Herein a new approach, which utilizes acidified filter in sampling, solid-phase microextraction (SPME) in extracting and GC/FID in analysis, was developed and evaluated for monitoring airborne trimethylamine. The results indicate that the mean collection efficiency of the acidified filter is 105.1% and the breakthrough volume is 241, based on a sampling rate of 100 cc/min and concentration at two times the recommended exposure level. The extraction time is 5 min, a non-equilibrium condition, using PDMS fiber. The calibration range is 0.04-0.8 mg and the mean recovery is 100.4%. The analysis coefficient of variation (CVa) and the total coefficient of variation (CVT) is 2.11 and 3.4%, respectively. Samples are stable for at least 28 days under both ambient and freeze conditions. In short, this method is simple, feasible and with satisfactory accuracy and precision, and thus can be used as a reference method for monitoring occupational exposure to trimethylamine. (C) 2000 Elsevier Science B.V. All rights reserved.
