title: Occurrence and control of nitrogenous disinfection by-products in drinking water--a review.
abstract: The presence of nitrogenous disinfection by-products (N-DBPs), including nitrosamines, cyanogen halides, haloacetonitriles, haloacetamides and halonitromethanes, in drinking water is of concern due to their high genotoxicity and cytotoxicity compared with regulated DBPs. Occurrence of N-DBPs is likely to increase if water sources become impacted by wastewater and algae. Moreover, a shift from chlorination to chloramination, an option for water providers wanting to reduce regulated DBPs such as trihalomethanes (THMs) and haloacetic acids (HAAs), can also increase certain N-DBPs. This paper provides a critical review of the occurrence and control of N-DBPs. Data collated from surveys undertaken in the United States and Scotland were used to calculate that the sum of analysed halonitromethanes represented 3-4% of the mass of THMs on a median basis; with Pearson product moment correlation coefficients of 0.78 and 0.83 between formation of dihaloacetonitriles and that of THMs and HAAs respectively. The impact of water treatment processes on N-DBP formation is complex and variable. While coagulation and filtration are of moderate efficacy for the removal of N-DBP precursors, such as amino acids and amines, biofiltration, if used prior to disinfection, is particularly successful at removing cyanogen halide precursors. Oxidation before final disinfection can increase halonitromethane formation and decrease N-nitrosodimethylamine, and chloramination is likely to increase cyanogen halides and NDMA relative to chlorination.
authors.affiliation: Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, United Kingdom. tomgbond@hotmail.com
authors.forename: Tom
authors.initials: T
authors.lastname: Bond
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.forename: Michael R
authors.initials: MR
authors.lastname: Templeton
authors.forename: Nigel
authors.initials: N
authors.lastname: Graham
mesh_terms: D000081:Acetamides / Q000737:chemistry; D004202:Disinfectants / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods; D054879:Halogenation; D008697:Methane / Q000031:analogs & derivatives / Q000737:chemistry; D009595:Nitroparaffins / Q000737:chemistry; D009602:Nitrosamines / Q000737:chemistry; D010084:Oxidation-Reduction; D014481:United States; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*; D014881:Water Supply / Q000592:standards
chemical_list: D000081:Acetamides; D004202:Disinfectants; D009595:Nitroparaffins; D009602:Nitrosamines; D014874:Water Pollutants, Chemical; D008697:Methane; C008640:nitromethane