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Court Affirms Lead Limits Under Proposition 65

The legitimacy of the safe harbor limits for lead exposure created by California’s Office of Environmental Health Hazard Assessment (OEHHA) has been the subject of a contentious battle for years. The California Court of Appeals for the First District recently upheld the current 0.5 microgram per day safe harbor for lead (also known as the Maximum Acceptable Dose Level, or MADL) that was set in 1989. In doing so, the Court affirmed that the state acted permissibly in establishing that exposure level for the chemical. If the Court had revoked the safe harbor, then businesses would have been required to issue a warning for any exposure to lead no matter how infinitesimal or OEHHA would be required to set a new (and possibly lower) safe harbor level.

Lead and lead products are listed under Prop 65 as chemicals known to cause cancer and reproductive toxicity. The law requires businesses to provide a warning for any product causing exposures to more than 0.5 micrograms of lead per day, which is an exceedingly rigorous threshold level. Many foods, including dietary supplements and herbal remedies, contain low doses of chemicals found in soil, plants or water, which typically includes lead. The safe harbor level of 0.5 microgram per day MADL established by OEHHA is considered considerably lower than the amount of lead naturally occurring in normal daily serving sizes of fruits, vegetables, and herbs. Section 25501 of the Prop 65 regulations allow companies to establish that the levels of listed chemicals in foods are “naturally occurring” and therefore do not count towards the chemicals’ warning triggers (0.5 micrograms per day for lead). However, the elements of this regulatory defense are, as a practical matter, almost impossible for a company to prove. Not surprisingly, this difficulty in proof means that foods are easy Prop 65 enforcement targets.

The lawsuit was initiated by a well-known Proposition 65 enforcer, Mateel Environmental Justice Foundation (Mateel), against OEHHA in 2015. Mateel sought to overturn the MADL for lead set almost three decades ago. The MADL for reproductive toxins refers to the level at which a chemical would have no observable effect even if exposure occurred at 1000 times that level.  Mateel attempted to invalidate the established MADL by contending that the MADL does not propose a standard at which no observable effect exists. However, the court found that the plaintiff did not present adequate data to support this claim.

For businesses that have relied on the safe harbor for lead, this ruling is a significant victory. As low as the current lead MADL is, a different court outcome could have resulted in a MADL even lower than 0.5 micrograms per day. If the court had ruled in favor of the plaintiff, California businesses would face considerable challenges in complying with Prop 65 and be forced to provide excessive and potentially unnecessary warnings about lead that may not pose actual dangers to consumers.

Grimaldi Law Offices has been advising clients for over 20 years on chemical and product law. For knowledgeable advice and in-depth analysis on your Prop 65 compliance obligations, contact Grimaldi Law Offices at (415) 463-5186 or email us at [email protected].

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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.