Dermal absorption and urinary elimination of N-methyl-2-pyrrolidone.
OBJECTIVE
The dermal absorption of the solvent N-methyl-2-pyrrolidone (NMP) and its elimination in urine was investigated in an experimental study.


METHODS
Seven volunteers were exposed to 1045 mg of liquid NMP under occlusive conditions for 2 h. Urine was collected before, during and up to 72 h after the exposure and analysed for NMP by GC/MS after liquid-liquid extraction. Additionally, the remaining NMP in the pads was determined to estimate the total dermal uptake.


RESULTS
The concentration of NMP in urine increased rapidly after beginning of the exposure up to 1 h after the exposure was completed. A peak concentration of 1,836+/-863 microg/l was observed, the half-life in urine was 3.2 h. About 0.5% of the absorbed dose was excreted metabolically unchanged. An average dermal absorption of 5.5 mg cm(-2) h(-1) was calculated.


CONCLUSIONS
The results of this study show that the percutaneous absorption of NMP may contribute significantly to the overall uptake of the solvent, e.g. in the workplace. Therefore, a biological monitoring of NMP exposed workers is essential for occupational-medical surveillance.
Department of Occupational Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, D-30625, Hannover, Germany. bader.michael@mh-hannover.de
Michael
M
Bader
Stephen A
SA
Keener
Renate
R
Wrbitzky
D000287:Administration, Topical; D000328:Adult; D004784:Environmental Monitoring; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D011760:Pyrrolidinones / Q000493:pharmacokinetics* / Q000633:toxicity; D012869:Skin Absorption / Q000502:physiology*; D012997:Solvents / Q000493:pharmacokinetics* / Q000633:toxicity*
D011760:Pyrrolidinones; D012997:Solvents; C038678:N-methylpyrrolidone