Article

Acetonitrile: Properties, exposure, metabolism and toxicity

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Abstract

Acetonitrile is a colorless volatile liquid with a sweet burnt taste and an odor similar to ether. This substance has widely been used as an organic solvent in extractive processes, and it is commonly applied to the development and manufacturing of cosmetics, pharmaceutical and agricultural products. Numerous advantages of using acetonitrile in industrial processes have been reported, especially because this substance can be used as a catalyst in chemical reactions; it has also been applied as a key reagent in the synthesis of amines, amides, ketones, aldehydes, and other compounds. Despite its benefits, acetonitrile is a toxic substance that has adverse health effects and can lead to death. Human exposure generally occurs by inhalation acetonitrile vapors or by the absorption of the liquid or vapor through the skin and eyes. Acetonitrile poisoning can also occur by drinking contaminated water or by ingesting contaminated foods. The mechanisms of acetonitrile metabolism are in part mediated by reaction with the cytochrome oxidase in mitochondria. Acetonitrile blocks the reduction of oxygen needed for cellular respiration and thus leads to cytotoxic anoxia. The potential for acetonitrile toxicity depends on the amount, route (inhalation, contact, and ingestion), time and frequency of exposure(s); acute symptoms are usually abdominal pain, convulsions, labored breathing, weakness, unconsciousness and redness in the skin and eyes. With prolonged exposure, the liver, lungs, kidneys, and central nervous system may be affected. Because acetonitrile has not been shown cause cancer in rodents and does not cause gene mutation, its carcinogenic potential in humans is expected to be low. However, this information is uncertain because in male rats, a positive trend for liver tumor formation was confirmed. Furthermore, an increase of the incidence of basophiles was observed, which may represent a preneoplastic effect. It is important to mention that acetonitrile is readily absorbed by the lungs and the gastrointestinal tract and is thus quickly distributed throughout the body. Consequently, if exposure occurs, this substance must be rapidly removed from the body, and the procedures for detoxification should be started immediately because fast support is decisive for the treatment success. In general, the best way to prevent acetonitrile toxicity is to avoid acetonitrile exposure. This requires the use of personal protective equipment and hygiene as well as caution in handling, transport and storage. With these methods, the use of acetonitrile without risk to human health is possible. (Imprint: Nova).

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Article
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