“…They mainly originate from anthropogenic activities, such as incomplete combustion of organic materials (e.g., wood, coal oil, gas, tobacco and straw), as well as from automobile exhausts and industrial processes (Yunker et al, 2002a(Yunker et al, , 2002b. As a result, PAHs have been used to assess the magnitude of anthropogenic impacts on the environment (Jones et al, 1989;Page et al, 1999;Liu et al, 2012bLiu et al, , 2012cYang et al, 2012).…”