Profile Analysis of Polycyclic Aromatic Hydrocarbons and Heavy Metals in Size Fractionated Highway Dust and Runoff Samples

摘要

A runoff monitoring was conducted at a highway drainage system in Switzerland. The runoffrnsamples with higher SS concentration had higher heavy metals and PAH concentrations. Thernparticle-bound Zn, Cu, Pb, and PAH concentrations were 155-524μg/L, 29-69μg/L, 13-46μg/L,rnand 1.3-3.3μg/L, which were close to literature values. Particle size distribution analysis revealedrnthat the runoff samples with higher SS concentrations contained coarser size fractions. Coarserrnfractions (>106μm) occupied more than half under the maximum peak flow condition, while thernmajor particles were finer than 45μm at low flow rate.rnIt was outstanding that the contents of heavy metals (Zn, Cu, and Pb) were about ten times higherrnin the runoff samples than in the three size-fractionated dusts (<50, 50-125, 125-250μm fractions).rnThe heavy metal profile of the runoff sample was similar to those of the finer fractions of the dusts.rnThe PAH content was higher in the dusts than the runoff samples, although the contents were bothrnin the same range of 10- 50μg/g. The PAH profiles in the fine size fractions (<50, 50-125, andrn125-250μm) of the dusts looked similar except for higher percentage of B(a)An in the <50μmrnfraction. On the contrary, the fraction of 250-400μm had a different feature expressed by higherrnpercentages of Ipy and B(ghi)Pe. Difference of PAH profiles among the seven runoff compositernsamples was negligible in spite of their different particle size distributions. The similarity reflectedrnthe fact that runoff particles mainly consisted of fine particles and the fine size fractions of the dustrnhad similar PAH profile. However, the dusts and the runoff particles showed different PAHrnprofile.