Application of bioassays and physicochemical analysis for assessing groundwater quality of selected tube wells in a CKDu impacted area

• Published in: Groundwater for sustainable development Vol. 25; p. 101182
• Main Authors: Weerasekara, K.A.W. Shyamalee, Pathiratne, Asoka, Kithsiri, H.M. Palitha
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2024
• Subjects: Bioassay; Chronic kidney disease; Drinking water quality; Genotoxicity; Interactive toxicity; Tube well water; Interactive toxicity; Chronic kidney disease; Bioassay; Tube well water; Genotoxicity; Drinking water quality
• DOI: 10.1016/j.gsd.2024.101182
• ISSN: 2352-801X

Groundwater from tube and dug wells are primarily used for drinking purposes by rural communities inhabiting Chronic Kidney Disease of unknown aetiology (CKDu) impacted areas in Sri Lanka. Groundwater safety assessment using targeted physicochemical analysis alone is not adequate to capture interactive effects of chemical mixtures in the groundwater. This study explored for the first time combined use of physicochemical analysis and bioassays with root meristems of Allium cepa and erythrocytes of Cyprinus carpio to assess groundwater quality of selected tube wells in Medawachchiya (a CKDu impacted area), Sri Lanka covering pre-monsoon, monsoon and postmonsoon seasons. The pH, turbidity, arsenic, cadmium, lead, mercury, fluoride, chloride, nitrate and nitrite levels in the groundwater complied with Sri Lanka standards for potable drinking water in all seasons. Yet, alkalinity and total hardness levels in the groundwater exceeded national drinking water standards (nearly up to two folds) mostly in the monsoon season. Bioassays revealed genotoxic effects of the groundwater of some tube wells in pre-monsoon and monsoon seasons. Observed genotoxicity may be associated with synergistic effects of contaminants including undetected and unknown chemicals in the groundwater depending on the season. The results support the use of bioassays as complementary tools for evaluating groundwater quality of CKDu hotspots considering consumer safety. [Display omitted] •Physicochemical analysis and bioassays were used for evaluating groundwater quality.•Alkalinity and total hardness levels exceeded drinking water quality standards in most cases.•Arsenic, cadmium, lead, fluoride, and nitrate levels complied with drinking water quality standards.•Groundwater of some wells exhibited genotoxic effects depending on sampling season.•Bioassays are complementary tools for evaluating groundwater quality for drinking.