WHO agency says talc is ‘probably’ carcinogenic

The World Health Organization’s cancer agency on Friday classified talc as “probably carcinogenic” to humans, but an outside expert warned against misinterpreting the announcement as a “smoking gun.”

The decision was based on “limited evidence” that talc could cause ovarian cancer in humans, “sufficient evidence” that it was linked to cancer in rats and “strong mechanistic evidence” that it exhibits carcinogenic symptoms in human cells, according to the International Agency for Research from the WHO. about cancer (IARC) said.

Talc is a naturally occurring mineral mined in many parts of the world and often used to make talcum powder.

According to the IARC in Lyon, most people are exposed to talc in the form of baby powder or cosmetics.

But the greatest exposure to talc occurs when talc is mined, processed or used to make products, it added.

The agency said there were numerous studies that consistently showed an increase in ovarian cancer in women who use talc on their genitals.

But it could not rule out that the talc in some studies was contaminated with carcinogenic asbestos.

“A causal role for talc could not be fully established,” said the agency’s findings, published in The Lancet Oncology.

Kevin McConway, a statistician at Britain’s Open University who was not involved in the study, warned that for the IARC’s assessment, the “most obvious interpretation is actually misleading.”

The agency only aims to “answer the question of whether the substance has the potential to cause cancer, under certain conditions that IARC does not specify,” he said.

Because the studies were observational and thus could not prove causality, “there is no evidence that talc use causes an increased risk of cancer,” he added.

The announcement comes just weeks after US pharmaceutical and cosmetics giant Johnson & Johnson agreed to pay $700 million to settle allegations that it misled customers about the safety of its talc-based powder products.

Johnson & Johnson admitted no wrongdoing in the settlement, even though it withdrew the product from the North American market in 2020.

A summary of studies published in 2020 among 250,000 women in the United States found no statistical association between the use of talc on the genitals and the risk of ovarian cancer.

Also on Friday, the IARC classified acrylonitrile, a chemical compound used to make polymers, as “carcinogenic to humans,” the highest alert level.

It cited “sufficient evidence” that acrylonitrile is linked to lung cancer.

The polymers made with acrylonitrile are used in everything from fibers in clothing to carpets, plastics and other consumer products.

© 2024 AFP