The Development and Validation of a Diffusive Sample with a Variable Sampling Rate for Long‐term Sampling of VOCs

PS 403‐17 Sampling and Analysis of Airborne Trichloramine in Indoor Swimming Pools T. Chu, S. Tsai, National Taiwan University, Taipei, Taiwan; S. Cheng, Council of Labor Affairs, Executive Yuan, Taipei, Taiwan. Objective: In swimming pools, visitors can contribute various kinds of organic nitrogen, such as sweat, or skin particles, which would react with chlorine to form trichloramine. It has been observed that the exposures of highly‐volatile trichloramine might cause acute and chronic health effects in both children and adults. In this research, the concentrations of trichloramine in indoor swimming pools in Taipei were determined, while the respiratory irritation symptoms among pool workers were also investigated. Methods: The air sampler for trichloramine was composed with a 6 mL cartridge tube and a 37mm cassette. Silica gel coated with sulfamic acid in the cartridge tube was functioned to trap interferences, including chlorine, hypochlorite, monochloramine and dichloramine. To measure trichloramine, two quartz fiber filters coated with diarsenic trioxide and sodium carbonate were placed in the cassette. During sampling, the air flow rate was 1L/min. After sampling, the silica gel was desorbed by sulfamic acid, acetate buffer and potassium iodide, and the resulted total chlorine concentration was determined by the pocket colorimeter. Besides, the quartz filters were desorbed by twice‐distilled water, and the chloride ion reduced from trichloramine was analyzed by ion chromatography. Pool workers were asked to complete a questionnaire concerning workplace information as well as work‐related symptoms. Results: The concentrations of trichloramine found in this study ranged from 0.019~0.06 mg/m3, while the concentration of total chlorine in air ranged from .005~0.18mg/m3. Irritation symptoms were observed among pool workers with the prevalence of 21% for eye irritation, 16 % for cough, and 26% for sore throat. Conclusions: Compared with other published data, the concentrations of trichloramine in this study were relatively low. However, work‐related irritation symptoms still occurred. A ventilation system which can provide adequate air movement is crucial to maintain the air quality in indoor swimming pool