Key Points

 a colourless gas with a strong odour similar to urine

 it readily dissolves in water to form a corrosive solution

 an important industrial chemical, used to make fertilisers, plastics, synthetic fibres, dyes, explosives and pharmaceuticals

 it is produced naturally in the environment and the human body

 agriculture also contributes to ammonia levels in the environment

 exposure to ammonia may occur at work, from household products that contain it, or from low levels in foods

 the health effects of ammonia are usually immediate and long term effects would not be expected after exposure to small amounts

 inhaling high levels of ammonia may cause burns and swelling in the airways, lung damage and can be fatal

 strong ammonia solutions or gases may cause burns to the skin and serious eye damage