Effect of plastic packages on benzo[a]pyrene concentration in sunflower oil

Abstract

Commercially available sunflower oil and the same oil distilled additionally in a molecular evaporator (to remove naturally occurring compounds) was spiked with benzo[a]pyrene (BaP) at the levels of 37.1 and 38.6 μg/kg, respectively. Then, it was filled into polyethylene terephtalate (PET) and low density polyethylene (LDPE) receptacles of cylindrical shape, and BaP concentration was followed within 49 h. At the end of the experiments, BaP concentration in the non-distilled oil packed into PET decreased to 25.9 μg/kg, and BaP concentration in the distilled oil decreased to 34.6 μg/kg. The rate and the extent of BaP removal were evaluated comparing the diffusion and equilibrium coefficients. The results showed that PET is able to reduce BaP concentration in sunflower oil due to BaP sorption on the PET surface, but the rate and the extent of BaP removal are also affected by other compounds present in the oil. As found, LDPE is an inappropriate material for the BaP removal from sunflower and rapeseed oils, because BaP concentration in the oils remained at a constant level during the whole experiment.