California Residents Proposition 65 Warning FAQ

What is this warning?

You may see this warning label on some products that means the following: this product contains a chemical known to the State of California to cause cancer or reproductive harm. 

This warning can also appear at the point of purchas eor checkout for an online retailer or catalog item. 

California has two different types of warnings – warnings for cancer, and warnings for reproductive health effects. Some products may have one of the warning labels, and some may have both. Proposition 65 means these warnings are required by California labeling laws to notify buyers in California of exposure to Proposition 65-listed chemicals. Using these warning labels does not mean these items are banned by Proposition 65 in California: it only requires warnings.

What’s the difference between cancer and reproductive toxicity?

A chemical listed under Prop 65 as a carcinogen has been shown (often in laboratory animal studies) to cause cancer. A chemical listed under Prop 65 as a reproductive toxin has been shown (again, often in laboratory animal studies) to cause male or female reproductive toxicity or developmental toxicity. These tests are often performed with very high doses of chemicals. 

Does this law apply everywhere?

The "Prop 65" warnings are only required to be shown and placed under California law. California and Prop 65 standards are far more stringent than federal standards, and are among the harshest standards found.

What kinds of substances require warnings?

Over 800 chemicals have been listed under California Prop 65. They include pesticides, heavy metals, and Vitamin A at certain levels.

Certain listed chemicals, such as lead, are widely distributed through the environment in air, soil, water, and rocks. As a result, these types of chemicals are often found in commonly eaten foods and throughout the food supply even though these chemicals are not intentionally added to foods or nutritional supplements.

Should I be concerned?

You should always take head and be aware of warning labels. However, a warning label under Prop 65 does not necessarily mean the product will actually cause cancer or reproductive harm. The listing of a chemical under Prop 65 could be the result of tests on laboratory animals. Prop 65 standards for warnings are often very stringent. For example, for reproductive toxicants, the level for warnings is 1000 times lower than the lowest level at which animal studies reported no reproductive health effect. A Prop 65 warning does not automatically mean that the product is unsafe, merely that it contains those elements.

How are these warnings determined?

California has a formal process for adding chemicals to the Prop 65 list. Prop 65 allows chemicals to be listed in various ways, including through reports that are based on animal studies. In many instances, these animal studies involve extremely high dosages of chemicals to test at more stringent levels.

What kinds of substances are we talking about?

Many dietary supplements and nootropics contain substances that require a warning in California. One vitamin that requires a warning above a certain level is Vitamin A. Incidental contaminants such as lead and mercury also require warnings above a certain level even if they are not added intentionally to a product.

How do the California warnings compare to federal limits?

It's important to note that California product label warning requirements are often different from federal safety requirements. Due to this, there can be a mismatch between warnings on products sold in California and what is required throughout the rest of the United States. This can explain why sometimes you may see a California Prop 65 warning on a product sold in California but no warning on the same product sold elsewhere. The products are the same, but Prop 65 warnings are required for sales to California consumers.

Additionally, there are various substances that require a California Prop 65 warning at levels that are far more stringent than federal action limits. One example is lead. The Prop 65 standard for warnings for lead is 0.5 micrograms per day, which is far more stringent than federal and international standards for lead.

Why don’t all similar products carry the warning?

There are a lot of reasons. If a company has been involved in a Prop 65 lawsuit, and if that company reaches a settlement, that settlement may require Prop 65 warnings for products. Other companies that are not involved in the settlement, although they may nonetheless sell similar products, may not provide a warning on their product. Due to inconsistent Prop 65 enforcement, this sometimes explains why you will see certain products in the market with warnings, and virtually identical products without warnings. Other companies may elect not to provide warnings because, in their assessment, they conclude that they are not required to do so under Prop 65 standards. A lack of warnings for a product does not necessarily mean that the products is free of the same substances at similar levels, only that it has not yet been subjected to Prop 65 enforcement.

I’m confused, now what?

Prop 65 warnings are seen all over California no matter where you go -- in restaurants, grocery stores, hotels, schools, hospitals, and on a wide variety of consumer products. In addition, some internet and mail order retailers have chosen to provide Prop 65 warnings on their websites or in catalogs for all their products and for all consumers.

If you want more information, the one thing to do is to ask the manufacturer to explain the warning. But please remember that just because another brand does not have the warning, this does not automatically mean that the other brand is free of the substance or has lower levels.