Californias Prop 65 could list essential oils as carcinogens

Two common components of essential oils could potentially be listed as carcinogens under California's Proposition 65. Is this a true health concern or has the law—with its loophole for potentially frivolous lawsuits—gone too far?

In a move that perplexes natural chemistry experts, two common components of essential oils are now being considered for listing as carcinogens by the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA), charged with carrying out the state’s Proposition 65. The law, passed in 1986, aims to protecting drinking water from toxins and to reduce or eliminate chemical exposure in consumer products.

“Having analyzed essential oils for 20 years, these are simple monoterpenes that I would probably have a hard time thinking of oils that don’t have them,” said James Neal-Kababick, director of Flora Research Laboratories and adjunct faculty at Bastyr University.

“It could devastate the aromatherapy industry, or anybody who uses any kind of fragrance,” Neal-Kababick said. “Somebody put forward a request for this and they’re looking at it. Things like pine oil, lavender oil and geranium: They all have these things in there. So depending on what [the OEHHA] settles on for exposure levels, I see a potential playground for frivolous litigation.” (The public comment period ended April 10. Find more information and comments here.) 

One of the substances up for listing, beta-myrcene, is in lemon verbena, lemongrass and other oils used as a flavor and fragrance in foods and beverages, as well as cosmetics, personal care products and cleaning products. The second, pulegone, is in peppermint oil and is used in similar ways. The research behind the carcinogen concern found kidney tumors, benign and malignant, in rats and mice who’d likely had the oils injected down their throats, Neal-Kababick said.

So is there really a health concern, or have some Prop 65 exposure limits gone too far? California’s lead limits, for instance, are so low they can be almost impossible to meet for certain ingredients, said Neal-Kababick. “More and more companies, are starting to think about not selling products in California because of the litigious environment,” he sid, even though California is a major consumer of dietary supplements. “Who gets hurt in the end are consumers and the retailers who won’t be able to provide certain kinds of supplements.”

What’s your take on essential oil components being listed as carcinogens? Do you think Prop 65 sometimes goes too far in its intended consumer protection role?

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