Integrated application of pollution indices and multivariate statistics for assessing groundwater contamination by potentially toxic elements in the southern coastal region of Bangladesh
Year: 2026
Type: article
Abstract: ABSTRACT Graphical abstract illustrating groundwater potentially toxic element (PTE) risk in coastal Bangladesh, focusing on Noakhali District. A total 27 groundwater samples were assessed for both wet and dry seasons. Key findings showing Fe dominance in both seasons and elevated Al and Mn during the dry season, and spatial hotspots of contamination in central and southern areas. It highlights human health risks primarily through oral ingestion, with children identified as the most vulnerable group, and dermal exposure remains low. The diagram also indicates likely contamination sources including geogenic weathering, agricultural runoff, and saline intrusion, along with implications for monitoring and safe water management. Groundwater contamination poses major environmental and health risks in the coastal districts of Bangladesh, where communities rely on aquifers for drinking and irrigation. This study evaluated groundwater quality in Noakhali through 27 samples from wet and dry seasons, analyzing seven potentially toxic elements (Al, As, Cu, Mn, Cr, B, Fe). Fe dominated contamination in both seasons, frequently exceeding WHO and national guidelines. Al and Mn surpassed safe thresholds during the dry season; in contrast, As and Cr mostly remained within permissible limits. Spatial hotspots were identified in central and southern zones. Pollution indices (MPI, NPI, PoS) indicated moderate to severe contamination, mainly driven by Fe and Al, whereas MEI and Cd suggested overall safety with localized concerns. Hazard Quotient (HQ) values remained below unity, indicating no significant individual risk; however, Hazard Index (HI) exceeded safe limit in 22.2% of dry-season samples, particularly affecting children, suggesting combined effects of multiple metals. Oral ingestion was the dominant exposure pathway, while dermal risks were negligible. Multivariate analyses (PCA, HCA) attributed contamination mainly to geogenic processes like mineral-weathering and water-rock interactions, with minor anthropogenic inputs. These findings highlight the need for continuous monitoring and targeted mitigation strategies to protect vulnerable populations in coastal Bangladesh.
Source: Journal of Water and Health
DOI: 10.2166/wh.2026.033
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7168024654