Study of removal effect on Mesocyclops leukarti with oxidants

Abstract

Cyclops of zooplankton propagates prolifically in eutrophic waterbody and it cannot be exterminated by conventional disinfection process. The mutagenicity of Mesocyclops leukarti and its extermination with oxidants in a drinking waterworks in China were studied. Among five oxidants for use in bench-scale, chlorine dioxide is the most effective and the potassium permanganate is the weakest against Mesocyclops leukarti under the same conditions. Full-scale results showed that Mesocyclops leukarti could be effectively removed from water by 1.0 mg/L chlorine dioxide preoxidation combined with conventional removal physical process. After filtration, chlorite, a by-product of prechlorine dioxide, is stable at 0.45 mg/L, which is lower than the critical value of the USEPA. GC-MS examination and Ames test further showed that the quantity of organic substance and the mutagenicity in water treated by chlorine dioxide preoxidation are obviously less than those of prechlorination.

A study of the properties of chlorine dioxide gas as a fumigant

“…Chlorine dioxide (ClO 2 ) is a powerful oxidant that has a potent antimicrobial activity against bacteria, fungi and viruses [ 1 , 2 , 4 ]. Aqueous ClO 2 is known as an environment-friendly disinfectant and has been successfully employed for the treatment of drinking water [ 3 , 19 , 27 ] because, unlike chlorine, it does not result in the formation of trihalomethanes or react with ammonia to form chloramine in water. Recent studies presented that gaseous ClO 2 also has a potent antimicrobial efficacy [ 6 , 8 , 9 , 10 , 23 , 24 , 25 ].…”

Decontamination of Bacillus subtilis var. niger spores on selected surfaces by chlorine dioxide gas

“…Chlorine dioxide (CD) is well known as an environment-friendly bactericide and has been successfully employed as a biocidal agent in water disinfection (Huang et al, 1997;Radziminski et al, 2002;Bergmann and Koparal, 2005;Zuo et al, 2006) and as a sanitizer for vegetable and fruit surfaces (Han et al, 2000;Mahmoud et al, 2007;Karabulut et al, Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology) ISSN 1673-1581 (Print); ISSN 1862-1783 (Online) www.zju.edu.cn/jzus; www.springerlink.com E-mail: jzus@zju.edu.cn 2009). It is capable of killing Bacillus spores (Chatuev and Peterson, 2010) and Cryptosporidium parvum oocysts (Chauret et al, 2001).…”