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1.
Sci Total Environ ; 927: 172296, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588732

RESUMO

Constructed wetlands (CWs) are pivotal for wastewater treatment due to their high efficiency and numerous advantages. The impact of plant species and diversity on greenhouse gas (GHG) emissions from CWs requires a more comprehensive evaluation. Moreover, controversial perspectives persist about whether CWs function as carbon sinks or sources. In this study, horizontal subsurface flow (HSSF) CWs vegetated with Cyperus alternifolius, Typhae latifolia, Acorus calamus, and the mixture of these three species were constructed to evaluate pollutant removal efficiencies and GHG emissions, and estimate carbon budgets. Polyculture CWs can stably remove COD (86.79 %), NH4+-N (97.41 %), NO3--N (98.55 %), and TP (98.48 %). They also mitigated global warming potential (GWP) by suppressing N2O emissions compared with monoculture CWs. The highest abundance of the Pseudogulbenkiania genus, crucial for denitrification, was observed in polyculture CWs, indicating that denitrification dominated in nitrogen removal. While the highest nosZ copy numbers were observed in CWs vegetated with Cyperus alternifolius, suggesting its facilitation of denitrification-related microbes. Selecting Cyperus alternifolius to increase species diversity is proposed for simultaneously maintaining the water purification capacity and reducing GHG emissions. Carbon budget estimations revealed that all four types of HSSF CWs were carbon sinks after six months of operation, with carbon accumulation capacity of 4.90 ± 1.50 (Cyperus alternifolius), 3.31 ± 2.01 (Typhae latifola), 1.78 ± 1.30 (Acorus calamus), and 2.12 ± 0.88 (polyculture) kg C/m2/yr. This study implies that under these operation conditions, CWs function as carbon sinks rather than sources, aligning with carbon peak and neutrality objectives and presenting significant potential for carbon reduction efforts.


Assuntos
Gases de Efeito Estufa , Eliminação de Resíduos Líquidos , Áreas Alagadas , Gases de Efeito Estufa/análise , Eliminação de Resíduos Líquidos/métodos , Cyperus/metabolismo , Carbono/metabolismo , Águas Residuárias , Typhaceae/metabolismo , Acorus/metabolismo
2.
Org Lett ; 26(8): 1683-1687, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363953

RESUMO

Thiosulfonylation and selenosulfonylation of vinyl azides with thiosulfonates and selenosulfonates were achieved using Cu(dap)2Cl as a photosensitizer under visible-light irradiation. This reaction is the application of a vinyl azide substrate in a group transfer radical addition (GTRA) reaction, through ß-difunctionalization, to obtain a variety of unsymmetric difunctionalized N-unprotected enamines.

3.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38069226

RESUMO

Zelkova schneideriana is a fast-growing tree species endemic to China. Recent surveys and reports have highlighted a continued decline in its natural populations; therefore, it is included in the Red List of Threatened Species by The International Union for Conservation of Nature. A new variety "HenTianGao" (H) has been developed with smaller plant height, slow growth, and lower branching points. In this study, we attempted to understand the differences in plant height of Z. schneideriana (J) and its dwarf variety H. We determined the endogenous hormone content in the annual grafted branches of both J and H. J exhibited higher gibberellic acid (GA)-19 and trans-Zeatin (tZ) levels, whereas H had higher levels of indole-3-acetic acid (IAA) catabolite 2-oxindole-3-acetic acid (OxIAA), IAA-Glu conjugate, and jasmonic acid (JA) (and its conjugate JA-Ile). The transcriptome comparison showed differential regulation of 20,944 genes enriched in growth and development, signaling, and metabolism-related pathways. The results show that the differential phytohormone level (IAA, JA, tZ, and GA) was consistent with the expression of the genes associated with their biosynthesis. The differences in relative OxIAA, IAA-Glu, GA19, trans-Zeatin, JA, and JA-Ile levels were linked to changes in respective signaling-related genes. We also observed significant differences in the expression of cell size, number, proliferation, cell wall biosynthesis, and remodeling-related genes in J and H. The differences in relative endogenous hormone levels, expression of biosynthesis, and signaling genes provide a theoretical basis for understanding the plant height differences in Z. schneideriana.


Assuntos
Reguladores de Crescimento de Plantas , Zeatina , Reguladores de Crescimento de Plantas/metabolismo , Transcriptoma , Ácidos Indolacéticos/metabolismo , Hormônios , Ulmaceae/metabolismo , Regulação da Expressão Gênica de Plantas
4.
Org Lett ; 25(46): 8258-8262, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37955358

RESUMO

A photocatalyzed oxidative dehydrogenative annulation between 2-(1H-indol-2-yl)phenols and alkenylphenols is presented. Various indole-fused benzoxepines can be obtained at room temperature using atom-efficient strategies. This method not only avoids the use of stoichiometric amounts of oxidants but also exhibits excellent atom economy by generating H2O as the only theoretical byproduct.

5.
Chem Sci ; 14(41): 11566-11572, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37886085

RESUMO

Visible-light-promoted site-selective and direct C-F bond functionalization of polyfluorinated iminosulfides was accomplished with alkenes and water under redox-neutral conditions, affording a diverse array of γ-lactams with a fluoro- and perfluoroalkyl-substituted carbon centre. A variety of perfluoroalkyl units, including C2F5, C3F7, C4F9, and C5F11 underwent site-selective defluorofunctionalization. This protocol allows high chemoselectivity control and shows excellent functional group tolerance. Mechanistic studies reveal that the remarkable changes of the electron geometries during the defluorination widen the redox window between the substrates and the products and ensure the chemoselectivity of single C(sp3)-F bond cleavage.

6.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769315

RESUMO

Butanol dehydrogenase (BDH) plays a significant role in the biosynthesis of butanol in bacteria by catalyzing butanal conversion to butanol at the expense of the NAD(P)H cofactor. BDH is an attractive enzyme for industrial application in butanol production; however, its molecular function remains largely uncharacterized. In this study, we found that Fusobacterium nucleatum YqdH (FnYqdH) converts aldehyde into alcohol by utilizing NAD(P)H, with broad substrate specificity toward aldehydes but not alcohols. An in vitro metal ion substitution experiment showed that FnYqdH has higher enzyme activity in the presence of Co2+. Crystal structures of FnYqdH, in its apo and complexed forms (with NAD and Co2+), were determined at 1.98 and 2.72 Å resolution, respectively. The crystal structure of apo- and cofactor-binding states of FnYqdH showed an open conformation between the nucleotide binding and catalytic domain. Key residues involved in the catalytic and cofactor-binding sites of FnYqdH were identified by mutagenesis and microscale thermophoresis assays. The structural conformation and preferred optimal metal ion of FnYqdH differed from that of TmBDH (homolog protein of FnYqdH). Overall, we proposed an alternative model for putative proton relay in FnYqdH, thereby providing better insight into the molecular function of BDH.


Assuntos
Fusobacterium nucleatum , NAD , Fusobacterium nucleatum/metabolismo , NAD/metabolismo , Oxirredutases do Álcool/metabolismo , Álcoois , Butanóis , 1-Butanol , Especificidade por Substrato , Cristalografia por Raios X , Álcool Desidrogenase/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-36613156

RESUMO

Pandemics such as COVID-19 pose serious threats to public health and disrupt the established systems for obtaining healthcare services. Mobile health (mHealth) apps serve the general public as a potential method for coping with these exogenous challenges. However, prior research has rarely discussed the antecedents and effects of mHealth apps and their use as a coping method during pandemics. Based on the technology acceptance model, empowerment theory, and event theory, we developed a research model to examine the antecedents (technology characteristics and event strength) and effects (psychological empowerment) of mHealth apps and their use. We tested this research model through a sequential mixed-method investigation. First, a quantitative study based on 402 Chinese mHealth users who used the apps during the COVID-19 pandemic was conducted to validate the theoretical model. A follow-up qualitative study of 191 online articles and reviews on mHealth during the COVID-19 pandemic was conducted to cross-validate the results and explain the unsupported findings of the quantitative study. The results show that (1) the mHealth app characteristics (perceived usefulness and perceived ease of use) positively affect mHealth app use; (2) mHealth app use positively affects the psychological empowerment of mHealth users; and (3) the characteristics of pandemic events (event criticality and event disruption) have positive moderating effects on the relationship between mHealth app characteristics and mHealth app use. This study explains the role of mHealth apps in the COVID-19 pandemic on the micro-level, which has implications for the ways in which mHealth apps are used in response to public pandemics.


Assuntos
COVID-19 , Aplicativos Móveis , Telemedicina , Humanos , COVID-19/epidemiologia , Pandemias , Telemedicina/métodos , Confidencialidade
8.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675166

RESUMO

Fusobacterium nucleatum is a lesion-associated obligate anaerobic pathogen of destructive periodontal disease; it is also implicated in the progression and severity of colorectal cancer. Four genes (FN0625, FN1055, FN1220, and FN1419) of F. nucleatum are involved in producing hydrogen sulfide (H2S), which plays an essential role against oxidative stress. The molecular functions of Fn1419 are known, but their mechanisms remain unclear. We determined the crystal structure of Fn1419 at 2.5 Å, showing the unique conformation of the PLP-binding site when compared with L-methionine γ-lyase (MGL) proteins. Inhibitor screening for Fn1419 with L-cysteine showed that two natural compounds, gallic acid and dihydromyricetin, selectively inhibit the H2S production of Fn1419. The chemicals of gallic acid, dihydromyricetin, and its analogs containing trihydroxybenzene, were potentially responsible for the enzyme-inhibiting activity on Fn1419. Molecular docking and mutational analyses suggested that Gly112, Pro159, Val337, and Arg373 are involved in gallic acid binding and positioned close to the substrate and pyridoxal-5'-phosphate-binding site. Gallic acid has little effect on the other H2S-producing enzymes (Fn1220 and Fn1055). Overall, we proposed a molecular mechanism underlying the action of Fn1419 from F. nucleatum and found a new lead compound for inhibitor development.


Assuntos
Fusobacterium nucleatum , Sulfeto de Hidrogênio , Fusobacterium nucleatum/metabolismo , Simulação de Acoplamento Molecular , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo
9.
Curr Res Food Sci ; 5: 1205-1215, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992630

RESUMO

Yunnan Province is the major coffee cultivation region in China, and coffee beans produced in Yunnan account for approximately 99% of the total national coffee production. So far, the sensory properties of Yunnan coffee have not been subjected to descriptive analysis. Here, we selected 25 representative coffee bean samples that are produced in different cultivation areas of Yunnan and with different degrees of roasting. A total of 57 sensory descriptors have been associated with the samples, and a sensory wheel that summarizes the sensory characteristics was developed. In addition, to identify the major attributes associated with Yunnan coffee, principal component analysis was performed, and we also explored how the bean origin and degree of roasting are related to the overall sensory features of Yunnan coffee. Our results show that the growing area is an affecting factor on the aspects of "spices", "roasted", "sweet" and "chemical/stale", whereas "mouthfeel" and "roasted", and "sour/acid" levels can be influenced by the degree of roasting. The present sensory characterization may provide valuable information for future improvements of Yunnan's coffee agriculture.

10.
Cancers (Basel) ; 14(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35454837

RESUMO

The macrophage checkpoint interaction CD47-SIRPα is an emerging target for cancer therapy, but clinical trials of monoclonal anti-CD47 show efficacy only in liquid tumors when combined with tumor-opsonizing IgG. Here, in challenging metastatic solid tumors, CD47 deletion shows no effect on tumor growth unless combined with otherwise ineffective tumor-opsonization, and we likewise show wild-type metastases are suppressed by SIRPα-blocked macrophages plus tumor-opsonization. Lung tumor nodules of syngeneic B16F10 melanoma cells with CD47 deletion show opsonization drives macrophage phagocytosis of B16F10s, consistent with growth versus phagocytosis calculus for exponential suppression of cancer. Wild-type CD47 levels on metastases in lungs of immunocompetent mice and on human metastases in livers of immunodeficient mice show that systemic injection of antibody-engineered macrophages also suppresses growth. Such in vivo functionality can be modulated by particle pre-loading of the macrophages. Thus, even though CD47-SIRPα disruption and tumor-opsonizing IgG are separately ineffective against established metastatic solid tumors, their combination in molecular and cellular therapies prolongs survival.

11.
BMC Surg ; 22(1): 103, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35313836

RESUMO

OBJECTIVE: Most hepatocellular carcinoma (HCC) patients in China have some degree of liver cirrhosis. The effect of cirrhosis on the long-term prognosis of HCC patients after hepatectomy is still unclear. This study aimed to investigate the effect of liver cirrhosis on the prognosis of HCC patients after hepatectomy. METHODS: Data from patients who underwent hepatectomy and had pathologically confirmed HCC were retrospectively collected. The patients' clinical pathological data were recorded. Propensity score matching (PSM) was used to eliminate the influence of potential confounding factors. The Kaplan-Meier method was used to calculate the recurrence-free survival (RFS) and overall survival (OS) rates, and Cox regression analysis was used to screen for independent risk factors affecting OS and RFS. RESULTS: A total of 1381 HCC patients who were initially treated with hepatectomy were included, including 797 patients with liver cirrhosis. The RFS and OS rates in the group with cirrhosis were significantly lower than those in the group without cirrhosis (after PSM, RFS: P < 0.001; OS: P = 0.001). Subgroup analysis showed that among patients with Barcelona Clinic Liver Cancer (BCLC) stage 0-B disease, RFS and OS were significantly lower in those with cirrhosis than in those without cirrhosis (both P < 0.05); while in patients with stage C disease, there was no significant difference between those with and without cirrhosis. In the group with cirrhosis, alpha-fetoprotein (AFP) > 400, intraoperative blood loss, tumor diameter > 5 cm, satellite lesions, and large vessel invasion were independent risk factors for RFS, while albumin-bilirubin (ALBI) grade, neutrophil-to-lymphocyte ratio (NLR), tumor diameter > 5 cm, satellite lesions, microvascular invasion, and macrovascular invasion were independent risk factors for OS. CONCLUSION: HCC with liver cirrhosis has specific characteristics. Compared with patients without cirrhosis, patients with cirrhosis have worse long-term survival after surgery. In addition, the independent risk factors for RFS and OS are different between patients with cirrhosis and without cirrhosis; liver cirrhosis is an independent risk factor for the long-term prognosis of HCC patients, especially patients with BCLC stage 0-B disease after hepatectomy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Pontuação de Propensão , Estudos Retrospectivos , Análise de Sobrevida
12.
J Gastrointest Oncol ; 12(2): 819-830, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34012669

RESUMO

BACKGROUND: Microvascular invasion (MVI) is an independent risk factor associated with tumor recurrence and poor survival in patients with intrahepatic cholangiocarcinoma (ICC) after partial hepatectomy (PH). The potential impact of adjuvant TACE on the prognosis of patients with ICC involving MVI (ICC-MVI) remains uncertain. Our aim was to investigate the effectiveness of postoperative adjuvant transarterial chemoembolization (TACE) on ICC involving MVI. METHODS: Multicentric data consisted of 223 patients who underwent curative-intent PH for ICC-MVI from 2002-2015 were retrospectively analyzed. The impact of adjuvant TACE was evaluated using inverse probability of treatment weighting (IPTW) and propensity-score matched (PSM) analyses. RESULTS: No association between the TACE and the overall survival (OS) and recurrence rates was observed among the overall ICC-MVI patients. However, subgroup analyses revealed that adjuvant TACE favored OS (HR, 0.62; 95% CI, 0.39-0.99; P=0.047) and time to recurrence (TTR) (HR, 0.59; 95% CI, 0.36-0.97; P=0.037) among patients with elevated CA19-9 and those without lymphadenectomy (HR, 0.53; 95% CI, 0.30-0.93; P=0.027 for OS, and HR, 0.49; 95% CI, 0.28-0.87; P=0.015 for TTR, respectively). In the CA19-9 ≥39 U/L subgroup and Nx subgroup, adjuvant TACE was associated with higher 1-, 3-, and 5-year OS rates (P=0.033 and P=0.034, respectively) and lower corresponding recurrence rates (P=0.024 and P=0.023, respectively). CONCLUSIONS: Among the ICC-MVI patients undergoing curative-intent PH, only those have elevated CA19-9 or who did not undergo lymphadenectomy might be suitable for adjuvant TACE.

13.
J Org Chem ; 86(7): 5274-5283, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33709711

RESUMO

We describe a mild and broadly applicable protocol for the preparation of a diverse array of multisubstituted α-selenoenals and -enones from readily accessible propargylic alcohols and diselenides. The transformation proceeds via the Selectfluor-promoted selenirenium pathway, which enables selenenylation/rearrangement of a variety of propargylic alcohols. Gram-scale experiments showed the potential of this synergistic protocol for practical application.

14.
J Chromatogr Sci ; 59(3): 217-222, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33275658

RESUMO

An ion chromatography (IC) system with switching recycling column was developed for the determination of bromate in drinking water with high chloride content. The system included a pump, two switching valves, guard column and analytical column, suppressor and a conductivity detector. In this method, the single eluent was used for both online collection and matrix elimination, and bromate was eluted from the concentrator column to the analytical column circularly. Under the optimized separation conditions, the method showed good linearity (r = 0.9995) in the range of 1-100 µg/L and repeatability (RSD ≤ 4.80%, n = 6). The limit of detection was 0.2 µg/L (S/N = 3) with 1000 µL sample volume injections. The method was applied to analysis of drinking and tap waters, and satisfactory recoveries of spiked samples between 96.8% and 108.7% were obtained. The result showed that the recycling column-switching system can be useful for the determination of traces of bromate in high-chloride samples, which is required in production of the drinking water and quality control of the final product.


Assuntos
Bromatos/análise , Cromatografia por Troca Iônica/métodos , Água Potável/química , Cloretos/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
15.
Plant Physiol Biochem ; 155: 938-951, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32961471

RESUMO

Michelia crassipes is the only plant with purple flowers amongst Michelia species, and its tepals exhibit an obvious color change from green to purple. In this study, a combination of metabolic and transcriptomic analyses was conducted at three stages of tepals in Michelia crassipes: green tepal, purple spot-containing tepal, and totally purple tepal. Several classes of flavonoid compounds were detected and cyanidin 3-rutinoside and delphinidin 3-glucoside were the major anthocyanins underlying the purple color formation, along with co-pigmentation of flavone compounds represented by luteolin derivatives and flavonol compounds represented by kaempferol and quercetin derivatives. Transcriptome analysis revealed up-regulation of genes encoding enzymes involved in the conversion of phenylpropanoid for flavonoid biosynthesis in Stage 1 vs. Stage 2, whereas up-regulation of most flavonoid biosynthesis genes was observed in Stage 1 vs. Stage 3. MYB, bHLH, and WD40 isoforms, as well as other classes of transcriptional factors, also exhibited differential expression. In addition, differentially expressed genes putatively related to the transport of flavonoids were also identified. The results of the current study provide insight into the regulatory mechanism underlying the color transition from green to purple in Michelia crassipes tepals and describe a complicated network involving PAL, transporter genes, and transcription factors, specifically responsible for the emergence of purple color in Stage 1 vs. Stage 2.


Assuntos
Flavonoides/biossíntese , Magnoliaceae/metabolismo , Pigmentação , Transcriptoma , Antocianinas , Cor , Flores/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metaboloma , Proteínas de Plantas/metabolismo
16.
Chem Commun (Camb) ; 56(57): 7941-7944, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32531007

RESUMO

We present herein a method for the controllable synthesis of 3-aryl-benzomorpholine and 2-aryl-benzomorpholine cycloadducts via cross-coupling/annulation between electron-rich 2-aminophenols and 4-vinylphenols. Molecular oxygen was successfully used in the reaction as the terminal oxidant and the complete inversion of chemoselectivity was achieved by the adjustment of the solvents and bases at room temperature.

17.
Front Microbiol ; 11: 327, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194532

RESUMO

With the emergence of multidrug-resistant and extensively drug-resistant bacterial pathogens, phage therapy and other alternative or additional therapeutic modalities are receiving resurgent attention. One of the major obstacles in developing effective phage therapies is the evolution of phage resistance in the bacterial host. When Pseudomonas aeruginosa was infected with a phage that uses O-antigen as receptor, phage resistances typically achieved through changing or loss of O-antigen structure. In this study, we showed that dsRNA phage phiYY uses core lipopolysaccharide as receptor and therefore efficiently kills the O-antigen deletion mutants. Furthermore, by phage training, we obtained PaoP5-m1, a derivative of dsDNA phage PaoP5, which is able to infect mutants with truncated O-antigen. We then generated a cocktail by mixing phiYY and PaoP5-m1 with additional three wide host range P. aeruginosa phages. The phage cocktail was effective against a diverse selection of clinical isolates of P. aeruginosa, and in the short-term constrained the appearance of the phage-resistant mutants that had beleaguered the effectiveness of single phage. Resistance to the 5-phage cocktail emerges after several days, and requires mutations in both wzy and migA Thus, this study provides an alternative strategy for designing phage cocktail and phage therapy.

19.
J Med Internet Res ; 21(9): e13587, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31507268

RESUMO

BACKGROUND: The rapid development of genetic and genomic technologies, such as next-generation sequencing and genome editing, has made disease treatment much more precise and effective. The technologies' value can only be realized by the aggregation and analysis of people's genomic and health data. However, the collection and sharing of genomic data has many obstacles, including low data quality, information islands, tampering distortions, missing records, leaking of private data, and gray data transactions. OBJECTIVE: This study aimed to prove that emerging blockchain technology provides a solution for the protection and management of sensitive personal genomic data because of its decentralization, traceability, encryption algorithms, and antitampering features. METHODS: This paper describes the case of a blockchain-based genomic big data platform, LifeCODE.ai, to illustrate the means by which blockchain enables the storage and management of genomic data from the perspectives of data ownership, data sharing, and data security. RESULTS: Blockchain opens up new avenues for dealing with data ownership, data sharing, and data security issues in genomic big data platforms and realizes the psychological empowerment of individuals in the platform. CONCLUSIONS: The blockchain platform provides new possibilities for the management and security of genetic data and can help realize the psychological empowerment of individuals in the process, and consequently, the effects of data self-governance, incentive-sharing, and security improvement can be achieved. However, there are still some problems in the blockchain that have not been solved, and which require continuous in-depth research and innovation in the future.


Assuntos
Blockchain , Segurança Computacional , Genômica/métodos , Disseminação de Informação , Algoritmos , Big Data , China , Humanos , Aplicativos Móveis , Propriedade , Privacidade , Software
20.
Ecotoxicol Environ Saf ; 182: 109390, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276884

RESUMO

Organochlorine pesticides have been banned for many years, but the residual trace amount of organochlorine in water may still pose ecotoxicological risk. Meanwhile, the potential risk of organochlorine pesticides released from sediments, especially into drinking water sources, is receiving increasing attention. The present study assessed the pollution and potential risk of drinking water sources along the midstream and downstream Yangtze River. Residues of organochlorine pesticides (OCPs) in water, suspended particle matter (SPM), and sediment were evaluated with isotope dilution HRGC/HRMS. The results indicated that OCPs in water, SPM, and sediment ranged in 0.52-92.97 ng/L, 0.10-4.10 ng/L, and 0.038-11.36 ng/g, respectively. The predominant OCPs in water, SPM, and sediment were ß-HCH, p,p'-DDE and PeCB. At site Y1, 8, 13, 18, ß-HCH has a higher proportion in sediment samples, while, α-HCH has a higher proportion in SPM samples. The industrial use of HCHs in the history was the main HCHs source for most water and sediment samples, which indicated an absence of fresh inputs of industrial HCHs. Meanwhile, the abundance of p,p'-DDE in water, sediment and SPM samples could be attributed to long-term aerobic degradation of DDTs. The values of ffsw of HCHs, DDTs and PeCB indicate the transfer from water to sediment. Risk assessment showed that HCHs and DDTs posed low ecotoxicological risk to the Yangtze River.


Assuntos
Diclorodifenil Dicloroetileno/análise , Água Potável/química , Monitoramento Ambiental/métodos , Hexaclorocicloexano/análise , Resíduos de Praguicidas/análise , Rios/química , China , Sedimentos Geológicos/química , Medição de Risco , Poluentes Químicos da Água/análise
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