Survey of polycyclic aromatic hydrocarbons of vegetable oils and oilseeds by GC-MS in China

There is a lack of information regarding the occurrence and content of contamination of polycyclic aromatic hydrocarbon (PAH) in edible vegetable oils and oilseeds used for oil production in China. By combining the advantages of ultrasound-assisted extraction, low temperature separation and silica SPE purification, a method for the determination of the USEPA, 16 PAHs was developed based on GC-MS to fill this gap. The method recoveries for oils and oilseeds were 84.4-113.8% and 84.3-115.3%, respectively. The LODs and LOQs for 16 PAHs were ranged from 0.06-0.17 and 0.19-0.56 mu g kg(-1), respectively. Based on the established method, PAH concentrations in 21 edible oils and 17 oilseeds were determined. Almost all the PAHs were found in all the samples tested, especially the light PAHs (LPAHs). Three oil samples exceeded the maximum level of 10 mu g kg(-1) for BaP set by China. However, five and six oil samples, respectively, exceeded the maximum limits of 2 and 10 mu g kg (-1) set for BaP and PAH4 by the European Union. The concentrations of PAH16 in oilseed samples were 1.5 times higher than corresponding oil samples. The relationships between PAH4 and PAH8, PAH4 and PAH16 as well as PAH8 and PAH16 indicates that PAH4 is a sufficient surrogate for the contamination level of PAHs in edible oils when compared with PAH8.