MEK (methyl ethyl ketone) is widely and frequently used as an ingredient of mixed solvents together with n-hexane.
MEK is known to decrease urinary levels of 2,5-hexanedione dose-dependently in an acute or chronic coexposure with a constant level of n-hexane.
This change in urinary 2,5-hexanedione appears to contradict the potentiation effect of MEK on n-hexane-induced neurotoxicity because it is believed that the toxicity of n-hexane is activated through n-hexane metabolism.
We aimed to clarify how the urinary level of 2,5-hexanedione changes when MEK modifies the degree of n-hexane-induced neurotoxicity.
A total of 32 male Wistar rats were divided into 4 groups of 8 each and were then exposed to fresh air only, 2000 ppm n-hexane only, 2000 ppm n-hexane plus 200 ppm MEK, and 2000 ppm n-hexane plus 2000 ppm MEK, respectively.
Inhalation exposures were performed 12 h/day, 6 days/week, for 20 weeks.
Motor-nerve conduction velocity (MCV), distal latency (DL), and urinary 2,5-hexanedione were measured every 4 weeks.
The MCV decreased, the DL increased, and urinary levels of 2,5-hexanedione increased in the 2000-ppm n-hexane plus 2000 ppm MEK group in comparison with the 2000-ppm n-hexane only group following 4 weeks'exposure.
On the 1st day of exposure, however, coexposure to MEK decreased urinary levels of 2,5-hexanedione dose-dependently. (...)
Mots-clés Pascal : Solvant organique, Hexane, Association toxique, Cétone, Butan-2-one, Exposition professionnelle, Médecine travail, Rat, Rodentia, Mammalia, Vertebrata, Toxicité, Potentialisation, Animal, Inhalation, Urine, Liquide biologique, Système nerveux pathologie, Hexane-2,5-dione
Mots-clés Pascal anglais : Organic solvent, Hexane, Toxic association, Ketone, 2-Butanone, Occupational exposure, Occupational medicine, Rat, Rodentia, Mammalia, Vertebrata, Toxicity, Potentiation, Animal, Inhalation, Urine, Biological fluid, Nervous system diseases
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 98-0172883
Code Inist : 002B03L04. Création : 11/09/1998.