Chlorinated water in swimming pools contains chloroform at elevated levels compared to chlorinated drinking water. Chloroform levels in four indoor swimming pools(swimming pools A, B and C in a city of Korea and swimming pool D in a city of New Jersey in the United States) were examined. The chloroform levels in the water of swimming pool C (city-managed) were shown to be significantly(p=0.0001) different from those of private swimming pools A and B: the mean chloroform levels in the pools A, B, and C are 22.8, 17.8, and 31.1 ㎍/ℓ respectively. Furthermore, all of these chloroform levels are significantly(p=0.0001) different from those of New Jersey: chloroform concentration of the Korean pools ranged from 10.9 ㎍/ℓ to 47.9 ㎍/ℓ with a mean of 23.2 ㎍/ℓ, while it ranged from 27 ㎍/ℓ to 96 ㎍/ℓ with a mean of 64.4 ㎍/ℓ in the New Jersey pool. The disinfection processes would cause part of this difference since the swimming pools in Korea applied both chlorination and ozonation method, while the swimming pool in New Jersey used chlorination method only. It was implied that swimming parameters inconsistently vary, resulting in fluctuation of and no constant accumulation of chloroform in the water with the change of time for the day. A regression analysis showed no relationships between sampling time and chloroform concentrations for the sampling day in the swimming pools of Korea. A F-test indicated no significant difference of chloroform concentrations in the morning and afternoon samples collected in the swimming pools. Ingestion dose was estimated to be 0.58 ㎍ from an hour swimming in a city of Korea, taking into accounting an average of 23.2 ㎍/ℓ in swimming pools in the city. In extreme situation, the ingestion dose was estimated to he 12.0 ㎍ from an hour swimming in a city of Korea.

• Wan Kuen Jo | 조완근