IARC: Acrylonitrile Causes Cancer, Talc Is “Probably Carcinogenic”
The International Agency for Research on Cancer (IARC) has classified the chemical substance acrylonitrile as a Group 1 carcinogen and therefore carcinogenic to humans. IARC last evaluated acrylonitrile in 1998 and previously classified it as Group 2B, possibly carcinogenic to humans. According to the agency’s latest evaluation, acrylonitrile causes lung cancer, and “[p]ositive associations have been observed between acrylonitrile and cancer of the bladder.” IARC also notes sufficient evidence for cancer in experimental animals exposed to the substance.
The agency describes acrylonitrile, which is used in the manufacture of plastics, synthetic rubber, and acrylic fibers, as “a chemical with a high production volume.” Workers in production industries can be exposed to it via inhalation and dermal routes, while other exposures stem from first- and secondhand tobacco smoke, air pollution, contact with contaminated consumer products, and potentially 3D printers, IARC explains. The agency’s findings appear in a new volume of the IARC Monographs series that was published last month.
The recently published Volume 136 also outlines IARC’s evaluation of the carcinogenicity of talc, which the agency defines as “a mineral (natural) or synthetic product, a hydrated magnesium silicate, that exists in both lamellar and fibrous (including asbestiform) types.” IARC has classified talc as a Group 2A carcinogen, its designation for substances that are probably carcinogenic to humans, superseding two previous evaluations: talc not containing asbestos or asbestiform fibers and perineal use of talc-based body powder. Talc containing asbestos is not included in this new evaluation, and IARC stresses that talc containing asbestos “retains its classification in Group 1” as carcinogenic to humans.
Like acrylonitrile, talc also has a high production volume, with uses ranging from plastics, ceramics, and roofing materials to cosmetics, personal care products, and pharmaceuticals. Workers can be exposed to talc dust during mining and milling activities or during work in downstream industries. IARC notes that the general population is typically exposed to talc in consumer products.
The new volume of the IARC monographs series is freely available on the agency’s website. Additional details can be found in an IARC news article.