Bright D A, Healey N
Applied Research, Royal Roads University, Victoria, British Columbia, Canada.
Environ Pollut. 2003;126(1):39-49. doi: 10.1016/s0269-7491(03)00148-9.
This study examines the potential for environmental risks due to organic contaminants at sewage sludge application sites, and documents metals and various potential organic contaminants (volatile organics, chlorinated pesticides, PCBs, dioxins/furans, extractable petroleum hydrocarbons, PAHs, phenols, and others) in current production biosolids from five wastewater treatment plants (WWTPs) within the Greater Vancouver Regional District (GVRD). There has been greater focus in Europe, North America and elsewhere on metals accumulation in biosolids-amended soil than on organic substances, with the exception of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans. Another objective, therefore, was to evaluate the extent to which management of biosolids re-use based on metal/metalloid levels coincidentally minimizes environmental risks from organic contaminants. Historical-use contaminants such as chlorophenols, PCBs, and chlorinated pesticides were not detected at environmentally relevant concentrations in any of the 36 fresh biosolids samples, and appear to have virtually eliminated from sanitary collection system inputs. The few organic contaminants found in freshly produced biosolids samples that exhibited high concentrations relative to British Columbia and Canadian soil quality benchmarks included p-cresol, phenol, phenanthrene, pyrene, naphthalene, and heavy extractable petroleum hydrocarbons (HEPHs--nCl9-C34 effective carbon chain length). It was concluded that, with the exception of these petroleum hydrocarbon constituents or their microbial metabolites, the mixing of biosolids with uncontaminated soils during land application and based on the known metal concentrations in biosolids from the Greater Vancouver WWTPs investigated provides adequate protection against the environmental risks associated with organic substances such as dioxins and furans, phthalate esters, or volatile organics. Unlike many other organic contaminants, the concentrations of petroleum hydrocarbon derived substances in biosolids has not decreased within the last decade or more in the WWTPs studied, and--unlike persistent chlorinated compounds--the associated PAHs and other hydrocarbon constituents merit careful consideration, especially in the context of repeated land-application of biosolid.
本研究调查了污水污泥施用场地因有机污染物而产生环境风险的可能性，并记录了大温哥华地区（GVRD）五家污水处理厂（WWTPs）当前生产的生物固体中的金属及各种潜在有机污染物（挥发性有机物、氯代农药、多氯联苯、二噁英/呋喃、可萃取石油烃、多环芳烃、酚类等）。在欧洲、北美及其他地区，相比于有机物质，人们更关注生物固体改良土壤中的金属积累，多氯代二苯并 - 对 - 二噁英和多氯代二苯并呋喃除外。因此，另一个目标是评估基于金属/类金属含量的生物固体再利用管理在多大程度上能同时将有机污染物带来的环境风险降至最低。在36个新鲜生物固体样品中，均未检测到环境相关浓度的历史使用污染物，如氯酚、多氯联苯和氯代农药，这些污染物似乎已从生活污水收集系统输入中基本消除。在新鲜生产的生物固体样品中发现的少数有机污染物，相对于不列颠哥伦比亚省和加拿大土壤质量基准而言浓度较高，其中包括对甲酚、苯酚、菲、芘、萘以及重质可萃取石油烃（HEPHs——nCl9 - C34有效碳链长度）。研究得出结论，除了这些石油烃成分或其微生物代谢产物外，在土地施用过程中，将生物固体与未受污染的土壤混合，并根据所调查的大温哥华污水处理厂生物固体中的已知金属浓度，可充分防范与二噁英和呋喃、邻苯二甲酸酯或挥发性有机物等有机物质相关的环境风险。与许多其他有机污染物不同，在所研究的污水处理厂中，生物固体中石油烃衍生物质的浓度在过去十年或更长时间内并未降低，而且——与持久性氯代化合物不同——相关的多环芳烃和其他烃类成分值得仔细考虑，尤其是在生物固体重复土地施用的情况下。
