Monitoring of Fluoride Content in Drinking Water by Ion Chromatography: A Case Study in the Suzhou Urban Area, China

Background: Both deficient and excessive intake of fluoride can lead to adverse health problems. Objective: The aim of this study is to investigate the fluoride content in three types of drinking water in Suzhou urban area. Method: Ion chromatography was employed to conduct the validation of analysis of fluoride ion in water and the method was applied to analyze the concentration of fluoride in 22 drinking water samples, including tap water, purified water, and commercially available bottled water, collected from five municipal districts of Suzhou urban area. Results: The method was validated in the range of 0.05-2.00mg/L with good repeatability and accuracy. Results of water analysis indicated that fluoride content in tap water ranged from 0.267 to 0.336mg/L (average 0.304mg/L), and the levels of fluoride in purified water and bottled water were 0.068-0.317mg/L (average 0.134mg/L) and 0-0.120mg/L (average 0.080mg/L), respectively. Conclusions: The amount of fluoride in all samples analyzed were lower than the limit set for fluoride in drinking water according to the China standard (1.0mg/L). Low fluoride exposure for the population in the studied area was observed, and the replacement of tap water with purified and bottled water could further aggravate the deficiency of fluoride intake for local residents. Highlights: The present study is the first to characterize the fluoride content in these three types of drinking water in Suzhou urban area by ion chromatography.