城市污泥农用对不同土壤中有机污染物的影响

Effect of Sewage Sludge on Accumulation of Persistent Organic Pollutants in Soils

应用气相色谱(GC)和高效液相色谱(HPLC)技术对施用城市污泥盆栽植物后的土壤中的多氯联苯(PCBs)、有机氯农药(OCPs)、菲(PA)和苯并[a]芘(B[a]P)进行了系统分析,探讨不同土壤中有机污染物的含量变化情况。结果表明,不同处理土壤中检出的有机化合物,均以PCBs、OCPs和PA为主。强致癌性化合物苯并[a]芘在土壤中的含量远远低于加拿大和荷兰污染土壤治理标准的目标值(0.1 mg/kg和0.025 mg/kg)。PA在土壤中的检出率大大高于苯并[a]芘,但均低于加拿大土壤质量控制标准(0.1 mg/kg),极个别高于荷兰土壤质量控制标准(0.045 mg/kg)。城市污泥农用后均会造成土壤不同程度的有机污染物污染,有机污染物污染土壤的程度与污泥的性质、有机化合物的性质和土壤的性质等有关。

A pot experiment was carried out of Trifolium pretense and different soils treated with different types of sewage sludge. Three kinds of organic pollutants, including 19 compounds, such as polychlorinated biphenyls （PCBs）, organochlorine pesticides （OCPs） and polycyclic aromatic hydrocarbons （PAHs）, in the soils were systematically analyzed with the GC and HPLC techniques to investigate effects of the sludges on accumulation of organic pollutants in the tested soils. OCPs dominated in the soils and PCBs, PA, and B[a]P followed. Strongly carcinogenic B[a]P was detected in all the soils, but far below the criteria in the soil standards of Canada （0.1 mg/kg） and the Netherlands （0.025 mg/kg）. The contents of PA in the soils were much higher than B[a]P, but still below the criteria of the soil standards of Canadian （0.1 mg/kg） and only the contents of some individuals were high than criteria in the soil standards of the Netherlands （0.045 mg/kg）. Application of sewage sludge in farmland will lead to soil pollution with organic pollutants to a varying degree. Pollution degree is closely related to properties of sewage sludges, chemical compounds and soils.