The Determination of Trihalomethanes in Pool Water; Comparison of Saline with Chlorine tablet Chlorination

(Chris Holm and Mike Donnelly)

Abstract

Research indicated that swimming pools contained levels of Trihalomethanes (THMs) significantly higher than the EPA's standard for tap water (80 ppb). To determine THM levels a system consisting of a purge and trap in conjunction with a gas chromatograph/mass selective detector was utilized. Analysis showed, total THM concentration to be 199.5 ng/mL, 159.7ng/mL*, 195.3ng/mL, 196.0ng/mL for each of four sample pools. Though the pools were remarkably consistent in total THM concentrations the level of chloroform was not. Chloroform concentrations of each of the four samples were; 54.4 ng/mL, and 63.1 ng/mL for salt electrolysis pools; and 50.6 ng/mL, 51.1 ng/mL for pools using sodium hypochlorite tablets.