Ammonia, NH3, is a colourless gas, with a distinct odour composed of nitrogen and hydrogen atoms. It occurs naturally from the decaying of organic matter, but it is also produced in large quantities by humans in the production of fertilisers, plastics, pharmaceuticals and petrochemicals.
Human exposure to ammonia often occurs through inhalation of the gas or vapours. Although at low concentrations, ammonia is generally harmless, at high concentrations ammonia will cause damage to vegetation and is an irritant to the eyes and nose.
Ammonia is present in a variety of applications, read below to find out why it is necessary to monitor ammonia.
Ammonia needs to be monitored in drinking water to safeguard human health. It can be present in drinking water after disinfection using monochloramine or as a result of leaching from materials used in water pipework construction.
Chlorine is known to react with ammonia. If drinking water contains more than more than 0.2 mg/L of ammonia, and chlorine is used as a disinfectant the taste and odour of the water can be affected. This can also make the chlorine less effective, which can impact cost efficiency and the safety of the water.
When natural materials are broken down by bacteria, ammonia can be formed as a by-product. Increased levels of ammonia are caused by iron rich soil, human deposits, being near a forest, fertilizer and faecal contamination of the water.
Ammonia needs to be monitored in surface and ground water because high levels of ammonia in water can be an indicator of faecal contamination or fertiliser run-off into the water.
Ammonia can reach high levels in wastewater due to bacterial action. It is important to monitor ammonia in wastewater as once the effluent is released high levels of ammonia can be detrimental to aquatic life.
Removal of ammonia from wastewater is carried out using the Nitrification Process to convert ammonia to nitrate. Water then goes through a denitrification process to reduce the water’s nitrate levels to safe levels.
Ammonia is incredibly toxic to aquatic life, so ammonia monitoring is essential for aquaculture applications. Ammonia is a waste product of aquatic life which must be closely monitored due to its poisonous effects, especially at a lower pH. In a well-established aquarium, ammonia will rapidly be converted to nitrite and eventually nitrate. Most aquariums aim to have zero ammonia present.
For more information about ammonia and other key test parameters in aquaculture take a look at our case study on Water Testing at London Zoo.
Fertilizer addition is a major source of ammonia in soil, but the natural nitrogen-fixing bacteria found in soil will draw nitrogen from air and convert to ammonia as part of the nitrogen cycle. Ammonia is also frequently present in soil as a result of urea dosing. Hydroponic nutrient solutions introduce nitrogen as an ammonia salt.
Ammonia levels should be monitored as ammonia is a source of nitrogen for plants, and plants require nitrogen for growth.
The Compact Ammonia Duo uses both Nessler and Indophenol method analysis to measure ammonia and ammonium in drinking water, wastewater or environmental samples. This is also available as part of a Turbidity and Ammonia Combined Kit, ideally suited to wastewater professionals.
Denitrification is the conversion of nitrate and nitrite to nitrogen as part of the nitrogen cycle.
Nitrification is the conversion of ammonia to nitrate via the intermediate nitrite as part of the nitrogen cycle.