钢铁工业区附近农田蔬菜PAHs的浓度水平及分布

分析了钢铁工业区附近农田蔬菜的PAHs污染状况,发现8种蔬菜可食用部分的15种PAHs总浓度为227.1～1?533.2 ng/g,平均为759.1 ng/g,8种可疑致癌多环芳烃(BaA、Chr、BbF、BkF、BaP、DahA、BghiP、IcdP)的总浓度为7.1～231.2 ng/g,平均达70.6 ng/g.蔬菜可食用部分PAHs的含量为叶菜类>果菜类>肉质根茎类.果菜类和根茎类蔬菜可食用部分的PAHs大多富集在果（根）皮上,皮中PAHs浓度约为肉中的3倍.植物积累PAHs的能力与其脂肪含量呈正相关,脂肪含量对叶片吸收亲脂性高的化合物影响较大,而对根部吸收的影响则相反.脂肪含量相近时,表面粗糙或具有细密绒毛的叶片富集PAHs的能力较强,须根系根吸收PAHs的能力比直根系根强.

Concentration and Distribution of PAHs in Vegetables Grown near an Iron and Steel Industrial Area

Concentrations of 15 kinds of polycyclic aromatic hydrocarbon (PAHs) were determined in 8 vegetable species and their growing environment (soil and atmosphere) near an iron and steel industrial area. The total concentrations of 15 kinds of PAHs (sigma PAHs) were 227.1 - 1 533.2 ng/g, 759.1 ng/g in average. The concentrations of 8 carcinogenic PAHs (sigma carePAHs) were 7.1 - 231.2 ng/g, 70.6 ng/g in average. Of the various vegetable species determined, the highest polyaromatic burden was observed in the leafy vegetables, followed by melon and fruit species, while the rhizome species accumulated the lowest amount. In melon and fruit species, most PAHs were accumulated on the peel, only about 30% transfer into the core. The ability of the plant accumulating PAHs was mainly influenced by the lipid content of the plant. Leaf with pubescence or rough surface was found to have higher sigma PAHs than the other, and the fibre higher than the taproot, when the lipid contents were close.