Important information regarding Prop. 65 for CA residents


Proposition 65, known as the Safe Drinking Water and Toxic Enforcement Act of 1986, aims to protect drinking water sources and California citizens from exposure to chemicals known to cause cancer, birth defects, or other reproductive harm. 

The law requires people be informed about exposure to such chemicals. The State of California maintains and updates a list of chemicals known to cause cancer or reproductive toxicity. This list is presented in the next section (see link on bottom of page) and includes nearly 1000 substances. Proposition 65 also prohibits California businesses from knowingly discharging significant amounts of listed chemicals into sources of drinking water.

What types of chemicals are on the Proposition 65 list?

The list contains a wide range of naturally occurring and synthetic chemicals that are known to cause cancer or birth defects or other reproductive harm. These chemicals include additives or ingredients in pesticides, common household products, food, drugs, dyes, or solvents. Listed chemicals may also be used in manufacturing and construction, or they may be byproducts of chemical processes, such as motor vehicle exhaust. Some ubiquitous products such as wood dust, carbon black, and aspirin are included on the list. 

All naturally occurring or manufactured products (including appliances) could contain some products in trace amounts which are on this list. California law requires businesses to warn customers of potential exposure of such substances, and a warning is required if even one chemical from the list may be present. 

The FAQ below is reproduced from the CA Proposition 65 website:

Q: Is a product safe if it carries a Proposition 65 warning?

A: The purpose of Proposition 65 is to notify consumers that they are being exposed to chemicals that are known to cause cancer and/or reproductive toxicity. Consumers can decide on their own if they want to purchase or use the product. A Proposition 65 warning does not necessarily mean a product is in violation of any product-safety standards or requirements. 

For chemicals that are listed as causing cancer, the "no significant risk level" is defined as the level of 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. In other words, a person exposed to the chemical at the "no significant risk level" for 70 years would not have more than a "one in 100,000" chance of developing cancer as a result of that exposure. 

For chemicals that are listed as causing birth defects or reproductive harm, the "no observable effect level" is determined by identifying the level of exposure that has been shown to not pose any harm to humans or laboratory animals. Proposition 65 then requires this "no observable effect level" to be divided by 1,000 in order to provide an ample margin of safety. Businesses subject to Proposition 65 are required to provide a warning if they cause exposures to chemicals listed as causing birth defects or reproductive harm that exceed 1/1000th of the "no observable effect level. 

For general information on the Proposition 65 list of chemicals, you may contact OEHHA's Proposition 65 program at (916) 445-6900, or visit their website at

NOTE: This information is a summary interpretation and was prepared as general reference material only. This summary cannot be considered authoritative as laws can be amended over time. For specific compliance requirements and updates, please refer to the actual California Regulations or your legal counsel.