40 research outputs found
Formation of iodo-trihalomethanes, iodo-haloacetic acids, and haloacetaldehydes during chlorination and chloramination of iodine containing waters in laboratory controlled reactions
Iodine containing disinfection byproducts (I-DBPs) and haloacetaldehydes (HALs) are emerging disinfection by-product (DBP) classes of concern. The former due to its increased potential toxicity and the latter because it was found to be the third most relevant DBP class in mass in a U.S. nationwide drinking water study. These DBP classes have been scarcely investigated, and this work was performed to further explore their formation in drinking water under chlorination and chloramination scenarios. In order to do this, iodo-trihalomethanes (I-THMs), iodo-haloacetic acids (I-HAAs) and selected HALs (mono-HALs and di-HALs species, including iodoacetaldehyde) were investigated in DBP mixtures generated after chlorination and chloramination of different water matrices containing different levels of bromide and iodide in laboratory controlled reactions. Results confirmed the enhancement of I-DBP formation in the presence of monochloramine. While I-THMs and I-HAAs contributed almost equally to total I-DBP concentrations in chlorinated water, I-THMs contributed the most to total I-DBP levels in the case of chloraminated water. The most abundant and common I-THM species generated were bromochloroiodomethane, dichloroiodomethane, and chlorodiiodomethane. Iodoacetic acid and chloroiodoacetic acid contributed the most to the total I-HAA concentrations measured in the investigated disinfected water. As for the studied HALs, dihalogenated species were the compounds that predominantly formed under both investigated treatments.C.P. acknowledges support from the European Union 7th R&D Framework Programme (FP7/2007-2013) under grant agreement 274379 (Marie Curie IOF) and the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the COFUND Programme of the Marie Curie Actions of the EU’s FP7 (2014 BP_B00064). The EU is not liable for any use that may be made of the information contained therein. This work has been financially supported by the Government of Catalonia (Consolidated Research Groups 2014 SGR 418-Water and Soil Quality Unit and 2014 SGR 291-ICRA).Peer reviewe
Chronic impact of tetracycline on the biodegradation of an organic substrate mixture under anaerobic conditions
The study evaluates the chronic impact of the antibiotic tetracycline on the biodegradation of organic substrate under anaerobic conditions. The experiments involved an anaerobic sequencing batch reactor fed with a synthetic substrate mixture including glucose, starch and volatile fatty acids, and operated in a sequence of different phases with gradually increasing tetracycline doses of 1.65–8.5 mg/L, for more than five months. Tetracycline exerted a terminal/lethal effect at 8.5 mg/L on the microbial community under anaerobic conditions, which caused the inhibition of substrate/COD utilization and biogas generation and leading to a total collapse of the reactor. The microbial activity could not be recovered and re-started within a period of more than 10 days, even after stopping tetracycline dosing. At lower doses, substrate utilization was not affected but a reduction of 10–20% was observed in the biogas/methane generation, suggesting that substrate utilization of tetracycline to the biomass was limiting their bioavailability. During the experiments, tetracycline was partially removed either through biodegradation or conversion into its by-products. The adverse long-term impact was quite variable for fermenting heterotrophic and methanogenic fractions of the microbial community based on changes inflicted on the composition of remaining/residual organic substrate.This study was funded by The Turkish Academy of Sciences (TUBA). It was also this work was partly supported by the Generalitat de Catalunya (Consolidated Research Group: Water and Soil Quality Unit 2009-SGR-965).Peer reviewe
Discovery of Emerging Disinfection by-products in Water using Gas Chromatography coupled with Orbitrap-based Mass Spectrometry
The disinfection of drinking water is required in order to protect consumers from potential waterborne
infectious and parasitic pathogens. Water is commonly treated by adding chemical disinfectants, such
as free chlorine, chloramines, chlorine dioxide, and ozone. However, although very effective in removing
disease-causing microorganisms, these disinfectants can react with naturally occurring materials in the
water and can form disinfection by-products (DBPs) which can be harmful to human health. In particular,
compounds containing an iodo-group, i.e., iodinated DBPs (iodo-DBPs), may pose a greater health risk
for the population exposed to them than their brominated and chlorinated analogues [1]. In recent years,
several chemical classes of low molecular weight iodo-DBPs have been reported; however, many more
may be still present in the unknown fraction (~50%) of halogenated material formed during disinfection
treatments [2]. Therefore, complete characterization of iodo-DBPs present in DBP mixtures is crucial to
further investigate their occurrence in disinfected waters and potential toxicity effects.
The identification of emerging iodinated DBPs in water is difficult due to the complexity of this matrix
and the low concentrations of these compounds. For this, analytical techniques with high resolving
power, high mass accuracy and sensitivity are required. In this work, a novel gas chromatography (GC),
coupled with high-resolution accurate mass Orbitrap mass spectrometer (the Thermo Scientific™ Q
Exactive™ GC hybrid quadrupole-Orbitrap mass spectrometer), has been used for iodo-DBPs detection
and accurate mass identification in chlorinated and chloraminated water samplesC. P. acknowledges support provided by the European Union 7th R&D Framework Programme
(FP7/2007e2013) under grant agreement 274379 (Marie Curie IOF) and the Secretary for Universities
and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the
COFUND programme of the Marie Curie Actions of the EU’s FP7 (2014 BP_B00064). This work has
been financially supported by the Generalitat de Catalunya (Consolidated Research Groups “2014
SGR 418 - Water and Soil Quality Unit” and 392 2014 SGR 291 - ICRA) and by the European Union’s
FP7 for research, technological development and demonstration under grant agreement nº 603437
(SOLUTIONS). The EU is not liable for any use that may be made of the information contained therein.Peer reviewe
Erratum to: Characterization of iodinated disinfection by-products in chlorinated and chloraminated waters using Orbitrap based gas chromatography-mass spectrometry
Recent developments in gas chromatography (GC)-mass spectrometry (MS) have opened up the possibility to use the high resolution-accurate mass (HRAM) Orbitrap mass analyzer to further characterize the volatile and semivolatile fractions of environmental samples. This work describes the utilization of GC Orbitrap MS technology to characterize iodine-containing disinfection by-products (iodo-DBPs) in chlorinated and chloraminated DBP mixture concentrates. These DBP mixtures were generated in lab-scale disinfection reactions using Llobregat river water and solutions containing Nordic Lake natural organic matter (NOM). The DBPs generated were concentrated using XAD resins, and extracts obtained were analyzed in full scan mode with the GC Orbitrap MS. Integration of high resolution accurate mass information and fragment rationalization allowed the characterization of up to 11 different iodo-DBPs in the water extracts analyzed, including one new iodo-DBP reported for the first time. Overall, formation of iodo-DBPs was enhanced during chloramination reactions. As expected, NOM characteristics and iodide and bromide content of the tested waters affected the amount and type of iodo-DBPs generated.Peer reviewe
Characterization of iodinated disinfection by-products in chlorinated and chloraminated waters using Orbitrap based gas chromatography-mass spectrometry
Recent developments in gas chromatography (GC)-mass spectrometry (MS) have opened up the possibility to use the high resolution-accurate mass (HRAM) Orbitrap mass analyzer to further characterize the volatile and semivolatile fractions of environmental samples. This work describes the utilization of GC Orbitrap MS technology to characterize iodine-containing disinfection by-products (iodo-DBPs) in chlorinated and chloraminated DBP mixture concentrates. These DBP mixtures were generated in lab-scale disinfection reactions using Llobregat river water and solutions containing Nordic Lake natural organic matter (NOM). The DBPs generated were concentrated using XAD resins, and extracts obtained were analyzed in full scan mode with the GC Orbitrap MS. Integration of high resolution accurate mass information and fragment rationalization allowed the characterization of up to 11 different iodo-DBPs in the water extracts analyzed, including one new iodo-DBP reported for the first time. Overall, formation of iodo-DBPs was enhanced during chloramination reactions. As expected, NOM characteristics and iodide and bromide content of the tested waters affected the amount and type of iodo-DBPs generated.C.P. acknowledges support provided by the European Union 7th R&D Framework Programme (FP7/2007-2013) under grant agreement 274379 (Marie Curie IOF) and the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia and the COFUND programme of the Marie Curie Actions of the EU’s FP7 (2014 BP_B00064). This work was financially supported by the Government of Catalonia (Consolidated Research Groups “2014 SGR 418 - Water and Soil Quality Unit” and “2014 SGR 291 – ICRA”) and by the EU’s FP7 for research, technological development, and demonstration (grant agreement no. 603437 - SOLUTIONS).Peer reviewe
Light-induced catalytic transformation of ofloxacin by solar Fenton in various water matrices at a pilot plant: Mineralization and characterization of major intermediate products
This work investigated the application of a solar driven advanced oxidation process (solar Fenton), for the degradation of the antibiotic ofloxacin (OFX) in various environmental matrices at a pilot-scale. All experiments were carried out in a compound parabolic collector pilot plant in the presence of doses of H2O2 (2.5mgL-1) and at an initial Fe2+ concentration of 2mgL-1. The water matrices used for the solar Fenton experiments were: demineralized water (DW), simulated natural freshwater (SW), simulated effluent from municipal wastewater treatment plant (SWW) and pre-treated real effluent from municipal wastewater treatment plant (RE) to which OFX had been spiked at 10mgL-1. Dissolved organic carbon removal was found to be dependent on the chemical composition of the water matrix. OFX mineralization was higher in DW (78.1%) than in SW (58.3%) at 12mgL-1 of H2O2 consumption, implying the complexation of iron or the scavenging of hydroxyl radicals by the inorganic ions present in SW. On the other hand, the presence of dissolved organic matter (DOM) in SWW and RE, led to lower mineralization per dose of H2O2 compared to DW and SW. The major transformation products (TPs) formed during the solar Fenton treatment of OFX, were elucidated using liquid chromatography-time of flight-mass spectrometry (LC-ToF-MS). The transformation of OFX proceeded through a defluorination reaction, accompanied by some degree of piperazine and quinolone substituent transformation while a hydroxylation mechanism occurred by attack of the hydroxyl radicals generated during the process leading to the formation of TPs in all the water matrices, seven of which were tentatively identified. The results obtained from the toxicity bioassays indicated that the toxicity originates from the DOM present in RE and its oxidation products formed during the photocatalytic treatment and not from the TPs resulted from the oxidation of OFX. © 2013 The Authors
Abundance and characteristics of microplastic in sewage sludge: A case study of Yangling, Shaanxi province, China
Microplastics (MPs), as a new type of pollution, could result in serious environmental pollution due to its special properties. Meanwhile, the damage of MPs to environment could be reflected by the MPs characteristics in sewage sludge, one of dominant sinks of MPs. Therefore, this study investigated the abundance and characteristics of MPs of sewage sludge derived from Yangling, Shaanxi province. Results showed that among of all detected MPs, the particle size ranged from 8 μm–1 mm, especially 8–400.00 μm, accounting for 97.27%. Moreover, the microplastics were dominantly in the shape of fragment in white. Additionally, 41.18% of the microplastics were identified as PVC, which led to higher risk index in Yangling. Furthermore, human density, human activities, environmental factors, and industrial types were responsible for the different details of microplastics in sewage sludge. Concluded from these results, more attention is supposed to pay on MPs pollution in Yangling zone.The work is partially supported by National Natural Science Foundation of China (Grant No. 42007349), Young Talent fund of University Association for Science and Technology in Shaanxi, China (20200202), Postdoctoral Science Foundation of China (Grant No. 2019M653765) and Shaanxi Province technology innovation guidance special fund project (No. 2018ZKC-190). We are also thankful to all our research group members for their constructive advice and help
Cocaine and other illicit drugs in airborne particulates in urban environments: a reflection of social conduct and population size
Levels of cocaine and other psychoactive substances in atmospheric particulate matter (PM) were determined in urban environments representing distinct social behaviours with regard to drug abuse: night-life, university and residential areas. Three cities (with population > 1 million and 0.82).Peer reviewe