requirement goes into effect one year after the chemical listing. Entities in a product’s supply chain may be obligated to provide a warning if the exposure to the chemical exceeds the warning level. Businesses can use the safe harbor level to help determine when a warning needs to be provided. With so many unknown variables in the possible listing of glyphosate and the chemical’s NSRL, businesses who sell and use glyphosate-containing products should remain up to date on developments.

This article was researched and written by Cecilia Grimaldi. Ms. Grimaldi is a research assistant at Grimaldi Law Offices where she drafts summaries of regulatory developments pertaining to chemical manufacturing and use. She is currently a third year at Cal Poly, San Luis Obispo, though she is originally from San Francisco. She will be graduating this spring with a degree in English and Psychology.

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Ms. Grimaldi maintains a diverse environmental law practice focusing on chemical and product regulation and litigation defense. Her practice areas include Proposition 65, California's Safer Consumer Products Regulations, California's Rigid Plastic Packaging Container Act and the federal Toxic Substances Control Act. Ms. Grimaldi graduated from the University of California Hastings College of the Law magna cum laude and holds a Bachelor of Science Degree in Bacteriology from University of California, Davis. Prior to attending law school, she worked as a research assistant in laboratories at the University of California, San Francisco Cancer Research Institute and at the University of California, San Francisco School of Medicine.