TEHRAN, Jan.24 (Mehr News Agency) -- Tehran water supply has the highest level of nitrate in the country, director of Tehran's Department of Environment (DOE) said here on Thursday.

"Nitrate level in the capital's water supply has exceeded the drinking water quality standards," Mohammad-Baqer Saduq said, stressing that now is the time to put fears about nitrate levels in water into true perspective.

The standard for nitrate in drinking water is 10 milligrams per liter (mg/l) nitrate-nitrogen (NO3 -N) or 45 milligrams nitrate (NO3).

Karaj dam north of Tehran

Water testing for nitrate indicated that after Tehran, water supplies of the provinces of Mashad, and Arak have respectively the highest levels of nitrate, Saduq added.

Nitrate (NO3) is the primary source of nitrogen (N) for plants and they cannot live without this nutrient. Nitrate is an inorganic compound that occurs under a variety of conditions in the environment, both naturally and synthetically. Nitrate does not normally cause health problems unless it is reduced to nitrite (NO2).

High levels of nitrate in household water supplies are of grave concern, Saduq said, referring to some of health problems caused by nitrate, including methaemoglobinaemia -- commonly referred to as "blue baby" disease, marked by a reduction in the oxygen-carrying capacity of blood -- digestive problems, and stomach cancer.

... Payvand News - 01/24/09 ... --