Analysis of trihalomethanes in water and air from indoor swimming pools using HS-SPME/GC/ECD

Abstract

Headspace solid phase microextraction (HS-SPME) with further quantification by gas chromatography and electron capture detector (GC/ECD) was used to analyze trihalomethanes (THMs) in water and air from indoor swimming pools (ISPs). High correlation coefficients were obtained for the calibration lines in water with detection limits of 0.2 μg/L for trichloromethane (TCM) and bromodichloromethane (BDCM), 0.1 μg/L for dibromochloromethane (DBCM) and 0.5 μg/L for tribromomethane (TBM). Coefficients of variation values were 5–10% for repeatability and 15–25% for reproducibility. In air analysis, high correlation coefficients were also obtained for the calibration lines with detection limits of 2.5 μg/m3 for TCM and BDCM and 1.25 μg/m3 for DBCM and TBM. Repeatability and reproducibility coefficients of variation were the same as in water analysis. Analytical results from a survey in four Portuguese ISPs showed that the mean concentration of total trihalomethanes (TTHMs) in water ranged from 22±2 to 577±58 μg/L. In the lack of European specific regulation for THMs in water from ISPs and taking into consideration that ingestion is a form of exposure, TTHMs’ values were compared with European drinking water maximum contamination level (100 μg/L, Directive 98/83/CE). From the reported TTHMs mean concentration values in ISPs’ water, 40% exceeded that value. TTHMs values determined in the air (T = 30°C) ranged from 98±10 to 1225±123 μg/m3 and from 51±5 μg/m3to 519±52 μg/m3at 5 and 150 cm above the water surface, respectively. As expected, swimmers are more exposed to high concentrations of THMs than lifeguards. As there is no European specific regulation for THMs in ISPs’ air, the highest TCM values were compared with maximum values reported in the literature for ISPs (1630 μg/m3) and with the inhalation exposure limit (10,000 μg/m3) established for TCM by European occupational legislation (Directive 2000/39/CE).