由于存在耐多药细菌,山谷地表水被认为是重点关注的公共卫生问题。地表水中抗生素耐药性(AMR)细菌的分布受多种因素的影响,包括来自废水排放或药物等其他污染源的抗生素,杀生物剂,和重金属。此外,有证据表明,在重金属胁迫的影响下,高水平的抗生素抗性基因(ARGs)可以在细菌群落内转移。因此,这项研究的主要目的是调查利雅得WadiHanifah山谷上游和下游位置的重金属和细菌性ARGs的存在,沙特阿拉伯。总共在山谷内的18个地表水点进行了样品收集。ARGs的选择与最常见的抗生素有关,包括β-内酰胺,四环素,红霉素,庆大霉素,磺酰胺,氯霉素,万古霉素,甲氧苄啶,和粘菌素抗生素,使用聚合酶链反应(PCR)技术对其进行定性检测。测试的抗生素抗性基因(ARGs)包括(blaNDM-1(用于抗生素类β-内酰胺酶),mecA(耐甲氧西林金黄色葡萄球菌),tet(M)和tet(B)(对于抗生素类四环素),ampC(用于抗生素类β-内酰胺酶),vanA(万古霉素类抗生素),mcr-1(用于抗生素类粘菌素),erm(B)(用于抗生素类红霉素),aac6'-Ie-aph2-Ia(用于抗生素类庆大霉素),sulII(用于抗生素类磺酰胺),catII(用于抗生素类氯苯),和dfrA1(用于抗生素甲氧苄啶)。此外,对锂(Li)等重金属水平的评估,铍(Be),铬(Cr),钴(Co),砷(As),镉(Cd),锡(Sn),汞(Hg),采用电感耦合等离子体质谱法(ICPMS)对铅(Pb)进行分析。根据我们的发现,磺酰胺的浓度,红霉素,和氯霉素ARGs(erm(B),sulII,和catII)被观察到最高。相反,两个ARG,即mecA和mcr-1,在样品中未检测到。此外,我们的数据表明,与WadiHanifahValley下游站点的水样相比,上游站点的水样中细菌中的ARG显着增加。Li的平均浓度,Be,Cr,Co,As,Cd,Sn,Hg,水样中的铅估计为37.25微克/升,0.02µg/L,0.56微克/升,0.32微克/升,0.93微克/升,0.01µg/L,200.4µg/L,0.027µg/L,和0.26µg/L,分别,选定的18个地点。此外,据透露,从不同地点收集的水样中筛选的重金属浓度没有超过世界卫生组织(世卫组织)设定的最高限值。总之,这项研究提供了从利雅得WadiHanifah山谷获得的水样中重金属和ARGs的存在的简要概述,KSA这些发现将有助于持续监测和未来对ARGs在地表水中传播的风险评估。
Valley surface water is considered a focal public health concern owing to the presence of multi-drug-resistant bacteria. The distribution of antimicrobial resistance (AMR) bacteria in the surface water is affected by the presence of multiple factors, including antibiotics coming from wastewater discharge or other contaminant sources such as pharmaceuticals, biocides, and heavy metals. Furthermore, there is evidence suggesting that high levels of antibiotic resistance genes (ARGs) can be transferred within bacterial communities under the influence of heavy metal stress. Hence, the primary aim of this study is to investigate the presence of heavy metals and bacterial ARGs in upstream as well as downstream locations of Wadi Hanifah Valley in
Riyadh, Saudi Arabia. Sample collection was conducted at eighteen surface water sites within the valley in total. The selection of ARGs was associated with the most common antibiotics, including β-lactam, tetracycline, erythromycin, gentamicin, sulphonamide, chloramphenicol, vancomycin, trimethoprim, and colistin antibiotics, which were detected qualitatively using polymerase chain reaction (PCR) technology. The tested antibiotic resistance genes (ARGs) included (blaNDM-1 (for the antibiotic class Beta-lactamases), mecA (methicillin-resistant Staphylococcus aureus), tet(M) and tet(B) (for the antibiotic class Tetracycline), ampC (for the antibiotic class Beta-lactamases), vanA (for the antibiotic class vancomycin), mcr-1 (for the antibiotic class colistin), erm(B) (for the antibiotic class erythromycin), aac6\'-Ie-aph2-Ia (for the antibiotic class Gentamicin), sulII (for the antibiotic class sulphonamide), catII (for the antibiotic class Chlorophincol), and dfrA1 (for the antibiotic class trimethoprim). Moreover, an assessment of the levels of heavy metals such as lithium (Li), beryllium (Be), chromium (Cr), cobalt (Co), arsenic (As), cadmium (Cd), tin (Sn), mercury (Hg), and lead (Pb) was conducted by using inductively coupled plasma mass spectrometry (ICPMS). According to our findings, the concentrations of sulphonamide, erythromycin, and chloramphenicol ARGs (erm(B), sulII, and catII) were observed to be the most elevated. Conversely, two ARGs, namely mecA and mcr-1, were not detected in the samples. Moreover, our data illustrated a significant rise in ARGs in the bacteria of water samples from the upstream sites as compared with the water samples from the downstream sites of Wadi Hanifah Valley. The mean concentration of Li, Be, Cr, Co, As, Cd, Sn, Hg, and Pb in the water samples was estimated to be 37.25 µg/L, 0.02 µg/L, 0.56 µg/L,0.32 µg/L, 0.93 µg/L, 0.01 µg/L, 200.4 µg/L, 0.027 µg/L, and 0.26 µg/L, respectively, for the selected 18 sites. Furthermore, it was revealed that the concentrations of the screened heavy metals in the water samples collected from various sites did not surpass the maximum limits set by the World Health Organization (WHO). In conclusion, this study offers a concise overview of the presence of heavy metals and ARGs in water samples obtained from the Wadi Hanifah Valley in
Riyadh, KSA. Such findings will contribute to the ongoing monitoring and future risk assessment of ARGs spread in surface water.