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This study examines the use of layer by layer (LbL) coated coir (CC) systems to eliminate bacterial pathogens and emerging contaminants from water. Bacterial and chemical contaminants found in river water pose risks to human health and aquatic ecosystems. The study initially compared the effectiveness of CC to uncoated coir (UC) treatment in removing bacterial pathogens. CC treatment demonstrated superior removal efficacy compared to UC treatment. For samples with a bacterial concentration of 3.6×103 CFU/mL, CC treatment achieved a removal rate exceeding 90% and viability losses of over 60% for E. coli and over 90% for S. aureus. As the number of bilayers increased, the regrowth potential of bacteria decreased, leading to mortality rates of ∼ 97% for S. aureus and 65% for E. coli respectively. Furthermore, the superiority of CC over UC in removing emerging contaminants were demonstrated. CC attained removal efficiencies of over 99% for isoniazid, 95.08% for lidocaine, 95.21% for mefenamic acid, and 87.73% for caffeine. The reproducibility of the CC system was tested and showed stable removal efficiency over multiple cycles. These findings highlight the potential of CC systems as effective eco-friendly alternatives for water purification to remove bacterial pathogens and emerging contaminants.

The degradation of recalcitrant organic pollutants by sulphate radical (SO4•−) represents one of the most recent developments in oxidation-based water treatment. In most cases, persulfate (PS) acts as a precursor of sulphate radicals. This study employed ultrasound-activated PS to generate reactive species, facilitating the degradation of bisphenol S (BPS), a well-known contaminant of emerging concern (CECs). An ultrasound with a frequency of 620 kHz and 80 W power was utilised for the degradation studies. The applied oxidation system successfully resulted in the complete degradation of BPS in both pure and real environmental water samples. Additionally, the Chemical oxygen demand (COD) was reduced to an acceptable limit in both matrices, with a reduction of 85 % in pure water and 73 % in river water. The degradation was monitored by varying chemical parameters such as pH, inorganic ions, and organics concentration. The results indicate that under specific pH conditions, the degradation efficiency followed the order of pH 3 > 4 > 7 > 11. The presence of coexisting matrices suppressed the efficiency by scavenging the reactive species. Utilizing high-resolution mass spectrometry (HRMS) analysis, this study identified seven intermediate products during identified during the degradation of BPS. Furthermore, a comprehensive mechanism has been deduced for the transformation and degradation process. All the results presented in this study underscore the applicability of the US/PS system in the removal of CECs.

An analysis on the presence of uranium in drinking water sources of five districts in Kerala, Southern India has been carried out. 830 Samples from different sources during pre and post-monsoon seasons were subjected to the analysis for uranium and 11 other water quality parameters. The concentration of uranium was found to be varying from