Nitrate in water is permissible but not in excess,the maximum contaminant level of nitrate in water is 10 milligrams per liter.
Though the effect may not be easily reflected in adult,Nitrate occurs in water naturally as a result of plant and animal material decomposition but can also be introduced in water due to atmospere activities such as food productivity use of fertilizer and manure, disposal of domestic and industrial sewage. It can also be present household sewage.
The presence of nitrate in drinking water can result in gastric cancer and methemoglobinemia(blue baby syndrome) in children when such water is consumed.
Symptoms of blue baby syndromes are blue colouration of skin and improper circulation of oxygen even to the brain,sometimes it might leads to unconciousness.
Treatment of sewage before being released to water bodies is adviced so as to reduced dispersal of nitrogen containing compounds.
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