Impact of UV disinfection on the potential of model organic-nitrogen precursors to form chlorination by-products in swimming pool water

Abstract

The article presents the results of experiments on the potential of model solutions of urea, creatinine, glycine, histidine, and arginine to form several organic chlorination by-products. These precursors are the main organic-nitrogen compounds, whose sources in swimming pool water are sweat and urine of bathers. In the article, the formation potential of the following by-products has been presented and discussed: trichloromethane; monochloroacetic acid; dichloroacetic acid; trichloroacetic acid; trichloroacetonitrile; dichloroacetonitrile; 1,1-dichloropropanone; 1,1,1-trichloropropanone; chloral hydrate; and chloropicrin. The test on by-products formation potential was applied to conduct the experiments, and 24-h incubation time was applied for the swimming pool water samples, disinfected in three variants of treatment: (1) chlorination alone; (2) chlorination and Ultraviolet (UV) irradiation (cumulative dose 23.5 kJ/m2); and (3) chlorination and UV irradiation (cumulative dose 47 kJ/m2). The low-pressure UV lamp by Heraeus was used to irradiate the samples. The results of experiments have been discussed and analyzed to study the influence of UV radiation on the reactivity of individual model precursors and their potential to form halogenated organic chlorination by-products.