Development of Sampling and Analytical Methods for Toxicants in Diesel Exhaust Streams

摘要

This report presents the results of a development-validation program for sampling and analysis methods for unregulated diesel exhaust contaminants. Three compound classes were selected for study including polynuclear aromatic hydrocarbons (PAH), light oxygenates (carbonyls), and heavy oxygenates (odorants). Sampling and analysis methods were developed and validated in a laboratory and evaluated in a diesel exhaust or mine air matrix. A high-performance liquid chromatographic (HPLC) method was evaluated for analysis of aldehydes and ketones in diluted diesel exhaust and mine air. Sampling schemes to collect carbonyls in these two matrices were also developed. A sampling method to collect odorants in diesel exhaust was developed by limited modification of available sampling schemes. The odorant analysis method evaluation is based on a diesel odor analyses system that utilizes liquid chromatography. The analytical methods developed for analysis of PAH utilized either a reverse phase HPLC or a capillary column gas chromatography-mass spectrometry technique coupled with various sample preparation steps. The developed procedures were found to be suitable for exhaust emission analyses. Interferences are minimal in all methods except for the HPLC analysis of PAH where PAH derivatives may interfere. The results of validation experiments indicate good recovery of specific compounds based on standard studies for individual methods.