Differences in accumulation of polycyclic aromatic compounds (PACs) among eleven broadleaved and conifer tree species

PACs (polycylic aromatic compounds) are air pollutants formed in incomplete combustion, e.g., vehicle engines. Vegetation can potentially remove substantial amounts and act as bioindicators of these pollutants. Increased knowledge the pollutant removal efficiencies different tree species is essential for understanding potential benefits trees provide urban residents. We investigated leaf/needle content two PAC groups, polycyclic hydrocarbons (PAHs, 32 dibenzothiophenes (DBTs, 6 seven broadleaved four conifer an arboretum South-West Sweden. PAHs were grouped into low-molecular (L-PAHs, largely gaseous), medium-molecular (M-PAHs, both gaseous particle-bound) high-molecular mass (H-PAHs, PAHs. DBTs organosulphur compounds with benzene rings. In general, needles stronger accumulators than leaves trees. Comparing three-year-old one-year-old showed that evergreen conifers accumulated L-PAHs, M-PAHs, H-PAHs over several years. deciduous trees, L-PAHs declined from June to September, M-PAHs had no significant net change, but H-PAHs, there was a accumulation. Conifers similar or lower average annual accumulation except Larix, which highest uptake rate this toxicologically important PAH category. Our results suggest L-PAH depends on volume, while area more important. This explains why represented sink M-PAHs. DBT leaves/needles L-PAHs. An conclusion accumulate strong complex contrasts between groups. Another implication our data useful pollution since they all categories