Why talc, used in cosmetics and body powders, could actually be dangerous for your health ?

Talc, a natural mineral mined in many parts of the world, is "probably carcinogenic” for humans according to a study by experts from the International Agency for Research on Cancer published Friday July 5.

Talc is classified as a probable carcinogen by the cancer agency of the World Health Organization (WHO), which has also classified acrylonitrile, a compound used in the production of polymers, as a carcinogen. Experts from the International Agency for Research on Cancer (IARC/IARC), meeting in Lyon, published their results on Friday in the journal The Lancet Oncology.< /p>

They classified talc, a natural mineral mined in many parts of the world, as "probably carcinogenic” for humans, particularly given a combination of limited evidence of cancer in humans (ovarian cancer) and sufficient evidence in laboratory animals.

According to them, exposure mainly occurs in occupational settings during the extraction, grinding or processing of talc, or during the manufacture of products containing it. In the general population, it occurs in particular through the use of cosmetics and body powders containing talc.

Bias in the study

Nevertheless, experts do not exclude certain biases in studies which have shown an increase in the incidence of cancer. Although the assessment focused on talc not containing asbestos, contamination of talc with asbestos could not be excluded in most studies on exposed humans, they say.

In June, the American pharmaceutical giant Johnson & Johnson (J & J) reached a final agreement with the courts of 42 states in the United States in a talc case accused of causing cancer. A summary of studies, published in January 2020 and covering 250,000 women in the United States, did not find a statistical link between the use of talc on the parts genitals and the risk of ovarian cancer.

In the 1970s, concern arose about the contamination of talc with asbestos, often close in nature to the ores used to make talc. Then studies pointed to a higher risk of ovarian cancer among users of talcum powder.

Sufficient "evidence of lung cancer"

The WHO agency has also classified as "carcinogenic" for humans acrylonitrile, a volatile organic compound mainly used in the production of polymers. This decision is based on "sufficient evidence of lung cancer" and "limited" of bladder cancer in men, according to IARC.

These polymers are used in fibers for clothing, carpets, plastics for consumer products or automobile parts. Acrylonitrile is also present in cigarette smoke. Air pollution is another source of exposure.