Possible contaminants in swimming pools

Environmental Sources

Affecting primarily outdoor swimming pools, environmental contaminants include:

  • windblown dirt and debris
  • incoming water from unsanitary sources
  • rain containing microscopic algae spores
  • droppings from birds possibly harbouring disease-causing viruses

Indoor pools are less susceptible to environmental contaminants.

Contaminants introduced by swimmers

Sources include micro-organisms and body oils from infected swimmers:

  • sweat
  • cosmetics
  • suntan lotion
  • urine
  • saliva
  • faecal matter.

In addition, the interaction of disinfectants and contaminants can produce a mixture of chloramines and other by-products.

Pathogenic contaminants are the greatest concern in swimming pools as they have been associated with numerous recreational water illnesses (RWIs).

Public health pathogens can be present in swimming pools as:

  • viruses
  • bacteria
  • protozoa
  • fungi

Diarrhoea is the most commonly reported illness associated with pathogenic contaminants, while other diseases associated with untreated pools are Cryptosporidiosis are and Giardiasis.

Other illnesses commonly occurring in poorly maintained swimming pools include otitis externa, commonly called swimmers ear, skin rashes and respiratory infections.