Benzene, a known carcinogen, has been discovered in Mucinex (guaifenesin) generics in CVS, Walgreens, Target and other chain stores, Bloomberg reported Aug. 12.
Carbomers — which are thickening agents — used for the extended-release versions of the cold medicine might contain benzene, according to a Bloomberg analysis of government data. The chemical appears in multiple products — including dyes, detergents and some plastics — and prolonged exposure can cause leukemia and lymphoma.
The FDA has warned drugmakers about the risk of benzene contamination, and multiple recalls followed. By 2026, the United States Pharmacopeia plans to omit carbomers that are manufactured with benzene, Bloomberg reported.
Other than guaifenesin, the news outlet found about a dozen medications that contain carbomers made using benzene.
CVS said it is working with its supplier to replace the ingredient, Walgreens said it is working with suppliers to follow FDA regulations, and Walmart, Target and Rite Aid did not respond to Bloomberg's requests for comment.