EPA versus the State of California: An Important Glyphosate Update

Glyphosate is a widely used herbicide perhaps best known for being the active ingredient in the blockbuster weed killer Roundup®.  As many readers are probably aware, Roundup® is currently the subject of both state and federal litigation in which numerous plaintiffs allege that using Roundup® caused their cancers.  Whether Roundup® is in fact carcinogenic has been the subject of international consideration.  Here in the United States, we now find the State of California and the United States Environmental Protection Agency (“EPA”) on opposing sides of the issue.

Glyphosate was first registered in the United States in 1974.  For many years, the EPA and other international bodies have essentially affirmed glyphosate’s safety.  However, in March 2015, the World Health Organization’s International Agency for Research on Cancer (“IARC”) classified glyphosate as “probably carcinogenic” to humans.  In March 2017, the European Chemicals Agency (“ECHA”) announced recommendations from a risk assessment of glyphosate which was performed by its Committee for Risk Assessment.  That committee did not find evidence implicating glyphosate as being carcinogenic.  In the United States, the EPA continued to maintain its position that glyphosate poses no significant cancer risks to the generally public. 

Despite EPA’s position, in March 2017, California adopted IARC’s classification of glyphosate as a carcinogenic and gave notice of its intention to add glyphosate to its list of chemicals known to the State of California to cause cancer.  To understand exactly what California was doing, you need not understand California’s Proposition 65.  On November 4, 1986 voters in California enacted a ballot measure known as Proposition 65 or the Safe Drinking Water and Toxic Enforcement Act of 1986.  Proposition 65 requires the state to maintain and update a list of chemicals known to the state to cause cancer or reproductive toxicity.  The Office of Environmental Health Hazard Assessment (“OEHHA”) within the California Environmental Protection Agency is the lead state agency responsible for the implementation of Proposition 65.  Proposition 65 requires businesses to provide a warning to Californians about exposures to chemicals listed as known to the State of California to cause cancer or reproductive toxicity.  This warning can also include labeling products with a Proposition 65 warning.

On July 7, 2017, the State of California added glyphosate to its list of chemicals known to the State of California to cause cancer.  By adding glyphosate to that list, OEHHA adopted a position directly contrary to that of EPA as to glyphosates carcinogenicity.  Not surprisingly, this action was challenged by way of a lawsuit for declaratory and injunctive relief filed in federal court in California.  One of the arguments raised in the lawsuit is that requiring a Proposition 65 warning for exposure to glyphosate violates the First Amendment because it requires businesses to make a misleading statement, namely, that glyphosate causes cancer.

On February 26, 2018, a federal judge in the Eastern District of California in National Association of Wheat Growers et al. v. Zeise issued a preliminary injunction barring California from enforcing Proposition 65’s warning requirement for glyphosate while the case continues in court.  In issuing the injunction, the court found that plaintiffs established that they are likely to prevail on their First Amendment claim.  Litigation in that case is continuing and the injunction remains in place at this time, meaning that OEHHA cannot presently enforce Proposition 65’s warning requirements for glyphosate.

On August 8, 2019, the EPA issued a press release stating that EPA will no longer approve product labels claiming glyphosate is known to cause cancer.[1]  EPA explained that stating that glyphosate causes cancer is a false claim which does not meet the labeling requirements for the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”).  The press release went on to state that Proposition 65 has led to misleading labeling requirements because it misinforms the public about the risks they are facing.

On August 12, 2019, OEHHA responded issuing its own statement objecting to EPA’s characterization of glyphosate’s carcinogenicity as a “false claim” and accusing the EPA of being disrespectful of scientific process in dismissing any warning based on IARC’s determinations.[2]

Whether EPA will respond to OEHHA’s statement remains to be seen.  But one thing is for sure, all parties involved in the pending personal injury lawsuits brought by plaintiffs claiming that their cancer was caused by glyphosate will be watching this battle closely.  We will be sure to bring you updates as they develop.


[1] https://www.epa.gov/newsreleases/epa-takes-action-provide-accurate-risk-information-consumers-stop-false-labeling

[2] https://oehha.ca.gov/media/downloads/proposition-65/general-info/glyphosatestatement08122019.pdf

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Products Liability Prevention & Defense
Our attorneys represent foreign and domestic designers, manufacturers, and distributors of a diverse array of products, from food and drugs to industrial equipment and building materials. We help clients respond to major personal injury and property damage claims in the form of single-product cases, class actions, mass torts, and multidistrict litigation, as well as all types of congressional, regulatory, or criminal investigations. Our team works closely with corporate counsel to minimize a company’s overall liability and establish efficient protocols for fielding claims and advise on labeling, marketing, manuals and instructions, supply and distribution contracts, and insurance and indemnification issues.
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