Contamination from polycyclic aromatic hydrocarbons (PAHs) in the soil\ud of a botanic garden localized next to a former manufacturing gas plant in\ud Palermo (Italy)

摘要

The Botanical Garden lies within the city of Palermo, a few meters away from one of the largest unused\udManufacturing Gas Plant in Sicily. The total concentrations of PAHs (23 compounds) in the soil of Botanical\udGarden ranged from 947 to 18,072 g/kg. The wide range of PAH concentrations (RSD = 84%) found in the\udsoil samples indicates heterogeneous levels of contamination in the area and this can be explained by\udconsidering the different tree distributions which prevents the homogeneous deposition of pollutants on\udthe soil. Soils collected in the Botanical Garden generally showed the highest PAH concentrations, being\udalmost 2–3 times higher than the concentration samples obtained in the urban reference sites and about\ud20 times higher than those in the rural stations. The total PAH concentrations, in the Botanical Garden soil,\udresulted higher than the maximum concentrations allowed by the Italian legislation for the green areas.\udPerylene, was found in all the stations. From a careful study of the isomeric ratios,wecan hypothesize that\udthe soils of the Botanical Garden are mainly affected by localized MGP particulate deposition, suggesting\udthat the partitioning between organic matter and PAHs is not the dominant process in the soils with\udhigher organic matter content.\ud©