Evaluation of toxic metal (Hg, Cd, Pb), polychlorinated biphenyl (PCBs), and pesticide (DDTs) levels in aromatic herbs collected in selected areas of Southern Italy.

This study provides, for the first time, data regarding levels of toxic metals (Hg, Cd, and Pb) and organochlorine compounds (PCBs and DDTs) in various aromatic herbs as rosemary (Rosmarinus officinalis), sage (Salvia officinalis), laurel (Laurus nobilis), oregano (Origanum vulgare), and spearmint (Mentha viridis) collected in some towns of the Southern Italy with different anthropogenic and population pressure. Metal and organochlorine compound concentrations were determined using atomic absorption spectrophotometer and gas-chromatography mass spectrometer (GC/MS), respectively. Pb emerged as the most abundant element, followed by Cd and Hg, while between organochlorine compounds, PCB concentrations were higher than those of DDTs. The pollutant concentrations were found to vary depending on the different herbs. The highest Pb levels were observed in rosemary (1.66 μg g-1 dry weight) and sage (1.41 μg g-1 dry weight), this latter showing also the highest Cd concentrations (0.75 μg g-1 dry weight). For PCBs, the major concentrations were found in rosemary (2.75 ng g-1 dry weight) and oregano (2.39 ng g-1 dry weight). The principal component analysis applied in order to evaluate possible similarities and/or differences in the contamination levels among sampling sites indicated differences area-specific contamination.