GC-MS analysis of polycyclic aromatic hydrocarbons in bottled olive oil marketed in Lebanon.

Abstract

Lebanon has witnessed elevated levels of pollution over the last few years due to increased waste incineration, emissions from vehicles and electricity generators, and mass demonstrations involving the burning of tires. The resultant generation of polycyclic aromatic hydrocarbons (PAHs) from the incomplete combustion of organic materials present in these sources may contaminate various foods including olive oil. Lebanon has a sizeable olive oil industry that is a main pillar of its agricultural sector. In this study, we investigated the occurrence of 16 semi-volatile lipophilic organic pollutants in 25 bottled olive oil brands, marketed in Lebanon, using a solid phase extraction (SPE) method followed by gas chromatography mass spectrometry (GC-MS). PAHs were detected in 60% of brands (41% of samples) where 12% of brands contained traces of probably carcinogenic (Class 2A) compounds and 56% of brands contained traces of possibly carcinogenic (Class 2B) compounds. One brand revealed levels of benzo[a]pyrene of 9.45μg/kg and 11.9μg/kg in batches collected over two production dates which are higher than the limit set by the European Commission for benzo[a]pyrene in food (2μg/kg). The same batches contained a total of 19.3μg/kg and 26.7μg/kg of the four PAHs: benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and chrysene which also exceeded the limit set by the EC for the combination of these four PAHs in olive oil (10μg/kg). This study is the first-of-its-kind in Lebanon and emphasizes the need to perform adequate cleanup steps in the manufacturing process in order to reduce the content of carcinogenic PAHs in olive oil.