Analisis of Human Exposure to Chloroform in a Hot Tub
Abstract Hot tubs are very popular across America due to their relaxation as well as health benefits. Hot tubs have been attributed health benefits ranging from relief of muscle and joint pain, to help in treatment of HIV and other viral infections. Because of this, many people own hot tubs and many more go to health spas where they can use them. On the other hand, hot tubs are not that easy to maintain. A consistent disinfectant level must be maintained in order to inhibit the growth of bacteria which could cause infections to the people who use them. The disinfectant of choice for most hot tubs is chlorine, mainly because of its effectiveness, persistence in the water, and the familiarity with its properties. Since the 70’s, attention has been brought to chlorine disinfection by products and their dangers. These byproducts have been shown to be formed when the free chlorine reacts with NOM (natural organic material) in the water. In this report the focus will be on chloroform, one compound of the trihalomethane group, which has been showed to be a human carcinogen. It is the purpose of this paper to assess exposure to chloroform through the dermal and inhalation routes while using an indoor hot tub by creating a worst case scenario, which should exceed the real concentrations and exposure. In order to make this assessment, it is necessary to know the air and water chloroform concentrations while the hot tub is being used. This was done by using data form national surveys that measured chloroform concentrations in water. This concentration was found to be 350 μg/l, and this will be the base concentration. After the water concentration is known, then mass balance equations can be used to determine the air concentrations depending on the air change rate of the room and the scenario being studied. The results from the analysis vary depending on the scenario. Exposure concentration vary from a high of 630 μg/l in air and 3500 μg/l in water for the
References: - Formation of disinfection by-products in chlorinated swimming pool water; H. Kim, J. Schim, S. Lee; Chemosphere 46 (2002) 123-130
- New England Journal of Medicine; 342:218-219 January 2000 Number 3