Speciation of VOCs in the cooking fumes from five edible oils and their corresponding health risk assessments

Abstract

Cooking fumes are important volatile organic compounds (VOCs) sources of indoor air, however, emission characteristics of the commonly used oils (canola, soybean, peanut, corn and lard) in Chinese cooking and health risks of the corresponding VOCs are still not clear. In this study, we sprayed the oil droplets uniformly on a pre-heated wall via a nozzle in order to obtain the cooking fumes with constant VOC compositions. Our results show that emission profiles of VOCs are similar among the five oils. The vegetable oils rich in unsaturated fatty acids emit more VOCs than the lard oil rich in saturated fatty acids, and the VOCs emitted from the soybean oil increase with increasing cooking temperatures. Water in oils always enhances VOC emissions by steam stripping at high temperatures. Moreover, oxidative radicals generated in the water-oil system facilitate oxidation of unsaturated fatty acids, producing carcinogenic aldehydes, benzenes and furans in the emitted VOCs. The carcinogenic risk order of furan > nonanal > hexanal > heptanal > octanal> 2-nonenal > benzene indicates that furan and various aldehydes are more carcinogenic than benzene compounds. The comprehensive health risk factor further reveals that the carcinogenic risks of the emitted VOCs from the five oils follow the order of peanut > canola > soybean > corn >> lard.