Guide to California Proposition 65

June 15, 2022

Chemscape's Guide to the California Proposition 65

What is California Proposition 65?

California Proposition 65, also known as the Safe Drinking Water and Toxic Enforcement Act, is a “right to know” state law in California that requires businesses to provide warnings to Californians about significant exposures to chemicals that cause cancer, birth defects, or other reproductive harm. These chemicals can be in the products that Californians purchase, in their homes or workplaces, or those that are released into the environment. By requiring that this information be provided, California Prop 65 enables Californians to make informed decisions about their exposures to these chemicals.  

Proposition 65 also prohibits California businesses from knowingly discharging significant amounts of listed chemicals into sources of drinking water.  

Proposition 65 requires California to publish a list of chemicals known to cause health hazards such as cancer, birth defects, or other reproductive harm. This list, which must be updated at least once a year, has grown to include approximately 900 chemicals since it was first published in 1987.  

What types of chemicals are on the Prop 65 List?  

The Prop 65 list contains a wide range of naturally occurring and synthetic chemicals that 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 by-products of chemical processes, such as motor vehicle exhaust.  

On the OEHHA site you can also filter the list of chemicals by type of toxicity. These filter types include cancer, developmental toxicity, female reproductive toxicity, and male reproductive toxicity. There are approximately 900 chemicals on this list. 

What are the penalties for violating California Proposition 65?  

The penalties for violating Proposition 65 by failing to provide warnings can be as high as $2,500 per violation, per day.  

What do businesses need to do to comply with Prop 65?  

1. Provide clear and reasonable warnings 

Businesses are required to provide a "clear and reasonable" warning before knowingly and intentionally exposing anyone to a listed chemical, unless the business can show that the anticipated exposure level will not pose a significant risk of cancer or is significantly below levels observed to cause birth defects or other reproductive harm. 

2. Utilize warning labels and notices

This warning can be given in several ways, such as by labeling a consumer product, posting signs at the workplace, distributing notices at a rental housing complex, or publishing notices in a newspaper. The requirement to provide warnings takes effect one year after a chemical is added to the list.  

3. Refrain from releasing a listed chemical into drinking water

Proposition 65 also prohibits companies that do business within California from knowingly discharging listed chemicals into sources of drinking water. Once a chemical is listed, businesses have 20 months to comply with the discharge prohibition.  

Are there exemptions to Prop 65? 

Proposition 65 contains the following exemptions: 

  • Small businesses with less than 9 employees  
  • Government agencies & public water utilities  
  • If the product contains chemicals that occur naturally in foods 
  • If product contains chemicals that produce no observable effect at 1,000 times the level in question 
  • If a business can demonstrate that the chemical released in a drinking water source will not be significant (i.e. is undetectable or does not exceed the “no significant risk” levels) 

This means that even out of state manufacturers must comply when selling products in California.  

How Chemscape can help your business become Prop 65 Compliant

If your business sells products in California, Chemscape can take your product's chemical ingredients and apply it to the designated Prop 65 List. We will then generate a report indicating which toxic chemicals must be disclosed online and on-label in California. Get in touch with us today to learn more about our Chemical Management solutions and how we can assist with Proposition 65 compliance. 


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