Talcum powder

Talc is a clay mineral composed of hydrated magnesium silicate with the chemical formula H2Mg3(SiO3)4 or Mg3Si4O10(OH)2. In loose form, it, along with corn starch, is one of the most widely used substances known as baby powder (in the case of talc, often called simply talcum powder). It occurs as foliated to fibrous masses, and in an exceptionally rare crystal form. It has a perfect basal cleavage, and the folia are non-elastic, although slightly flexible. It is the softest known mineral and listed as 1 on the Mohs hardness scale. As such, it can be easily scratched by a fingernail. It has a specific gravity of 2.5–2.8, a clear or dusty luster, and is translucent to opaque. Talc is not soluble in water, but is slightly soluble in dilute mineral acids. Its color ranges from white to grey or green and it has a distinctly greasy feel. Its streak is white.


Talc is used in many industries—including paper making, plastic, paint and coatings, rubber, food, electric cable, pharmaceuticals, cosmetics, and ceramics. A coarse grayish-green high-talc rock is soapstone or steatite, used for stoves, sinks, electrical switchboards, crayons, soap, etc. It is often used for surfaces of lab counter tops and electrical switchboards because of its resistance to heat, electricity and acids. Talc finds use as a cosmetic (talcum powder), as a lubricant, and as a filler in paper manufacture. Talc, with heavy refinement, has been used in baby powder, an astringent powder used to prevent rashes on the area covered by a diaper. The American Academy of Pediatrics recommends that parents not use baby powder because it poses a risk of respiratory problems—including breathing trouble and serious lung damage if the baby inhales it. The particles are so small that it is difficult to keep them out of the air while applying the powder. Zinc oxide-based ointments are a much safer alternative.

Sterile talc powder (NDC 63256-200-05) is a sclerosing agent used in the procedure of pleurodesis. This can be helpful as a cancer treatment to prevent pleural effusions (an abnormal collection of fluid in the space between the lungs and the chest wall). It is inserted into the space via a chest tube, causing it to close up, so fluid cannot collect there. The finished product has been sterilized by gamma irradiation.

Talc powder is a household item, sold globally for use in personal hygiene and cosmetics. Suspicions have been raised that its use contributes to certain types of disease, mainly cancers of the ovaries and lungs. It is classified in the same 2B category in the IARC listing as mobile phones and coffee. Reviews by Cancer Research UK and the American Cancer Society conclude that some studies have found a link, but other studies have not.

The studies discuss pulmonary issues, lung cancer, and ovarian cancer. One of these, published in 1993, was a US National Toxicology Program report, which found that cosmetic grade talc containing no asbestos-like fibres was correlated with tumor formation in rats forced to inhale talc for 6 hours a day, five days a week over at least 113 weeks. A 1971 paper found particles of talc embedded in 75% of the ovarian tumors studied. Research published in 1995 and 2000 concluded that it was plausible that talc could cause ovarian cancer, but there was no conclusive evidence.

In Hogans et al. v. Johnson & Johnson et al., No. 1422-CC09012 (22d Cir. Ct. Mo. February 23, 2016), a St. Louis jury linked ovarian cancer to the use of talcum powder for the first time in the United States and awarded actual and punitive damages ($10 mil / $62 mil respectively) to the family of an Alabama woman who died from ovarian cancer. There are at least 1,200 other talcum powder-related lawsuits pending, with about 1,000 of them in St. Louis.