On August 7, 2019, the U.S. Environmental Protection Agency (“EPA”) announced that it had determined that cancer warnings placed on glyphosate (“Roundup®)” labels in compliance with California’s Safe Drinking Water and Toxic Enforcement Act of 1986, known as Proposition 65, are misleading, since EPA does not recognize the data used to determine that glyphosate is a potential carcinogen. In a letter to glyphosate registrants, EPA stated that the presence of such a misleading statement on a pesticide label renders the product misbranded, and has ordered registrants to file proposed amended labels removing the Proposition 65 statement.

The determination that glyphosate is a potential carcinogen was made by the International Agency for Research on Cancer (“IARC”), a unit of the World Health Organization. That determination in turn triggered an automatic classification as a carcinogen under Proposition 65, thereby triggering the obligation to place a cancer warning on glyphosate labels. EPA has disagreed with the IARC classification since it issuance. It issued its revised Evaluation of Carcinogenic Potential on December 17, 2017, and in April 2018, issued its final determination that glyphosate does not pose a threat of cancer.

Industry brought a successful challenge to the automatic listing, and secured a preliminary injunction preventing California from enforcing the label notice requirement.  See National Association of Wheat Growers v. Zeise,  309 F. Supp. 842 (EDCA February 26, 2018).  Notwithstanding the lack of enforcement, a number of labels already bore the Proposition 65 notice, which, given the nature of pesticide label regulation, cannot simply be removed.

It remains undetermined how the label amendment process will play out. The EPA letter simply requested that a proposed amended label be submitted, without specifying whether a notification pursuant to EPA Pesticide Registration Notice 98-10 will suffice, or whether a formal amendment is required. Either way this process is bound to prove cumbersome for affected glyphosate registrants.