Arizona Attorney General Kristin Mayes (D) filed a lawsuit against L'Oreal SA and its U.S. subsidiary on Thursday, September 10, 2026. The state alleges the cosmetics company violated consumer protection laws by failing to warn customers that its hair relaxer products could cause ovarian and uterine cancers. Arizona is the first state to file such a lawsuit against the company.
The legal action follows the 2022 release of a National Institutes of Health (NIH) study regarding hair straightening products. The researchers found that women who used these products several times a year were more than twice as likely to develop uterine cancer. The products, marketed under brands such as Dark and Lovely and Optimum, are used predominantly by African American women to permanently straighten textured hair.
The lawsuit claims that L'Oreal and associated companies prioritized profit over safety while marketing to women and children for decades. Arizona is seeking civil penalties and damages, as well as a court order that would prohibit the sale of these products unless they include a cancer risk warning. A spokesperson for L’Oreal USA stated on Friday, September 11, 2026, that the company is confident in the safety of its products and argued the claims lack legal and scientific merit.
L'Oreal already faces more than 12,000 similar lawsuits filed by individual users and their families. These cases have been consolidated in a Chicago federal court as part of a multidistrict litigation proceeding, which is a legal mechanism used to manage large numbers of similar lawsuits across different jurisdictions. Other manufacturers, including Revlon, have also been named in these suits and have denied any connection between their products and cancer.
The legal proceedings could have knock-on effects for the broader cosmetics industry and future consumer protection litigation. The state’s lawsuit introduces a new layer of government-led legal pressure alongside existing private mass torts. L’Oreal’s spokesperson noted that the 2022 NIH study did not establish a causal link, a point that will likely be a central focus of the legal arguments. If the state succeeds, it could set a precedent for other state attorneys general to file similar consumer protection suits against beauty product manufacturers based on emerging health studies.
What happens next depends on the scheduling of the state court case and the ongoing federal multidistrict litigation. Court records indicate the federal trials in Chicago could begin as early as 2027. In the Arizona case, the state is pursuing both financial penalties and a permanent injunction against the current marketing and sale practices. L'Oreal has indicated it will contest the allegations, maintaining that its products undergo rigorous safety reviews.