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Updated: Jan 30, 2026

Sampling and Identification of Microplastics in Groundwater
Published on: November 7, 2025
Groundwater fluoride in Sri Lanka: opportunities to mitigate the risk at maximum contaminant level
N Ranasinghe1, E Kruger, R Chandrajith
1International Research Collaborative – Oral Health And Equity, School of Human Sciences, The University of Western Australia, Australia. nirosandi1976@gmail.com
Introduction:
High groundwater fluoride (F) is one of the major environmental hazards in the dry zone of Sri Lanka. The prolonged exposure to F at maximum contaminant levels can give rise to lifelong debility and disability among its inhabitants.
Objectives:
This study investigated the F contamination in groundwater resources in Sri Lanka above recommended Maximum Contaminant Levels (MCL) and possibilities to mitigate the health risk.
Methods:
Groundwater samples (6107) were randomly collected from different geographic areas of the country, and categorised as hazardous, if it exceeded the maximum contaminant level of 4 mg/L (the level at which bone health is compromised). The minimum distances from a hazardous to a relatively safe F groundwater source (below 1.0 mg/L and 1.5 mg/L) were determined using geospatial analysis. Results: Only 2.3% (142) of the total sample was found to be hazardous to skeletal health. Optimal F sources were identified in close proximity to highly contaminated sources (>4.0 mg/L), some even within a walking distance of 500 metres.
Conclusions:
The identification and elimination of maximally contaminated sources, possibly by dilution with widely available low F sources in close proximity, would be a more feasible and cost effective approach to ensure long term public health benefits.
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