Johnson & Johnson is discontinuing North American sales of its talc-based baby powder

Johnson & Johnson is discontinuing North American sales of its talc-based baby powder, a product that once defined the company’s wholesome image and that it has defended for decades even as it faced thousands of lawsuits filed by patients who say it caused cancer.

The decision to wind down sales of the product is a huge concession for Johnson & Johnson, which has for more than a century promoted the powder as pure and gentle enough for babies.

The company said on Tuesday that it would allow existing bottles to be sold by retailers until they ran out. Baby powder made with cornstarch will remain available, and the company will continue to sell talc-based baby powder in other parts of the world.

Johnson & Johnson says that faulty testing, shoddy science and ill-equipped researchers are to blame for findings that it was contaminated with asbestos. But in recent years, thousands of people — mostly women with ovarian cancer — have said that the company did not warn them of risks that the company was discussing internally.