Evaluation of potential neurotoxic effects of occupational exposure to (L)-lactates

Organo psyche syndrome (OPS) or chronic toxic encephalopathy (CTE) is a neu rotoxic condition reported following long-term exposure to paints containin g organic solvent and to other solvents. Lactate esters are finding wider u se as solvents. Lactate esters have been well studied in standard toxicity tests, but specific neurotoxicity studies have not been conducted. No clini cal signs of chronic neurotoxicity have been observed in standard toxicity tests, Lactate esters are rapidly hydrolyzed in the body to lactic acid and the corresponding alcohol. Alcohols have been reported to have acute neuro toxic effects, usually following high levels of ingestion. The literature o n alcohols was reviewed to establish the no-observed-adverse-effect level ( NOAEL) for acute neurotoxicity and to look for any evidence of chronic neur otoxicity from the alcohols produced by hydrolysis of the lactate esters, T he NOAELs were compared with the potential amounts of alcohol produced by h ydrolysis of different lactate esters at 200 mg/m(3) (the NOAEL for most of the lactate esters). In all cases neither acute nor chronic neurotoxicity would be expected based on the amounts of alcohol produced by hydrolysis of the lactate esters at their NOAELs. L-Lactic acid is a normal metabolite i n the body and is not considered neurotoxic. Based on this information ther e is no evidence to suggest that L-lactate eaters can cause any chronic neu rotoxicity, OPS, or CTE. (C) 2001 Academic Press.