In vitro agonistic and antagonistic endocrine disrupting effects of organic extracts from waste water of different treatment processes

Effluents from wastewater treatment plant （WWTP） have been reported to have a broad spectrum of endocrine disrupting compounds （EDCs）. The majority of studies have focused on the occurrence of estrogenic activity, while ignoring nuclear hormone receptors （NRs） pathways. In the present study, a battery of in vitro yeast bioassays and a cell bioassay, including antagonistic and agonistic effects on estrogen receptor （ER）, androgen receptor （AR）, progesterone receptor （PR）, estrogen- related receptor （ERR） and aryl hydrocarbon receptor （AHR）, were conducted to evaluate the removal efficien- cies of EDCs by different treatment processes of a WWTP located in Beijing. Estrogenic, anti-estrogenic, anti- androgenic, anti-progesteronic, anti-ERR and the activa- tion of AHR activities were detected in samples from all treatment processes and the receiving water. The concen- tration of estrogenic contaminants with estradiol （E2） equivalent concentrations ranged from 0.82 x 10-9 to 3.54 x 10 9g Ee_EQ.L-1. The concentration of anti-estrogenic contaminants with 4-hydroxytamoxifen （4-OHT） equiva- lent concentrations ranged from 1.24 × 10-6 to 2.36 x 10-6 g 4-OHT-EQ.L-1. The concentration of anti-androgenic contaminants ranged from 2.21 x 10-s to 3.52 × 10-6g flutamide-EQ. L-1. The concentration of anti-progesteronic contaminants ranged from 3.15 x 10^-5 to 2.71 x 10^-4g RU486-EQ. L-1. The concentration of anti-ERR contami- nants ranged from 7.09 x 10-5 to 6.50 x 104 g 4-OHT-EQ × L^-10. The concentration of AHR activators ranged from 1.7 × 10-10 to 3.4 × 10^-10g TCDD-EQ-L-1. These processes including secondary clarifier, coagulation, as well as coal and sand filtration could eliminated 67.2% of estrogenic contaminants, 47.0% of anti-estrogenic contaminants, 98.3% of anti-androgenic contaminants, 88.4% of anti- progesteronic contaminants, 65.4% of anti-ERR contami- nants and 46.9% of AHR activators. WWTP effluents contain multiple receptor disruptors may have very complex adverse effects on exposed organisms.     

Upgrade of three municipal wastewater treatment lagoons using a high surface area media

Lagoon-based municipal wastewater treatment plants (WWTPs) are facing difficulties meeting the needs of rapid population growth as well as the more stringent requirements of discharge permits. Three municipal WWTPs were modified using a high surface area media with upgraded fine-bubble aeration systems. Performance data collected showed very promising results in terms of five-day biochemical oxygen demand (BOD₅), ammonia (NH₃) and total suspended solids (TSS) removal. Two-year average ammonia effluents were 4.1 mg·L^-1 for Columbia WWTP, 4 mg·L^-1 for Larchmont WWTP and 2.1 mg·L^-1 for Laurelville WWTP, respectively. Two- year average BOD₅ effluents were 6.8, 4.9 and 2.7 mg·L^-1, and TSS effluents were 15.0, 9.6 and 7.5 mg·L^-1. The systems also showed low fecal coliform (FC) levels in their effluents.     

最大累积率识别中国地表水中邻苯二甲酸酯类关键污染物和复合污染生态风险

邻苯二甲酸酯类物质(phthalic acid esters,PAEs)环境存在量大,研究表明其能对水生生物造成寿命减少、发育不良、细胞受损等负效应.因此,为保护水生生物,我国地表水中PAEs的生态风险需要科学评估.本文利用了风险商法(risk quotient,RQ)、最大累积率法(maximum cumulative ratio,MCR)、联合概率曲线法(joint probability curve,JPC)结合毒性当量的概念构建了三层级生态风险评价体系,借此评估了我国地表水中PAEs的分布情况与生态风险.结果显示,我国地表水中共检出19种PAEs,浓度范围为ND—5616.80μg·L^-1.邻苯二甲酸二(2-乙基)己酯(di(2-ethylhexyl)phthalate,DEHP)和邻苯二甲酸二丁酯(dibutyl phthalate,DBP)环境存在量最高,且DEHP为PAEs风险的主要贡献者.以DEHP为参照物,JPC的结果显示我国PAEs对5%生物造成急性影响的概率为6.25%—24.02%,造成慢性影响的概率为8.05%—27.79%.PAEs对我国水生生态系统,尤其是西北、东北、中部及华东地区存在较高的生态风险.     

Occurrence and removal of selected polycyclic musks in two sewage treatment plants in Xi’an, China

Polycyclic musks are widely used for cosmetics and other personal care and household cleaning products. The occurrence and removal of two representative polycyclic musks, galaxolide (HHCB) and tonalide (AHTN) were investigated in three different processes of two sewage treatment plants (STPs) in Xi’an, China. The samples were preconcentrated by solid phase extraction procedure and analyzed using a gas chromatography mass spectrometry (GC/MS) by a modified procedure. The HHCB was in the range of 82.8 to 182.5 ng·L^-1 in the influents and 22.6 to 103.9 ng·L^-1 in the effluents. The AHTN ranged from 11.0 to 19.3 ng·L^-1 in the influents and 2.2 to 8.8 ng·L^-1 in the effluents. The removal efficiency of the two musks varied in the ranges of 43.1%–70.4% for HHCB and 54.2%–84.4% for AHTN. Concentrations of the two musks in aqueous phase of three processes slightly increased along the primary process, and significantly removed during the biologic treatment processes, revealing that the selected musks could be remarkably removed in varied activated sludge processes. Advanced processes of activated sludge did not show a significant superiority on selected musk removal compared to the conventional process. The selected musk removal mainly resulted from the adsorption function of activated sludge. There was no significant change of HHCB/AHTN ratios along the treatment flow, indicating that each sewage treatment structure had a similar removal efficiency for the two musks.     

A new procedure combining GC-MS with accelerated solvent extraction for the analysis of phthalic acid esters in contaminated soils

An optimized procedure based on gas chromatography-mass spectrometry (GC-MS) combined with accelerated solvent extraction (ASE) is developed for the analysis of six phthalic acid esters (PAEs), which are priority soil pollutants nominated by United States Environmental Protection Agency (USEPA). Quantification of PAEs in soil employs ultrasonic extraction (UE) (USEPA 3550) and ASE (USEPA 3545), followed by clean up procedures involving three different chromatography columns and two combined elution methods. GC-MS conditions under selected ion monitoring (SIM) mode are described and quality assurance and quality control (QA/QC) criteria with high accuracy and sensitivity for target analytes were achieved. Method reliability is assured with the use of an isotopically labeled PAE, di-n-butyl phthalate-d4 (DnBP-D4), as a surrogate, and benzyl benzoate (BB) as an internal standard, and with the analysis of certified reference materials (CRM). QA/QC for the developed procedure was tested in four PAE-spiked soils and one PAE-contaminated soil. The four spiked soils were originated from typical Chinese agricultural fields and the contaminated soil was obtained from an electronic waste dismantling area. Instrument detection limits (IDLs) for the six PAEs ranged 0.10–0.31 μg·L^-1 and method detection limits (MDLs) of the four spiked soils varied from a range of 20–70 μg·kg^-1 to a range of 90– 290 μg·kg^-1. Linearity of response between 20 μg·L^-1 and 2 mg·L^-1 was also established and the correlation coefficients (R) were all>0.998. Spiked soil matrix showed relative recovery rates between 75 and 120% for the six target compounds and about 93% for the surrogate substance. The developed procedure is anticipated to be highly applicable for field surveys of soil PAE pollution in China.     

新型溴系阻燃剂环境污染现状研究进展

新型溴系阻燃剂(NBFRs,novel brominated flame retardants)作为传统溴系阻燃剂的替代品已广泛应用于电子产品、纺织品、家具等商品中,随着这些商品的生产、使用和处置,NBFRs不可避免地释放到环境中,给环境和人体带来潜在的危害.部分NBFRs可通过摄食和呼吸作用进入人体对人体产生一定危害...     

Haloacetic acids in swimming pool and spa water in the United States and China

The objective of this study is to investigate the occurrence of haloacetic acids （HAAs）, a group of disinfection byproducts, in swimming pool and spa water. The samples were collected from six indoor pools, six outdoor pools and three spas in Pennsylvania, the United States, and from five outdoor pools and nine indoor pools in Beijing, China. Five HAAs （HAA5）, including monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid were analyzed. Total chlorine, pH and total organic carbon concentration were analyzed as well. Results indicated that the levels of HAA5 in swimming pools and spas in the United States ranged from 70 to 3980μg·L^-1, with an arithmetic average at 1440μg·L^-1 and a median level at 1150μg·L^-1. These levels are much higher than the levels reported in chlorinated drinking water and are likely due to organic matters released from swimmers＇ bodies. The levels of HAA5 in swimming pools in China ranged from 13 to 332μg·L^-1, with an arithmetic average at 117μg·L^-1 and a median level at 114μg·L^-1. The lower HAA levels in swimming pools in China were due to the lower chlorine residuals. Results from this study can help water professionals to better understand the formation and stability of HAAs in chlorinated water and assess risks associated with exposures to HAAs in swimming pools and spas.     

Evaluate HAA removal in biologically active carbon filters using the ICR database

The effects of biologically active carbon (BAC) filtration on haloacetic acid (HAA) levels in plant effluents and distribution systems were investigated using the United States Environmental Protection Agency’s Information Collection Rule (ICR) database. The results showed that average HAA5 concentrations in all locations were 20.4 μg·L^-1 and 29.6 μg·L^-1 in ICR plants with granular activated carbon (GAC) and ICR plants without GAC process, respectively. For plants without GAC, the highest HAA levels were observed in the quarters of April to June and July to September. However, for plants with GAC, the highest HAA levels were observed in the quarters of April to June and January to March. This HAA level profile inversely correlated well with water temperature, or biologic activity. For GAC plants, simulated distribution samples matched well with distribution system equivalent samples for Cl₃AA and THMs. For plants with and without GAC, simulated distribution samples overestimated readily biodegradable HAAs in distribution systems. The study indicated that through HAA biodegradation, GAC process plays an important role in lowering HAA levels in finished drinking water.     

污水处理厂出水中抗雄激素样化合物控制的优先性研究

污水处理厂出水是环境中内分泌干扰物的重要来源之一。针对关注较少的抗雄激素样内分泌干扰物,在已有研究基础上,依据抗雄激素样化合物的抗雄激素样活性风险,建立了污水处理厂出水中抗雄激素样化合物控制的优先性排序方法。在污水处理厂出水中,共有147种疑似抗雄激素样化合物需要关注,主要为农药类,约占总数的60%。抗雄激素样活性风险排名前10%的化合物如下:邻苯二甲酸二丁酯、邻苯二甲酸二己酯、双酚A、溴螨酯、对叔辛基酚、腐霉利、烯菌酮、氯苯嘧啶醇、烯酰吗啉、杀螟松、十二烷基酚、敌草隆、咯菌酯、2-羟基-4'-甲氧基二苯甲酮、以及邻苯基苯酚。     

Estrogen content and relative performance of Japanese and British sewage treatment plants and their potential impact on endocrine disruption.

Both the UK and Japan are densely populated islands with relatively short rivers. Therefore, both countries are likely to be highly exposed to contaminants emanating from their human populations. This review considered how effective the different sewage treatment facilities of the two countries are at removing steroid estrogens from the effluent. The methods of estrogen analysis in sewage effluent, the number and importance of different sewage treatment types, and their apparent effectiveness at removing estrogens were all considered. In both countries, the activated sludge treatment was dominant in terms of people served and water discharged. The analytical techniques used by those studying estrogen concentrations in effluents in both countries were broadly similar. Activated sludge plant (ASP) effluent in the UK typically contained around 2 ng/L estradiol (E2) and 8 ng/L estrone (E1), while Japanese ASPs typically reported E2 as below detection, and 10 ng/L E1 in their effluents. When estrogenic bioassays were used in Japan, they typically record an estrogenic potency of 10 ng/L E2 equivalents. Even taking into account ethinylestradiol (EE2) (not found in Japanese effluents), the overall estrogenicity of British sewage effluents would appear to be the same as that of Japanese sewage effluents (around 10 ng/L E2 equivalents). This suggests that the ASPs serving the large urban communities in Japan and the UK would have effluent of similar estrogenic potencies. Less information is available about the more numerous biological (trickling) filter plants (BFP) in the UK and oxygen ditches (OD) in Japan which tend to serve smaller, more rural communities. The available data would suggest that the BFPs are significantly less efficient than the ODs at removing E1. This would suggest that in similar circumstances, British headwaters (where this sewage treatment plant (STP) type is often found) might be more at risk from endocrine disruption than their Japanese counterparts. Overall, the apparently higher incidence of endocrine disruption in British wild fish than in Japanese wild fish cannot be attributed to differences in the efficiency of their respective STPs.     

Preparation of hapten-specific monoclonal antibody for cadmium and its ELISA application to aqueous samples

High-affinity and specific monoclonal antibodies against cadmium-ethylene diamine tetraacetic acid (EDTA) complex have been produced using the hybridoma technique. A hapten was synthesized and characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and UV-Vis. Competitive enzyme-linked immunosorbent assay (ELISA) for quantitative detection of cadmium in aqueous sample was developed. The monoclonal antibody with high level of binding affinity for Cd-IEDTA-BSA and high specificity for soluble Cd-EDTA complex showed less than 0.99% cross-reactivity with other 11 metals. The limit of detection was 0.10 μg·L^-1, and the effective linear range was 10^-1–10³ μg·L^-1. The intra- and inter-assay coefficient variations were 1.5%–6.3% and 3.2%–7.4%, respectively. The spike recovery in different water samples were between 98.5% and 110.3%. The detection limit of this assay was well below the allowable concentration of cadmium (3 μg·L^-1), and the working range was wider than that of other methods which showed the range of 2.19–86.38 and 0–10³ μg·L^-1. The competitive ELISA established in this paper was sensitive and accurate in the screening of cadmium in aqueous samples. The results will lay a solid foundation for construction of an immunoassay kit for cadmium.     

Degradation of bisphenol A by microorganisms immobilized on polyvinyl alcohol microspheres

In this study, microorganisms （named B111） were immobilized on polyvinyl alcohol microspheres prepared by the inverse suspension crosslinked method. The biodegradation of bisphenol A （BPA） and 4-hydro- xybenzaldehyde, a degradation product of BPA, by free and immobilized B lll was investigated. The BPA degradation studies were carried out at initial BPA concentrations ranging from 25 to 150 mg·L^-1. The affinity constant Ks and maximum degradation rate Rmax were 98.3 mg·L^-1 and 19.7mg·mg^-1VSS·d^-1 for free B111, as well as 87.2mg·L^-1 and 21.1mg·mg^-1VSS·d^-1 for immobilized B 111, respectively. 16S rDNA gene sequence analyses confirmed that the dominant genera were Pseudomonas and Brevundimonas for BPA biodegradation in microorganisms B 111.     

Abatement of sulfide generation in sewage by glutaraldehyde supplementation and the impact on the activated sludge accordingly

Hydrogen sulfide emission in sewer systems is associated with toxicity, corrosion, odour nuisance and high costs treatment. In this study, a novel method to inhibit sulfide generation from sewage by means of glutaraldehyde supplementation has been suggested and evaluated under anaerobic conditions. Different concentrations of glutaraldehyde at 10, 15, 20, 30 and 40 mg·L^-1 have been investigated. Besides, the possible impacts of glutaraldehyde supplementation on an activated sludge system and an appraisal of the economic aspects are presented as well. As observed from the experimental results, a dosage of 20 mg·L^-1 glutaraldehyde resulted in a significant decrease of the sulfide production by 70%–80% in the simulated sewage. Moreover, the impacts of additional glutaraldehyde at 20 mg·L^-1 on activated sludge, in terms of chemical oxygen demand removal and oxygen uptake rates, were negligible. From an economical point of view, the cost of the commercial glutaraldehyde products required in the operation, which was calculated on the basis of activated sulfide removal avoidance, was around €3.7–4.6 S·kg^-1. Therefore it is suggested that glutaraldehyde supplementation is a feasible technique to abate the sulfide problems in sewer systems. Yet further research is required to elucidate the optimum “booster” dosage and the dosing frequency in situ accordingly.     

Occurrence and fate of antibiotics in advanced wastewater treatment facilities and receiving rivers in Beijing,China

The occurrence and removal of 13 antibiotics were investigated in five wastewater treatment plants （WWTPs） with advanced wastewater treatment processes in Beijing, China. Most of the target antibiotics were detected in the secondary and tertiary effluents, with the concentrations of 4.8-1106.0 and 0.3-505.0ng·L^-1. Fluoroquinolone antibiotics showed relatively high concentrations in all samples （782-1814ng·L^-1）. Different tertiary treatment processes showed discrepant antibiotics removal performances. Ozonation process was found more effective in removing target antibiotics compared to the coagulation-flocculation-sedimentation process and sand filtration process. Investigation of the target antibiotics in three typical urban rivers in Beijing was carried out to understand antibiotics occurrence in surface water environment. Eight antibiotics were detected in the studied rivers, with highest concentration of antibiotics in the fiver which was mainly replenished by reclaimed water. This study showed the necessity of employing more effective advanced treatment facilities to further reduce the discharge amount of antibiotics.     

Selective recovery of Cu2+ and Ni2+ from wastewater using bioelectrochemical system

As the bioelectrochemical system, the microbial fuel cell (MFC) and the microbial electrolysis cell (MEC) were developed to selectively recover Cu²⁺ and Ni²⁺ ions from wastewater. The wastewater was treated in the cathode chambers of the system, in which Cu²⁺ and Ni²⁺ ions were removed by using the MFC and the MEC, respectively. At an initial Cu²⁺ concentration of 500 mg·L^-1, removal efficiencies of Cu²⁺ increased from 97.0%±1.8% to 99.0%±0.3% with the initial Ni²⁺ concentrations from 250 to 1000 mg·L^-1, and maximum power densities increased from 3.1±0.5 to 5.4±0.6 W·m^-3. The Ni²⁺ removal mass in the MEC increased from 6.8±0.2 to 20.5±1.5 mg with the increase of Ni²⁺ concentrations. At an initial Ni²⁺ concentration of 500 mg·L^-1, Cu²⁺ removal efficiencies decreased from 99.1%±0.3% to 74.2%±3.8% with the initial Cu²⁺ concentrations from 250 to 1000 mg·L^-1, and maximum power densities increased from 3.0±0.1 to 6.3±1.2 W·m^-3. Subsequently, the Ni²⁺ removal efficiencies decreased from 96.9%±3.1% to 73.3%±5.4%. The results clearly demonstrated the feasibility of selective recovery of Cu²⁺ and Ni²⁺ from the wastewater using the bioelectrochemical system.     

Phytotoxicity in seven higher plant species exposed to di-n-butyl phthalate or bis (2-ethylhexyl) phthalate

We investigated phytotoxicity in seven plant species exposed to a range of concentrations (0– 500 mg·kg⁻¹ soil) of di-n-butyl phthalate (DnBP) or bis (2-ethylhexyl) phthalate (DEHP), two representative phthalate esters (PAEs) nominated by USEPA as priority pollutants and known environmental estrogens. We studied seed germination, root elongation, seedling growth, biomass (fresh weight, FW) and malondialdehyde (MDA) content of shoots and roots of wheat (Triticum aestivum L.), alfalfa (Medicago sativa L.), perennial ryegrass (Lolium perenne), radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), oat (Avena sativa) and onion (Allium cepa L.), together with monitoring of plant pigment content (chlorophyll a, b and carotinoids) in alfalfa, radish and onion shoots. Root elongation, seedling growth and biomass of the test species were generally inhibited by DnBP but not by DEHP, indicating a lower level of phytotoxicity of DEHP than of DnBP. MDA contents of four species were promoted by PAE exposure, but not in alfalfa, ryegrass or onion shoots, indicating lower sensitivity of these three species to PAE pollutants. Plant pigment contents were clearly affected under the stress of both pollutants, implying the potential damage to the photosynthetic system of test plants, mainly by decreasing the content of chlorophyll a and b. Results of DnBP and DEHP phytotoxicity to the primary growth of test plants has provided information for the assessment of their environmental risk in the soil and also forms a basis for the further analysis of their toxic effects over the whole growth period of different plant species.     

Effects of humic acid on residual Al control in drinking water treatment plants with orthophosphate addition

This study aimed to investigate the effects of humic acid (HA) on residual Al control in drinking water facilities that used orthophosphate addition. The results showed that adding orthophosphate was an effective method for residual Al control for the raw water without HA. When orthophosphate was added at 1.0 min before the addition of poly aluminum chloride (PACl), the concentrations of soluble aluminum (Sol-Al) and total aluminum (Tot-Al) residue were 0.08 and 0.086 mg·L^-1, respectively; both were reduced by 46% compared with the control experiment. The presence of HA would notably increase the residual Al concentration. For the raw water with 5 mg·L^-1 of HA, the concentrations of Sol-Al and Tot-Al increased from 0.136 and 0.174 mg·L^-1 to 0.172 and 0.272 mg·L^-1, respectively. For water with a HA concentration above 5 mg·L^-1, orthophosphate was ineffective in the control of residual Al, though there were still parts of orthophosphate were removed in coagulation. The amounts of Al removal were positively correlated with the solids freshly formed in coagulation. Similar to the raw water without HA, the best Al control was obtained with orthophosphate salt added at 1.0 min before PACl. HA concentrations in the raw water, solution pH, and the orthophosphate dosage suitable for residual Al control by orthophosphate precipitation were also investigated.     

Optimization of thermophilic anaerobic-aerobic treatment system for Palm Oil Mill Effluent (POME)

Optimization of an integrated anaerobic-aerobic bioreactor (IAAB) treatment system for the reduction of organic matter (Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) concentrations) in Palm Oil Mill Effluent (POME) to legal standards with high methane yield was performed for the first time under thermophilic condition (50°C–55°C) by using response surface methodology (RSM). The experiments were conducted based on a central composite rotatable design (CCRD) with three independent operating variables, organic loading rates in anaerobic compartment (OLR_an) and mixed liquor volatile suspended solids (MLVSS) concentration in anaerobic (MLVSS_an) and aerobic compartments (MLVSS_a). The optimum conditions for the POME treatment were determined as OLR_an of 15.6 g COD·L^-1·d^-1, MLVSS_an of 43100 mg·L^-1, and MLVSS_a of 18600 mg·L^-1, where high aerobic COD, BOD and TSS removal efficiencies of 96.3%, 97.9%, and 98.5% were achieved with treated BOD of 56 mg·L^-1 and TSS of 28 mg·L^-1 meeting the discharge standard. This optimization study successfully achieved a reduction of 42% in the BOD concentrations of the final treated effluent at a 48% higher OLR_an as compared to the previous works. Besides, thermophilic IAAB system scores better feasibility and higher effectiveness as compared to the optimized mesophilic system. This is due to its higher ability to handle high OLR with higher overall treatment efficiencies (more than 99.6%), methane yield (0.31 L CH₄·g^-1 COD_removed) and purity of methane (67.5%). Hence, these advantages ascertain the applicability of thermophilic IAAB in the POME treatment or even in other high-strength wastewaters treatment.     

高效液相色谱-串联质谱法同时检测水体中26种药物及个人护理品

通过优化固相萃取条件和高效液相色谱-串联质谱参数,建立了可以同时检测地表水和地下水中26种典型药物及个人护理品(pharmaceuticals and personal care products,PPCPs),包括磺胺类、大环内酯类、喹诺酮类、酰胺醇类、精神类、消炎止痛类以及个人护理品的检测方法.通过将水样pH值调节至7,利用HLB固相萃取柱对水样中PPCPs进行富集,以甲醇和含0.005%甲酸的水溶液作为正离子模式流动相,甲醇和含0.5 mmol·L^-1乙酸铵的水溶液作为负离子模式流动相进行梯度洗脱,采用多反应监测的质谱扫描模式(MRM)分析测定.26种PPCPs的检出限为0.007—1.78 ng·L^-1,定量限为0.02—5.68 ng·L^-1,回收率为52.28%—115.24%.利用该方法检测北京潮白河地表水和地下水中PPCPs的浓度,结果表明,地表水中PPCPs的含量普遍高于地下水,磺胺甲恶唑、舒必利、咖啡因、卡马西平和布洛芬在地表水和地下水中的含量相对较高,检测浓度分别高达147.83、52.48、78.35、166.58、30.63 ng·L^-1.     

Whole pictures of halogenated disinfection byproducts in tap water from China’s cities

When bromide/iodide is present in source water, hypobromous acid/hypoiodous acid will be formed with addition of chlorine, chloramine, or other disinfectants. Hypobromous acid/hypoiodous acid undergoes reactions with natural organic matter in source water to form numerous brominated/iodinated disinfection byproducts (DBPs). In this study, tap water samples were collected from eight cities in China. With the aid of electrospray ionization-triple quadrupole mass spectrometry by setting precursor ion scans of m/z 35, m/z 81, and m/z 126.9, whole pictures of polar chlorinated, brominated, and iodinated DBPs in the tap water samples were revealed for the first time. Numerous polar halogenated DBPs were detected, including haloacetic acids, newly identified halogenated phenols, and many new/unknown halogenated compounds. Total organic chlorine, total organic bromine, and total organic iodine were also measured to indicate the total levels of all chlorinated, brominated, and iodinated DBPs in the tap water samples. The total organic chlorine concentrations ranged from 26.8 to 194.0 μg·L^–1 as Cl, with an average of 109.2 μg·L^–1 as Cl; the total organic bromine concentrations ranged from below detection limit to 113.3 μg·L^–1 as Br, with an average of 34.7 μg·L^–1 as Br; the total organic iodine concentrations ranged from below detection limit to 16.4 μg·L^–1 as I, with an average of 9.1 μg·L^–1 as I; the total organic halogen concentrations ranged from 31.3 to 220.4 μg·L^–1 as Cl, with an average of 127.2 μg·L^–1 as Cl.