World Health Organization classifies substance used by millions as carcinogenic

The International Agency for Research on Cancer, affiliated with the World Health Organization, has classified talc as a possible carcinogen, while acrylonitrile, a compound used in the production of polymers, has been included on the list of carcinogenic substances.

At a meeting in the French city of Lyon, experts from the agency published their findings in the journal "The Lancet Oncology" on Friday.

They classified talc, a natural mineral extracted in many parts of the world, as "possibly carcinogenic" to humans, especially in light of a limited set of evidence of cancer in humans (ovarian cancer), and sufficient evidence in laboratory animals.

According to the experts, exposure occurs mainly in occupational environments during the extraction, grinding or processing of talc, or during the manufacture of products containing it.

This occurs in millions of people in particular through the use of cosmetics and body care powders containing talc.

However, experts do not rule out some gaps in studies that have shown an increase in cancer rates.

They say that while the review focused on talc that does not contain asbestos, asbestos contamination of talc cannot be ruled out in most studies of humans exposed to the substance.

In June, the US drugmaker Johnson & Johnson reached a final settlement with the courts of 42 US states in a case over talc’s alleged cancer-causing properties.

A summary of studies published in January 2020, which included 250,000 women in the US, found no statistical link between genital talc use and ovarian cancer risk.

Concerns arose in the 1970s about asbestos contamination of talc, which is often close in nature to the raw materials used to make talc.

Studies then suggested that women who used talc were at increased risk of ovarian cancer.

The World Health Organization has also classified acrylonitrile, a volatile organic compound used mainly in the production of polymers, as a “probable carcinogen” for humans.

The decision is based on “sufficient evidence of lung cancer” and “limited evidence of bladder cancer in men,” according to the International Agency for Research on Cancer.

These polymers are used in the manufacture of clothing fibres, carpets and plastics for consumer products or car parts.