All drinking water should be filtered to remove toxins
The environmental impact of excess bottled water consumption is well stated, however, the potential health impacts of either tap or bottled water consumption have not been considered.
Toxins in tap water include arsenic, aluminium, fluoride, trace amounts of discarded medications, chlorine and chlorine disinfection by-products. Arsenic is carcinogenic and the US Environmental Protection Agency (EPA) reduced the maximum level of arsenic permitted in drinking water from 50 to 10 µg/L. The US Natural Resources Defense Council estimates that as many as 56 million Americans living in 25 states drink water with arsenic at unsafe levels (http://www.nrdc.org/water/drinking/qarsenic.asp). Aluminium has been linked to Alzheimer´s disease and several other problems (1). Fluoride is a neurotoxin (2). Leaching of water through landfills which contain discarded medications results in their presence in drinking water (3), the effects of which remain undetermined. Chlorine and chlorine disinfection by-products are also present in tap water, both of which are toxic to mammalian physiology (4).
However, bottled water is not necessarily better, as much of it is actually bottled tap water. In addition, drinking any water from a plastic bottle is hazardous due to leaching of bisphenol A (BPA) which is a hormone disruptor (estrogen mimic) which has been associated with multiple health problems, including early puberty, risk of obesity and various cancers (5). There are additional problems with distilled, alkaline and ´vitamin´ waters.
To preserve health and prevent disease, all drinking water should be filtered. The best type of filter is a granular-activated carbon block filter (as recommended by the EPA), which removes most harmful chemicals and metals. Filtered water is best carried in bottles made of steel or glass, but not plastic.
1. Yegambaram M, Manivannan B, Beach TG, Halden RU. Role of environmental contaminants in the etiology of Alzheimer's disease: a review. Curr Alzheimer Res. 2015;12(2):116-46.
2. Choi AL, Sun G, Zhang Y, Grandjean P. Developmental fluoride neurotoxicity: a systematic review and meta-analysis. Environ Health Perspect. 2012 Oct;120(10):1362-8.
4. Nieuwenhuijsen MJ, Toledano MB, Elliott P. Uptake of chlorination disinfection by-products; a review and a discussion of its implications for exposure assessment in epidemiological studies. J Expo Anal Environ Epidemiol. 2000 Nov-Dec;10(6 Pt 1):586-99.
5. Gao H, Yang BJ, Li N, Feng LM, Shi XY, Zhao WH, Liu SJ. Bisphenol A and hormone-associated cancers: current progress and perspectives. Medicine (Baltimore). 2015 Jan;94(1):e211.
Competing interests: No competing interests