Skip to main content

The Knowledge Center

California Proposition (CA Prop) 65

California Prop 65 Warnings & Compliance

California Proposition 65 (Prop 65) is the Safe Drinking Water and Toxic Enforcement Act of 1986 published as Section 25249.7 of California's Health and Safety Code. Proposition 65 is administered by the Cal/EPA Office of Environmental Health Hazard Assessment (OEHHA) and is enforced by California Department of Justice, Office of the Attorney General. Proposition 65 is intended to warn consumers of potential exposures to chemicals that are recognized by the State as carcinogens and reproductive toxins. Prop 65 applies to all consumer goods sold within the state and impacts all importers, domestic manufacturers, and retailers of these items. Compliance with the law is difficult due to the lack of clearly defined standards and guidelines for estimating potential exposures and to the lack of OEHHA exposure guidelines for many of the listed chemicals. Additional ambiguity regarding compliance is created because most of the legal activity is not initiated by the State but rather by private law firms and consumer advocacy groups acting in the public interest.  

Berkeley Analytical, as a California-based laboratory, is well informed regarding Proposition 65 issues and tracks legal activities filed with the State Attorney General that are impacting the industries we serve. Companies use our analytical services to assess potential Proposition 65 liabilities, manage their processes and supply chains for compliance with the regulation, and defend themselves against litigation.

Our phthalate and SVOC testing often is used to measure the content of specific Prop 65 phthalate esters and halogenated flame retardant chemicals in products. Such testing is particularly useful for quality control programs. Manufacturers potentially can limit liability through purchasing specifications and by routinely monitoring the content of listed chemicals in the components and materials they purchase.

The six phthalate esters contained in Proposition 65, particularly di-(2-ethylhexyl)phthalate (DEHP) and diisononyl phthalate (DINP), are generating considerable legal activity accounting for about 44% of the total Proposition 65 legal judgment and settlement payments by defendants in 2019.

BkA's VOC emission testing generates information that can be used to evaluate potential inhalation exposures to listed volatile organic compounds (VOCs). In addition to our regular testing services, we can create testing protocols for estimating the decay in the emissions of chemicals over long time periods that are of interest with respect to assessing exposures to VOCs listed as carcinogens. Our network of toxicology professionals can develop risk assessments needed to determine if Prop 65 labeling is required and to help manufacturers defend against Prop 65 lawsuits.

A number of commonly used VOCs, including formaldehyde, styrene and naphthalene, are on the Proposition 65 list. A recent addition, p-Chlorobenzotrifluoride (PCBTF), is a VOC used extensively as a solvent in paints, coatings and inks because the U.S. EPA ruled in 1994 that it is exempt for the purpose of outdoor VOC emissions regulations. PCBTF was added to the list as a carcinogen on June 28, 2019. As the result of this listing manufacturers were required to be in full compliance with the labeling requirements for PCBTF by the end of June 2020.

Prop 65 List of Chemical Substances

The law requires the State to publish a list of chemicals that are known to cause cancer or birth defects or other reproductive harm. This list is updated at least annually and has grown since first publication in 1987 to include over 1000 chemical substances. The list contains a wide range of synthetic and naturally occurring chemicals. These chemicals include ingredients and additives in products that are commonly used and contained in homes, schools and offices such as personal care products, household cleaners, furniture, and building and construction products. Chemicals are nominated for inclusion in the list by different mechanisms. There are two independent committees appointed by the Governor as the state's qualified experts. Either of these committees can recommend a chemical for inclusion based on current scientific literature. In this case, OEHHA compiles the evidence for the committee to review and publishes the document for public comment. OEHHA also considers several other governmental agencies as authoritative bodies and adopts their assessments of chemicals for cancer and developmental effects. The designated authoritative bodies are the U.S. EPA, the U.S. FDA, NIOSH, the National Toxicology Program, and IARC.

Prop 65 Clear and Reasonable Warnings

Proposition 65 is a product labeling law related to potential consumer exposures. It is NOT a product content law. Companies doing business in California are required to provide a "Clear and Reasonable Warning" before knowingly and intentionally exposing anyone to a listed chemical over defined levels. The warning can be delivered to consumers in various ways. For goods sold to consumers, the warning often consists of an on-product label.

For listed carcinogens, a "No Significant Risk Level" (NSRL) is defined as an exposure that would result in not more than one excess case of cancer in 100,000 individuals exposed to the chemical over a 70-year lifetime. For reproductive toxicants, a "no observable effect level" or NOEL that has been shown not to pose any harm to humans or laboratory animals is determined. A Maximum Allowed Dose Level (MADL) is established as 1/1000 of the NOEL. If exposures are likely to exceed an NSRL or MADL, then a product warning is required. OEHHA develops numerical "Safe Harbor Numbers" for exposures that provide risk-based guidance on labeling. To date, there are about 300 safe harbor levels. If there is no safe harbor level, a significant amount of chemical exposure often is interpreted broadly as any detectable amount. Alternately, businesses may choose to perform specific risk assessments by consulting with qualified toxicologists.

OEHHA enacted extensive revisions to Proposition 65 Section 6 on Clear and Reasonable Warnings that became effective in August 2018. The revisions to Section 6 are intended to further the “right-to-know” purposes of the law and to provide specific guidance on the content of safe harbor warnings for a variety of exposure situations, and on the corresponding methods for providing those warnings. The revisions also make clear distinctions between the responsibilities of manufacturers and their supply chains versus the responsibilities of retailers.

The text of the new warnings requires that at least one chemical name be listed. If multiple chemicals result in the requirement for a warning label, the manufacturer may list all of the chemicals but only is required to list one. The new labels state “This product can expose you to [name of one or more chemicals] a chemical [or chemicals] known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to"

Prop 65 Enforcement

Proposition 65 is not directly enforced by a regulatory agency. Instead, the California Attorney General's Office enforces the law as may any district or city attorney of cities with populations >750,000. Significantly, any individual acting in the public interest also may enforce the law by filing a lawsuit against a business for allegedly violating the law. This latter path is being pursued by consumer advocacy groups and law firms and is how most of the legal cases are initiated. In this circumstance, the public interest party first sends the business a 60-day notice of the violation before filing a lawsuit. Upon receiving a 60-day notice, many businesses choose to seek legal advice. Most of these public interest cases do not go to trial but rather are settled out of court by agreements. In 2019, the Proposition 65 settlements totaled approximately $30M.

Return to top

Inquiry Form

Please fill out the form to be contacted by a laboratory expert. Tell us as much as you can about your needs. We’ll promptly respond to your inquiry and answer your questions about all aspects of testing/analysis including pricing. If you prefer, call us at 1-510-236-2325, toll-free at 1-888-455-0999 or email