Benzyl Alcohol

Abstract

Benzyl alcohol (CASRN: 100-51-6) is a clear, colorless liquid at room temperature that has gained broad use in commerce due to a wide range of advantageous properties including comparatively moderate toxicity, high polarity, solubility in water and other solvents, low vapor pressure, and faint pleasant aromatic scent. While its major commercial uses are in fragrances and in industrial processes as solvent and textile dye assistant, benzyl alcohol enjoys many other uses. It is an ingredient commonly found in consumer and healthcare products, and arises as a natural product in plants, fruits, tea, and wines. The principal routes of occupational exposure to benzyl alcohol are via inhalation and dermal contact where benzyl alcohol is produced or used. The general population may be exposed to this compound via dermal contact with consumer products, and to a lesser extent via inhalation of ambient air, ingestion of food, and drinking water. Its toxicity became notable when it was associated with the deaths of preterm infants. Chronic cancer studies have proven negative, as have the majority of genotoxicity studies. In humans, exposure to benzyl alcohol can produce irritation, allergic contact dermatitis, and central nervous system depression leading to convulsion, paralysis, and respiratory failure. Low concentrations of benzyl alcohol are used as a bacteriostatic agent in intravenous preparations. In healthy individuals, it is rapidly oxidized to benzoic acid in the liver, and then it is excreted as hippuric acid (glycine conjugate). Only one state (Florida, USA) has set minimum contamination level goal as 2100 μg l−1 in drinking water. Orally administered LD50 doses for this compound range from 1360 to 1580 mg per kg body weight and 1230–3120 mg per kg bodyweight for mice and rats respectively. The main treatment for benzyl alcohol toxicity is discontinuation of the exposure and supportive care. Hemodialysis may enhance the elimination of benzyl alcohol and its metabolites and may also be useful to help correct severe metabolic acidosis.