The Effect Of Faucet Mount Water Filters On The Fluoride And Calcium Concentrations Of Tap Water

Abstract

Background: Fluoride and other minerals are present in drinking water in varying amounts either naturally or have been intentionally added. Minerals in water are important for the provision of electrolytes (calcium, magnesium, potassium) and for caries prevention (fluoride, calcium). However, the use of water filtration systems, which have become increasingly popular, can lead to a significant reduction in the concentration of some minerals in tap water. Objectives: to investigate the effect of faucet mount filters on fluoride and calcium concentrations in tap water. Materials and Methods: We investigated a convenience sample of 15 different brands of faucet mount water filters (PUR, Brita, Waterdrop, Culligan, Engdenton, DuPont, Instapure, iSpring, OEMIRY, IVO, SJ WAVE, WINGSOL, ZeroWater, AIBERLE, MIST) available in different home improvement retail stores in Indianapolis as well as on amazon.com. Water samples were collected prior to installation and after removal of the filters to determine fluoride and calcium baseline values. After mounting the filters, samples were collected at intervals when 1 L, 5 L, 10 L, 30 L, 50 L, 75 L, and 100 L of water passed through each filter for fluoride and calcium analysis. Fluoride analysis was conducted by using a fluoride ion-specific electrode (Orion #96-909-00). Calcium analysis was carried out by atomic absorption spectrometer. Results: There were significantly lower (p < 0.05) fluoride and calcium levels in PUR, Brita, and AIBERLE filters compared with unfiltered water, while Waterdrop, WINGSOL, and MIST had higher levels of fluoride and calcium. Overall, differences between filtered vs. unfiltered water were small for fluoride (up to 4-percent reduction) but larger for calcium (up to 25-percent reduction). Conclusion: The results suggest that faucet mount filters may not affect fluoride concentrations in tap water in a clinically significant manner, but some may reduce calcium concentrations significantly.