Swimming pools and recreational water facilities fill with and continuously replenish water from municipal or well supplies. PFAS in fill water introduces contamination to swimming pools, and the health implications of PFAS exposure through swimming — primarily dermal contact and incidental ingestion — merit understanding even though this route contributes less to total body burden than drinking water ingestion.
PFAS in Pool Water
Pool water PFAS concentrations primarily reflect the source water supply, as standard pool disinfection (chlorine, bromine, UV, or ozone) does not remove PFAS. Pool water evaporation concentrates PFAS over time as water is lost but PFAS remains — a similar effect to cooking water concentration. Regular water addition to maintain pool levels introduces additional PFAS, while evaporation losses leave an increasingly concentrated pool environment for persistent contamination sources.
Exposure Assessment for Swimming
Dermal PFAS absorption during swimming is generally limited for most PFAS compounds due to their low dermal permeability. Incidental ingestion — swallowing pool water — is the more significant exposure route for swimmers, particularly children who swallow more water per body weight. At typical pool PFAS concentrations reflecting municipal supply levels, swimming exposure is generally small relative to drinking water exposure, but high-frequency swimmers with contaminated pool water accumulate additional exposure.
Treatment Options
Point-of-entry filtration on pool fill water using carbon or RO before water enters the pool reduces pool water PFAS concentrations proportionally to the filter’s removal efficiency. For public pools or facilities concerned about comprehensive environmental management, this represents a relatively low-cost intervention given the typically modest volume of makeup water required relative to total pool volume.