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Swimmer Exposure Assessment Model (SWIMODEL)

The Swimmer Exposure Assessment Model was developed by EPA as a screening tool to conduct exposure assessments of pesticides found in indoor swimming pools and spas (these include the 200+ pesticides registered for swimming pool uses, as well as those that exist in water and run-off water).

The SWIMODEL uses well-accepted screening exposure assessment equations to calculate the total worst-case exposure for swimmers expressed as a mass-based intake value (mg/event). The assessor has the option of using the default values available within the model or entering other available values. The model focuses on potential chemical intakes only and does not take into account metabolism or excretion of the chemical of concern. The SWIMODEL is being used for swimmer exposure assessments by EPA, registrants, and in academic circles.

The SWIMODEL allows the assessor to:

  • estimate exposure  via the full version option for up to six exposure routes: 
    • oral ingestion;
    • dermal absorption;
    • inhalation;
    • buccal/sublingual;
    • nasal/orbital; and 
    • aural.
  • calculate exposure via the abridged version option as a function of any one of the three major exposure routes :
    • oral ingestion; 
    • dermal absorption; or
    • inhalation.

Because the model itself can only run on computers using the Windows XP or older operating systems, we have developed a spreadsheet that includes the formulas from the model.

The spreadsheet includes assumptions from the SWIMODEL user guide (see below) and updated exposure assumptions. These updated assumptions are discussed in a presentation to Canada's Pest Management Regulatory Agency. This presentation is provided below.

We are retaining this original version of the model so anyone who has access to the appropriate operating system can use it if desired:

For questions on application installation or usage, please call Timothy Dole (dole.timothy@epa.gov) at 703-305-6450 9 a.m. to 4 p.m. ET (M-F).

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