No general statement can be made as to the toxicity of ketones. Some are highly volatile and hence may have narcotic or anesthetic effects. Skin absorption, as well as inhalation, may be an important route of entry into the body. None of the ketones has been shown to have a high degree of chronic toxicity. Some are dangerous fire hazards. They react violently with aldehydes, HNO₃, HNO₃ + H₂O₂, HClO₄. A variety of peroxides can be formed from the reactions of ketones and hydrogen peroxide. Many of these peroxides are explosives sensitive to heat and shock. Common air contaminants. See also ACETONE, DIETHYL KETONE, and METHYL ETHYL KETONE.