The San Francisco Chronicle reports ( http://bit.ly/1a0lHI6) the suit was filed Tuesday in Alameda County Superior Court by the Center for Environmental Health.
It accuses Walgreens, Lake Consumer Products, Vogue International and Ultimark Products of selling products that allegedly had cocamide DEA, which is used to make foam and bubbles.
Cocamide DEA was named last year as a carcinogen under Proposition 65, which requires warnings for consumer products with harmful amounts of certain toxic compounds.
The four companies sued Tuesday did not immediately respond to requests for comment.
The group says it plans to sue 100 more companies.
Information from: San Francisco Chronicle, http://www.sfgate.com