Viruses are eliminated from drinking water through the process of disinfection using chlorine . Hardness is a measure of the amount of calcium and magnesium salts in water. More calcium and magnesium lead to greater hardness. This happens because calcium and magnesium react strongly with negatively-charged chemicals like soap to form insoluble compounds. Heterotrophic Plate Count is a test performed on drinking water to determine the total number of all types of bacteria in the water.
Inorganic ions are present in all waters.
Inorganic ions are essential for human health in small quantities, but in larger quantities they can cause unpleasant taste and odor or even illness. Nitrate and nitrite can cause an illness in infants called methemoglobinemia. Fluoride is actually added to the drinking water in Glendale to promote dental health. Phosphate, sulfate, chloride, and bromide have little direct effect on health, but high concentrations of inorganic ions can give water a salty or briny taste. This is a common unit of chemical concentration.