Accumulation characteristics and potential risk of PAHs in vegetable system grow in home garden under straw burning condition in Jilin, Northeast China

Abstract

The accumulation characteristics and potential risk posed by polycyclic aromatic hydrocarbons (PAHs) in soils and vegetables grown in the home garden and agricultural field were investigated in this research. The average concentrations of 16 PAHs in soils and vegetables in the home garden were 508.9 ng/g and 197.3 ng/g, respectively, and in agricultural fields were 589.9 ng/g and 171.3 ng/g, respectively. The 16 PAHs concentrations of vegetables in the home garden were a little higher than in agricultural field. The most abundant PAHs in soils and vegetables was Phe, followed by Fla and Pyr in our study area. The concentrations of low-molecular-weight PAHs (L-PAHs) were higher in vegetables as compared to higher molecular weight 4–6 ring PAHs (H-PAHs). The results of plant concentration factor (PCF) indicated that L-PAHs have greater mobility in our research. Based on the results of PAH ratios, the main sources of the PAHs in soils were determined to be the combustion of biomass, coal, and petroleum. The total values of incremental lifetime cancer risk (ILCR) for males and females induced by soils and vegetables in home garden and agricultural field were all about 10−7 and 10−10. All the ILCRs value were lower than the baseline value, indicated that the carcinogenic risk for the soils and vegetables contaminated with PAHs in our study area for the residents was negligible.