城市污泥农用对植物和土壤中有机污染物的影响

Effect of Municipal Sludge on the Accumulation of Persistent Organic Pollutants in Different Plant-Soil Systems

应用GC和HPLC检测技术对施用城市污泥盆栽不同植物(雪韭、三叶草和紫花苜蓿)后的植物和土壤中的4种有机污染物(多氯联苯、有机氯农药、菲和苯并[a]芘)进行了系统分析,探讨不同植株、根系和土壤中有机污染物的含量变化情况。结果表明,供试植株、根系和土壤中均检出多氯联苯(PCBs)、有机氯农药(OCPs)和多环芳烃(菲和苯并[a]芘)等3类共19种有机化合物,其中均以OCPs、PCBs和菲(PA)为主。施用污泥不同程度地增加了大部分处理植物和土壤中PCBs、OCPs和PAHs(PA和B[a]P)等的含量。强致癌性化合物苯并[a]芘在各处理植株和根系中均被少量检出,在土壤中的检出量远远低于加拿大土壤质量控制标准(0.1mg·kg-1),仅个别处理高于荷兰污染土壤治理标准的目标值(0.025mg·kg-1)。菲在土壤、植株和根系中的检出量均大大高于苯并[a]芘,在部分土壤中的检出量超过加拿大和荷兰土壤质量控制标准(0.1和0.045mg·kg-1)。除个别污泥处理的不同植物对有机氯农药和多环芳烃类(菲)的生物浓缩系数(BCF)小于1.0、多环芳烃类(苯并[a]芘)大部分小于1.0外,其余均大于1.0。

Trifolium pretense, Alfalfa medicago sativa and A llium tuberosum were grown in pots with soils treated by municipal sludge. Three kinds of organic pollutants including 19 compounds such as polychlorinated biphenyls （PCBs）, organochlorine pesticides （OCPs） and polycyclic aromatic hydrocarbons （PAHs） in different plant-soil systems were systematically analyzed by using GC and HPLC, to investigate the effect of the sludge on the accumulation of persistent organic pollutants in the plants and the soils. There were 19 compounds including PCBs, OCPs and two PAHs （PA and B[a]P） were detected in all plants; and in pot soils 19 compounds were detected, among which PCBs, OCPs and PA were predominant with their total contents more than several or tens times of the other pollutants （B[a]P）. Contents of individual pollutant varied greatly with different plants and pot soils, with one or very few pollutants being predominant. The contents of PCBs, OCPs and the other pollutants in the plants and the soils fertilized with municipal sludge increased; strongly carcinogenic B[a]P was detected in the plants, much lower than Canadian soil standard （0.1 mg·kg^-1） in parts of the soils, and a few were higher than the soil standard of Holland （0.025 mg·kg^-1）. Another PAH, PA was detected in all plants, and its contents were higher than Canadian soil standard （0.1 mg·kg^-1） and the soil standard of Holand （0.045 mg·kg^-1） in part of the pot soils. The contents of PA in all the plants and pot soils were much higher than those of B[a]P detected. Except that the bioconcentration factors （BCFs） of some plants treated with sludge to OCPs, part of PA and most B[a]P were less than 1.0, all the others were more than 1.0.