Byrnes Neil Andrew, Silvester Reshma, Cross Gareth, Weightman Andrew J, Jones Davey L, Kasprzyk-Hordern Barbara
Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK; Centre of Excellence in Water-Based Early-Warning Systems for Health Protection, University of Bath, Claverton Down, Bath BA2 7AY, UK; Institute of Sustainability and Climate Change, University of Bath, Claverton Down, Bath BA2 7AY, UK; Australian Centre for Research on Separation Science, School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800, Australia.
School of Environmental and Natural Sciences, Bangor University, Bangor, Gwynedd LL57 2UW, UK.
Environ Int. 2025 Jun 20;202:109606. doi: 10.1016/j.envint.2025.109606.
Antimicrobial resistance (AMR) is a major public health concern. Antimicrobial residues enter wastewater where their continued presence can lead to an increased risk of AMR while also causing environmental harm when untreated wastewater is discharged into the environment. This research presents the antimicrobial residue surveillance results of a national-scale wastewater sampling campaign across Wales. Wastewater from 15 sites-effluent from 7 hospitals and influent from 8 community wastewater treatment plants-was collected for 5 consecutive days monthly from May-July 2023. This campaign captured more than 30 % of the Welsh population and over 30 % of the population receiving care as hospital inpatients. Using a quantitative approach, over 175 unique wastewater samples were analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for more than 40 antimicrobials including: β-lactams, macrolides, quinolones, sulfonamides, a veterinary antibiotic, an antifungal, antivirals, and numerous metabolites. The most prevalent antimicrobials were clarithromycin, its metabolite N-desmethyl clarithromycin, fluconazole, and trimethoprim as they were detected in all samples. Sulfamethoxazole concentrations ranged from 724-28031 ng/L and trimethoprim ranged from 785-44539 ng/L in hospital effluent-concentrations significantly higher than those reported in published literature. In hospital wastewater, many antimicrobials were present at concentrations which were orders of magnitude higher than their respective predicted no-effect concentrations (PNECs) for antibiotic resistance selection (e.g., metronidazole, trimethoprim). These concentrations create a selective pressure which can drive AMR emergence. Furthermore, some antimicrobials remained at high-risk concentrations even after dilution in community wastewater (e.g., ciprofloxacin, clarithromycin). Environmental risk assessments also identified clarithromycin and ciprofloxacin as agents of concern while vancomycin posed the highest environmental risk (concentrations ca. 1000-38000-fold > PNEC in hospital effluent) should this wastewater enter the environment untreated (e.g., combined sewer overflows). Instances of direct disposal of antimicrobials were clearly identified in hospital wastewater. These results demonstrate the importance of regular monitoring of AMR and potential environmental risk posed by antimicrobials in wastewater, while demonstrating the need for comprehensive national action (e.g., treatment of hospital wastewater on-site, tertiary/quaternary treatment of community wastewater, tailored stewardship programs, focussed control efforts on high-risk antimicrobials) to minimize risks to public health and the environment.
抗菌药物耐药性（AMR）是一个重大的公共卫生问题。抗菌药物残留进入废水，其持续存在会导致AMR风险增加，同时未经处理的废水排放到环境中也会造成环境危害。本研究展示了威尔士全国范围内废水采样活动的抗菌药物残留监测结果。2023年5月至7月，每月连续5天收集来自15个地点的废水——7家医院的污水和8个社区污水处理厂的进水。该活动覆盖了超过30%的威尔士人口以及超过30%接受住院治疗的人群。采用定量方法，通过超高效液相色谱串联质谱法（UPLC-MS/MS）对175多个独特的废水样本进行分析，检测了40多种抗菌药物，包括：β-内酰胺类、大环内酯类、喹诺酮类、磺胺类、一种兽用抗生素、一种抗真菌药、抗病毒药以及众多代谢物。最普遍的抗菌药物是克拉霉素、其代谢物N-去甲基克拉霉素、氟康唑和甲氧苄啶，因为它们在所有样本中均被检测到。医院污水中磺胺甲恶唑浓度范围为724 - 28031纳克/升，甲氧苄啶浓度范围为785 - 44539纳克/升——这些浓度显著高于已发表文献中报道的浓度。在医院废水中，许多抗菌药物的浓度比其各自预测的抗生素耐药性选择无效应浓度（PNECs）高出几个数量级（例如甲硝唑、甲氧苄啶）。这些浓度产生了一种选择压力，可推动AMR的出现。此外，一些抗菌药物即使在社区废水中稀释后仍处于高风险浓度（例如环丙沙星、克拉霉素）。环境风险评估还将克拉霉素和环丙沙星确定为关注对象，而万古霉素带来的环境风险最高（医院污水中的浓度比PNEC高约1000 - 38000倍），如果这些废水未经处理进入环境（例如合流制下水道溢流）。在医院废水中明确发现了直接排放抗菌药物的情况。这些结果表明定期监测AMR以及废水中抗菌药物带来的潜在环境风险的重要性，同时表明需要采取全面的国家行动（例如医院废水现场处理、社区废水三级/四级处理、量身定制的管理计划、针对高风险抗菌药物的重点控制措施），以将对公众健康和环境的风险降至最低。
