How do Nitrate and Nitrite affect human health?
Excessive levels of nitrate in drinking water have caused serious illness and sometimes death, especially in young infants. The harmful effect in adults and infants occurs when nitrate is converted in the body to nitrite. This interferes with the oxygen-carrying capacity of the blood, resulting in a condition called “methaemoglobinaemia”. This condition is also known as “blue baby syndrome”, because the symptoms include shortness of breath and blueness of the skin. Infants less than 3 months of age are particularly susceptible. Nitrate and nitrite have not been found to directly cause cancer in animal studies. However, nitrate, after conversion to nitrite in the body, may react with certain foods containing nitrosamines (such as cheese) to form N-nitroso compounds. Some N-nitroso compounds are potent carcinogens in animal species and could be cancer-causing in humans. How do Nitrate and Nitrite affect the aquatic environment? Nitrate is less toxic than the other forms of nitrogen in th
