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1.
Chemosphere ; 254: 126890, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957290

RESUMO

Chlorine disinfection inactivates pathogens in drinking water, but meanwhile it causes the formation of halogenated disinfection byproducts (DBPs), which may induce adverse health effects. Humans are unavoidably exposed to halogenated DBPs via tap water ingestion. Boiling of tap water has been found to significantly reduce the concentrations of halogenated DBPs. In this study, we found that compared with boiling only, adding ascorbate (vitamin C) or carbonate (baking soda) to tap water and then boiling the water further reduced the level of total organic halogen (a collective parameter for all halogenated DBPs) by up to 36% or 28%, respectively. Adding ascorbate removed the chlorine residual in tap water and thus prevented the formation of more halogenated DBPs in the boiling process. Adding carbonate elevated pH of tap water and consequently enhanced the hydrolysis (dehalogenation) of halogenated DBPs or led to the formation of more trihalomethanes that might volatilize to air during the boiling process. The comparative developmental toxicity of the DBP mixtures in the water samples was also evaluated. The results showed that adding a tiny amount of sodium ascorbate or carbonate (2.5-5.0 mg/L) to tap water followed by boiling for 5 min reduced the developmental toxicity of tap water to a substantially lower level than boiling only. The addition of sodium ascorbate or carbonate to tap water in household could be realized by preparing them in tiny pills. This study suggests simple and effective methods to reduce the adverse effects of halogenated DBPs on humans through tap water ingestion.


Assuntos
Desinfetantes/toxicidade , Poluentes Químicos da Água/toxicidade , Ácido Ascórbico , Carbonatos , Cloro , Desinfetantes/análise , Desinfecção/métodos , Água Potável/química , Halogenação , Halogênios , Humanos , Trialometanos/análise , Volatilização , Poluentes Químicos da Água/análise , Purificação da Água/métodos
2.
Chemosphere ; 258: 127387, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947680

RESUMO

It is well known that serum is an ideal and potential choice to reflect the toxicity of fluoride. However, the effects of fluoride on serum metabolome have not been reported until now. In this study, the models of 3-week-old rats exposed fluoride by breast milk and 11-week-old rats exposed fluoride via breast milk and drinking water containing sodium fluoride (100 mg/L) were established. Using Ultra Performance Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (UPLC-MS/MS), as compared with control group, 28 negative (NEG) and 52 positive (POS) metabolites were significantly up-regulated, meanwhile 30 NEG and 21 POS significantly down-regulated metabolites were found in serum of 3-week-old rats exposed to fluoride. For 11-week-old fluorosis rats, there were 119 NEG and 65 POS metabolites significantly increased, and 7 NEG, 5 POS metabolites were obviously decreased. Importantly, nicotinamide, adenosine, 1-Oleoyl-sn-glycero-3-phosphocholine (OGPC), and 1-Stearoyl-sn-glycerol 3-phosphocholine (SGPC) were shared by two models. The metabolites of urea cycle, such as urea and N2-Acetyl-l-ornithine, betaine as a methyl donor, were regarded to reflect the fluorosis degree. These metabolites could be the potential markers of fluorosis, contributing to the prevention and treatment of fluorosis.


Assuntos
Fluoretos/toxicidade , Metaboloma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Betaína , Cromatografia Líquida , Água Potável/química , Feminino , Humanos , Masculino , Metabolômica , Leite/metabolismo , Ratos , Fluoreto de Sódio , Espectrometria de Massas em Tandem
3.
J Water Health ; 18(4): 602-612, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32833686

RESUMO

Sand dams can be an effective community-scale solution to increasing water supplies in some arid and semi-arid regions, but there are few studies that have investigated water quality at sand dams. This study investigated the levels of coliform bacteria and salt content as parameters of potential concern. Most water taken from sand dam sources had fecal coliforms present. Median fecal coliforms were in the range of 150-800 cfu/100 ml for unprotected sources (scoop holes, surface water or hand dug wells), levels which are considered high or very high health risk. Pump wells had less contamination, with fecal coliforms detected in one-third of samples in the dry season. Despite this contamination, user surveys indicated that 74% of communities generally view water as clean for drinking, and 72% reported that no or few people in their community treat their water. Salt content in the dry season was in the poor or unacceptable range (above 900 ppm as total dissolved solids) in 33% of water samples. Results suggest that fecal coliforms and salt content represent two types of challenges to water quality at sand dams: fecal coliforms are a health hazard, whereas high salt content potentially reduces the amount of usable water that is available.


Assuntos
Água Potável/microbiologia , Salinidade , Microbiologia da Água , Abastecimento de Água/estatística & dados numéricos , Bactérias , Água Potável/química , Fezes , Quênia , Areia
4.
Chemosphere ; 260: 127630, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32758778

RESUMO

Biological treatment processes have the potential to remove organic micropollutants (OMPs) during water treatment. The OMP removal capacity of conventional drinking water treatment processes such as rapid sand filters (RSFs), however, has not been studied in detail. We investigated OMP removal and transformation product (TP) formation in seven full-scale RSFs all treating surface water, using high-resolution mass spectrometry based quantitative suspect and non-target screening (NTS). Additionally, we studied the microbial communities with 16S rRNA gene amplicon sequencing (NGS) in both influent and effluent waters as well as the filter medium, and integrated these data to comprehensively assess the processes that affect OMP removal. In the RSF influent, 9 to 30 of the 127 target OMPs were detected. The removal efficiencies ranged from 0 to 93%. A data-driven workflow was established to monitor TPs, based on the combination of NTS feature intensity profiles between influent and effluent samples and the prediction of biotic TPs. The workflow identified 10 TPs, including molecular structure. Microbial community composition analysis showed similar community composition in the influent and effluent of most RSFs, but different from the filter medium, implying that specific microorganisms proliferate in the RSFs. Some of these are able to perform typical processes in water treatment such as nitrification and iron oxidation. However, there was no clear relationship between OMP removal efficiency and microbial community composition. The innovative combination of quantitative analyses, NTS and NGS allowed to characterize real scale biological water treatments, emphasizing the potential of bio-stimulation applications in drinking water treatment.


Assuntos
Água Potável/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Bélgica , Compostos Férricos , Filtração/métodos , Microbiota , Países Baixos , Nitrificação , RNA Ribossômico 16S/genética , Areia
5.
J Chromatogr A ; 1625: 461337, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709361

RESUMO

Monitoring the levels of perfluorinated compounds (PFCs) in the environment is of vital importance, owing to their sustained environmental presence, extensive distribution, and associated health risks. The development of cost-effective and efficient sorbents for the establishment of sensitive analytical methods is critical for achieving trace-level detection. In this study, a graphitic carbon nitride (g-C3N4)-based sorbent is synthesized by a facile sonication-assisted method exfoliated by zeolitic imidazolate framework-67 (ZIF-67) in situ. The novel ZIF-67/g-C3N4 composites were systematically characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, and N2 adsorption-desorption analysis, exhibiting good dispersity and a large surface area. Moreover, molecular dynamics simulations indicated that g-C3N4 structures can be effectively exfoliated by the introduced ZIF-67 molecules. The hybrid material was successfully utilized as a dispersive solid-phase extraction sorbent, and the extraction factors were systematically optimized by response surface methodology. Under optimal conditions, the synthesized sorbent exhibited desirable linear correlations (R2 > 0.99), a low detection limit (0.3-2 ng L-1), and good repeatability (relative standard deviation <15%, n = 6). The developed method was applied for the analysis of natural and spiked water samples. The study demonstrated that the ZIF-67/g-C3N4 composites are promising materials for pollutant adsorption from drinking water samples.


Assuntos
Água Potável/química , Fluorcarbonetos/análise , Grafite/química , Estruturas Metalorgânicas/química , Compostos de Nitrogênio/química , Extração em Fase Sólida/métodos , Sonicação , Poluentes Químicos da Água/análise , Adsorção , Simulação de Dinâmica Molecular
6.
Chemosphere ; 260: 127579, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32679375

RESUMO

As important emerging contaminants, nonsteroidal anti-inflammatory drugs (NSAIDs) are the most intensively prescribed pharmaceuticals introduced to drinking water due to their incomplete removal in wastewater treatment. While concentrations of NSAIDs in drinking water are generally low, they have been attracting increasing concern as a result of their disinfection byproducts (DBPs) generated in drinking water disinfection. In this work, detection methods were set up for four representative indole-derivative NSAIDs (indomethacin, acemetacin, sulindac, and etodolac) using ultra performance liquid chromatography/electrospray ionization-triple quadruple mass spectrometry (UPLC/ESI-tqMS). ESI+ was better for detection of indomethacin and sulindac, whereas ESI- was suitable to detection of acemetacin and etodolac. With optimized MS parameters, the instrument detection and quantitation limits of the four indole derivatives were achieved to be 1.1-24.6 ng/L and 3.7-41.0 ng/L, respectively. During chlorination, indomethacin and acemetacin could undergo five major reaction types (chlorine substitution, hydrolysis, decarboxylation, C-C coupling, and C-N cleavage) to form a series of DBPs, among which 19 were proposed/identified with structures. Based on the revealed structures of DBPs, transformation pathways of indomethacin and acemetacin in chlorination were partially elucidated. Notably, individual and mixture toxicity of indomethacin and acemetacin before/after chlorination were evaluated using a well-established acute toxicity assessment and a Hep G2 cell cytotoxicity assay, respectively. Results showed that the predicted acute toxicity of a few chlorination DBPs were higher than their precursors; chlorination substantially enhanced the mixture cytotoxicity of indomethacin by over 10 times and slightly increased the mixture cytotoxicity of acemetacin.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/toxicidade , Desinfecção/métodos , Poluentes Químicos da Água/análise , Anti-Inflamatórios não Esteroides/química , Cloro/química , Cromatografia Líquida , Desinfetantes/química , Água Potável/química , Halogenação , Células Hep G2 , Humanos , Indóis/análise , Indóis/química , Indóis/toxicidade , Indometacina/análogos & derivados , Indometacina/análise , Indometacina/química , Indometacina/toxicidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos
7.
PLoS One ; 15(6): e0218698, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32542001

RESUMO

Low-income cities that are subject to high population pressure and vulnerable to climate events often have a low capacity to continuously deliver safe drinking water. Here we reported the results of a 32-year survey on the temporal dynamics of drinking water quality indicators in the city of Antananarivo. We analyzed the long-term evolution of the quality of the water supplied and characterized the interactions between climatic conditions and the full-scale water supply system. A total of 25,467 water samples were collected every week at different points in the supplied drinking water system. Samples were analyzed for total coliforms (TC), Escherichia coli (EC), intestinal Enterococci (IE), and Spores of Sulphite-Reducing Clostridia (SSRC). Nine-hundred-eighty-one samples that were identified as positive for one or more indicators were unevenly distributed over time. The breakpoint method identified four periods when the time series displayed changes in the level and profile of contamination (i) and the monthly pattern of contamination (ii), with more direct effects of rainfall on the quality of supplied drinking water. The modeling showed significantly different lags among indicators of bacteria occurrence after cumulative rainfall, which range from 4 to 8 weeks. Among the effects of low-income urbanization, a rapid demographic transition and the degradation of urban watersheds have gradually affected the quality of the water supplied and resulted in the more direct effects of rainfall events. We focused on the need to adopt an alternative perspective of drinking water and urban watersheds management.


Assuntos
Água Potável , Chuva , Qualidade da Água , Água Potável/química , Água Potável/microbiologia , Madagáscar , Fatores de Tempo , Poluição da Água
8.
Chemosphere ; 259: 127398, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32593818

RESUMO

Arsenic endosmosis causes a severe threat to human health within the developing countries. This study assessed the levels of geogenic arsenic and other heavy metals affecting the release of As in the aquifers within the drinking water sources in Bhojpur district of Bihar, India. Eighteen water samples were collected in triplicates from hand-dug wells in six neighboring villages in proximity to the River Ganga namely Bakhorapur, Gaziapur, Parasrampur (or Kanhachhapara), Saraiya, Paiga and Gundiinin. The physicochemical parameters, ionic content and heavy metal analysis of the collected water samples indicated the region to be highly contaminated with arsenic, zinc, manganese and iron. The arsenic and iron concentration ranged between 24.3 and 168.07 µg/L and 0.17-1.16 mg/L respectively, indicating the excessive withdrawal of groundwater for domestic and irrigation purposes with a significant correlation between both the metals. Elevated concentration of zinc in the region attributed to the excessive application of chemical fertilizers and pesticides. Concentration of manganese was also in the higher range of 0.05-1.15 mg/L, primarily due to the urbanized industrial activities. Human health risk assessment within two population groups in the region indicated that the overall water quality is slightly contaminated but the risk associated with it is low. Water Quality Index ranged from 29 to 48, signifying the water quality to be poor. Residual sodium carbonate values indicated that few water sample sources are not suitable for irrigation purposes whereas, sodium adsorption ratio (SAR) values were within the acceptable limits to be used for irrigation.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Poluentes Químicos da Água/análise , Arsênico/análise , Água Potável/química , Humanos , Índia , Ferro/análise , Manganês/análise , Metais Pesados/análise , Medição de Risco , Rios , Qualidade da Água , Poços de Água
9.
Chemosphere ; 258: 127332, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554009

RESUMO

Prioritizing chemicals posing threats to drinking water resources is crucial for legislation considering the cost of water treatment, remediation, and monitoring. We profiled in vitro potential endocrine disrupting activities (both agonistic and antagonistic) of 18 contaminants most prevalent in Walloon raw water resources intended for drinking water production, including several compound groups: pesticides, perfluorinated compounds, polycyclic aromatic hydrocarbons, a corrosion inhibitor, and bisphenol A. Mixtures thereof relevant for human realistic exposure were also investigated. Seven luciferase reporter gene cell lines were used i.e. three (human and rat) responsive to dioxins through the aryl hydrocarbon receptor (AhR) and four (human) responsive to steroids through the estrogen (ER), androgen (AR), progesterone (PR), and glucocorticoid (GR) receptors. Among the 18 compounds, ten caused at least one response in at least one receptor. Specifically, chlorpyrifos, bisphenol A, fluoranthene, phenanthrene, and benzo [a]pyrene displayed significant activities on several receptors. Bisphenol A agonized ER, but abolished the cells' response to androgen and progesterone. While fluoranthene and phenanthrene strongly reduced human AhR and AR transactivation, benzo [a]pyrene strongly activated AhR and ER, but inhibited GR and AR. In human breast cancer cells, benzo [a]pyrene dramatically activated AhR, inducing a 10-fold higher response than 2,3,7,8-tetrachlorodibenzodioxin (TCDD) at concentrations possibly found realistically in human blood. The mixture of the 18 compounds exerted both ER and rat AhR agonism, with the main contribution being from benzo [a]pyrene or its combination with bisphenol A. Moreover, the mixture significantly inhibited TCDD-induced CYP1A activity (detected only by EROD assays) in human hepatoma cells.


Assuntos
Água Potável/química , Disruptores Endócrinos/análise , Poluentes Químicos da Água/análise , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Compostos Benzidrílicos , Benzo(a)pireno/metabolismo , Estrogênios , Genes Reporter , Humanos , Praguicidas , Fenóis , Dibenzodioxinas Policloradas , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Ratos , Receptores de Hidrocarboneto Arílico/metabolismo , Recursos Hídricos
10.
Chemosphere ; 258: 127370, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554019

RESUMO

Porous luffa plant fibre (LF) was grafted with Fe and Zr, and the ability of the fabricated adsorbents to remove arsenate (As(V)) from water was investigated in batch and column adsorption experiments. The Langmuir adsorption capacity (mg g-1) at pH 7 of LF was found to be 0.035, which increased to 2.55 and 2.89 after being grafted with Fe (FLF-3) and Zr (ZLF-3), respectively. Grafting with Fe and Zr increased the zeta potential and zero point of charge (ZPC) of LF (from pH 3.9 to 7.4 for Fe grafting and to 7.6 for Zr grafting), due to chemical bonding of the metals, possibly with the hydroxyl and carboxylic groups in LF as indicated in FTIR peaks. Zeta potential and ZPC decreased after As adsorption owing to inner-sphere complexation mechanism of adsorption. The increase of pH from 3 to 10 progressively reduced the adsorbents' adsorption capacity. Co-existing anions weakened the As(V) removal efficiency in the order, PO43- > SiO32- > CO32- > SO42-. Adsorption kinetics data fitted well to the Weber and Morris model, which revealed initial fast and subsequent slow rates of intra-particle As diffusion into the bigger pores and smaller pores, respectively. Column adsorption data fitted well to the Thomas model with the predicted adsorption capacities in the same order as in the batch adsorption experiment (ZLF-3 > FLF-3 > LF).


Assuntos
Arseniatos/análise , Água Potável/química , Ferro/química , Luffa/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zircônio/química , Adsorção , Água Potável/normas , Concentração de Íons de Hidrogênio , Cinética
11.
Artigo em Inglês | MEDLINE | ID: mdl-32567990

RESUMO

Surface and groundwater resources in the Seridó Region (Brazilian semiarid) were investigated to evaluate their current quality conditions and suitability for domestic use. The water was characterized in terms of physical, chemical, and radiological parameters; including those required by the Brazilian Drinking Water Quality Standard (DWQS). Information about major and trace elements and radiological aspects of the water are reported for the first time. Salinization was confirmed as a key problem in the region, driven natural and anthropogenic. Overall, water has poor organoleptic characteristics. The concentration of most trace elements was below the recommended level, except for uranium and selenium in groundwater. Gross alpha and beta activities higher than the recommended levels were also recorded in several water samples, mostly from the investigated aquifers. In these samples, a detailed radionuclide analysis is required to estimate the effective dose received by the local population. Overall, the results show that water from the investigated region is not suitable for human consumption unless proper treatment is applied. Water requires proper treatment to decrease the content of dissolved salts, toxic elements, and radionuclides responsible for the high gross alpha and beta activities.


Assuntos
Água Potável , Poluentes Químicos da Água/análise , Poluentes Radioativos da Água/análise , Qualidade da Água , Abastecimento de Água/métodos , Brasil , Água Potável/química , Água Potável/normas , Água Doce/química , Água Subterrânea/química , Humanos , Radioisótopos/análise , Selênio/análise , Oligoelementos/análise , Urânio/análise , Abastecimento de Água/normas
12.
Chemosphere ; 258: 127067, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32544817

RESUMO

Dichloroacetonitrile (DCAN) is one of the emerging nitrogenous disinfection by-products (DBPs) in drinking water. However, its potential toxicological effects remain poorly understood, especially at a low concentration found in the environment. In the present study, we investigated whether the consumption of low-concentration DCAN through drinking water would produce significant effects in male SD rats, with particular focus on their physiological traits and changes in their gut microbiome and metabolite profiles. After a 4-weeks DCAN intervention, significant changes were observed in the body weight, blood indices, and histology in DCAN-treated (100 µg/L) group. Proteobacteria was relatively less abundant in 20 and 100 µg/L DCAN-treated groups compared with that in the control group at phylum level. At genus level, Parasutterella and Anaerotruncus were significantly less abundant in both 20 and 100 µg/L DCAN-treated groups than that in the control group. Furthermore, the gut microbiota-related metabolites were dramatically perturbed after DCAN consumption. In the 20 and 100 µg/L DCAN-treated groups, there were 48 and 95 altered metabolites, respectively, and were found to be involved in sphingolipid signaling pathway, fatty acid biosynthesis, and cGMP-PKG signaling pathway. In summary, we demonstrated that consumption of low-concentration DCAN through drinking water could impair host health and induce gut microbiota dysbiosis and gut microflora-related metabolic disorders in male SD rats. Our findings highlight the potential toxicity of low-concentration DBPs and provide new insight into potential causal relationship between low concentration DBPs found in the drinking water and the host health.


Assuntos
Acetonitrilos/toxicidade , Água Potável , Microbioma Gastrointestinal/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Purificação da Água/métodos , Animais , Análise Química do Sangue , Desinfecção/métodos , Água Potável/efeitos adversos , Água Potável/química , Disbiose/induzido quimicamente , Ácidos Graxos/metabolismo , Microbioma Gastrointestinal/genética , Masculino , Ratos Sprague-Dawley , Esfingolipídeos/metabolismo
13.
Chemosphere ; 251: 126612, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443234

RESUMO

The occurrence of microplastics in drinking water systems has increasingly become a major environmental challenge. Although the potential impacts of microplastics in drinking water on humans are not yet fully understood, microplastics attract the public health concern when they are consumed by humans through drinking water systems. Current drinking water treatment plants constitute an obstacle to the entry of microplastics from raw water into daily drinking water. Therefore, understanding the behaviors of drinking water treatment process and the fates of microplastics in drinking water treatment plants are very important. We systematically reviewed the available knowledge on the global existence of microplastics in raw water, treated water and tap water in this paper. This will offer a new perspective for the threat of microplastics in drinking water to human health and help to formulate effective strategies for microplastic monitoring. The existing knowledge of microplastic removal by different treatment processes was also thoroughly discussed. Additionally, the potential challenges of microplastic removal from treatment processes and remediation strategies of microplastics in drinking water were also put forward. The relationship between the properties and behavior of microplastics during different treatment processes is suggested to explore in the future.


Assuntos
Água Potável/química , Monitoramento Ambiental/métodos , Microplásticos/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água Potável/normas , Humanos
14.
Chemosphere ; 256: 127002, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32445997

RESUMO

Pharmaceuticals and personal care products (PPCPs) has been of concerns for their potential threats to ecosystems and human's health for decades. PPCPs have been detected in water environments worldwide and have been identified in water sources and finished water. To elucidate the potential exposure of PPCPs in drinking water, this study assessed the occurrences and treatment efficiencies of PPCPs in the drinking water of Taiwan. Raw and finished water samples collected from five main drinking water treatment plants (DWTPs) in February, June, and November 2018 were analyzed. Furthermore, laboratory-scale water treatment processes were conducted to evaluate the treatment efficiencies of these chemicals. Most of the water samples from the DWTPs had a low concentration (<30 ng/L) of PPCPs. Only samples from a DWTP was observed to have higher concentration of ibuprofen (55.6 ng/L), benzophenone (92.5 ng/L), caffeine (390.5 ng/L), and diethyltoluamide (DEET) (434.9 ng/L) in raw water than others. The results of laboratory simulations indicated that the pre-chlorination process was the key step responsible for the removal of PPCPs in conventional water treatment processes, which can remove most of the hormone treatment products, parabens, oxybenzone, and acetaminophen in water sources. However, the filtration process with anthracite as a medium could remove some of the parabens (approximately 11.9%-41.2%), hormones (approximately 18.2%-44.8%), suntan lotions (37.5%-68.8%), and naproxen (30.1%) from Milli-Q water. The removal efficiencies of the aforementioned chemicals were marginally lower in raw water. However, analgesics, caffeine, and DEET cannot be removed effectively through conventional drinking water treatment.


Assuntos
Cosméticos/análise , Água Potável/química , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Benzofenonas , Ecossistema , Humanos , Preparações Farmacêuticas/análise , Taiwan , Purificação da Água/métodos
15.
Chemosphere ; 256: 127115, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32454354

RESUMO

The present study focuses on the determination of the occurrence and levels of per- and polyfluoroalkyl substances (PFASs) in the drinking and source water from the Philippines and Thailand. A total of 46 samples (18 commercial bottled waters, 5 drinking water from vending machine (re-fill stations) and 23 source water) were analyzed using liquid chromatography with tandem high-resolution mass spectrometry. Using the targeted method, 12 different PFASs were detected in the drinking water samples with total quantifiable PFASs (∑PFASs) levels ranging from 7.16 to 59.49 ng/L; 15 PFASs were detected in source water with ∑PFASs ranging from 15.55 to 65.65 ng/L. A 100% detection frequency was observed for perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorosulfonic acid (PFOS) in all water samples. Six other PFASs, not included in the targeted analysis, were detected using the suspect screening approach. For the first time, the presence of 2-(N-methylperfluorooctanesulfonamido) acetic acid (N-MeFOSAA) in drinking water is reported, and 3 novel PFASs (C5H5OF8, C6H4O2F6, and C9H2O2F16) were detected using suspect screening in source water. Combined results from target and suspect screening analysis showed that PFASs detected were predominantly (52%) short-chain (with fluorinated alkyl chain of ≤6) which could be explained by their high mobility in the environment. The detected PFASs levels in drinking water will not likely pose immediate health risk to consumers according to US EPA health advisory for PFOS and PFOA of 70 ng/L, but inclusion of bottled and drinking water from re-fill stations in monitoring programs is warranted.


Assuntos
Ácidos Alcanossulfônicos/análise , Caprilatos/análise , Água Potável/química , Monitoramento Ambiental/métodos , Fluorcarbonetos/análise , Água Doce/química , Poluentes Químicos da Água/análise , Cromatografia Líquida , Filipinas , Prevalência , Espectrometria de Massas em Tandem , Tailândia
16.
Chemosphere ; 256: 127136, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32460164

RESUMO

Semi-volatile organic compounds (SVOCs) are ubiquitous and toxic environmental pollutants, and have recently attracted much research attention. However, their occurrence in tapwater and the associated potential health risks have not been thoroughly studied. This work examined 26 household tapwater samples collected in 26 Chinese cities during August and September 2019. Concentrations of 79 SVOCs, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polychlorobenzenes (CBs), were determined using an emerging method of high throughput organic analysis testing combined with high volume solid phase extraction (Hi-throat/Hi-volume SPE). Total concentrations of PAHs, PCBs, OCPs, and CBs were in the ranges 8.70-103 ng L-1 (average 42.1 ng L-1), 61.6-434 pg L-1 (average 274 pg L-1), 13.1-266 pg L-1 (average 59.8 pg L-1), and 3.5-83.0 pg L-1 (average 13.8 pg L-1), respectively. PAHs were the dominant SVOCs, with concentrations 10-100 times those of PCBs, OCPs, and CBs. All the studied SVOCs had concentrations deemed acceptable by Chinese national tapwater standards. These measured SVOCs displayed little spatial variation across China, but were significantly correlated with the size of the economy and population of each city. The human non-carcinogenic and carcinogenic risks associated with the studied SVOCs in Chinese tapwater are negligible.


Assuntos
Água Potável/química , Monitoramento Ambiental/métodos , Compostos Orgânicos Voláteis/análise , Poluentes Químicos da Água/análise , China , Cidades , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Extração em Fase Sólida/métodos
17.
Chemosphere ; 252: 126611, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443275

RESUMO

Halogenated disinfection byproducts (DBPs) are formed during chlorine disinfection of drinking water. The complicated natural organic matter in source water causes the formation of an even more complicated mixture of DBPs. To evaluate the toxicity of a DBP mixture in a disinfected water sample, the sample needs to be pretreated in order to attain an observable acute adverse effect in the toxicity test. During sample pretreatment, volatile DBPs including trihalomethanes, haloacetonitriles and haloketones may be lost, which could affect the toxicity evaluation of the DBP mixture. In this study, we intentionally prepared "concentrated" simulated drinking water samples, which contained sufficiently high levels of volatile and nonvolatile DBPs and thus enabled directly evaluating the toxicity of the DBP mixtures without sample pretreatment. Specifically, the natural organic matter and bromide concentrations and the chlorine dose in the concentrated water samples were 250 times higher than those in a typical drinking water sample. Each concentrated water sample was divided into two aliquots, and one of them was nitrogen sparged to eliminate volatile DBPs; then, both aliquots were used directly in a well-established developmental toxicity test. No significant difference (p > 0.10) was found between the developmental toxicity indexes of each concentrated water sample without and with nitrogen sparging, indicating that the contribution of volatile DBPs to the developmental toxicity of the DBP mixture might be marginal. A reasonable interpretation is that nonvolatile halogenated DBPs (especially the aromatic ones) in the DBP mixture could be the major developmental toxicity contributor that warrants more attention.


Assuntos
Desinfetantes/toxicidade , Água Potável/química , Poluentes Químicos da Água/toxicidade , Animais , Brometos , Cloro , Desinfetantes/análise , Desinfecção , Halogenação , Nitrogênio , Poliquetos/fisiologia , Trialometanos/análise , Poluentes Químicos da Água/análise , Purificação da Água
18.
Chemosphere ; 251: 126388, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443223

RESUMO

Over the last few decades, the global pollution of surface and groundwater poses a serious threat not only to human beings but also towards aquatic lives due to the presence of emerging contaminants. Among the others, the presence of arsenic, fluoride, and iron are considered as the most common toxic pollutants in water bodies. The emergence of metal organic frameworks (MOFs) with high porosity and surface area is represented as significant inclusion into the era of entrapping contaminants present in drinking water. In the present review article, an in-depth insight is provided on the recent developments in the removal of arsenic, fluoride, and iron from drinking water using MOFs. Various aspects related to the synthesis, latest technologies adopted for the modifications in the synthesis process and advanced applications of MOFs for the removal of such contaminants are explicitly discussed. A detailed insight was provided to understand the mechanism of various interactions of MOFs with arsenic and fluoride. With respect to arsenic, fluoride, and iron removal the ultrastructural morphology of MOFs is assessed based on different molecular arrangements. Further, commercial aspects of various MOFs are presented in order to highlight the process feasibility. Finally, various perspectives and challenges involved in process scale up are comprehensively narrated with an aspiration of futuristic developments. The paper will be beneficial to the readers for acquiring a piece of in-depth knowledge on MOFs and its various synthesis approaches along with remarkable achievements for the removal of arsenic, fluoride, and iron from contaminated drinking water.


Assuntos
Arsênico/química , Água Potável/química , Fluoretos/química , Ferro/química , Poluentes Químicos da Água/química , Arsênico/análise , Poluentes Ambientais , Água Subterrânea/química , Humanos , Ferro/análise , Estruturas Metalorgânicas , Poluentes Químicos da Água/análise , Poluição da Água , Purificação da Água/métodos
19.
J Chromatogr A ; 1621: 461090, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32360059

RESUMO

This study evaluates the applicability of a method based on the direct injection of a large volume of water samples to identify and quantify 34 priority and emerging substances, most of them discussed in Directive 2013/39/EU on priority substances in the field of water policy, and Decision 2018/840/EU (Watch List). The method directly injects 500 µL of filtered water sample and so does not use a pre-concentration step. The method was satisfactorily validated for influent and effluent water from a drinking water treatment plant, at three concentrations (1, 10 and 100 ng L-1) with precision and accuracies in the range 1-17% and 71-122% respectively. Sensitivity was good with detection limits in the range 0.15-10 ng L-1 and complied with EU limits in all cases except for estrone, 17-ß-estradiol and 17-α-ethinylestradiol. For these hormones, an on-line solid phase extraction was developed and evaluated. The methods were applied to the analysis of water collected at the influent and effluent of a drinking water treatment plant and revealed the presence of 18 of the target compounds in the influent water and 8 in the effluent water. This showed that most the compounds had been efficiently removed by the processes of the drinking water treatment plant.


Assuntos
Cromatografia Líquida/métodos , Água Potável/química , Espectrometria de Massas em Tandem/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água , Limite de Detecção , Extração em Fase Sólida
20.
J Chromatogr A ; 1622: 461102, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32389418

RESUMO

With the advent of highly selective analysis techniques (e.g., liquid chromatography-tandem mass spectrometry), and lower limits of detection requirements, extraction efficiency is arguably the most important property of modern sample preparation techniques. In this study, the extraction efficiency of Ice Concentration Linked with Extractive Stirrer (ICECLES) was compared to Stir Bar Sorptive Extraction (SBSE) and Solid-Phase Microextraction (SPME). A direct comparison of these sample preparation techniques was carried out with analysis via both Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS) and Thermal Desorption Gas Chromatography - Mass Spectrometry (TD-GC-MS). ICECLES produced 2x and 7x greater TD-GC-MS signals than SBSE and SPME, respectively. When comparing extraction techniques for a suite of 60 pesticides in drinking water, 32, 25, and 13 pesticides were detected via LC-MS/MS at 0.1 ng/mL by ICECLES, SBSE, and SPME, respectively. Overall, ICECLES consistently produced better extraction efficiencies than the other extraction techniques evaluated.


Assuntos
Água Potável/química , Praguicidas/análise , Praguicidas/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Gelo , Microextração em Fase Sólida , Espectrometria de Massas em Tandem
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