Haloacetic acids in swimming pools: swimmer and worker exposure.

For the first time, the exposure of swimmers and workers to haloacetic acids (HAAs) in indoor and outdoor pools was evaluated through the analysis of urine samples. The subjects of this study, 49 volunteers, were male and female workers as well as swimmers (adults and children) who regularly attended an indoor pool (January-June) and an outdoor one (July and August). The results showed that HAAs appeared 20-30 min after exposure and were eliminated within 3 h. After 2 h exposure, urine samples taken from workers contained dichloroacetic (DCAA) and trichloroacetic (TCAA) acids at 300 and ~120 ng/L levels since HAAs were aerosolized in the indoor ambient, whereas only DCAA was found in some workers' urine samples from the outdoor pool but at ~50 ng/L levels, despite the fact that the outdoor pools generally had somewhat higher levels of HAAs than the indoor pools. After 1 h swimming TCAA, DCAA and MCAA were present at concentrations of ~4400, ~2300, and ~560 ng/L, respectively, in the swimmers' urine in the indoor pool; similar results were obtained from the swimmers in the outdoor pool due to accidental ingestion. Finally, exposure estimates indicate that ingestion is the major route of exposure (94%), followed by inhalation (5%) and dermal contribution (1%).