According to an independent study sponsored by the nonprofit Center for Environmental Health, 98 shampoo products contained the carcinogenic chemical cocamide DEA, a form of coconut oil used as a thickener.

Last year, California's Office of Environmental Health Hazard Assessment listed cocamide DEA as a carcinogenic chemical likely to cause cancer.  Although the state has not declared a specific limit for this chemical in products, the CEH claims the levels of cocamide DEA were much higher than normal limits.

The CEH filed four lawsuits against major companies selling the products, and sent legal notices to more than 100 other companies. The San Francisco Chronicle reports these lawsuits are targeting any company whose use of the banned chemical resulted in more than 1 in 100,000 chance of its consumers developing cancer.

But the companies in question won't be facing a federal offense. The Food and Drug Administration has not banned cocamide DEA, and a 1998 test conducted by the organization did not establish a link between the chemical and an increased cancer risk. (Via Triple Pundit)