Naturally Occuring Constituents
Nitrate Excessive levels of nitrate in drinking water have caused serious illness and sometimes death in infants under 6 months of age. The serious illness in infants is due to the conversion of nitrate to nitrite by the body, which can interfere with the oxygen-carrying capacity of the child's blood. This can be an acute condition in which health deteriorates rapidly over a period of days. EPA has set the drinking water standard for nitrate at 10 mg/l to protect against the risk of these and other adverse health effects.	Copper is a health concern at certain levels. Copper contaminating drinking water occurs as the result of the corrosion of copper pipes that remain in contact with water for a prolonged period of time. Copper is an essential nutrient, but at high doses it has been shown to cause stomach and intestinal distress, liver and kidney damage, and anemia. Persons with Wilson's disease may be at higher health risk than the general public. To protect against adverse health effects, EPA requires that 90% of tap water samples test lower than 1.3 mg/l copper.
Barium is a health concern at certain levels of exposure. This inorganic chemical occurs naturally in some aquifers that serve as sources of ground water. It gets into drinking water after dissolving from naturally occurring minerals in the ground. this chemical may damage the heart and cardiovascular system when exposed at high levels throughout a lifetime. EPA has set the drinking water standard for barium at 2 mg/l to protect against the risk of these adverse health effects.	Coliform is a naturally occurring bacterial group found in the environment. Most types are not harmful. The presences of coliform bacteria is considered an indicator that disease causing organisms may be present. E. Coli is one species from this group that is harmful and therefore it is monitored closely. In 1999, we tested 480 samples for Total Coliform and E. Coli. All samples were negative, meaning these bacteria were not present. EPA's maximum contaminant level rule requires that less than 5% of samples tested can be positive for coliform bacteria and certain measures must be taken when a positive sample is found.
Sodium is a naturally occurring mineral which is found in most all of Utah's water sources. While sodium is not regulated as a contaminant in drinking water, it may have an effect on the consumer's health. In general, the sodium contributed to an individual's diet from drinking water is a small part of overall dietary intake. The American Heart Association's recommended standard for daily sodium intake is 3,000 milligrams. Persons on severely restricted sodium diets may want to consult their health professional regarding sodium levels in water.	Iron Clothes laundered in water with high iron content can become stained. The iron in the water, if in excessive amounts, can spontaneously react with manganese and dissolved oxygen, promoting the growth of a group of microorganisms known as iron bacteria which result in dirty water, foul tastes and unpleasant odors.
Fluoride A level of 0.8 - 1.2 mg/l is recommended by the state to aid in keeping teeth healthy, especially in children. The City of St. George does not add fluoride to any of its water sources. The natural occurring level of fluoride in all our sources is less than .2 mg/l - which is below the recommended level for healthy teeth and bones.	TDS Mineral content is measured by the amount of total dissolved solids, or TDS, in the water. The federal secondary drinking water standard for TDS is 500 parts per million. There is no health basis for this level, buy many people can detect a salty taste in the water when TDS is above 500 parts per million.
pH pH is an expression of the intensity of the basic or acidic condition of a liquid. pH may range from 0 to 14, with 0 being most acidic, 14 the most basic and 7 neutral. The Health Department recommends a pH level of 7-8.	Lead EPA's national drinking water regulation requires all public water systems to optimize corrosion control to minimize lead contamination resulting from corrosion of plumbing materials. To protect against adverse health effects EPA requires that 90% of tap water samples have lead concentrations below .015 mg/l.
Get more information about contaminants in drinking water from the Environmental Protection Agency's Safe Drinking Water Hot Line (800-426-4791), or visit their web site at http://www.epa.gov/safewater .