[Exposure to chloroform in persons frequenting an indoor swimming pool]

Exposure to chloroform (CHCl3) in indoor swimming pool swimmers. CHCl3 presence has been evidenced many times in water and air of indoor pools as a consequence of water chlorination with sodium hypochlorite or other chlorinated disinfectants. In previous studies CHCl3 in environmental air appeared at a high concentration within one meter over the surface of the water and was correlated to the number of swimmers inside the pool. CHCl3 has also been evidenced in blood serum samples of people present at the swimming pool, at different levels depending on: the concentration in the environmental air, the intensity and the length of the sport activity and the number of swimmers in the pool. At the end of the swimming session CHCl3 concentration tends to lower quickly and usually is no longer detectable within half an hour. Other studies have evidenced CHCl3 in breath samples (alveolar air) of a volunteer subject who swam one hour every day in an indoor pool in Modena. The spirometric parameters of the same subject were evaluated in order to estimate his CHCl3 uptake during time spent at the swimming pool, both resting and swimming in different modes. In the present paper the A.A. report data about CHCl3 exposure, intake and uptake bin five agonistic swimmers (three males and two females), members of the same sport association, and regularly attending the same indoor swimming pool in Modena. The five subjects have been examined during four different sessions. Within every session the samples were collected in five different moments according to the following scheme: 1) Hygiene Institute: samples of blood, alveolar air, environmental air. 2) Swimming pool, after 1 hour sitting near the pool edge: samples of alveolar air, environmental air (within 1 m on the water surface). 3) Swimming pool, after 1 hour swimming: samples of blood, alveolar air, environmental air (within 1 m on the water surface). 4) Hygiene Institute, 1 hour after the end of the swimming time: samples of alveolar air, environmental air. 5) Hygiene Institute, 30 min after the previous sampling: samples of alveolar air, environmental air. Spirometric parameters have been evaluated in every subject, after resting and swimming (point 2 and 3). CHCl3 uptake has been calculated using the following formula: U = V(CI--CA)t where: U = uptake (microgram/h) V = pulmonary ventilation (l/min) CI = inspired (environmental) concentration (microgram/m3) CA = alveolar concentration (microgram/m3) t = exposure time (min) CHCl3 levels after swimming always appeared quite high; however low levels were evidenced also before exposure (point 1).(ABSTRACT TRUNCATED AT 400 WORDS)