On-road measurements of fine particulate matter (PM2.5) on roadways of Los Angeles.
Oxidative potential of PM2.5 quantified using the dithiothreitol (DTT) assay.
A 10-year comparison of PM2.5 chemical composition to previous near-road measurements.
Increased levels of on-road DTT activity in comparison to previous dynamometer studies.
Results from this study highlights the importance of non-tailpipe emissions.