城市污泥及其堆肥施用对通菜中有机污染物的累积效应

Effect of Sewage Sludge and Its Composts on the Accumulation of Organic Pollutants in Ipomoea aquatic Grown in Paddy Soil

在水稻土上施用城市污泥及其堆肥盆栽通菜 ,应用GC/MS联机检测技术对植株中 8类共 44种有机污染物进行系统分析 .结果表明 ,通菜中检出 2 8种有机化合物 ,主要是邻苯二甲酸酯类、硝基苯类和多环芳烃类化合物 .各类污染物均以个别或少数化合物为主 ,其它化合物的含量低得多或未检出 .施用污泥的通菜中有机污染物的含量普遍较高 ,是空白对照的数倍至数 1 0倍 ,而施用各种污泥堆肥的通菜中有机污染物的含量普遍较低 ,甚至低于空白对照 ,尤其是施用污泥加牛粪堆肥的通菜中仅检出 1种化合物 .因此 ,污泥直接施用可能导致作物中有机污染物的吸收累积 。

Eight kinds of organic pollutants including 44 compounds in Ipomoea aquatic grown in paddy soil fertilized with sewage sludge and its composts were systematically determined by GC/MS. The results showed that twenty eight compounds consisting mainly of phthalic acid esters, nitrobenzenes, and polycyclic aromatic hydrocarbons were detected in Ipomoea aquatic. Only individual or very few compounds for each kind of organic pollutants in Ipomoea aquatic were predominant, while others were trace or not detected. Compared with control, compounds detected in Ipomoea aquatic fertilized with sludge were commonly higher to a different extent, but those detected in Ipomoea aquatic fertilized with different sludge composts were commonly lower and even not detected, especially for Ipomoea aquatic fertilized with sludge + rice straw composts was detected only one compound. It was therefore concluded that direct use of sewage sludge as organic fertilizer could result in bioaccumulation of organic pollutants in crops, but sludge compost application would be safe if proper compost treatment for sludge was conducted.