Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084, P. R. China.
Environ Sci Process Impacts. 2015 Jun;17(6):1182-9. doi: 10.1039/c5em00177c. Epub 2015 May 22.
Wastewater reclamation and reuse is a promising way to relieve water scarcity by substituting for natural water consumption by industrial cooling. However, health concerns regarding cooling water originating from reclaimed water are increasing because an abundance of antibiotic-resistant bacteria (ARB) has been detected in reclaimed water. To assess the potential increase of ARB risks in reclaimed water after reuse for industrial cooling, the prevalence of six types of ARB was investigated in water and sediment samples from Lake Gaobeidian, which serves as an artificial circular storage reservoir for reclaimed water for cooling reuse. The effect of treated wastewater and cooling water drainage on the ARB distribution in water and sediment samples was also studied. The results showed that the concentration levels of six types of ARB in lake water samples were as high as those in treated wastewater. The annual median concentrations of total heterotrophic bacteria (HPC) and ARB in discharged cooling water after usage were 0.6-log and 0.4-log higher than those in treated wastewater and the cooling water intake site, respectively, indicating that the process of cooling water usage enhanced the proliferation of HPC and consequently increased the concentrations of ARB. Furthermore, the percentages of penicillin-, ampicillin-, and cephalothin-resistant bacteria in water were 30-57%, 36-48%, and 23-40% higher than those in sediment, respectively. However, the proportions of chloramphenicol-resistant bacteria in water were 35-85% lower than those in sediment. Quantitative evaluation of antibiotic resistance showed that HPC in water had a significant tolerance to penicillin and chloramphenicol, with 50% inhibitory concentrations reaching 22.90 mg L(-1) and 29.11 mg L(-1), respectively.
污水再生回用是缓解工业冷却用水消耗替代天然水资源的一种有前景的方法。然而，由于再生水中检测到大量的抗生素耐药菌（ARB），人们对来自再生水的冷却用水的健康问题越来越关注。为了评估工业冷却再利用后再生水中ARB 风险的潜在增加，本研究调查了作为再生水冷却再利用人工循环储存库的官厅水库水和沉积物样品中六种类型的 ARB 的流行情况。还研究了处理后的废水和冷却排水对水和沉积物样品中 ARB 分布的影响。结果表明，湖水样品中六种类型 ARB 的浓度与处理后的废水中的浓度一样高。使用后排放的冷却水中总异养菌（HPC）和 ARB 的年中值浓度分别比处理后的废水和冷却进水点高出 0.6-log 和 0.4-log，表明冷却水使用过程增强了 HPC 的增殖，从而增加了 ARB 的浓度。此外，水中青霉素、氨苄青霉素和头孢噻吩耐药菌的百分比分别比沉积物中的百分比高 30-57%、36-48%和 23-40%。然而，水中氯霉素耐药菌的比例比沉积物中的低 35-85%。抗生素耐药性的定量评价表明，水中的 HPC 对青霉素和氯霉素有显著的耐受性，半抑制浓度分别达到 22.90 mg L(-1)和 29.11 mg L(-1)。
