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In Bangladesh, groundwater arsenic poisoning has become one of the biggest concern because of its use for irrigation and domestic purposes. High arsenic concentration in groundwater, soil and crops around the study area are of the greatest environmental concern and a matter of interest about human health. Groundwater, soil and crops samples collected from Bholadanga, Meherpur district, southwestern Bangladesh to measure arsenic concentration and human health risk assessment. pH value of collected groundwater samples range from 7.17 to 8.09 which exhibit lightly acidic nature.The average abundance of major cations is Ca2+ > Mg2+ > Na+> K+ and among major anions is HCO3- >Cl- > NO3-> SO42- whereas Ca2+ is the dominant cations and HCO3- dominant anions. Arsenic as well as other cations and metal like Fe, Mn, Cr, Cd, Pb, Co, Ni and so on were determined for all sorts of samples in order to assess their concentration and possible health hazard with a different statistical approaches. Principal component and cluster analyses suggested significance metal concentration in samples. At the shallow aquifer (50 – 60 m of depth) concentration of arsenic in groundwater varies from 13.1 to 292 µg/L. In groundwater approximately all the trace metals concentration are within the WHO and DOE limit except Mn, As and Fe. So groundwater of the study area are contaminated with arsenic and which is not compatible for drinking as well as irrigation purposes. Piper Tri-linear, Durov and Schoeller Semi Logarithmic diagram have been prepared based on chemical analysis of major cations and anion data and these three diagrams express that groundwater of the study area is Ca-HCO3 type, where Ca and HCO3 is the principal cations and anion, respectively. Genetically groundwater collected from the study area is ‘normal chloride water’ based on chloride, ‘normal sulfate water’ based on sulfate and ‘elevated nitrate present’ based on nitrate concentration. Based on SAR, TH, SSP, KR, MH, TH, Na%, PI and PS values, it can be concluded that the groundwater collected from the investigated area is compatible for agricultural activities. Cancer risk, daily ingestion of metal, potential hazard quotient and carcinogenic risk are used to calculate possible health hazard in the study area. Average cancer risk value is 0.0057 from drinking water suggest that people of that area are at high cancer risk according to USEPA. |
