What Causes Ammonia in Pool Water?

Both public and private swimming pools require ongoing maintenance in order to ensure that the water is safe for humans to swim in. Regular testing of the water as well as proper chlorination will help reduce the risk of unsafe levels of pollutants negatively affecting swimmers. One of the most common unwanted pool pollutants is ammonia, which may be brought to the water by humans or outside environmental conditions.

Elements excreted by swimmers, such as sweat and urine, are largely comprised of three main elements: water, urea and ammonia. As the components of urine and sweat are broken down by the pool water and the chemicals that are present in the water, ammonia is separated out and becomes recognizable in water tests. The ammonia found in urine alone is not harmful to swimmers; however, when combined with chlorine, it may cause symptoms such as eye irritation in some swimmers.

Pools that are located near fields or gardens that have been fertilized may show high levels of ammonia caused by fertilizer particles being carried to the water by wind and rain runoff. Many fertilizers have high levels of ammonia in their make-up, which can be hazardous to swimmers. Placing a sealed cover over the pool when it is not in use will help reduce the risk of fertilizer particles entering the pool water.

Environmental factors, such as decaying leaves and plant materials in the water, may cause the presence of ammonia in a pool that has not been properly treated with chlorination chemicals. As organic materials break down in the water, they may produce ammonia that will become more and more prevalent as leaves are allowed to build up in the pool. Regularly cleaning leaves and plant debris out of the pool water will help reduce the risk of ammonia from this source.

Certain products, such as some suntan lotions or contaminants carried on swimmers' bathing suits, may also contain ammonia. As swimmers enter the pool and lotions break down, or clothing is soaked with chlorinated water, ammonia from the imported products will begin to break down and contaminate the pool water. Asking swimmers to rinse off in a pool shower before entering the water may reduce ammonia contamination caused by products imported by swimmers.