城市污泥和化肥对水稻土种植的通菜中多环芳烃(PAHs)的影响

Effect of Municipal Sludges and Chemical Fertilizer on the Occurrence of Polycyclic Aromatic Hydrocarbons in Ipomoea aquatic Grown in Paddy Soil

在水稻土上施用城市污泥和化肥盆栽通菜 ,应用 GC/MS联机检测技术对通菜中 1 7种多环芳烃化合物进行了分析。结果表明 ,各处理通菜中的 ∑ PAHs含量在 0 .4 1 4～ 5 .4 0 4 mg/kg之间 ,依次是佛山污泥 +化肥 >广州污泥 +化肥>化肥 >广州污泥 >佛山污泥 >空白 ;致癌性 PAHs化合物的总含量 ( ∑ PAHscarc)在 0 .0 6 8～ 0 .94 4mg/kg之间。绝大部分化合物在通菜中的含量大于在根系中的含量。与空白对照相比 ,施用城市污泥和化肥均使通菜中的 ∑ PAHs含量明显提高。各处理通菜中的 PAHs都只是以一种或几种化合物为主 ,主要是 3、4个苯环的化合物 ,显示不同的分布特征。

Seventeen compounds of polycyclic aromatic hydrocarbons (PAHs) in Ipomoea aquatic potted in paddy soil fertilized with municipal sludges and chemical fertilizer in greenhouse were determined by GC/MS. The results showed that the total contents of PAHs ( ∑ PAHs) in Ipomoea aquatic (aboveground) grown in varied treatments ranged from 0.414mg/kg to 5.404mg/kg, decreased in the order of Foshan sludge + fertilizer (5.404mg/kg)>Guangzhou sludge + fertilizer (2.291mg/kg)>fertilizer (1.961mg/kg)>Guangzhou sludge (1.339mg/kg)>Foshan sludge (0.747mg/kg)>control (0.414mg/kg), and the contents of carcinogenic PAHs compounds ( ∑ PAHs_ carc ) were between 0.068 mg/kg and 0.944 mg/kg, decreased in the order of Guangzhou sludge + fertilizer (0.944mg/kg) >fertilizer (0.372mg/kg)>Foshan sludge + fertilizer (0.338mg/kg) >Foshan sludge (0.311mg/kg)>Guangzhou sludge (0.224mg/kg)>control (0.68mg/kg). Bioconcentration of PAHs in Ipomoea aquatic fertilized with sludges and fertilizer increased to a different extent compared with control, nearly one times to six times higher for ∑ PAHs, and three times to six times higher for ∑ PAHs_ carc . The contents of ∑ PAHs, ∑ PAHs_ carc , and most PAHs compounds in roots were all lower than those of which in plant (aboveground). Contents of different PAHs compounds in each treatment of Ipomoea aquatic varied significantly, only one or several of PAHs compounds usually belonging to 3-benzene ring or 4-benzene ring compounds such as phenanthrene, fluoranthrene, anthracene,benz(a)anthracene were predominant, while those compounds belonging to 2-benzene ring, 5-benzene ring, and 6-benzene ring were usually minor or even under detection limit, which displayed different distribution patterns of PAHs compounds.