Nearly 80% of the population in the Colombo district fulfill their major requirement from the Kelani river. Recent studies are interoperating: most groundwater and surface water in Sri Lanka are contaminated with waterborne pathogens and antibiotics. In the present study, nine antibiotic resistance genes (ARGs) were screened which were belonging to two common groups of antibiotic: penicillin — OPR D, bla _TEM, bla _OXA, amp a, and amp b — and tetracycline — tet A, tet M, tet B, and tet S. The results of the study reveled that the surface and groundwater of the entire lower part of the Kelani river basin were contaminated with TC and FC (98%). None of the penicillin and tetracycline group antibiotics were detected either surface or groundwater samples except the Kelani river mouth (amoxicillin (AMX) at 0.003 ± 0.001 µg/ml). The results showed that 5 to 15% of surface water samples were positive for penicillin resistance genes (bla _TEM, bla _OXA, OPR D, amp a, amp b) where ~ 10% of groundwater samples were positive against tetracycline resistance genes (tet A, tet M, tet S, tet B). Among the penicillin resistance genes, the bla _TEM (700.576 × 10² copy/ml) was recorded as the highest concentration where the highest tet A gene (439.875 × 10² copy/ml) was detected among the tetracycline resistance genes. Therefore, water quality management and regular monitoring are essential to maintain the quality of drinking water in the meandering part of the Kelani river basin to safeguard river water consumers.

科伦坡地区近 80% 的人口通过克拉尼河满足了他们的主要需求。最近的研究是互操作的：斯里兰卡的大多数地下水和地表水都受到水源性病原体和抗生素的污染。在本研究中，筛选了九个抗生素抗性基因 (ARG)，它们属于两个常见的抗生素组：青霉素 — OPR D、bla _TEM、bla _OXA、amp a和amp b — 以及四环素 — tet A、tet M , tet B和tet S. 研究结果表明，整个克拉尼河流域下部的地表水和地下水都受到了 TC 和 FC（98%）的污染。除了克拉尼河口（阿莫西林 (AMX)，浓度为 0.003 ± 0.001 µg/ml），在地表或地下水样品中均未检测到青霉素和四环素类抗生素。结果表明，5%~15%的地表水样对青霉素抗性基因（bla _TEM , bla _OXA , OPR D , amp a , amp b）呈阳性，其中~10%的地下水样对四环素抗性基因呈阳性（tet A , tet M , tet S ,乙）。在青霉素抗性基因中，bla _TEM（700.576 × 10 ²拷贝/ml）被记录为最高浓度，其中在四环素抗性基因中检测到最高的tet A基因（439.875 × 10 ²拷贝/ml）。因此，水质管理和定期监测对于维持克拉尼河流域蜿蜒部分的饮用水质量以保护河水消费者至关重要。