Critical review of the toxicity of methyl n‐butyl ketone: Risk from occupational exposure

Abstract

Methyl n-butyl ketone (MBK) was considered rather harmless until an outbreak of peripheral neuropathy occurred in 1973 among workers exposed to MBK. MBK easily penetrates the skin; pulmonary retention is approximately 80-85% in man. Distribution is widespread with highest levels in blood and liver; MBK also reaches the fetal tissues. MBK metabolism probably depends on the route of exposure, and is very similar to that of n-hexane. The critical organ is the nervous system. These effects find expression as peripheral neuropathy, with potential for serious effects of the central nervous system. From the viewpoint of neurotoxicity, 2,5-hexanedione is the most important metabolite. The neurotoxicity is potentiated by several compounds, while MBK itself potentiates the toxicity of other chemicals. From animal experiments, a no-adverse-effect level (NAEL) could not be established. Peripheral neuropathy may develop in workers exposed to only a few ppm of MBK. The difference in the Occupational Exposure Limits for MBK and n-hexane, as established by several organizations, is questioned in view of the neurotoxic effects of these substances.

High-Performance Cataluminescence Sensor Based on Nanosized V2O5 for 2-Butanone Detection

“…It finds wide use in the manufacture of plastics, textiles, paints and other coatings [ 4 ]. However, short-term inhalation exposure to 2-butanone causes irritation to the eyes, nose, and throat of humans, and even central nervous system depression [ 5 ]. Slight neurological, liver, kidney, and respiratory effects have also been observed in chronic inhalation studies of 2-butanone in animals.…”

Effects of methyl ethyl ketone, acetone, or toluene coadministration on 2,5-hexanedione concentration in the sciatic nerve, serum, and urine of rats

“…This dierence in metabolism can be considered a factor in the inconsistency of the ®ndings cited above. It has been reported that percutaneous absorption represents as much as 50% of the total absorbed dose of hexane (Cardona et al 1993), and other researchers have noticed that the percutaneous route plays some role in the absorption of hexane or MBK in industry (Bos et al 1991;Cardona et al 1996;Sakai 1996). As compared with inhalation exposure, the exposure dose resulting from subcutaneous injection is relatively constant.…”