Appraisal of groundwater quality and human health risk for water security and health safety assurance in southwest coastal zone of Bangladesh

The higher salinity and other physico-chemical elements along with trace metals have become a major risk in the coastal areas of Bangladesh. This study investigated the quality of physico-chemical parameters and some trace elements along with the appraisal of potential human health risk in groundwater. Groundwater samples were collected from 31 pre-selected tube-wells of the study area and analyzed for pH, EC, TDS, major cations, anions and some heavy metals. Almost all the parameters including heavy metals in groundwater were found much higher than the standard permissible limits. Increased major cations and anions in groundwater samples represent the presence of seawater in coastal aquifers and increased heavy metals indicate the presence of anthropogenic actions. Principal component analysis (PCA) and cluster analysis were also performed to establish the pollution source and controlling factors, which indicated the groundwater mainly influenced by geogenic evolutions along with some anthropogenic sources. Chronic health risks of cations and anions exposure via oral route were identified by calculating the hazard quotient (HQ) and hazard index (HI) for both adults and children. Results reveal that non-carcinogenic health risk may occur moderately to adults and highly to children. Spatial distribution analysis reveals that study area possesses a high cancer risk of arsenic (As) for both adult and children due to consumption of contaminated groundwater for long time. Finally, this research clearly represented the groundwater quality challenges by taking into consideration the multi-hazards in the study area that will help taking initiative for the development of sustainable treatment policies to remove the pollution from groundwater in future.