Gene Expression Network Analyses in Response to Air Pollution Exposures in the Trucking Industry

To investigate the cellular responses induced by air pollution exposures, we performed genome-wide gene expression microarray analysis using whole blood RNA sampled at three time-points across the work weeks of 63 non-smoking employees in the trucking industry. Our objective was to identify the genes and gene networks differentially activated in response to micro-environmental measures of occupational exposure to three pollutants: PM2.5 (particulate matter ≤ 2.5 microns in diameter) and elemental carbon (EC) and organic carbon (OC). Subjects were recruited from 10 trucking terminals in the northeastern US. The participants included workers whose job duties were characterized by different patterns of exposure: pick-up and delivery (P&D) drivers, dock workers, and office workers. Whole blood samples were collected using PaxGene RNA tubes, three times from each subject: (1) before the first shift of the workweek (first day, AM draw); (2) at the end of the first shift (8-12 hours later) on the same day (first day, PM draw); and (3) at the end of the last work shift of the same workweek (last day, PM draw). Micro-environmental samples of PM2.5, and EC and OC in PM1.0 were collected over the full workweek (24 hours/day for 6-9 days) at each of the 10 terminals. The final data set included 165 samples from 63 subjects.