Human volunteer study on the inhalational and dermal absorption of N-methyl-2-pyrrolidone (NMP) from the vapour phase
- 264 Downloads
N-Methyl-2-pyrrolidone (NMP) is a versatile organic solvent frequently used for surface cleaning such as paint stripping or graffiti removal. Liquid NMP is rapidly absorbed through the skin but dermal vapour phase absorption might also play an important role for the uptake of the solvent. This particular aspect was investigated in an experimental study with 16 volunteers exposed to 80 mg/m3 NMP for 8 h under either whole-body, i.e. inhalational plus dermal, or dermal-only conditions. Additionally, the influence of moderate physical workload on the uptake of NMP was studied. The urinary concentrations of NMP and its metabolites 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI) were followed for 48 h and analysed by gas chromatography–mass spectrometry (GC–MS). Percutaneous uptake delayed the elimination peak times and the apparent biological half-lives of NMP and 5-HNMP. Under resting conditions, dermal-only exposure resulted in the elimination of 71 ± 8 mg NMP equivalents as compared to 169 ± 15 mg for whole-body exposure. Moderate workload yielded 79 ± 8 mg NMP (dermal-only) and 238 ± 18 mg (whole-body). Thus, dermal absorption from the vapour phase may contribute significantly to the total uptake of NMP, e.g. from workplace atmospheres. As the concentration of airborne NMP does not reflect the body dose, biomonitoring should be carried out for surveillance purposes.
KeywordsN-Methyl-2-pyrrolidone Dermal absorption Biomonitoring GC–MS
This study was financially supported by grants of the NMP Producers Group, c/o Bergeson & Campbell, Washington DC, USA.
- ACGIH (American Conference of Governmental Industrial Hygienists) (2007) Threshold limit values and biological exposure indices. Signature Publications, ISBN 978-1-882417-69-8Google Scholar
- Åkesson B (2001) N-methyl-2-pyrrolidone. Concise International Chemical Assessment Document 35, World Health Organization, Geneva, ISBN 9 241 53035 9Google Scholar
- Beaulieu HJ, Schmerber KR (1991) M-Pyrol™ (NMP) use in the microelectronics industry. Appl Occup Environ Hyg 6:874–880Google Scholar
- Brooke I, Cocker J, Delic JI, Payne M, Jones K, Gregg NC, Dyne D (1998) Dermal uptake of solvents from the vapour phase: an experimental study in humans. Ann Occup Hyg 8:531–540Google Scholar
- Carnerup MA (2004) Analysis, metabolism, effects and biological monitoring of N-methyl-2-pyrrolidone (NMP). Thesis, Faculty of Medicine, Lund University, SwedenGoogle Scholar
- Cocker J, Akrill P, Bagon D, Roff M, Warren N (2004) Biological monitoring of exposure to N-methyl-2-pyrrolidone during graffiti and paint removal. In: 6th International symposium on biological monitoring in occupational and environmental Health, HeidelbergGoogle Scholar
- DFG (Deutsche Forschungsgemeinschaft) (2006) N-Methyl-2-pyrrolidon. In: Greim H (ed) Gesundheitsschädliche Arbeitsstoffe. Toxikologisch-arbeitsmedizinische Begründungen von MAK-Werten. Suppl 41. Wiley, WeinheimGoogle Scholar
- DFG (Deutsche Forschungsgemeinschaft) (2007) List of MAK and BAT values. Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area. Report No. 43, Wiley, WeinheimGoogle Scholar
- HSE (Health and Safety Executive) (1997) N-Methyl-2-pyrrolidone. Risk assessment document. EH72/10, ISBN 0717615286, HSE Books, SudburyGoogle Scholar
- Jönsson BAG, Åkesson B (2003) Human experimental exposure to N-methyl-2-pyrrolidone (NMP): toxicokinetics of NMP, 5-hydroxy-N-methyl-2-pyrrolidone, N-methylsuccinimide and 2-hydroxy-N-methylsuccinimide (2-HMSI), and biological monitoring using 2-HMSI as a biomarker. Int Arch Occup Environ Health 76:267–274PubMedGoogle Scholar