Tehran’s water is not contaminated but its quality has declined. In the past, 30% of the water supply was from wells and 70% from dams; at present 45% is well water supply and 55% from dams; however, it hasn’t exceeded the permissible limits from both sources, Salamat News quoted Seyyed Hassan Hashemi, Tehran Province governor as saying.
Wells are more vulnerable to nitrate contamination than dams. Nitrate contamination can occur particularly in shallow wells, dug wells with casing which is not watertight, and wells with damaged, leaking casing or fittings.
Too much nitrate in drinking water poses a risk to infants less than six months of age. If an infant is fed formula made with water that is high in nitrate, a condition called “blue baby syndrome” can develop. Bacteria which are present in an infant’s stomach can convert nitrate to nitrite, a chemical which can interfere with the ability of the infant’s blood to carry oxygen.
