Disinfection By-product Formation Potential Research Articles

Reduction of organic matter and disinfection byproducts formation potential by titanium, aluminum and ferric salts coagulation for micro-polluted source water treatment

Typical Chinese source water has high content of low molecular weight and aromatic protein-like organic matter which is difficult to remove and poses a great challenge to conventional coagulation/flocculation. To investigate coagulation performance of this typical water, this research focused on organic matter removal characteristics and the associated disinfection byproducts formation potentials (DBPFPs) during the coagulation process by titanium salts compared with traditional aluminum and ferric salts. Results showed that based on the dissolved organic matter (DOM) removal, the optimal coagulant dosages of AlCl3, FeCl3 and TiCl4 were 0.5 mM and the optimal initial pH values were 8, indicating that the DOM in the typical Chinese water could be effectively removed through sweeping and adsorption by metal hydroxides rather than the complexation and charge neutralization effect under acidic conditions. Compared these three coagulants, the highest ultra violet absorbance at 254 nm removal rate of 72.9% was achieved by TiCl4. The three-dimensional excitation emission matrix results showed that the removal ability of humic acids by AlCl3 was poorer than FeCl3 and TiCl4. The removal rate of low molecular weight components (1600 Da) by TiCl4 was 20% higher than using AlCl3 and 14% higher than FeCl3. Comparing with AlCl3 and FeCl3, TiCl4 had a better performance on the control of DBPFPs, especially for chloroform and dichloroacetic acid, due to its higher removal ability of aromatic organics. The trihalomethane formation potentials removal rate by TiCl4 was three times higher than that by AlCl3 and twice by FeCl3, by which could be inferred that titanium salts achieved better removal of low molecular weight organic matter than aluminum and ferric salts.

Pilot-scale comparison of cyclically and continuously operated drinking water biofilters: Evaluation of biomass, biological activity and treated water quality

The objective of this pilot study was to evaluate the impact of cyclical (operated 8–12 h per day) and continuous biofilter operation with respect to biomass development, biological enzyme activity and treated water quality (in terms of organics, nutrients and disinfection by-product (DBP) formation potential). Continuously operated biofilters developed greater densities of biomass, as measured by ATP, when compared to cyclically operated filters; reducing the empty bed contact time (EBCT) increased biomass density under continuous flow conditions. However, once normalized to biomass, it was shown that cyclically operated filters exhibited higher enzyme activity, indicating that this method of operation may improve bacterial function. Reduction of organics was generally similar for both continuous and cyclical filters with the same EBCT, however, cyclical filters demonstrated higher variability during the first 4 h following start-up. Overall, HAA formation potential was better controlled by continuously operated filters, due to poor performance by the cyclical filters upon start-up while THM precursors were removed equally well by all filters. To understand the removal capacity for NDMA precursors through biological filters, both naturally occurring NDMA FP and NDMA FP resulting from spiked anthropogenic precursors was monitored through the filter depth. All the filters removed 90% of the naturally occurring NDMA FP within the first 45 cm; cyclical operation resulted in higher reduction of spiked anthropogenic NDMA precursors (50% higher than continuously operated) demonstrating the advantage of routine shut down on overall microbial activity.Tools to monitor and predict biofilter performance are in high demand. Here we present an “effective activity” term which combines enzyme activity with contact time (EBCT). Effective esterase activity was strongly correlated to DOC reduction as a function of filter operation (cyclical or continuous) and EBCT; effective phosphatase activity was indicative of phosphate removal. The results of this study indicate that routine shut down of the filters as this location improved enzyme activity without compromising control of chlorinated DBPs (THMs and HAAs) or NDMA derived from natural and anthropogenic precursors.

Formation kinetics of disinfection byproducts in algal-laden water during chlorination: A new insight into evaluating disinfection formation risk

It is necessary and important to investigate the formation of disinfection byproducts (DBPs) in water treatment systems for the management of disinfection formation risk. In the present study, the formation potential of trichloromethane (TCM) and haloacetic acids in different algal metabolites were compared, and the formation kinetics of these DBPs were investigated. The results indicated that DBP formation potential, the traditional index widely used to evaluate the disinfection formation risk, can represent neither the total precursors of DBPs nor the possible generated amounts of DBPs in drinking water systems. Kinetic analyses showed that the formation of DBPs could be well described by a classical second-order reaction kinetic model and that the actual concentrations of DBPs during chlorination were predictable with the model. The formation of DBPs in drinking water treatment systems was highly dependent on the total precursors of DBPs in water and the formation rate of DBPs with chlorine; the latter is usually underestimated in previous studies. Because of their high reactivity, TCM in hydrophilic extracellular organic matter and trichloroacetic acid in all algal metabolites should be serious considerations in the management of disinfection formation risk.

Removal of disinfection byproduct precursors and reduction in additive toxicity of chlorinated and chloraminated waters by ozonation and up-flow biological activated carbon process

The variations of disinfection byproduct (DBP) precursors and DBPs-associated toxic potencies were evaluated by ozonation, followed by a up-flow biological activated carbon (O3/UBAC) filter treating two reconstituted water samples, featuring either high bromide (105.3 μg/L) or dissolved organic nitrogen (0.73 mg N/L) concentration, respectively. Ozonation contributed to ∼20% decrease in dissolved organic carbon (DOC) concentration at a dosage of 0.7 mg of O3/mg of DOC, but no further reduction in DOC level was observed with an increased dose of 1.0 mg of O3/mg of DOC. When chlorine or preformed monochloramine was used as a disinfectant, UBAC process led to ∼40% reduction in the sum of detected DBP formation potential (FP) due to the removal of precursors at a feasible empty bed contact time of 15 min. The integrated effect of ozonation and UBAC biofiltration decreased the sum of DBP FP by ∼50% including halonitromethanes (THNMs), N-nitrosamines (NAs), and bromate, which increased in the effluent of ozonation. Chloramination produced less DBPs by weight as well as DBPs-associated additive toxic potencies than chlorination. The reduction in additive toxic potencies was generally lower than the removal efficiency of DBP FP after chlor(am)ination of treated waters by O3/UBAC, indicating that the removal of DBPs-associated additive toxic potencies should be focused to better understand on the residual risk to public health in controlling DBP precursors.

Bioavailability of soluble microbial products as the autochthonous precursors of disinfection by-products in aerobic and anoxic surface water

Soluble microbial products (SMPs), as a major part of the effluent organic matter discharged into surface water, may affect the formation of disinfection by-products (DBP) in downstream drinking water treatment plants. In this study, excitation emission matrix fluorescence with parallel factor analysis (EEM-PARAFAC), infrared spectroscopy (IR), high performance size-exclusion chromatography (HPSEC) and 16SrRNA high-throughput sequencing were used to investigate the aerobic and anoxic bioavailability of SMPs in surface water and evaluate their influences on DBP formation upon chlorination in a subsequent drinking water plant. In this study, SMPs were utilized by enriched microbial communities such as Bacteroidetes and Proteobacteria, but the accumulation of SUVA was pronounced during the two oxygen conditions. Biodegraded SMPs had higher humic substructures and lower protein-like components. Due to the presence of SMPs, microbial community compositions were influenced during biodegradation. Moreover, DO was the main factor in biodegradation of SMPs, thus affecting a series of processes, such as microbial compositions, properties of SMPs, DBP formation and reactivity. DBP formation potential decreased after anoxic and aerobic incubations. However, SMPs after aerobic degradation had higher DBP reactivity meanwhile the opposite was found for anoxic incubation. Based on the analysis of IR and HPSEC, it was found that some new substrates or intermediates with MW (220 KDa, <1 KDa) during microbial incubation may contribute to the formation of trihalomethane (THMs), chloral hydrate (CH), dichloroacetonitrile (DCAN) and trichloronitromethane (TCNM) in each DBP sampling episode.

The contribution of atmospheric particulate matter to the formation of CX3R-type disinfection by-products in rainwater during chlorination

Atmospheric particulate matter (PM) can be scavenged by rainfall and contribute dissolved organic matter (DOM) to rainwater. Rainwater may serve as a part or the whole of drinking water sources, leading to the introduction of PM-derived DOM into drinking water. However, little information is available on the role of PM-derived DOM as a remarkable precursor of CX3R-type disinfection by-products (DBPs) in rainwater. In this study, samples were collected from ten occurrences of rainfall in Shanghai and batch experiments were executed to explore the contribution of PM-derived DOM to CX3R-type DBP formation in rainwater and to further understand some of unknowns regarding its characteristics. Results revealed that a part of PM was scavenged by rainfall and the scavenge performance was better for smaller PM. The formation potentials (FPs) of individual CX3R-type DBP were similar among size-isolated PM. TCM was predominant (around 0.5–4.5 μg-C/mg-C) and TCAA was the secondary (around 0.6–3.2 μg-C/mg-C) among all detectable CX3R-type DBPs. Based on the PM removal data and DBP FP results, the contribution of PM-derived DOM to CX3R-type DBP formation in rainwater was modeled. Furthermore, aromatic proteins and soluble microbial product-like compounds were found to be significant compositions, which were reported to be DBP precursors. And low molecular weight (< 10 kDa) DOM derived from total PM and rainwater exhibited higher CX3R-type DBP FPs. DOM fractions with higher SUVA254 and SUVA285 values gave relatively higher yields of CX3R-type DBPs, indicating that aromatic compounds played an important role in DBP formation.

Dynamic variations in dissolved organic matter and the precursors of disinfection by-products leached from biochars: Leaching experiments simulating intermittent rain events

Biochar-leached dissolved organic matter may have a substantial impact on the water quality of receiving water surrounded by biochar-amended fields. In this study, we tracked variations in the spectroscopic characteristics and the disinfection by-products formation potentials of dissolved organic matter (DOM) leached during sequential extraction for three different biochars (BCs), which simulates DOM from BC-amended fields during intermittent rain events. The optical properties of DOM were more dependent on the BC types with different origins (sludge, corn, and rice) rather than on the extraction time. A large amount of DOM was released during the initial period of the extraction (1 day), which was equivalent to 52–60% of the total cumulative organic carbon during 17 days of extraction. The relative contribution of the initial extraction to the total cumulative amounts was greater for the formation potential of trihalomethanes (THMs) per BC (71–82%) compared to those of haloacetic acids (HAAs) or dissolved organic carbon (DOC), suggesting that the leaching behaviors of disinfection byproducts (DBP) precursors from BCs may be different from those of DOC (i.e., bulk DOM). Among the three BCs, corn BC-derived DOM exhibited the highest formation potentials of THMs and HAAs per BC for both the initial and the total cumulative extraction. The specific (or DOC-normalized) THMs formation potential was positively correlated with the ratios of terrestrial humic-like to fulvic-like components, implying condensed aromatic structures could operate as a surrogate for THMs formation of BC-derived DOM. This study provided insight into dynamic leaching behaviors of DOM from BCs and the formation potentials for THMs and HAAs in BC-amended fields under intermittent rainfall.

Chemical characterization and relative toxicity assessment of disinfection byproduct mixtures in a large drinking water supply network

In order to reduce the formation of disinfection by-products (DBPs) during potabilization of water it is necessary to explore the potential of the source water and the applied treatment to generate these chemicals. This is actually more challenging in large drinking water networks that use different source waters to satisfy drinking water demand. In this regard, this work investigated the formation of DBPs in water matrices that are commonly supplied to the city of Barcelona and its metropolitan area. The regulated trihalomethanes and haloacetic acids were the most abundant DBP classes in these waters, followed by haloacetamides and haloacetonitriles or trihalogenated acetaldehydes (THALs). On the contrary, the formation potential of iodo-DBPs was minor. Mixing of drinking water treatment plant finished waters with desalinated water decreased the overall DBP formation potential of the water but resulted in the increased formation of brominated DBPs after long chlorine contact time. The formation of most DBPs was enhanced at high water temperatures (except for Br-THALs) and increasing residence times. Potential cytotoxicity and genotoxicity of the DBP mixtures were mainly attributed to the presence of nitrogen-containing DBPs and HAAs.

Optimization of Coagulation and Ozonation Processes for Disinfection by–Products Formation Potential Reduction

Optimization of coagulation and ozonation processes for removal of disinfection by–products (DBP) formation potential in raw water was conducted by a pilot scale system. Proper poly–aluminum–chloride–sulfates (PACS), pre–ozone and post–ozone dosages are required for improving the removal performance of DBP formation potential to guarantee the safety of drinking water. Considering the treatment performances and economic costs, the optimum PACS, pre–ozone and post–ozone dosages for treating raw water with high organic concentration should be around 8.9 mg/L Al2O3, 0.5 and 2.5 mg/L, respectively. The combined drinking water treatment system of pre–ozonation, coagulation/sedimentation, sand filtration, post–ozonation, granular activated carbon filtration and disinfection is a promising process to reduce DBP formation potential from raw water in southern China. Under the optimum conditions, this combined system removed total trihalomethanes and haloacetic acids formation potential 50.16 and 69.10%, respectively.

Effects of different secondary biological treatment processes followed by flocculation and sand-filtration on subsequent DBPs control from sewage treatment plants

The nature and chlorine reactivity of dissolved organic matter (DOM) in reclaimed water from sewage treatment plants (STPs) are quite important for assessing the risk of wastewater reuse. Elucidating relation between DOM and its fractions characterization with different treatment processes is quite important for selection of treatment processes focusing on disinfection by-products (DBPs) control. In this study, four classical STPs in Beijing (A ∼ D) with different secondary biological treatment processes but all with flocculation and sand-filtration as advanced treatment process were selected to investigate DBPs formation potentials and DOM characterization variation during these processes and their relation. Chloroform, trichloroacetic acid (TCAA) and dichloroacetic acid (DCAA) dominated among four trihalomethanes (THMs) and nine haloacetic acids (HAAs) formation potentials respectively during chlorination of both secondary and sand-filtration effluents with the order of TCAA > chloroform > DCAA. Both THMs and HAAs formation potentials were positively related with DOC percentage for the hydrophobic fractions in the DOM. The bromine incorporation in THMs was obviously higher than that in HAAs. The especially higher bromine incorporation in D STP was probably due to the higher SUVA value in this STP with SBR as secondary biological treatment process comparing to those in the other three STPs. DOC and bromide removal, SUVA decrease were important elements for selecting secondary treatment process considering DBPs control. Flocculation and sand-filtration performed not well in removing DBPs precursors especially for chloroform and DCAA except for C STP, which had higher hydrophobic fraction percentage removal and molecular weight decreasing during the advanced treatment process. FTIR analysis revealed that flocculation and sand-filtration probably removed more aliphatic structures than aromatic or COO structures. The absorption ratio of aromatic CC, COO/aliphatic CH3 peaks in D STP was the highest among the four STPs, which was consistent with the highest bromine incorporation in this STP.

Development of a Chlorine Dosing Strategy for Fresh Produce Washing Process to Maintain Microbial Food Safety and Minimize Residual Chlorine.

The chlorine dosing strategy can be used for fresh produce washing process to enhance the microbial food safety and minimize the DBPs formation potential.

Formation of disinfection by-products in remineralized desalinated seawater with bacterial materials as precursor

As the essential target of disinfection, bacterial materials should also be considered as one type of disinfection by-products precursors (DBPs). This study investigated the disinfection by-products formation potential (DBPFP) of bacterial materials during chlorination and chloramination. The bacterial materials were harvested from mature biofilm developed in remineralized desalinated seawater with different carbon sources. It was observed that calcium and magnesium which were added to desalinated seawater for remineralization could enhance DBPFP of bacterial materials, with magnesium being more effective. The enhancement effect was related to the ability of calcium and magnesium to shift low molecular weight fractions of bacterial materials to more hydrophobic and larger molecular weight fractions. Bacterial materials developed with humic acid as carbon source contained more hydrophobic and larger molecular weight fractions, hence had higher DBPFP than bacterial materials developed with acetate. DBPs yields of bacterial materials were lower than that of NOMs precursor during chlorination, but during chloramination DBPs yields of bacterial materials were higher. The extracellular polymeric substances (EPS) matrix had higher DBPs yield than biofilm cells. Polysaccharide was more likely to be the main DBPs precursor in the EPS matrix.

Seasonal Determination and Investigation of Disinfection by Product Formation Potentials (DBPFPs) of Surface Waters, İstanbul Ömerli and Büyükçekmece Case Study

All surface and ground waters include natural organic matter (NOM). During the disinfection NOM reacts with chlorine and forms various types of halogenated disinfection by-products (DBPs). There are lots of study in the literature about these possible carcinogenic effects on human. Trihalomethanes (THMs) and haloacetic acids (HAAs) are the most widely known and most produced DBPs. But there lots of different types of DBPs occurred after the disinfection and sometimes absorbable organic halogens (AOX) measurement can be used for determining the total amount of DBPs. In this study raw water samples were taken from Büyükçekmece (BC) and Ömerli (OM) surface water sources in the seasonal basis. At the first stage water quality parameters were analysed and then samples were chlorinated. After 7 days reaction period THMs, HAAs, haloasetonitrilles (HANs), chloral hydrate (CH), chloropicrin (CP) and AOX measurements were conducted and according to these results undefined DBPs percentage of AOX was calculated. In terms of OM and BC raw water undefined portion of AOX was averagely calculated as 59.4% and 58% respectively.

Modelling of THM formation potential and DOM removal based on drinking water catchment characteristics

Catchment properties influence the character and concentration of dissolved organic matter (DOM). Surface and subsurface runoff from discrete catchments were collected and DOM was measured and assessed in terms of its treatability by Enhanced Coagulation and potential for disinfection by-product (trihalomethane, THMFP) formation potential. Models were developed of [1] DOM character [i.e. SUVA and SpCoL] and concentration (measured as dissolved organic carbon), [2] treatability of DOM by coagulation/flocculation processes and [3] specific THMFP based on the catchment features including: (a) surface and sub-surface soil texture (% clay: 5–25%), (b) topography (% slope: 5–15%) and (c) vegetation cover [i.e. high photosynthetic vegetation, low photosynthetic vegetation and bare soil] extracted from RapidEye satellite imagery using spectral mixture analysis. From these models, a catchment management decision support tool was designed for application by catchment managers to support decision-making of land-use and expected water quality related to water resources for drinking water supply. Software and data availabilityData sets used for models developing presented in this paper have been published in Research Data Australia (RDA) under the title of “Impacts of catchment properties on DOM and nutrients in waters from drinking water catchments”.11Link: https://researchdata.ands.org.au/impacts-catchment-properties-water-catchments/932912?source=undefined. These datasets are provided by the University of South Australia (UniSA). All data in these datasets were collected as part of the Australian Research Council project, ARC Linkage-LP110200208. These data sets are available in open access and published in June 2017. A catchment management decision support model (CMDSM) tool was developed. Macros created using Visual Basic for Applications in Excel 2010. Excel 2010 or higher is required to open the CMDSM tool. The tool is provided by the University of South Australia (UniSA) and is not currently available on-line so please contact the corresponding author for access or further information.

Leakage of soluble microbial products from biological activated carbon filtration in drinking water treatment plants and its influence on health risks

The application of ozone-biological activated carbon (O3-BAC) as an advanced treatment method in drinking water treatment plants (DWTPs) can help to remove organic micropollutants and further decrease the dissolved organic carbon (DOC) level in finished water. With the increase attention to microbial safety of drinking water, a pre-positioned O3-BAC followed by a sand filter has been implanted into DWTP located in Shanghai, China to increase the biostability of effluents. The results showed that BAC had high removal efficiencies of UV254, DOC and disinfection by-product formation potential (DBPFP). The removal efficiencies between pre- and post-positioned BAC filtrations were similar. Based on the analyses of fluorescence excitation–emission matrix spectrophotometry (FEEM), the generation and leakage of soluble microbial products (SMPs) were found in both two BAC filtrations on account of the increased fluorescence intensities and fluorescence regional integration (FRI) distribution of protein-like organics, as well as the enhanced biological index (BIX). The leakage of SMPs produced by metabolism of microbes during BAC process resulted in increased DBPFP yield and carcinogenic factor per unit of DOC (CF/DOC). Although BAC filtration reduced the DBPFP and CF, there still was high health risk of effluents for the production of SMPs. Therefore, the health risks for SMPs generated by BAC filtration in drinking water advanced treatment process should be addressed, especially with that at high temperature.

Use of ozone-biofiltration for bulk organic removal and disinfection byproduct mitigation in potable reuse applications

The purpose of this research was to investigate the impacts of ozone dose and empty bed contact time (EBCT) in ozone-biofiltration systems on disinfection byproduct (DBP) formation potential. The data were used to evaluate the possibility of using DBP formation potential as an alternative guideline for total organic carbon (TOC) removal in potable reuse applications. A pilot-scale ozone-biofiltration system was operated with O3/TOC ratios ranging from 0.1 to 2.25 and EBCTs ranging from 2 to 20 min. The biofiltration columns contained anthracite or biological activated carbon (BAC). Bench-scale chlorination was performed using the uniform formation conditions (UFC) approach, and quenched samples were analyzed for total trihalomethanes (TTHMs) and regulated haloacetic acids (HAA5s). The data demonstrated that ozone-biofiltration achieved TOC removals ranging from ∼10 to 30%, depending on operational conditions, but biofiltration without ozone generally achieved <10% TOC removal. UFC testing demonstrated that ozone alone was efficient in transforming bulk organic matter and reducing DBP formation potential by 10–30%. The synergistic combination of ozone and biofiltration achieved average overall reductions in TTHM and HAA5 formation potential of 26% and 51%, respectively. Finally, a maximum TOC concentration of 2.0 mg/L was identified as a recommended treatment target for reliable compliance with TTHM and HAA5 regulations for potable reuse systems in the United States.

Performance of ozonation and biological activated carbon in eliminating sulfonamides and sulfonamide-resistant bacteria: A pilot-scale study

Removal of sulfonamides (SAs) by an integrated ozonation and biological activated carbon filtration (O3-BAC) process, as an advanced drinking water treatment process, was evaluated in a pilot-scale study. Furthermore, the effects of the O3-BAC process on sulfonamide-resistant bacteria (SRB) and on the removal of total organic carbon, UV254, and turbidity were investigated. Results indicate that ozonation could effectively remove SAs from water at an appropriate ozone dose with an improvement of water quality; however, BAC filtration would lead to an increase of SRB. In addition, the performance of the integrated process in eliminating disinfection byproducts formation potential (DBPsFP) in chlorination was evaluated. The results show ozonation would result in an increase of DBPsFP, while subsequent BAC filtration could effectively reduce DBPsFP to the safety-standard level of water quality. Overall, effective removal was achieved by the O3-BAC process in terms of the reduction of SAs but not of SRB. Subsequent disinfection is significant and biological safety should be evaluated further to ensure the effectiveness of the integrated process and the security of water quality.

Ceramic microfiltration; a novel and compact process for the treatment of surface water

Abstract In-line coagulation adsorption (ILCA) followed by ceramic microfiltration (CMF) was tested at pilot scale and compared to a full scale traditional process consisting of coagulation and dissolved air flotation (DAF) followed by rapid gravity sand filtration (RGF), for treating a reservoir water source which is prone to high concentrations of algae. The ILCA CMF process was shown to remove 10–16% more dissolved organic carbon (DOC) and reduced disinfection by-product formation potential (DBPFP) by 9–13% in comparison to conventional treatment (optimised coagulation). ILCA effectively controlled membrane fouling allowing the ceramic membranes to be operated at high flux (200 l/m2h) with low membrane fouling (0.9–1.9 kPa/day). A process comprising ILCA and direct ceramic microfiltration was shown to provide very stable treated water quality under a range of challenging conditions. Additionally, the process is more compact showing significant reductions (circa 60%) in footprint relative to a conventional DAF/RGF process.

The control of disinfection by-products precursors by advanced methods of water treatment

Abstract In the article, the results of the research on reactivity of natural organic matter in regard to disinfection by-products, specifically trihalomethanes (THM) formation, with the use of model waters, are discussed. Additionally, the evaluation of different processes used in water treatment, i.e. photocatalysis, MIEX®DOC and membrane processes, is made. It was found that the affinity of particular natural organic matter compounds to form chlorination by-products could be arranged in a series: hydrophobic fraction (HA) &amp;gt; hydrophilic fraction (FA). The applied treatment processes efficiently decreased the concentration of disinfection by-products (DBPs) precursors and characterized with different removal mechanisms. Water treated by means of photocatalysis (specific potential of ∑THM was 30 μg/mg dissolved organic carbon (DOC) for HA and 12 μg/mg DOC for FA) revealed lower affinity to form chlorination by-products in comparison with water undergone to MIEX®DOC process (specific potential of ∑THM was 38 μg/mg DOC for HA and 29 μg/mg DOC for FA). Moreover, combination of those methods with membrane processes efficiently reduced DBPs formation potential. In nanofiltration effluents DBPs potential were very low and equalled to 50 μg/L for HA and 15 μg/L for FA.

Evaluation of disinfection by-products (DBPs) formation potential in ANAMMOX effluents.

Disinfection by-products (DBPs), major health concerns in the potable reuse of municipal wastewater effluent, are process-related in wastewater treatment systems. Anammox is a promising and increasingly-applied technology for nitrogen removal in wastewater. In this study, the relationship between DBP formation potential and the anammox process has been investigated based on a lab-scale sequencing batch reactor (SBR). Excitation and emission matrix (EEM) fluorescence spectroscopy was employed to identify the compositions of the DBP precursors. The results showed that the effluents from the anammox SBR could yield both carbonaceous and nitrogenous DBPs after chlorination. Trichloromethane (TCM) was the dominant product among all DBPs detected. The anammox effluent has a low specific TCM formation potential of 0.778 μmol/mmol C and a trichloronitromethane (TCNM) formation potential of 0.0725 μmol/mmol C, leading to a TCM and TCNM formation potential ratio of 10.7. We found that substrate utilization of anammox did not enhance DBP yields, and the DBP formation potential decreased after 10 hour starvation. High pH conditions stimulated the production of TCM precursors in the anammox reactor. Humic acid-like and protein-like substances were identified in the EEM spectra of anammox effluents.