School of Environmental Studies, Jadavpur University, Kolkata 700032, India.
Department of Mining Engineering, Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India.
J Hazard Mater. 2024 Mar 5;465:133216. doi: 10.1016/j.jhazmat.2023.133216. Epub 2023 Dec 12.
The present study depicts the true failed scenario of the arsenic (As) removal units (ARU) in West Bengal by evaluating their treated water quality. Annual As removal efficiency of the 12 studied ARUs range between 35.2% and 82.6%. A comprehensive physico-chemical parameters and trace elements analysis find almost 25% and 16.7% of treated drinking water samples with poor water quality index (WQI) and high heavy metal evaluation index (HEI), respectively. The pond-based water treatment plant maintains the production of continuous As-safe water with a range between 60.2% and 66.7% due to its high Fe/As ratio. It's a discontent concluding the treated drinking water of the groundwater based-ARUs were observed with sufficient As mediated cancer risk (3 ×10). The non-cancer risk (HQ) of As is safe for the surface water treatment plant (0.38), whereas it is threatening for the groundwater based-ARUs (7.44). However, the drinking water samples are safe in view of HQ from the other trace elements like Hg, Al, Cd, Cr, Pb, F and NO. Small scale ARU could be a feasible mitigation strategy in reducing the As menace in the long run if the plants are maintained correctly. Nevertheless, surface treated water is the most sustainable solution as withdrawal of groundwater for drinking purpose is not a viable practice.
本研究通过评估其处理后水质，描绘了西孟加拉邦砷（As）去除装置（ARU）的真实失败情况。12 个研究中的 ARU 的年 As 去除效率在 35.2%至 82.6%之间。全面的物理化学参数和微量元素分析发现，近 25%和 16.7%的处理饮用水样本的水质指数（WQI）和重金属评估指数（HEI）较差。由于其高 Fe/As 比，基于池塘的水处理厂能够生产持续的 As 安全水，范围在 60.2%至 66.7%之间。由于地下水资源的 ARU 处理后的饮用水中含有足够的砷介导的癌症风险（3×10），因此这是一个令人不满的结论。非癌症风险（HQ）对于地表水水处理厂（0.38）是安全的，而对于地下水基 ARU（7.44）则是威胁。然而，从其他微量元素如汞、铝、镉、铬、铅、氟和硝酸盐的 HQ 来看，饮用水样本是安全的。如果正确维护，小规模的 ARU 可能是长期减少砷威胁的可行缓解策略。然而，由于饮用水不能从地下水中提取，因此表面处理水是最可持续的解决方案。
