Figure 2

The influence of speed and diesel type on the composition and B[a]P toxicity equivalents (B[a]Peq) of PM 2.5 in the exhausts. Exhausts were collected from trucks with gasoline or diesel engine under idle and high (70 km/h) speeds and the PM2.5 content and the total contents of ions and PAHs (∑24-27PAHs) in PM2.5 particulates were quantitated as described in the Methods.