Biomonitoring of PAHs by using Quercus ilex leaves: Source diagnostic and toxicity assessment

► Spatial distribution of Quercus ilex leaf PAHs as indicative of the contamination degree. ► Assignment of PAH emission sources and assessment of carcinogenic potency. ► Spatial variability of leaf PAH content indicates the feasibility of Q. ilex as biomonitor of PAH contamination. ► The research findings highlight the source-diagnostic potential of Q. ilex leaves. ► In natural areas the toxicity, high as in urban areas, is driven by DB[a,h]A, due to biomass combustion.