Polycyclic aromatic hydrocarbons (PAH) comprise a family of more than 100 compounds, some of which are known or suspected to be mutagenic and/or carcinogenic to mammals. They are lipophilic organic contaminants composed by two or more fused aromatic rings. Although virgin olive oil (VOO) should be naturally free of PAH, contamination can occur either directly during the processing in the mill or indirectly due to olive skin contamination by environmental sources. In this last situation, PAH present in dust and particles from smoke and air pollution can contaminate olives via atmospheric fallout and this superficial contamination can be transferred to the final product. Aiming to identify and evaluate the sources of PAH contamination during the processing of VOO, the influence of factors such as the environmental pollution during olive growth, contamination during olive harvesting, contamination during extraction process and environmental pollution at the olive mill site has been studied. Nine PAH have been identified and, comparing the total PAH concentration in olive oils with olive fruit surface extracted with hexane, identical values for both cases were found. This finding suggests that the contamination of olive oil is mainly from the olive skin.
