Groundwater quality assessment and health issues in coastal zone of Bangladesh

Abstract

The purpose of this study was to assess the water quality index (WQI), heavy metal evaluation index (HEI), heavy metal pollution index (HPI) and hazard index (HI), and the associated environmental/human health issues of the south-western coastal Bangladesh (SWCB). Rajoir, Gangarampur and Ganapatipur villages were purposively selected from shoreline (X), interim (Y) and inland (Z) coast of SWCB. 40 ground water samples were collected from 20 sampling sites; and 18 variables, such as, temperature, pH, electrical conductivity (EC), dissolved solids (TDS), suspended solids, dissolve oxygen, total hardness, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb ions were tested to perform the study. In addition, four focus group discussions were also conducted to understand the current health scenarios. The strong positive correlation between EC:Cu (r = 0.856), TDS:Mn (r = 0.664), TDS:Cu (r = 0.880), K:Mn (0.736) and Mn:Cu (r = 0.601) suggested the homogeneous sources of origin or/and anthropogenic activities or pollutant movement of these variables. The changing patterns of mean WQI, HEI, HPI, HIinfant, HIchild and HIadult of the study area were X(79.19)<Y(91.54)<Z(102.31); X(4.96)>Y(4.93)>Z(3.79); X(78.66)<Y(91.72)<Z(102.11); X(0.8)<Y(1.11)<Z(1.32); X(1.77)<Y(2.46) <Z(2.93); X(1.15)<Y(1.60)<Z(1.91), respectively. Therefore, it is argued that 66.67, 50 and 50% water samples from X, Y and Z coast grouped into category ‘very poor’, ‘excellent’ and ‘unfit’ based on WQI. In addition, 50, 40 and 50% water samples from X, Y and Z coast grouped into category ‘slightly affected’, ‘seriously affected’ and ‘moderately affected’ depending upon HEI. 100, 70 and 50% water samples from these villages were within the HPI (<100). Finally, the degree of pollution was increased from shoreline to inland areas based on HI results for infant, child and adult, respectively. Lastly, it confirmed that human health should be deteriorated for the long-term consumption of polluted/contaminated water and negatively impacted on biodiversity loss of the study area.