Polycyclic aromatic hydrocarbons and polychlorinated biphenyls in sewage sludge from wastewater treatment plants of Kunming City

In this study, the concentrations, distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) and 28 polychlorinated biphenyls (PCBs) insewage sludge samples from wastewater treatment plants of Kunming citywere investigated. The total PAHs concentration (Sigma PAHs) varied from 1941 to3635ng/g, and the totalPCBs concentration (Sigma PCBs) ranged from 7.55 to 21.66 ng/g. The results of sources identification suggested that PAHs in sewage sludge were mostlyproduced from biomass and petroleum combustion. PCBs compositionand congener ratios indicated that the less chlorinated were the dominant source.