M Cho1, J Yoon. 1. School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
Abstract
AIM: This study investigates the inactivation of Cryptosporidium parvum using the OH radical and reports the OH radical CT (OH radical concentration x contact time) values for C. parvum inactivation. METHODS AND RESULTS: Although a wealth of information has demonstrated the efficacy of the microbial inactivation activity of the OH radical, no studies have performed a quantitative estimation of the OH radical for C. parvum inactivation. The CT value of the OH radical required for 2 log C. parvum inactivation was measured with two OH radical-generating systems, photo/ferrioxalate and photo/TiO2. The OH radical was approx. 10(4)-10(7)-fold more effective for microbial inactivation than other popular chemical disinfectants such as ozone, chlorine dioxide and free chlorine. CONCLUSIONS: The OH radical appears to be suitable for microbial inactivation with a calculated CT value required for 2 log C. parvum inactivation of 9.3 x 10(-5) mg min l(-1). SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first report of an investigation on the role of the OH radical in the photo/ferrioxalate and photo/TiO2 systems and on the OH radical CT required for C. parvum inactivation.
AIM: This study investigates the inactivation of Cryptosporidium parvum using the OH radical and reports the OH radical CT (OH radical concentration x contact time) values for C. parvum inactivation. METHODS AND RESULTS: Although a wealth of information has demonstrated the efficacy of the microbial inactivation activity of the OH radical, no studies have performed a quantitative estimation of the OH radical for C. parvum inactivation. The CT value of the OH radical required for 2 log C. parvum inactivation was measured with two OH radical-generating systems, photo/ferrioxalate and photo/TiO2. The OH radical was approx. 10(4)-10(7)-fold more effective for microbial inactivation than other popular chemical disinfectants such as ozone, chlorine dioxide and free chlorine. CONCLUSIONS: The OH radical appears to be suitable for microbial inactivation with a calculated CT value required for 2 log C. parvum inactivation of 9.3 x 10(-5) mg min l(-1). SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first report of an investigation on the role of the OH radical in the photo/ferrioxalate and photo/TiO2 systems and on the OH radical CT required for C. parvum inactivation.