A hot topic of late is the so-called Proposition 65 “naturally occurring” exemption.  This is due largely to the addition of pulegone to the Prop 65 list in April 2014.  Pulegone is a naturally occurring chemical found in many essential oils, including peppermint oil. With warnings required on products containing pulegone that cause significant exposures as of April 18, 2015, Prop 65 forums have been peppered with questions about compliance for cosmetic and food products. Unfortunately, the naturally occurring exemption is unlikely to solve many Prop 65 pulegone problems.

The naturally occurring exemption

Regulations promulgated by OEHHA define the naturally occurring exemption, stating that “human consumption of a food shall not constitute an ‘exposure’ for purposes of … [Proposition 65] to a listed chemical in the food to the extent that the person responsible for the exposure can show that the chemical is naturally occurring in the food.”

A chemical is “naturally occurring” if “it is a natural constituent of a food, or if it is present in food solely as a result of absorption or accumulation of the chemical which is naturally present in the environment in which the food is raised, or grown, or obtained….” If a product is something other than food, the exemption may apply if the chemical “was a naturally occurring chemical in food, and the food was used in the manufacture, production, or processing of the consumer product.”

The challenge

The problems with the naturally occurring exemption are twofold.

First, OEHHA’s regulations place a number of conditions on use of the exemption:

  • A chemical is naturally occurring only to the extent that the chemical did not result from any known human activity.
  • Determining the naturally occurring level of a chemical in a food typically requires demonstrating the “natural background level of the chemical in the area in which the food is raised, or grown, or obtained, based on reliable local or regional data.”
  • A chemical is naturally occurring only to the extent that the chemical did not result from any known human activity (e.g., the addition of chemical fertilizers).
  • When a chemical naturally occurs in a food as a contaminant, the exemption applies only if the contaminant was unavoidable despite good agricultural or manufacturing practices, and quality controls must be used to keep contaminants to the lowest level currently feasible.

Second, a defendant bears the burden of proving the naturally occurring exemption and addressing the various conditions, as applicable. Each of these issues is open to challenge from plaintiffs in litigation. A company could evaluate a food product and decide not to warn based on the exemption, only to have a judge disagree with that finding after protracted and costly litigation. This is the situation with pulegone – a decision not warn for a product containing peppermint or other essential oils containing pulegone is a roll of the dice, especially if the essential oil is added to the product. The only safe bet for reliance on the exemption is methanol resulting from naturally occurring pectin in fruit, which OEHHA has directly addressed in interpretive guidance.