On December 20, 2014, California’s Proposition 65 warning requirements for consumer, occupational, and environmental exposures to diisononyl phthalate (“DINP”) will take effect.  In the category of consumer exposures, manufacturers, brand owners, distributors, and retailers of products containing DINP will run the risk of being sued under Proposition 65 unless a clear and reasonable warning is provided for exposure to a Proposition 65 carcinogen or unless the regulated party can demonstrate that exposure from the product is below a level that would create a significant risk of causing cancer (a “no significant risk level,” or “NSRL”).

December 2013 Listing of DINP as Carcinogen

California’s Proposition 65 requires publication of a list of chemicals “known to the state” to cause cancer or reproductive toxicity.  On December 20, 2013, California’s Office of Environmental Health Hazard Assessment (“OEHHA”) listed DINP as a carcinogen known to the state to cause cancer.  (See December 12, 2013 B&D alert for more information.)  OEHHA has not identified a NSRL (i.e., safe-harbor level) for exposure to DINP, so a regulated party risks liability unless it either conducts a NSRL study and exposure assessment that proves exposure from a given product is below a safe level, or it provides a Proposition 65 carcinogen warning as outlined in the Proposition 65 regulations.  The Proposition 65 regulations also contain warning provisions for occupational and environmental exposures to listed chemicals.   

DINP is a phthalate ester primarily used as a general purpose plasticizer.  It is commonly used to improve the flexibility, pliability, and elasticity of a variety of polyvinyl chloride (“PVC”) plastic products, such as vinyl and faux leather, wire and cable insulation, plastic tubing and hoses, among other items.  Many non-PVC products also contain DINP, including some rubbers, inks, pigments, paints, lacquers, coated fabrics, adhesives, and sealants. 

Proposition 65 Citizen Suits

Proposition 65 allows citizens acting as “private attorneys general” to bring suits to enforce the warning requirements.  But a citizen plaintiff must notify the prospective defendant and public prosecutors of its intent to sue 60 days before a suit may be filed.  On and after the December 20, 2014 warning effective date, we anticipate that many manufacturers, brand owners and retailers of consumer products sold in California will begin to receive 60-day notices for products that allegedly expose users to DINP.