If the nitrate in surface waters is of ammonia and nitrite, it is absolutely necessary to take precautions. Such nitrates refer to water contamination. If nitrates are present with large amounts of organic substances, this can lead to great contamination.

If the nitrate concentrations in drinking water exceed 4-5 mg / l, this is a hazard to human health. High concentrations of nitrate (NO3) cause inflammation of the digestive, intestinal and urinary systems in adult humans. This concentration produces gastric acids in infants younger than six months. Nitrate poisoning level is between 3-13 mg / l in fish and other aquatic animals. Above this value, fish and other creatures are damaged.

Different methods are used for the determination of nitrate in water. One of these is the use of a High Performance Liquid Chromatography (HPLC) instrument. This method is highly sensitive and gives precise results in the separation of non-volatile or easily degradable compounds at temperature.

Nitrate content determination is carried out by HPLC method among chemical tests in authorized laboratories. In these analyzes, the standards published by domestic and foreign organizations and the methods of analysis and test criteria accepted in the world are followed and reliable and impartial service is provided in the laboratories. A few standards considered in these analyzes are:

• TS 6183 Fruit, vegetables and products - Determination of nitrite and nitrate - Molecular absorption spectrometric method
• TS EN 12014-1 Foodstuffs - Determination of nitrate and / or nitrite content - Part 1: General requirements
• TS EN 12014-2 Foodstuffs - Determination of nitrate and / or nitrite content - Part 2: Determination of nitrate content in vegetable and vegetable products by HPLC / IC method
• TS EN 12014-5 Foodstuffs - Determination of nitrate and / or nitrite content - Part 5: Enzymatic determination of nitrate content in infants and children containing vegetables