Last week we reviewed the history and current use of chlorination in the treatment of drinking water. Our discussion highlighted a number of potential risks associated with chlorine and some of its reaction products. 1 But what are the alternative methods currently under study for disinfecting public water supplies? Which organizations in the US and abroad are concerned with chlorination and wa...

Comparative studies on chlorination and methylation reactions have been carried out to afford chloromethyl(methyl)silanes. For chlorination reactions, three types of initiators, viz., azobisisobutyronitrile, benzoyl peroxide and dicumyl peroxide have been studied at different reaction conditions, e.g., solvent, temperature, time duration of reaction and molar ratio of reactants in view to get o...

Water samples from 3 indoor swimming pool facilities were tested to evaluate UV-induced effects on swimming pool water chemistry. Concentration change of several DBPs was investigated in experiments including medium pressure UV treatment with and without chlorine and post-UV chlorination. Post-UV chlorine consumption increased, dose-dependently, with UV treatment dose. A clear absence of trihal...

The direct chiral Lewis acidic enantioselective chlorination and fluorination of beta-keto phosphonates is presented; the chlorination proceeds in high yields and with up to 94% ee using NCS as the chloro source, while the fluorination with (PhSO2)2NF (NFSI) gives the optically active alpha-fluoro-beta-keto phosphonates in moderate to good yields and with up to 91% ee.

OBJECTIVE To assess the effect of exposure to chlorination byproducts during pregnancy on foetal growth and duration of pregnancy. METHODS A population based study was conducted of 137,145 Norwegian children born alive in 1993--5. Information was obtained from the Norwegian medical birth registry, waterwork registry, and social science data service. The outcomes of interest were birth weight,...

Disinfection of reclaimed water prior to reuse is important to prevent the transmission of pathogens. Chlorine is a widely utilized disinfectant and as such is a leading contender for disinfection of reclaimed water. To understand the risks of chlorination resulting from the potential selection of pathogenic bacteria, the inactivation, reactivation and regrowth rates of indigenous bacteria were...

The formation of disinfection by-products (DBPs) from the degradation of N,N-diethyl-3-methyl benzoyl amide (DEET) and ibuprofen (IBP) by the ultraviolet irradiation (UV)/chlorine process and subsequent post-chlorination was investigated and compared with the UV/H2O2 process. The pseudo first-order rate constants of the degradation of DEET and IBP by the UV/chlorine process were 2 and 3.1 times...

This study investigated fates of nine antibiotic-resistant bacteria as well as two series of antibiotic resistance genes in wastewater treated by various doses of chlorine (0, 15, 30, 60, 150 and 300 mg Cl2 min/L). The results indicated that chlorination was effective in inactivating antibiotic-resistant bacteria. Most bacteria were inactivated completely at the lowest dose (15 mg Cl2 min/L). B...