Quality assessment of freshwaters from a coastal city of southern Bangladesh: Irrigation feasibility and preliminary health risks appraisal

Abstract The present study was conducted for the first time to appraise the water quality, irrigation feasibility, and human health risk of surface water in heavy industrial and urban establishments from a coastal city of Bangladesh. Surface water samples were collected from the hilly terrain comprised of Plio-Pleistocene to Miocene-sediments throughout the study area. The ranges of pH were 5.35 to 7.58, EC values were 42.3 to 2440 µS cm−1, and turbidity were 2.53 to 1570 NTU, respectively. The overall physicochemical condition of water samples revealed that the water was unsuitable and also unsafe for domestic use. A bias-free systematic sampling and analyzed parameters invoke that surface water quality is deteriorated by Cr (52.2), Mn (532), Fe (4797), Mg (31445), K (29213), Co (69.0), Ni (39.5), and Pb (22.4 µg L−1) contamination and make the surface water unsuitable for drinking, cooking, fisheries, and other purposes. Anthropogenic activities (e.g., domestic, industrial, agricultural, etc.) intensified by climate change-induced sea-level rise are mainly responsible for the source apportionment of metal pollution in the study region. However, the surface waters of the studied sites are allowed to use for irrigations, except for Karnaphuli river due to high alkali hazards. Furthermore, the existence of toxic metal-induced non-carcinogenic and carcinogenic risks does not allow inhabitants to use this water for household works.