城市污泥对通菜-水稻土中有机污染物的累积效应

Effect of municipal sludge on the accumulation of organic pollutants in Ipomoea aquatic plant-paddy soil

在水稻土上施用城市污泥及化肥盆栽通菜,应用GC/MS对通菜植株和土壤中的邻苯二甲酸酯(PAEs)和多环芳烃(PAHs)等7类43有机污染物进行系统分析,探讨通菜植株和土壤中其累积效应.结果表明,通菜植株中检出邻苯二甲酸酯、多环芳烃、氯苯类、硝基苯类、醚类和卤代烃类共6类28种化合物(胺类未检出),土壤中检出上述7类33种化合物,均以PAEs和PAHs为主,其总含量是其他类污染物的几倍或数十倍.不同处理的通菜和土壤中各类有机污染物的含量差别较大,均以个别或少数污染物为主.施用城市污泥增加了植株和土壤中PAEs和PAHs等污染物的含量.强致癌性化合物苯并(a)芘在通菜中被检出,在部分土壤中的含量超过加拿大土壤质量控制标准(1.0mg/kg).除佛山污泥处理的通菜对氯苯类和醚类的生物浓缩系数(BCF)大于1外,其余均小于1.0.

Ipomoea aquatic plant was grown in a pot of paddy soils with municipal sludge and chemical fertilizer. Seven kinds of organic pollutants including 43 compounds such as phthalic acid esters (PAEs), polycyclic aromatic hydrocarbon (PAHs), etc. in the Ipomoea aquatic plant and the soils were systematically analyzed with GC/MS to investigate the effect of the sludge and the fertilizers on accumulation of organic pollutants in Ipomoea aquatic plant and the soil. There were 28 compounds including PAEs, PAHs, chlorobenzenes, nitrobenzenes, ethers and halogenated hydrocarbons, etc. were detected in Ipomoea aquatic plant (amines not detected); and in pot soil 33 compounds were detected, in which PAEs and PAHs were predominant with their total content more than several or several ten times of the other pollutants. Contents of individual pollutant in different treatments of Ipomoea aquatic plant and pot soil varied greatly, with one or very few pollutants predominant. The contents of pollutants PAEs, PAHs, etc. in the plant and the soil fertilized with municipal sludge increased; strongly carcinogenic Benzo (a) pyrene was detected in Ipomoea aquatic plant and higher than Canadian soil standard (1.0mg/kg) in part of the soil. Except the bioconcentration factors (BCFs) of Foshan sludge treated Ipomoea aquatic plant to chlorobenzenes and ethers were more than 1.0, all the others were less than 1.0.