Chlorine disinfection of drinking water assessed by flow cytometry: New insights

Abstract The occurrence an d infestations of chlorine-resistant invertebrates in drinking water distributions have attracted concerns on water quality in China, making effective deactivation imperative. This study presents a no vel strategy for nematode ( Caenorhabditis elegans ) deactivation using peroxymonosulfate (PMS)/UV-C. The results indicated that 100% deactivation efficiency was obtained under optimal conditions. An acidic pH and 0.25 mg/L Fe(II) were beneficial to the PMS/UV-C-triggered deactivation of nematodes. A mechanism study demonstrated that was activated by UV-C to produce · OH and · SO 4 - , which resulted in oxidative stress and stimulated the occurrence of cell apoptosis, leading to nematode deactivation. The results reveal PMS/UV-C as an alternative to chlorination in water treatment plants (WTP) or an emergency application when chlorine-resistant invertebrates breed in a second-supply water tank, is a promising strategy for disinfection. This approach afforded the advantages of avoiding the production of chlorine disinfection by-products (DBP) and greater efficacy of nematode deactivation. This work will provide ideas for on-going research efforts into chlorine-resistant invertebrate deactivation, and eventually achieve the direct drinking of municipal tap water.

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Controlling taste and odour events for the city of Philadelphia, USA: a case study

Water Science & Technology Water Supply ◽

10.2166/ws.2008.060 ◽

2008 ◽

Vol 8 (2) ◽

pp. 135-141 ◽

Cited By ~ 1

Author(s):

I. H. (Mel) Suffet ◽

Gary Burlingame ◽

Erin Mackey

Keyword(s):

Drinking Water ◽

Early Warning ◽

Distribution System ◽

Warning System ◽

Consumer Complaints ◽

Chlorine Disinfection ◽

Drinking Waters ◽

Year 2000 ◽

The City

The overall goal of this case study is to describe the history and present methods that the Philadelphia Water Department (PWD) uses to address its on-going earthy and musty drinking water T&O problems. The Philadelphia Water Department has developed a baseline for its water's aesthetic qualities since the early 1980’s. Philadelphia feels it has sufficient resources to control taste and odour problems. However, when directly asked, only 61–64% of the consumers are satisfied with the taste and odour of Philadelphia's drinking waters. A taste and odour early warning system is being developed for the two drinking water sources, the Delaware and Schuylkill rivers. Secondly, routine T&O panels and chemical analysis of geosmin and MIB are completed. Since the year 2000, 10 ng/L has become an early warning wake-up call for PWD. When higher levels are observed, testing is a priority, the source of the T&O is investigated and consumer complaints are monitored carefully. Present water treatment plants are conventional with chlorine disinfection, coagulation/sedimentation, rapid dual media filtration and final chloramination. The PWD uses powdered activated carbon, river water bypass and hydraulic changes in the distribution system to minimise odour events.

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Flow Cytometry as an Operational Tool to Improve Particle Removal in Drinking Water Treatment

Chemical Water and Wastewater Treatment VI ◽

10.1007/978-3-642-59791-6_14 ◽

2000 ◽

pp. 147-157

Author(s):

O. Bergstedt ◽

H. Rydberg ◽

L. Werner

Keyword(s):

Flow Cytometry ◽

Drinking Water ◽

Water Treatment ◽

Drinking Water Treatment ◽

Particle Removal ◽

Operational Tool

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Factors Affecting the Genotoxicity of Drinking Water

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.922 ◽

2012 ◽

Vol 518-523 ◽

pp. 922-927

Author(s):

Zhi Zhen Xu ◽

Dong Sheng Wang ◽

Rong Zhang ◽

Shi Chuan Tang

Keyword(s):

Drinking Water ◽

Sample Preparation ◽

Acid Solution ◽

Aquatic Ecosystem ◽

Ammonia Nitrogen ◽

Solution Ph ◽

Factors Affecting ◽

Chlorine Disinfection ◽

Umu Test ◽

Genotoxic Compounds

The genotoxicity of drinking water have received increased attention in recent years to assess aquatic ecosystem safety. The factors affecting the genotoxicity of drinking water, including sample preparation, the concentration of bromide and ammonia nitrogen (NH3-N), were investigated using umu test. The result showed that sample preparation and bromide could significantly influence the genotoxicity of drinking water. During sample preparation, 1 and 2 L waters concentrated were suitable for umu test and the highest yield for genotoxic compounds was obtained from acid solution (pH 2) when ethyl acetate served as the eluant. Bromide could substantially increase the genotoxicity of drinking water after chlorine disinfection. The genotoxicity of drinking water could not be increased with increasing NH3-N concentration.

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