California Warning Labels Have Become a Joke. But They Work

Products containing more than 900 chemicals known to cause cancer, reproductive harm, or birth defects have to carry a big warning label under California's Proposition 65, passed by voters in 1986. The warnings appearing on baked goods, faux leather jackets, and even at Disneyland have become something of a joke, per the Washington Post. But combined with the threat of lawsuits and reputational harms, they've been "a great motivator for change," prompting many companies to stop using toxic chemicals entirely, Dr. Megan Schwarzman of the University of California, Berkeley, tells the New York Times.

In in-depth interviews with 32 business leaders across a dozen sectors, 81% said Prop 65 informed them which chemicals to avoid, 78% said they'd reformulated products so warning labels weren't required, and 63% said they'd even reformulated products sold outside California, per a study published Wednesday in Environmental Science & Technology. "What's interesting is that companies consistently told us they would rather eliminate a Prop 65 chemical altogether than post a warning," Schwarzman, a study co-author, says in a release. "By doing that, they avoid the threat of litigation, but they also reduce the risk to consumers and workers using the products."

"This shows that state laws can be really effective," even beyond the state's borders, lead study author Jennifer Ohayon, a research scientist at the Silent Spring Institute, tells the Post. The research follows a 2024 study that found levels of certain chemicals decreased in people's bodies in California and across the country after the chemicals were listed under the law. However, the study found levels of certain substitute chemicals increased, per the Times. (More California stories.)