Identification of New Ozone Disinfection Byproducts in Drinking Water

Abstract

Using a combination of spectral identification techniquesgas chromatography coupled with low- and high-resolution electron-impact mass spectrometry (GC/EI-MS), low- and high-resolution chemical ionization mass spectrometry (GC/CI-MS), and infrared spectroscopy (GC/IR)we identified many drinking water disinfection byproducts (DBPs) formed by ozone and combinations of ozone with chlorine and chloramine. Many of these DBPs have not been previously reported. In addition to conventional XAD resin extraction, both pentafluorobenzylhydroxylamine (PFBHA) and methylation derivatizations were used to aid in identifying some of the more polar DBPs. Many of the byproducts identified were not present in spectral library databases. The vast majority of the ozone DBPs identified contained oxygen in their structures, with no halogenated DBPs observed except when chlorine or chloramine was applied as a secondary disinfectant. In comparing byproducts formed by secondary treatment of chlorine or chloramine, chloramine appeared to form the same types of halogenated DBPs as chlorine, but they were generally fewer in number and lower in concentration. Most of the halogenated DBPs that were formed by ozone−chlorine and ozone−chloramine treatments were also observed in samples treated with chlorine or chloramine only. A few DBPs, however, were formed at higher levels in the ozone−chlorine and ozone−chloramine samples, indicating that the combination of ozone and chlorine or chloramine is important in their formation. These DBPs included dichloroacetaldehyde and 1,1-dichloropropanone.

Use of mechanism-based structure-activity relationships analysis in carcinogenic potential ranking for drinking water disinfection by-products.

“…First, the U.S. EPA compiled a list of DBPs to consider for prioritization. More than 600 DBPs from various disinfectant combinations that have been identified and cataloged by the U.S. EPA (20) served as an important reference. Additional DBPs were subsequently added as new information became available (21,22).…”

Treatment of micropollutants in municipal wastewater: Ozone or powdered activated carbon?

“…For example, undesirable toxic oxidation by-products such as nitrosamines N-Nitrosodimethylamine (NDMA), bromate or formaldehyde can be formed Richardson, 2003;Wert et al, 2007), potentially increasing the toxicity compared to non-ozonated wastewater (Petala et al, 2006;Petala et al, 2008;Stalter et al, 2010a;Stalter et al, 2010b). These oxidation products are usually more easily biodegradable and can be partially removed during biological post-filtration Richardson et al, 1999;Stalter et al, 2010a;Stalter et al, 2010b).…”

THMs precursor removal by an integrated process of ozonation and biological granular activated carbon for typical Northern China water

“…Some researchers have found that the use of ozonation in the water treatment process results in a decrease in the formation of THMs and HAAs upon subsequent chlorination [7][8][9]. An increase in the ozone dosages results in a concomitant decrease in the concentrations of THMs and HAAs that formed from subsequent chlorination [10][11][12][13].…”