安徽省典型城市周边土壤-蔬菜中PAHs的污染特征

Characteristics of PAHs Contamination in Soil and Vegetable in Typical City Outskirt of Anhui Province,China

研究了安徽省合肥、芜湖和亳州市周边蔬菜地土壤和蔬菜中PAHs的含量及其污染特征。结果表明:安徽省典型蔬菜地土壤中15种PAHs(除萘外)的残留总量在58.2～437.8μg·kg-1之间,三环和四环PAHs占PAHs残留总量的70%以上。胡萝卜、菠菜和茄子体内15种PAHs的含量在23.4～209.1μg·kg-1之间,均值为120.7μg·kg-1,三环和四环PAHs占蔬菜中PAHs富集总量的92.8%～94.4%。不同蔬菜体内8种可疑性致癌PAHs的含量在11.5～17.4μg·kg-1之间,分别占蔬菜中PAHs残留总量的9.80%～13.8%,其中BaP含量在1.69～2.03μg·kg-1之间,低于国家对食品中污染物(BaP)的限量标准(5μg·kg-1)。不同类型PAHs在蔬菜体内的富集系数在0.10～9.20之间,极差达10倍以上,低分子量PAHs在蔬菜体内的富集系数要大于高分子量PAHs。不同PAHs在蔬菜体内的富集系数表现为胡萝卜>菠菜>茄子,其中芴在蔬菜体内的富集系数最高。

Residual levels of polyaromatic hydrocarbons（PAHs）in 38 vegetable soils,as well as bioaccumulation of PAHs from soils to different vegetables in Hefei,Wuhu and Bozhou cities of Anhui Province were investigated by using accelerated solvent extraction and high performance liquid chromatography methods.Results revealed that the levels of total 15 PAHs（except Nap）in surface soils（0～20 cm）collected from different vegetable bases were ranged from 58.2 μg·kg-1 to 437.8 μg·kg-1,and the amounts of three and four rings PAHs were more than 70% of the total PAHs tested in soils.The contents of 15 PAHs in carrot,spinach and eggplant were ranged from 23.4 μg·kg-1 to 209.1 μg· kg-1 with the mean level of 120.7 μg·kg-1.The quantities of low molecular PAHs（three and four rings）were higher than the high molecular PAHs（five and six rings）detected in vegetables,and three and four rings PAHs were between 92.8% and 94.4% of the total PAHs detected in vegetables.Eight carcinogen PAHs contents were ranged from 11.5 μg·kg-1 to 17.4 μg·kg-1,occupying 9.80% to 13.8% of total PAHs tested in vegetables.The contents of BaP in vegetables were lower than the Chinese standard limits of 5 μg·kg-1 in food.The bioaccumulation factors（BAFs）of 15 PAHs in different vegetables were ranged from 0.10 to 9.20,and the highest BAFs of PAHs in vegetables were ten times higher than the lowest one.The BAFs of PAHs in vegetable were in the order of：carrotspinacheggplant.The highest BAFs in vegetable were Fle,which was 9.20,7.07 and 5.48 in carrot,spinach and eggplant respectively.Results from this study provided invaluable data for judging soil quality and vegetable safety in Anhui Province of China.