摘要
地下式污水厂因空间较为封闭可能聚集较高浓度的微生物气溶胶,从而对员工身体健康造成威胁.本研究选取某典型地下式污水厂作为研究对象,监测厂内细菌气溶胶的浓度和粒径分布特征,并通过非致癌风险商(HQ)和定量微生物风险评估(QMRA)方法对其健康风险进行评价.结果表明:①该地下式污水厂各处理单元细菌气溶胶平均浓度范围为86~736 CFU·m^(-3),低于传统地上污水厂A^(2)O工艺、氧化沟工艺和SBR工艺的浓度水平;②在预处理区、污泥脱水区和生化池缺氧区检测到大肠杆菌、沙门氏菌和金黄色葡萄球菌,其浓度范围分别为3~17、3~12和5~8 CFU·m^(-3);③各处理单元的细菌气溶胶粒径在Anderson六级采样器各级范围分布较平均,其中,可吸入颗粒物(<4.7μm)占比为64%~70%,预处理区可吸入细菌占比最高,生化池缺氧区次之,污泥处理区最低;④细菌气溶胶造成的厂内所有区域和工种的非致癌风险商均低于1,细菌气溶胶对人体的非致癌风险较小;⑤QMRA结果表明,金黄色葡萄球菌年感染风险部分超出EPA基准(10^(-4) pppy),沙门氏菌年感染风险则显著高于该基准,造成的健康风险极大,需要重点监测防控.
Bioaerosols are generated during the operation of wastewater treatment plants,and underground wastewater treatment plants may accumulate more bioaerosols due to the enclosed space,which may threaten the health of employees.In this study,the concentrations and particle size distributions of bacterial aerosols in an underground wastewater treatment plant were monitored,and the health risk was evaluated by the non-carcinogenic risk assessment and quantitative microbial risk assessment(QMRA)methods.The results showed that:①the average concentration of bacterial aerosols in each treatment unit of this underground wastewater treatment plant was 86~736 CFU·m^(-3),which was lower than that of A^(2)O process,oxidation ditch process,and SBR process in the traditional aboveground wastewater treatment plant;②E.coli,Salmonella,and Staphylococcus aureus were detected in the pre-treatment area,the sludge dewatering area,and the anoxic area of the biochemical tank,and the concentration was 3~17 CFU·m^(-3),3~12 CFU·m^(-3),and 5~8 CFU·m^(-3),respectively;③the particle sizes of the bacterial aerosol in each treatment unit were distributed evenly at all levels of 6-stage Anderson sampler,with respirable particulate matter(<4.7μm)accounting for 64%~70%,and the proportion of inhalable bacteria in the pretreatment area was the highest,followed by the anoxic area of the biochemical tank,and that in the sludge treatment area was the lowest;④the non-carcinogenic risk quotient caused by bacterial aerosols is lower than 1 for all areas and workers in the plant,indicating that the non-carcinogenic risk of bacterial aerosols to human beings is small;⑤the QMRA results indicate that the annual risk of Staphylococcus aureus partially exceeds the EPA benchmark(10^(-4) pppy),and the annual risk of Salmonella infection is significantly higher than the benchmark,which poses a significant health risk and the monitoring and prevention is needed.
作者
张璐晶
邓子祺
李威龙
陈昕悦
郑祥
庞洪涛
侯锋
程荣
曹效鑫
ZHANG Lujing;DENG Ziqi;LI Weilong;CHEN Xinyue;ZHENG Xiang;PANG Hongtao;HOU Feng;CHENG Rong;CAO Xiaoxin(Xinkai Water Environment Investment Co.,Ltd,Beijing 101101;College of Chemistry and Life Resources,Renmin University of China,Beijing 100872;Guizhou Zhuxin Water Environment Industries Co.,Ltd,Guiyang 550081)
出处
《环境科学学报》
CAS
CSCD
北大核心
2024年第11期62-69,共8页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.52070192)
北京市自然科学基金(No.8232036)。
关键词
细菌气溶胶
地下式污水厂
分布特征
定量微生物风险评估
bacterial aerosols
underground wastewater treatment plants
distribution
quantitative microbial risk assessment
