Lawsuit Accuses Hair Dye Makers of Hiding Increased Bladder Cancer Risk

LOS ANGELES — Several hair dye manufacturers, including L’Oreal, Redken and John Paul Mitchell, were hit with a lawsuit filed in California state court by a hair stylist who alleges that harmful chemicals in their products caused him to develop bladder cancer.

In the complaint, filed Jan. 23 in the Los Angeles County Superior Court, Hector Corvera says the companies have known for years that routine exposure to their products could cause a 30 percent increased risk of bladder cancer, yet failed to include a warning on their labels.

“Hundreds of chemicals are used to make hair dyes, many are …