Читать книгу Groundwater Geochemistry - Группа авторов - Страница 46

A high level of fluoride in groundwater has been reported from the USA, mainly in facility wells of industries in Pennsylvania, having 3.2 and 6.5 mg/L of fluoride; Lakeland, Southern California, having 3.6–5.3 mg/L of fluoride; and deep aquifers present in the western US comprising 5–15 mg/L of fluoride (Cohen and Conrad 1998). The presence of fluorosis has also been reported in different states of the USA, such as Oklahoma, Nevada, South Carolina, North Dakota, Texas, Oregon, California, Utah, Colorado, New Mexico, Virginia, and North Carolina. Five million people in Mexico (around 6% of the total population of the country) have been affected by pollution of fluoride in groundwater. In Canada, there are several communities whose natural drinking water sources contain higher levels of fluoride (as high as 4.3 mg/L). Industrial discharges are the main reason behind fluoride contamination reported in the USA and Canada (Rose and Marier 1977). A few parts of Argentina contain fluoride concentrations of about 5 mg/L in groundwater (Kruse and Ainchil 2003).