Study On Analysis Methodology Of Polycyclic Aromatic Hydrocarbons And Halogenated Polycyclic Aromatic Hydrocarbon Residues In Agricultural Products And Application

Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic pollutants (POPs) which may lead to carcinogenesis, teratogenesis and mutagenesis. Residue of PAHs in food was highlighted in the world in recent years, and a number of researches have indicated that70%PAHs exposure pathways may stem from food. Therefore, study on PAHs in food is important. Halogenated polycyclic aromatic hydrocarbons (X-PAHs), as the derivative of PAHs, had been detected in drinking water which showed the similar toxicity with dioxin. However, there is almost no study on it in food. Due to the carcinogenicity of polycyclic aromatic hydrocarbon compounds, and they are widely existence in food and environment, it is important to monitor and make risk assessment of polycyclic aromatic hydrocarbons and derivatives in food.In this experiment, firstly, a method was developed for determination of16polycyclic aromatic hydrocarbons and11halogenated polycyclic aromatic hydrocarbons in vegetables, corn and other agricultural products by gas chromatography-tandem mass spectrometry (GC-MS/MS). The analytes were extracted from the samples by hexane, and purified by dispersion solid phase extraction using PSA and C18sorbent, then analyzed by gas chromatography-tandem mass spectrometry (GC-MS/MS) and used external standard method. The recoveries were in the range of74.7%-115.1%, and the relative standard deviation (RSD) were1.6%-15.3%at50μg/kg、100μg/kg and200μg/kg three spiked levels for16polycyclic aromatic hydrocarbons and11halogenated polycyclic aromatic hydrocarbons. The limits of determination (LOD) for all analytes were between0.001μg/kg and0.25μg/kg. The limits of quantification (LOQ) were between0.004μg/kg and0.83μg/kg.According to the above, we carried out research about the remainess level of PAHs and X-PAHs in vegetable, corn and other agricultural products in Beijing’s major supermarkets and farmers’ markets. In this experiment,80vegetables and8corn samples were selected at random. The main results were list as follows:(1) Different levels of PAHs and X-PAHs were detected in all samples, and the concentration of PAHs were higher than X-PAHs. The level of total PAHs detected in vegetable sampeles was between from18.18μg/kg to55.37μg/kg, the level of total X-PAHs was between from18.18μg/kg to55.37μg/kg. The mean concentration of PAHs in soybean was47.7μg/kg, which was higher than corn of44.3μg/kg, the total concentration of X-PAHs in soybean and corn samples were0.62μg/kg,0.71μg/kg, respectively.(2) According to the vegetable categories, the level of total PAHs and X-PAHs detected in leaf vegetables was higher than root vegetables. According to source and packaging, the highest level of total PAHs and X-PAHs was detected in vegetables of farmer’s market, followed by vegetables of supermarket and packaged vegetable Analysis a single compound which was detected from vegetables:PAHs with the lower molecular weights (LMW) had higher detection rates, while the higher molecular weights (HMW) had lower detection rates. Among the sixteen target PAHs, the eight LMW PAHs (Nap, Acy, Ace, Fle, Phe, Ant, Flu and Pyr) were detected in more than90%of the vegetable samples. NaP, Phe and Fle were the three predominant PAHs congeners in all vegetable samples, which collectively accounted for74.2-75.6%of∑16PAHs.The total daily intake of PAHs and X-PAHs via vegetables from the different gender and age group in Beijing were investigated in this study. The results indicated that people of different age and gender show different exposure levels on the same target compound. Males showed slightly higher exposure dose than females, which is mainly reason caused by the weight differences and diet differences of the person. According to age, the ranking of daily intake exposure in decreasing order was:adults, seniors, adolescents, children, for both males and females.According to our country’s nutritional dietary structure, the incremental lifetime cancer risk (ILCR) model was applied to assess the dietary exposure of PAHs and X-PAHs in vegetable. We firstly carried out cancer risk assessment of PAHs and X-PAHs in vegetable, and the risk halogenate derivatives of PAHs was firstly considered, thus the risk assessment was more accurate. The results were listed as follows:cancer risk level of young people was higher than that of older. According to age, the ranking of ILCR in decreasing order was:children, adolescents, adults, seniors for both males and females. Children were the most sensitive population to PAHs and X-PAHs, and their health issues should be paid more attention. The median values of PAHs ILCRs for all population groups fell within the range of10-6-10-5, being higher than the acceptable risk level (10-6) and lower than the priority risk level (10-4). ILCR values of X-PAHs lower than the acceptable risk level (10-6) and less than10-7which implied less cancer risk.