On March 27, 2015, the Office of Environmental Health Hazard Assessment added beta-myrcene to the California Proposition 65 chemical list. Under Proposition 65, products containing newly listed chemicals require a warning starting 12 months after the listing. As a result, warnings for significant exposures will be required as of March 27, 2016.

Uses for beta-myrcene

Beta-myrcene, also known as myrcene or 7-Methyl-3-methyleneocta-1,6-diene, is a substance widely found in nature, and is used as an intermediate in the production of aroma and flavor chemicals. It is used in foods and as a scenting agent in fragrances, cosmetics, soaps and other cleaning products.

  • Food products – occurs naturally and is also used as a flavoring additive in food and beverage. This includes:
    • Fruits and vegetables, including mangoes, pomegranates, carrots and citruses, in juice and oil form.
    • Over 200 varieties of plants, including basil, hops, lemongrass, rosemary, tobacco and thyme;
    • Tea, such as lemongrass tea;
    • Beer, depending on the hops and other spices used, may contain some beta-myrcene;
    • Fruit, root beer and other flavorings for beverages, ice cream, candy and baked goods.
  • Fragrances – used as a “feedstock,” or a base component for, other fragrance ingredients used in perfumes, aromatherapy, and fresheners.
    • Several essential oils, including hop oil, verbena oil, lemongrass oil, and pimento oil among others, contain beta-myrcene.
  • Cosmetics, soaps, and cleaning products – used as a scenting agent in care products.

Future concerns

If they have not done so already, retailers should consider reaching out to vendors of these types of products to get information on whether they contain beta-myrcene, require warnings, or should be removed from sale in California. Suppliers and manufacturers of products containing beta-myrcene should consider contacting their retail customers to see whether customers anticipate still having these products in their California inventories as of that date.

We will continue tracking whether Prop 65 notices go out for these types of products, particularly given beta-myrcene’s natural occurrence in many fruits and plants. Other similar chemicals, like pulegone, do not appear to have given rise to much activity in the plaintiff’s bar.