Kozajda Anna, Jeżak Karolina
Nofer Institute of Occupational Medicine, Łódź, Poland (Department of Physical Hazards).
Med Pr. 2020 May 15;71(3):265-278. doi: 10.13075/mp.5893.00946. Epub 2020 Apr 27.
The aim of the study was to assess the occupational exposure to bacteria, including methicillin- resistant (MRSA) and other antibiotic-resistant strains in the municipal wastewater treatment plants (WWTPs) environment.
In 16 WWTPs in Poland, 33 wastewater and 253 air samples were collected in the spring-summer season. The microbiological analysis was carried out using a chromogenic medium. Species identification was carried out using the matrix assisted laser desorption ionization time-of-flight method, while the antibiotic-resistance analysis was performed with an automatic method.
Among 2805 bacterial isolates from the air and wastewater, 574 were identified as species (20.5%). The presence of species was found in 11 WWTPs (69%), among them in 11 WWTPs in raw wastewater and in 1 WWTP additionally in treated wastewater. The concentrations of in wastewater ranged 2-1215 colony-forming units per milliliter (CFU/ml). In the air, 2 isolates were identified in concentrations of 5 and 10 CFU/m; both samples were collected at the stage of mechanical wastewater treatment. The results revealed the following trend: the higher the outdoor temperature, the bigger the number of WWTPs with confirmed presence. Among 149 isolates (2 from the air and 147 from wastewater, including 2 MRSA), 100 isolates were resistant only to penicillin, while 34 isolates showed multi-antibiotic resistance (to penicillin and other drugs). It was found that isolated bacteria were resistant almost strictly to critical and highly important antibiotics in veterinary medicine.
In general, WWTPs workers are occupationally exposed to , including MRSA, and other antibiotic- and multi-antibiotic-resistant strains. The highest risk of infection concerns the activities carried out in direct contact with wastewater or devices through which wastewater flows, particularly at the stage of mechanical treatment. A significant source of seems to be intensive livestock farming located in the area of the WWTPs under analysis. The study confirms the necessity to disinfect the wastewater discharging into WWTPs. Med Pr. 2020;71(3):265-78.
本研究旨在评估市政污水处理厂环境中对细菌的职业暴露情况，包括耐甲氧西林金黄色葡萄球菌（MRSA）和其他耐抗生素菌株。
在波兰的16家污水处理厂中，于春夏季采集了33份废水样本和253份空气样本。使用显色培养基进行微生物分析。采用基质辅助激光解吸电离飞行时间法进行菌种鉴定，同时用自动方法进行抗生素耐药性分析。
在从空气和废水中分离出的2805株细菌中，有574株被鉴定为菌种（20.5%）。在11家污水处理厂（69%）中发现了菌种的存在，其中11家污水处理厂的原废水中有菌种，另外1家污水处理厂的处理后废水中也有菌种。废水中菌种的浓度范围为每毫升2 - 1215个菌落形成单位（CFU/ml）。在空气中，在机械污水处理阶段采集的两个样本中分别鉴定出浓度为5和10 CFU/m³的2株菌种。结果显示出以下趋势：室外温度越高，确认有菌种存在的污水处理厂数量越多。在149株菌种分离株（2株来自空气，147株来自废水，包括2株MRSA）中，100株分离株仅对青霉素耐药，而34株分离株表现出多重抗生素耐药性（对青霉素和其他药物）。发现分离出的细菌几乎严格对兽医学中关键和非常重要的抗生素耐药。
总体而言，污水处理厂工人在职业上会接触到包括MRSA在内的菌种以及其他耐抗生素和多重耐抗生素菌株。感染风险最高的是与废水或废水流经的设备直接接触的活动，特别是在机械处理阶段。在所分析的污水处理厂区域内，集约化畜牧业似乎是菌种的一个重要来源。该研究证实了对排入污水处理厂的废水进行消毒的必要性。《医学实践》。2020年；71(3):265 - 78。
