Appraising spatial variations of As, Fe, Mn and NO3 contaminations associated health risks of drinking water from Surma basin, Bangladesh

This study aims to appraise the spatial variations and pathways of groundwater contaminations and associated health risks in the Surma basin, Bangladesh using geostatistics, Fuzzy GIS technique and health risk modelbased on ninety groundwater samples. The results show that the mean concentrations of As, Fe, Mn and NO3 are below the Bangladesh water quality standard, whereas As, Fe and Mn concentrations exceed World Health Organization guideline values in several sampling sites. The compositional study identifies weathering of source rocks, reductive dissolution of Fe and Mn-oxyhydroxide minerals and various anthropogenic inputs as the key sources of groundwater contamination. The kriged maps show the elevated risks of Fe, Mn and NO3 concentrations from the south to northern parts and As concentration from…