Reviews - Large Surveys - Regional Studies - Intensive Analysis - HNMs - Haloaldehydes - Halobenzoquinones

Single DBP - Other Reviews - Other Large Studies

(See also: DBP Degradation)


Major Reports & Review Papers on Occurrence of DBPs
Citation Notes Abstract
Richardson, S.D. (2011) Disinfection Byproducts: Formation and Occurrence in Drinking Water, In: The Encyclopedia of Environmental Health. Nriagu, J.O. (ed), pp. 110-136, Elsevier, Burlington, MA.

An update of her 1998 review

most complete listing of all identified DBPs

Krasner, S.W. (2009) The formation and control of emerging disinfection by-products of health concern. Philosophical Transactions of the Royal Society a-Mathematical Physical and Engineering Sciences 367(1904), 4077-4095.   When drinking water treatment plants disinfect water, a wide range of disinfection by-products (DBPs) of health and regulatory concern are formed. Recent studies have identified emerging DBPs (e.g. iodinated trihalomethanes (THMs) and acids, haloacetonitriles, halonitromethanes (HNMs), haloacetaldehydes, nitrosamines) that may be more toxic than some of the regulated ones (e.g. chlorine- and bromine-containing THMs and haloacetic acids). Some of these emerging DBPs are associated with impaired drinking water supplies (e.g. impacted by treated wastewater, algae, iodide). In some cases, alternative primary or secondary disinfectants to chlorine (e.g. chloramines, chlorine dioxide, ozone, ultraviolet) that minimize the formation of some of the regulated DBPs may increase the formation of some of the emerging by-products. However, optimization of the various treatment processes and disinfection scenarios can allow plants to control to varying degrees the formation of regulated and emerging DBPs. For example, pre-disinfection with chlorine, chlorine dioxide or ozone can destroy precursors for N-nitrosodimethylamine, which is a chloramine by-product, whereas pre-oxidation with chlorine or ozone can oxidize iodide to iodate and minimize iodinated DBP formation during post-chloramination. Although pre-ozonation may increase the formation of trihaloacetaldehydes or selected HNMs during post-chlorination or chloramination, biofiltration may reduce the formation potential of these by-products.


Large National Surveys
Citation Notes Abstract

Francis, R.A., J.M. Vanbriesen, and M.J. Small. 2010. Bayesian Statistical Modeling of Disinfection Byproduct (DBP) Bromine Incorporation in the ICR Database. Environmental Science & Technology 44:1232-1239. Supplemental Info

ICR data Statistical models are developed for bromine incorporation in the trihalomethane (THM),trihaloacetic acids (THAA), dihaloacetic acid (DHAA), and dihaloacetonitrile (DHAN) subclasses of disinfection byproducts (DBPs) using distribution system samples from plants applying only free chlorine as a primary or residual disinfectant in the Information Collection Rule OCR) database. The objective of this study is to characterize the effect of water quality conditions before, during, and post-treatment on distribution system bromine incorporation into DBP mixtures. Bayesian Markov Chain Monte Carlo (MCMC) methods are used to model individual DBP concentrations and estimate the coefficients of the linear models used to predict the bromine incorporation fraction for distribution system DBP mixtures in each of the four priority DBP classes. The bromine incorporation models achieve good agreement with the data. The most important predictors of bromine incorporation fraction across DBP classes are alkalinity, specific UV absorption (SUVA), and the bromide to total organic carbon ratio (Br:TOC) at the first point of chlorine addition. Free chlorine residual in the distribution system, distribution system residence time, distribution system pH, turbidity, and temperature only slightly influence bromine incorporation. The bromide to applied chlorine (Br:Cl) ratio is not a significant predictor of the bromine incorporation fraction (BIF) in any of the four classes studied. These results indicate that removal of natural organic matter and the location of chlorine addition are important treatment decisions that have substantial implications for bromine incorporation into disinfection byproduct in drinking waters.
Obolensky, A., and P.C. Singer. 2008. Development and interpretation of disinfection byproduct formation models using the Information Collection Rule database. Environmental Science & Technology 42:5654-5660. Supplemental Info ICR data Multiple linear regression models were used to examine relationships between water quality, treatment, and disinfection byproduct (DBP) formation in Information Collection Rule field data. Finished water models were specified using a cross-validation approach based on data for 225 free chlorine treatment plants. Turbidity, bromide, temperature, alkalinity, total organic carbon, ultraviolet absorbance at 254 nm, pH, chlorine residual, chlorine consumed, and chlorine contact time were employed as independent variables. Important trends within the trihalomethane, dihaloacetic acid, and trihaloacetic acid classes were observed. Bromide was a significant predictor for all DBP species and its influence changed in sign and magnitude with the extent of bromine substitution. A similar pattern followed by alkalinity suggested it plays an important role as an indicator of natural organic matter hydrophobicity and reactivity. Chlorine consumed and organic precursor variables were significant predictors in almost all DBP species models, exhibiting trends opposite to those for alkalinity and bromide. Temperature was the most significant variable in chloroform and chloral hydrate models and its significance declined with increasing bromine substitution within the trihalomethane class. pH had a strong positive influence on chloroform formation, a negative influence on trihaloacetic acid formation, and no influence on dihaloacetic acid formation.
Obolensky, A., P.C. Singer, and H.M. Shukairy. 2007. Information collection rule data evaluation and analysis to support impacts on disinfection by-product formation. Journal of Environmental Engineering-ASCE 133:53-63. ICR data Information Collection Rule (ICR) water quality and treatment data were screened from an end-user's perspective and data distributions were developed based on the screened data set. Questionable data were flagged and missing categorical variables were replaced where possible. Sparseness of flagged data indicated a high level of ICR data quality while recovery of missing descriptors substantially amplified the data set. Data patterns demonstrated anticipated relationships between disinfection practices and water quality: plants with high concentrations of organic precursors preferentially employed chloramines and avoided prechlorination; plants with high bromide levels also tended to employ chloramines although bromide did not impact prechlorination practice. Though plants employing chloramination used significantly higher chlorine doses than plants using only free chlorine, when normalized to total organic carbon (TOC) this difference largely disappeared. The median ICR chlorine to TOC ratio was 1.54 Mg Cl-2/mg C. Applied chlorine to ammonia-nitrogen ratios at chloramine plants varied widely but the median value was near the theoretical 1 : 1 molar ratio. Significantly higher bromide to TOC ratios at ground water plants, compared to surface water plants, resulted from the typically lower TOC and higher bromide levels in ground waters.
Obolensky, A., and P.C. Singer. 2005. Halogen substitution patterns among disinfection byproducts in the information collection rule database. Environmental Science & Technology 39:2719-2730. Supplemental Info ICR data Disinfection byproduct halogen substitution patterns were examined using Information Collection Rule data. A new metric was developed to quantify and compare extents of specific halogen substitution in different byproduct classes. Bromine substitution in four byproduct classes ranged widely across 6565 samples but strong interdependencies existed between classes on an individual sample basis. Bromine substitution in dihaloacetic acids and trihalomethanes was comparable whereas bromine substitution in trihaloacetic acids and dihaloacetonitriles tended to be 10% lower and 60% higher than in trihalomethanes, respectively. However, these bromine substitution measurements were significantly impacted by censored data handling because reporting limit left-censoring increased with the number of bromine substituents in each class and minimum reporting levels varied between and within classes. Correlation among extents of bromine substitution in the four byproduct classes examined motivated their treatment as a multivariate response with application of a test for multivariate outliers. The test was effective at exposing inconsistencies indicative of data entry or analytical error. This work shows that disinfection byproduct data with full homologue series for multiple compound classes contain redundant information in the form of expected interdependencies among species. Application to quality assurance is demonstrated in this paper. Further applications to modeling and monitoring design are anticipated.
McGuire et al., 2002; ICR Data Analysis; AWWARF 90947 Multi-chapter compilation of ICR data and analysis  


Smaller Regional Studies
Citation Notes Abstract
Chaib, E., and D. Moschandreas. 2008. Modeling daily variation of trihalomethane compounds in drinking water system, Houston, Texas. Journal of Hazardous Materials 151:662-668. THMs in Houston Total trihalomethanes (TTHM) concentrations vary widely and periodically between 70 and 130 ppb. Data from the National Environmental Services Laboratory, Houston, Texas indicate that pH and free residual chlorine contribute minimally to the wide variability of TTHM levels. Temperature variation in drinking fluctuates from 11 to 27 degrees C. The objective of this research is to formulate a model that delineates more clearly the daily variations of the most prevalent volatile trihalomethane by-products: chloroform (CHCl3), bromodichloromethane (CHBr2Cl), and bromoform (CHBr3) levels from drinking water. This model simulates the daily fluctuation of THM at a single location and at any time during the day as a function of the water temperature and the average concentration of TTHM, which can be estimated. The hypothesis of this study is that observed daily fluctuations of TTHM, CHCl3, CHCl2Br, CHClBr2, and CHBr3 are periodic. This hypothesis is tested using autocorrelation functions and it is shown that for the series of pH the correlation coefficient is maximal at zero lags, rapidly decreases to zero, and increases again between 4- and 6-h period. Such pattern suggests random fluctuation unrelated to time. However, the series of free residual chlorine, temperature, TTHM, CHCl3, CHCl2Br, CHClBr2, and CHBr3 suggest a different pattern. The correlation coefficient increases when the time-shift approaches 24h. These repetitions in fluctuation of content over a 24-h period are statistically significant. The model formulated in this study provides insights in TTHM variation and is a necessary tool to reduce the error when estimating potential risk from exposure to trihalomethane compounds in drinking water system. In general, calculation of potential risk by using a value measured early morning or late afternoon concentrations were found minimal lead to an underestimation of the population risk.


Intensive Study of a Few Samples
Citation Notes Abstract
Richardson, S.D., Thruston, A.D., Krasner, S.W., Weinberg, H.S., Miltner, R.J., Schenck, K.M., Narotsky, M.G., McKague, A.B. and Simmons, J.E. (2008) Integrated disinfection by-products mixtures research: Comprehensive characterization of water concentrates prepared from chlorinated and ozonated/postchlorinated drinking water. Journal of Toxicology and Environmental Health-Part a-Current Issues 71(17), 1165-1186.   This article describes the disinfection by-product (DBP) characterization portion of a series of experiments designed for comprehensive chemical and toxicological evaluation of two drinking-water concentrates containing highly complex mixtures of DBPs. This project, called the Four Lab Study, involved the participation of scientists from four laboratories and centers of the U. S. Environmental Protection Agency (EPA) Office of Research and Development, along with collaborators from the water industry and academia, and addressed toxicologic effects of complex DBP mixtures, with an emphasis on reproductive and developmental effects that are associated with DBP exposures in epidemiologic studies. Complex mixtures of DBPs from two different disinfection schemes (chlorination and ozonation/postchlorination) were concentrated successfully, while maintaining a water matrix suitable for animal studies. An array of chlorinated/brominated/iodinated DBPs was created. The DBPs were relatively stable over the course of the animal experiments, and a significant portion of the halogenated DBPs formed in the drinking water was accounted for through a comprehensive qualitative and quantitative identification approach. DBPs quantified included priority DBPs that are not regulated but have been predicted to produce adverse health effects, as well as those currently regulated in the United States and those targeted during implementation of the Information Collection Rule. New by-products were also reported for the first time. These included previously undetected and unreported bromo- and chloroacids, iodinated compounds, bromo- and iodophenols, and bromoalkyltins.



(related info may be found in: DBP Degradation and Nonregulated DBP pages)
Citation Notes Abstract
Chu, W.H. and Gao, N.Y. (2009) Determination of Nitrogenous Disinfection Byproducts Chloroacetamides in Drinking Water by Gas Chromatography-Mass Spectrometry. Chinese Journal of Analytical Chemistry 37(1), 103-106.   A new method for the determination of nitrogenous disinfection byproducts chloroacetamides (CAcAms) in drinking water by gas chromatography mass spectrometry (GC-MS) is described. In the method, the effects of different detecting instrument (GC/ECD and GC/MS) and sample pretreatment were investigated. Direct liquid-liquid extraction-GC/MS method was superior to acid-catalyzed hydrolysis + GC/ECD according to recovery comparison, and extraction effect of ethyl acetate (ETAC) excels methyl tert-butyl ether (MTBE). Good relativeity (r > 0.9995) was obtained when the linear range was 10 - 1000 mu g/L. The recoveries of CAcAms were 82.0% - 111.9%. The relative standard deviations were less than 10.0%. The determination limit is less than 1 mu g/L. The advantage of this method is simple, rapid and sensitive.
Choi, Y.W. and Reckhow, D.A. (2004) Fluorimetric determination of dichloroacetamide by RPLC with postcolumn detection. Bulletin of the Korean Chemical Society 25(6), 900-906.   An RPLC-postcolumn detection method has been developed for the fluorimetric determination of dichloroacetamide (DCAD) in water. After ammonia and DCAD were separated on a C-18 nonpolar stationary phase with 2.5% methanol-0.02 M phosphate buffer at pH 3, the column eluant was reacted with post column reagents, o-phthaldialdehyde (OPA) and sulfite ion at pH 11.5, to produce a highly fluorescent isoindole fluorophore, which was measured with a fluorescence detector (lambda(ex) = 363 nm, lambda(em) = 425 nm). With the optimized conditions for RPLC and the postcolumn derivatization, the calibration curve was found to be linear in the concentration ranges of 0.5 and 20 muM for DCAD, and the detection limit for DCAD was 0.18 muM (23 mug/L). This corresponded to 18 pmol per 100 muL injection volume for a signal-to-noise ratio of 3, and the repeatability and reproducibility of this method were 1.0% and 2.5% for five replicate analyzes of 2 muM DCAD, respectively. The degradation yields DCAD to ammonia were 94 and 99%, and the percent recoveries of DCAD from 4 and 6 muM DCAD-spiked tap water were shown mean more than 97%


Citation Notes Abstract


Citation Notes Abstract
Dabrowska, A., B.K. Hordern, and J. Nawrocki. 2005. Aldehydes formation during water disinfection by ozonation and chlorination process, p. B140-B146, In T. D. Lekkas, ed. Proceeding of the 9th International Conference on Environmental Science and Technology Vol B - Poster Presentations.
  The aim of our study was to discuss the problem of biodegradable by-products formed during water disinfection by both: ozonation and chlorination process. We compared the range of productivity of aldehydes in three different waters treated with chlorine and chlorine dioxide with that observed usually for ozonation. Aldehydes were investigated as representative organic compounds, formed together with the other biodegradable organic by-products, relatively more unstable in water and difficult to detect. Our investigations were concentrated on the Cl-2 and CIO2 disinfectants, which are used generally in the final stage of water treatment and can potentially influence aldehyde formation in distribution systems.
Dabrowska, A., A. Borcz, and J. Nawrocki. 2003. Aldehyde contamination of mineral water stored in PET bottles. Food Additives and Contaminants 20:1170-1177.   Aldehyde contaminations that might accompany production of mineral water stored in PET bottles were investigated. One of the production lines of carbonated mineral water in Poland was monitored and PET bottles commonly used for mineral water storage were evaluated. Formaldehyde and acetaldehyde were the most important carbonyls identified in series of bottled water samples, but also propanal, nonanal and glyoxal were found in water samples from the production line. Aldehydes are present everywhere in the environment and can be determined even in pure water at low mug l(-1) levels. It was observed that the concentration of acetaldehyde in water stored in PET bottles depended mainly on the concentration of acetaldehyde in PET material and could reach more than 200 mug l(-1). The temperature, time of storage and concentration of carbon dioxide gas contribute to the migration of aldehydes from bottle walls to mineral water. Higher pressure of the carbonated waters and not CO2 itself or lower pH of waters seems responsible for higher concentration of acetaldehyde.
Dabrowska, A., J. Swietlik, and J. Nawrocki. 2003. Formation of aldehydes upon ClO2 disinfection. Water Research 37:1161-1169.   Carbonyl compounds are considered to be the most common ozonation by-products. Apart from well-known chlorites and chlorates, chlorine dioxide (ClO2) also generates organic by-products. The goal of this paper is an investigation into the influence of disinfection with ClO2 on the aldehydes formation. Three types of waters were disinfected with different doses Of ClO2 at the various pH values. The results of size exclusion chromatography show that the reaction Of ClO2 with humic fraction of natural organic matter proceeds mainly on an aromatic part of the molecules. The results obtained indicate that the level of carbonyls concentration can significantly increase with the time Of ClO2 reaction with carbonyl precursors in treated water. There is no noticeable correlation between quantity of aldehydes and pH value of disinfected water. The range of "productivity" of aldehydes in water treated with chlorine dioxide is similar to the range estimated for the carbonyls formed upon ozonation.
Nawrocki, J., J. Swietlik, U. Raczyk-Stanislawiak, A. Dabrowska, S. Bilozor, and W. Ilecki. 2003. Influence of ozonation conditions on aldehyde and carboxylic acid formation. Ozone-Science & Engineering 25:53-62.   The influence of ozonation conditions (i.e. ozone dose and contact time) on the aldehyde and carboxylic acids formation was studied on a pilot scale. The data derived from changes in the molecular weight distribution of natural organic matter (NOM) and the concentration of residual ozone can be applied to a selection of the optimum ozonation conditions. The results confirm the relative ease with which ozone reacts with the organic matter. The short contact time (4-6 min) appeared to be sufficient for the reaction. The higher molecular weight (1600 D) fraction of NOM seems to be slightly more reactive to ozone than the lower molecular weight fraction (500 D). It was also observed that carboxylic acids had been formed at much higher quantities than aldehydes. Two differently acting groups of aldehydes were identified. The concentration of the first one (i.e. formaldehyde, acetaldehyde) strongly depends on ozone dose, while the concentration of the second group of aldehydes (i.e. glyoxal, methylglyoxal) seems to be relatively independent of the ozone dose.
Nawrocki, J., A. Dabrowska, and A. Borcz. 2002. Investigation of carbonyl compounds in bottled waters from Poland. Water Research 36:4893-4901.   Poly(ethylene terephtalate) (PET) bottles are commonly used for storing mineral water. The migration of carbonyl compounds from PET bottles into mineral water was observed. Carbonation of water, sunlight and high temperature enhance the process of migration. Formaldehyde, acetaldehyde and acetone were the most important carbonyls identified in series of bottled water samples. The concentration of carbonyls can change depending on the time of storage as well as storage conditions. It was identified particularly high concentration of acetaldehyde (more than 100 mug 1(-1)) in samples of mineral water saturated with CO2 gas.

(most HBQ references are in: Non-Regulated DBPs, see also: DBP Methods, DBP Degradation and DBP Health)
Citation Notes Abstract
Zhao, Y.L., J. Anichina, X.F. Lu, R.J. Bull, S.W. Krasner, S.E. Hrudey, and X.F. Li. 2012. Occurrence and formation of chloro- and bromo-benzoquinones during drinking water disinfection. Water Research 46:4351-4360. Supplemental Information.
data from 7 plants, 5 using chloramines and 2 using free chlorine Consumption of chlorinated drinking water has shown somewhat consistent association with increased risk of bladder cancer in a series of epidemiological studies, but plausible causative agents have not been identified. Halobenzoquinones (HBQs) have been recently predicted as putative disinfection byproducts (DBPs) that might be of toxicological relevance. This study reports the occurrence frequencies and concentrations of HBQs in plant effluents from nine drinking water treatment plants in the USA and Canada, where four common disinfection methods, chlorination, chloramination, chlorination with chloramination, and ozonation with chloramination, are used. In total, 16 water samples were collected and analyzed for eight HBQs: 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (2,6-DC-3-MBQ), 2,3,6-trichloro-1,4-benzoquinone (2,3,6-TriCBQ), 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,3-dibromo-5,6-dimethyl-1,4-benzoquinone (2,3-DB-5,6-DM-BQ), tetrabromo-1,4-benzoquinone (TetraB-1,4-BQ), and tetrabromo-1,2-benzoquinone (TetraB-1,2-BQ). Of these, 2,6-DCBQ 2,6-DBBQ 2,6-DC-3-MBQ and 2,3,6-TriCBQ were detected in 16, 11, 6, and 3 of the 16 samples with the method detection limit (DL) of 1.0, 0.5, 0.9 and 1.5 ng/L, respectively, using a solid phase extraction and high performance liquid chromatography -tandem mass spectrometry method. The concentrations were in the ranges of 4.5 -274.5 ng/L for 2,6-DCBQ below DL to 37.9 ng/L for 2,6-DBBQ below DL to 6.5 ng/L for 2,6-DC-3-MBQ and below DL to 9.1 ng/L for 2,3,6-TriCBQ. These authentic samples show DCBQ and DBBQ as the most abundant and frequently detectable HBQs. In addition, laboratory controlled experiments were performed to examine the formation of HBQs and their subsequent stability toward hydrolysis when the disinfectants, chlorine, chloramine, or ozone followed by chloramines, reacted with phenol (a known precursor) under various conditions. The controlled reactions demonstrate that chlorination produces the highest amounts of DCBQ while pre-ozonation increases the formation of DBBQ in the presence of bromide. At pH < 6.8, 2,6-DCBQ was observed to be stable, but it was easily hydrolyzed to form mostly 3-hydroxyl-2,6-DCBQ at pH 7.6 in drinking water.
Anichina, J., Zhao, Y.L., Hrudey, S.E., Le, X.C. and Li, X.F. (2010) Electrospray Ionization Mass Spectrometry Characterization of Interactions of Newly Identified Water Disinfection Byproducts Halobenzoquinones with Oligodeoxynucleotides. Environmental Science & Technology 44(24), 9557-9563.   Four halobenzoquinones, 2,6-dibromo-1,4-benzoquinone, 2,6-dichloro-1,4-benzoquinone, 2,6-dichloro-3-methyl-1,4-benzoquinone, and 2,3,6-trichloro-1,4-benzoquinone, were recently identified as drinking water disinfection byproducts. Understanding their interactions with biomolecules could provide useful insights into their potential toxic effects. We report here electrospray ionization mass spectrometry characterization of the interactions between these new halobenzoquinone disinfection byproducts and oligodeoxynucleotides. The study demonstrates that 2,6-dibromo-1,4-benzoquinone exhibits much stronger binding to single- and double-stranded oligodeoxynucleotides than chlorobenzoquinones. The binding affinity of 2,6-dibromo-1,4-benzoquinone to oligodeoxynucleotides is similar to that of ethidium bromide, a well-known intercalator and carcinogen. Tandem mass spectrometry characterization confirms the formation of 1:1 and 2:1 complexes of 2,6-dibromo-1,4-benzoquinone binding to oligodeoxynucleotides. Collision-induced dissociation analysis of these adducts demonstrates neutral loss and charge separation, suggesting that 2,6-dibromo-1,4-benzoquinone binds to oligodeoxynucleotides through partial intercalation and H-bonding modes. The three chlorobezoquinones also form 1:1 adducts with the oligodemmucleotides, but their binding to the oligodeoxynucleotides was much weaker compared to that of 2,6-dibromo-1,4-benzoquinone. The relative binding affinity of the studied disinfection byproducts to oligodeoxynucleotides is in the order of 2,6-dibromo-1,4-benzoquinone>>2,6-dichloro-1,4-benzoquinone > 2,6-dichloro-3methyl-1,4-benzoquinone similar to 2,3,6-trichloro-1,4-benzoquinone, indicating potential structural effects on the interactions of halobenzoquinones with oligodeoxynucleotides.
Zhao, Y.L., Qin, F., Boyd, J.M., Anichina, J. and Li, X.F. (2010) Characterization and Determination of Chloro- and Bromo-Benzoquinones as New Chlorination Disinfection Byproducts in Drinking Water. Analytical Chemistry 82(11), 4599-4605.   We report the characterization and determination of 2,6-dichloro-1,4-benzoquinone and three new disinfection byproducts (DBPs): 2,6-dichloro-3-methyl-1,4-benzoquinone, 2,3,6-trichloro-1,4-benzoquinone, and 2,6-dibromo-1,4-benzoquinone. These haloquinones are suspected bladder carcinogens and are likely produced during drinking water disinfection treatment. However, detection of these haloquinones is challenging, and consequently, they have not been characterized as DBPs until recently. We have developed an electrospray ionization tandem mass spectrometry technique based on our observation of unique ionization processes. These chloro- and bromo-quinones were ionized through a reduction step to form [M + H](-) under negative electrospray ionization. Tandem mass spectra and accurate mass measurements of these compounds showed major product ions, [M + H - HX](-), [M + H - HX - CO](-), [M + H - CO](-), and/or X- (where X represents Cl or Br). The addition of 0.25% formic acid to water samples was found to effectively stabilize the haloquinones in water and to improve the ionization for analysis. These improvements were rationalized from the estimates of pK(a) values (5.8-6.3) of these haloquinones. The method of tandem mass spectrometry detection, combined with sample preservation, solid phase extraction, and liquid chromatography separation, enabled the detection of haloquinones in chlorinated water samples collected from a drinking water treatment plant. The four haloquinones were detected only in drinking water after chlorination treatment, with concentrations ranging from 0.5 to 165 ng/L, but were not detectable in the untreated water. This method will be useful for future studies of occurrence, formation pathways, toxicity, and control of these new halogenated DBPs.


Other Papers with some Occurrence Data
Citation Notes Abstract
Richardson, S.D. (2012) Environmental Mass Spectrometry: Emerging Contaminants and Current Issues. Analytical Chemistry 84(2), 747-778.
The Biennial Review in An. Chem.  
Richardson, S.D. (2010) Environmental Mass Spectrometry: Emerging Contaminants and Current Issues. Analytical Chemistry 82(12), 4742-4774. The Biennial Review in An. Chem.  



Large DBP Studies with some Occurrence Data
Citation Notes Abstract