How do Nitrate and Nitrite affect the aquatic environment?
Nitrate is less toxic than the other forms of nitrogen in the aquatic environment, such as nitrite and ammonia. There is growing evidence, though, that nitrate can have a harmful impact on the development of early life stages in aquatic organisms, by reducing the oxygen-carrying capacity of the blood, or by disrupting an ability to maintain proper balance of salts. Although not usually lethal to the organism at background levels, nitrate could cause stunted growth or limit survival by causing organisms to become lethargic. Increased levels of nitrogen in the water, combined with phosphorus, can cause excessive plant and algal growth that depletes oxygen levels, possibly to lethal levels. Some algal blooms also produce toxins that can affect aquatic life or humans that consume them. What are the Nitrate and Nitrite guidelines? The Federal-Provincial-Territorial Committee on Drinking Water has established a guideline for nitrate of 45 milligrams per litre of drinking water. The guideline
