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 as a group 3 agent in the IARC listing. 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 no conclusive evidence was shown. https://en.wikipedia.org/wiki/Talc Pulmonary talcosis, less specifically referred to as talcosis, is a pulmonary disorder caused by talc. It has been related to silicosis resulting from inhalation of talc and silicates. It is also tied to heroin use where talc might be used as an adulterant to increase weight and street value. It is one of several noted associations and possible risks of street heroin use. Talcosis can also arise from the injection of drugs intended for oral administration, as talc is present in many tablets and capsules that are used intravenously, such as benzodiazepines, dextroamphetamine, and prescription opioids. https://en.wikipedia.org/wiki/Pulmonary_talcosis Is Talc an additive in cigarettes and does talc have any cause in Alzheimer plaques in the brain?