16S rRNA gene sequence-based metagenomics assessment of microbial community structure and hospital wastewater chemical impacts on urban river

Aim: To assess the impact of hospital wastewater–associated contamination on the microbial diversity and community structure of sediments in urban river systems. Methodology: Sediment samples were collected from hospital-contaminated urban river sites. Physico-chemical characteristics of sediments, including pH, total organic carbon, and heavy metal concentrations, were determined using standard protocols. The Composition and diversity microbial community were analysed by 16S rRNA gene–based metagenomics. Results: The results showed substantial variation in sediment microbial diversity, which is correlated with the sediment chemistry and geographical locations of the sampling sites. A significant variations were also reported in pH, heavy metals, total viable bacterial count, and total organic carbon in the test sediments. Interpretation: The results demonstrate that hospital-associated contamination plays a critical role in shaping microbial communities in urban river sediments. Alterations in the microbial structure may influence key ecosystem processes, such as nutrient cycling and organic matter degradation, and pose risks to the ecosystem and public health. The findings highlight the importance of continuous monitoring and improved management of hospital wastewater discharges to protect the urban aquatic ecosystems.