for Freshwater (GEMS/Water) has said that typical fresh water holds about 20 mg/litre of sulfur, and can range from 0 to 630 mg/litre in rivers, 2 to 250 mg/litre in lakes and 0 to 230 mg/litre in groundwater. Canada's rain has been found to have sulfate concentrations of 1.0 and 3.8 mg/L in 1980, found in a study by Franklin published in 1985. Western Canada in rivers ranged from 1 to 3040 mg/litre, with most concentrations below 580 mg/litre according to results from Environment Canada in 1984. Central Canada had levels that were also high in Saskatchewan, there were median levels of 368 mg/litre in drinking water from ground water supplies, and 97 mg/litre in surface water supplies, with a range of 32170 mg/litre. A study conducted in Canada found that a treatment to reduce sulfur in drinking water had actually increased. This was conducted in Ontario, which had a mean sulfur level of 12.5 mg/litre when untreated, and 22.5 mg/litre after the treatment. The Netherlands has had below 150 mg/litre concentrations of sulfur water in their underground water supplies. 65% of water treatment plants reported that the sulfur level of drinking water was below 25 mg/litre, as found in a study by Dijk-Looijaard & Fonds in 1985. The US had the Public Health Service in 1970 to measure levels of sulfate in drinking water sources in nine different geographic areas. The results concluded that all of the 106 surface water supplies that were sampled had sulfate present, as well as 645 of 658 ground water deposits that were tested. The levels of sulfur that was found ranged from less than 1 mg/litre to 770. Environment Due to sulfates being used in industrial products, they are often discharged into water supplies in the environment. This includes mines, textile mills and other industrial processes that involve using sulfates. Sulfates, such as magnesium, potassium and sodium are all highly soluble in water, which is what creates sulfur water, while other sulfates which are metal based, such as calcium and barium are less soluble. Atmospheric sulfur dioxide, also can infect surface water, and sulfur trioxide can combine with water vapour in the air, and create sulfur water rain, or what is colloquially known as acid rain. References Hydrogen sulfide in drinking water U.S. Environmental Protection Agency, Office of Drinking Water and Ground Water, Health Effects from Exposure to High Levels of Sulfate in