Assessing metal(loid)s-Induced long-term spatiotemporal health risks in Coastal Regions, Bay of Bengal: A chemometric study.

Despite sporadic and irregular studies on heavy metal(loid)s health risks in water, fish, and soil in the coastal areas of the Bay of Bengal, no chemometric approaches have been applied to assess the human health risks comprehensively. This review aims to employ chemometric analysis to evaluate the long-term spatiotemporal health risks of metal(loid)s e.g., Fe, Mn, Zn, Cd, As, Cr, Pb, Cu, and Ni in coastal water, fish, and soils from 2003 to 2023. Across coastal parts, studies on metal(loid)s were distributed with 40% in the southeast, 28% in the south-central, and 32% in the southwest regions. The southeastern area exhibited the highest contamination levels, primarily due to elevated Zn content (156.8 to 147.2 mg/L for Mn in water, 15.3 to 13.2 mg/kg for Cu in fish, and 50.6 to 46.4 mg/kg for Ni in soil), except for a few sites in the south-central region. Health risks associated with the ingestion of Fe, As, and Cd (water), Ni, Cr, and Pb (fish), and Cd, Cr, and Pb (soil) were identified, with non-carcinogenic risks existing exclusively through this route. Moreover, As, Cr, and Ni pose cancer risks for adults and children via ingestion in the southeastern region. Overall non-carcinogenic risks emphasized a significantly higher risk for children compared to adults, with six, two-, and six-times higher health risks through ingestion of water, fish, and soils along the southeastern coast. The study offers innovative sustainable management strategies and remediation policies aimed at reducing metal(loid)s contamination in various environmental media along coastal Bangladesh.

Spatiotemporal distribution of fluoride in drinking water and associated probabilistic human health risk appraisal in the coastal region, Bangladesh.

Spatiotemporal distribution of fluoride in drinking water has been posing serious health concerns worldwide. However, in Bangladesh, to date, there is a very limited study reported the probabilistic health risks from fluoride content in drinking water. Therefore, we investigate the spatiotemporal distribution of fluoride concentration in drinking water and associated health risks in the coastal districts of Bangladesh based on randomly collected 840 groundwater samples (Dry-season = 302 and Wet-season = 538). Probabilistic health risk appraisal from fluoride was performed using the Monte-Carlo simulation and sensitivity analysis. Fluoride concentration in 11.89% (Wet-season) and 24.50% (Dry-season) of the samples exceeded the acceptable level of 1.0 mg/L, while 3.90% (Wet-season) and 7.28% (Dry-season) samples surpassed the maximum permissible limit (fluoride: 1.5 mg/L. The deficiency of fluoride content in groundwater (<0.50 mg/L) in Wet-season (60.41%) and in Dry-season (55.63%) was identified from the study area. The seasonality to the spatial change of fluoride concentration in drinking water has been explored. The mean non-carcinogenic risks e.g., hazard quotient (HQ) from the consumption of high fluoride-containing water for infants and children were mostly exceeded the threshold value 1 (HQ > 1) in both seasons. However, the risk of children and infants at the 95th percentile crossed the safe level (SL: 1) in the wet season and the risk of infants, children, teens and adults at the 95th percentile surpassed 1 in the dry season, indicating the potential adverse health effects. Apart from the high exposure, fluoride deficiency might be a severe problem in this region due to the very low concentration of fluoride (<0.50 mg/L) in drinking water. Sensitivity analyses indicate high fluoride-containing drinking water was the most contributing variables affecting the model outcome. Finally, the case-control study should be performed to examine further the health effects from the ingestion of high/low fluoride-bearing groundwater in the study area.

Evaluation of harvested rainwater quality at primary schools of southwest coastal Bangladesh.

Rainwater is a typical source of drinking water in the coastal areas of Bangladesh given the acute scarcity of drinking water. This study assessed potability of harvested rainwater of primary schools in southwest coastal Bangladesh. Water samples collected from 23 primary schools of Mongla sub-district under Bagerhat district were evaluated for indicator bacteria (total coliform (TC) and E. coli) and physico-chemical parameters (pH, electrical conductivity, turbidity, total dissolved solid, Fe, Zn, Pb, and Cd). Median concentrations of TC and E. coli in the harvested rainwater samples were respectively 3000 cfu/100 ml and 6 cfu/100 ml. However, concentrations of these indicator bacteria were lower at the consumption points which received a prior treatment. Concentration of Pb exceeded the maximum allowable limit for drinking water indicated by WHO and Bangladesh drinking water guideline value in 92% and 61% of the samples respectively, and the mean concentration was 0.08 mg/l (8 times higher than the WHO guideline value). The Pb contamination possibly occurred from the painting on roof railing and roof stair room. Therefore, consumption of harvested rainwater at primary schools may cause substantial health risk for the school-going children.