Dermal absorption and urinary elimination of N-methyl-2-pyrrolidone

Abstract

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.

Characterization of the Polyurethanolytic Activity of Two Alicycliphilus sp. Strains Able To Degrade Polyurethane and N -Methylpyrrolidone

“…Proteus mirabilis culture SN was used as the enzyme source for positive controls. To determine the amount of NH 4 ϩ released in the reaction, a standard curve was performed by using NH 4 Cl and phenol and NaClO solutions as described above. Esterase activity was measured spectrophotometrically by a p-nitrophenyl acetate (p-NPA) hydrolysis method (13).…”

Dimethyl sulfoxide (DMSO) [MAK Value Documentation, 2011]

“…The experimental design of this study (for example, unusually long storage of the excised skin in a liquid medium and stretching of the skin during exposure) deviates considerably from the OECD (2004) recommendations for conducting skin penetration studies by means of diffusion cells. However, when the fluxes determined for toluene, N-methyl-2-pyrrolidone and N,N-dimethylformamide in the study of Ursin et al (1995) were compared with those given in the literature (Ahaghotu et al 2005;Bader et al 2005;Kezic et al 2001;Larese et al 1994) the level of agreement of the values was acceptable. Dermal application of an 80% DMSO gel in a dose of 1000 mg/kg body weight and day induced central nervous symptoms in humans, transient eosinophilia and in some cases severe local skin reactions caused by the release of histamine (Brobyn 1975).…”

Human volunteer study on the influence of exposure duration and dilution of dermally applied N-methyl-2-pyrrolidone (NMP) on the urinary elimination of NMP metabolites

“…The study was approved by the Ethics Committee of Hannover Medical School and the participants gave their informed consent prior to the study. A medical cellulose pad spiked with NMP or an aqueous dilution of the solvent was attached to the back of one hand of every participant and was protected against vapourisation by an aluminium foil as described by Bader et al (2005a). The average pad surface area was »10 cm 2 .…”

“…The half-life of 5-HNMP in urine of 3-4 h contrasts the results of Akrill et al (2002) (»11 h), assumed to be a result of the higher dilution and delayed intracorporal distribution of NMP in the latter study. Focusing on the dermal uptake and elimination of metabolically unchanged NMP, Bader et al (2005a) exposed six volunteers to 17.5 cm 2 cellulose pads spiked with 1,045 mg NMP under occlusive conditions for 2 h and followed the urinary elimination of the solvent for 72 h. An elimination maximum of 1 h post-exposure and a halflife of 3.2 h were reported (Åkesson et al 2004: 2.9-3.7 h). The average dermal absorption of NMP calculated from the pad weight diVerences before and after the exposure was 5.5 mg cm ¡2 h ¡1 (range: 4.0-8.3).…”