Dioxin Developments

February 16, 2017 | Commercial Litigation | Complex Torts & Product Liability

Court Ruling Moves California Closer to Requiring Warning Label on Glyphosate

A tentative ruling by a California judge has moved state regulators closer to requiring a warning label on glyphosate, the main ingredient in the Monsanto product, Roundup.


In 1986, California voters adopted Proposition 65, more formally known as the Safe Drinking Water and Toxic Enforcement Act of 1986. In two ways, Proposition 65 regulates chemicals officially listed by California as having a one in 100,000 chance of causing cancer over a 70-year period or birth defects or other reproductive harm. First, Proposition 65 prohibits companies from knowingly discharging listed substances into drinking water sources, or onto land where the substances can pass into drinking water sources. Second, the statute prohibits businesses from knowingly exposing individuals to listed substances without providing a clear and reasonable warning.

The list must be updated at least once per year. First published in 1987, it now contains about 800 chemicals.

One way that chemicals can be added to the list is under the California Labor Code. In particular, chemicals can be added to the list if they meet certain criteria and are identified in the Labor Code as causing cancer or birth defects or other reproductive harm.

In September 2015, the California Environmental Protection Agency Office of Environmental Health Hazard Assessment (“OEHHA”) proposed to add glyphosate to the Proposition 65 list via the Labor Code listing mechanism.

The OEHHA explained that California Labor Code Section 6382(b)(1), incorporated into Proposition 65, required that certain substances identified by the International Agency for Research on Cancer (“IARC”) be listed as known to cause cancer under Proposition 65.

In March 2015, IARC had classified glyphosate as “probably carcinogenic to humans.”

Given that decision, the OEHHA said, it could “not consider scientific arguments concerning the weight or quality of the evidence considered by IARC” when it identified glyphosate as “probably carcinogenic to humans” in connection with its decision making under Proposition 65.

Monsanto sued the OEHHA, arguing among other things that it had engaged in an unconstitutional delegation of authority by allowing IARC to determine the chemicals to be added to the list of possible cancer-causing agents.

The Court’s Decision

Late in January, the court issued its tentative ruling, in Monsanto Co. v. Office of Environmental Health Hazard Assessment, No. 16 CE CG 00183, in favor of the OEHHA, indicating that it would issue a final decision in its favor.

The court found that the Labor Code listing mechanism did “not constitute an unconstitutional delegation of authority to an outside agency” because the voters and the legislature had established the basic legislative scheme, made the fundamental policy decision with respect to listing possible carcinogens under Proposition 65, and “then allowed the IARC to make the highly technical fact-finding decisions with regard to which specific chemicals would be added to the list.”

Next, the court rejected Monsanto’s contention that the Labor Code listing mechanism violated the due process clauses of the California and U.S. Constitutions because Monsanto’s property interest in its Roundup trademark, its business goodwill, and its reputation would be damaged if glyphosate were listed as a possible cause of cancer based on IARC’s decision. The court simply reasoned that the OEHHA’s decision was “not subject to procedural due process claims” because it was “a quasi-legislative act.”

The court also rejected Monsanto’s other arguments, indicating that it intended to grant the OEHHA’s motion for judgment on the pleadings and sustain the demurrer as to Monsanto’s first amended petition and complaint.

The court also declared that it intended to deny leave to amend the pleadings, as there did “not appear to be any chance” that Monsanto could amend its complaint to state valid claims under any of theories it relied on.

For further information, please contact James V. Aiosa, Paul V. Majkowski, Lawrence S. Han, or your regular Rivkin Radler attorney.

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