The fluoride contamination in groundwater and assessment of fluoride exposure for residents in Tay Son, Binh Dinh

Abstract

This study focuses on determining the concentration of fluoride in groundwater and estimating the fluoride exposure through drinking water of three different age-groups for residents in Tay Son district, Binh Dinh province. A total of 50 well-water samples were collected and 220 people were surveyed by questionnaire from 50 households at 3 communes: Tay Phu, Binh Tuong, Tay Giang of Tay Son district. Results of this study showed that fluoride concentrations in well-water varied from 0.31 mg/L to 7.69 mg/L (mean 2.66 mg/L, SD: 2.18 mg/L) with 70% of the well-water samples above the maximum permissible limit of 1.5 mg/L (QCVN 09:2008/BTNMT). Groundwater in the studied area is seriously contaminated with fluoride. Exposure of fluoride among three age-groups was calculated according to the guidance of United States Environmental Protection Agency (US EPA). The maximum estimated exposure doses of 0.721 mg/kg/day in the age-group of below 6 year, 0.530 mg/kg/day in the age-group between 6 and 12 years and 0.320 mg/kg/day in the age-group above 12 year exceed the LOAEL value of 0.1 mg/kg/day (WHO, 1984). A health risk due to fluorosis to the people in Tay Son district has become an evidence.