**3. Water fluoridation in Canada**

In North America, dental decay constitutes the most common chronic disease with over 96% of Canadians being affected [11]. The use of water fluoridation for the prevention of tooth decay has been used for over 60 years and is endorsed by various organizations, including Health Canada, the Canadian Public Health Association, the Canadian Dental Association, the Canadian Medical Association and the World Health Organization [3]. Approximately, 42.6% of public water supplies in Canada receive water fluoridation [16]. Over 13 million Canadian's are receiving the benefits of water fluoridation, while another 1% (270,000 people) has access to naturally fluoridated water [14]. As of 2011, the large Canadian cities without water fluoridation were Vancouver, Regina, Montreal and Calgary [4].

*Fluoride Content in Drinking Water and the Health Implications of Fluoride-Rich Water… DOI: http://dx.doi.org/10.5772/intechopen.97209*

The recommended optimal level of fluoride (0.7 mg/L) [8] is set to promote public health benefits of fluoride for preventing tooth decay while minimizing the chance for dental fluorosis. The Guidelines for Canadian Drinking Water Quality states that the maximum acceptable concentration of fluoride in public water supplies is 1.5 mg/L to protect against health risks from exposure to too much fluoride [11]. However, with fluoride levels above 1.5 mg/L over a period of time, the effects of fluorosis are observed [8].

Water fluoridation remains a contentious issue in Canada and many communities chose to fluoridate their water supply [3]. As of 2007, 45.1% of the Canadian population had access to fluoridated water supplies [9, 11]. The main argument for and against fluoridation have changed very little over the years, with supporters (including the World Health Organization and Health Canada) citing evidence that shows fluoridation as a safe and effective method of caries prevention, while detractors cite high costs and potential health risks [17].
