Experimental human exposure to N,N-dimethylbenzylamine: generation of a controlled atmosphere and biological monitoring.
The aim of the present study was to develop a method for generation of dimethylbenzylamine (DMBA) atmospheres in an exposure chamber and to investigate the possibility of using urinary DMBA metabolites for biological monitoring of exposure to DMBA. A DMBA atmosphere was generated by use of the gas-permeation principle. Six health male volunteers were exposed for 8 h to DMBA at air levels of 20, 45, and 80 microns/m3. Air levels of DMBA were analyzed by gas chromatography (GC). The total urinary amount of DMBA (U-SumDMBA; DMBA and metabolites that can be reduced to DMBA, e.g., DMBAO) was analyzed using GC-mass spectrometry (MS). The exposure chamber maintained very low (0-130 micrograms/m3) and steady concentrations for several weeks. DMBA uptake by inhalation was 76%. The amine was quickly distributed and biotransformed to nearly 100%. DMBA was eliminated in the urine with a half-time of 4.3 h. More than 50% was eliminated within 2 h of exposure. However, at all exposure levels the subjects continued to excrete DMBA the next morning. There was a significant correlation between the exposure to DMBA and the U-SumDMBA. Thus, U-SumDMBA may become an important biomarker for monitoring of industrial exposure to DMBA.
Ståhlbom
B
B
Department of Occupational and Environmental Medicine, University Hospital, Linköping, Sweden. Bengt.Stahlbom@fhvc.lio.se
Akesson
B
B
Jönsson
B
B
D000328:Adult; D000395:Air Pollutants, Occupational / Q000032:analysis / Q000493:pharmacokinetics*; D001273:Atmosphere Exposure Chambers; D001596:Benzylamines / Q000032:analysis / Q000493:pharmacokinetics*; D015415:Biomarkers; D004780:Environment, Controlled; D004781:Environmental Exposure / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods; D006801:Humans; D007509:Irritants / Q000032:analysis / Q000493:pharmacokinetics*; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male
D000395:Air Pollutants, Occupational; D001596:Benzylamines; D015415:Biomarkers; D007509:Irritants; C045966:N-benzyl-N,N-dimethylamine