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1.
Environ Monit Assess ; 194(9): 603, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35864363

RESUMO

This literature review focuses on land quality evaluation (LQE) and its effects on sustainable development through quantitative analysis and value-added information. In contrast to the traditional perspective, a structured review based on bibliometric indicators and social network analysis allows identifying hidden evidence for answering the following research questions: (i) What: What is the application of LQE? (ii) Which: Which sustainable development goals does the application contribute to? (iii) Why and how: What are the main applications and methods of each topic? (iv) Where: Where is the hotspot of the problem? What is the future research orientation of the topic? (v) How and when: How has the topic grown since 2000? Data investigation explores 4029 articles in 2000-2019 from four publishers. With the support of VOSviewer software, six clusters corresponding to six main applications of LQE are classified. Overlapping keywords in several clusters are resolved by the binary term frequency counter for the cluster preference determination. After conducting the data verification and editing process, a structured review is performed again with systematic research questions. This research offers a synthesis of traditional and novel quantitative analysis for literature review, which is comprehensive, accurate, and reliable.


Assuntos
Análise de Rede Social , Desenvolvimento Sustentável , Bibliometria , Monitoramento Ambiental , Software
2.
Environ Geochem Health ; 42(11): 3597-3608, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32415403

RESUMO

Phytoremediation and advanced oxidation processes are among the most promising techniques for removing organic pollutants from soils. A field trial was performed for six months to evaluate the effect of nano-Fe3O4 on the degradation of organochlorine pesticide residues including Lindane, p,p'-dichlorodiphenyltrichloroethane (DDT), p,p'-dichlorodiphenyldichloroethylene (DDE), and p,p'-dichlorodiphenyldichloroethane (DDD) in pesticide-contaminated soils in the presence of vetiver in Bac Giang province, Vietnam. Vetiver was planted in three zones with different nano-Fe3O4 concentrations. Soil samples from each zone were periodically collected to determine the remaining concentrations of selected organochlorine pesticides via gas chromatography-electron capture detector. Results indicated that the total DDT concentrations in the examined soil were 1.9-13 times higher than the permissible threshold level (10 µg g-1) established by the national technical regulation on pesticide residues in soil. The (p,p'-DDE + p,p'-DDD)/p,p'-DDT ratios ranged from 13.5 to 114, indicating the absence of recent inputs of technical DDTs at the study area. DDT dechlorination mainly occurred under aerobic pathways to form DDE. Furthermore, DDE degradation in soil was adequately described by the pseudo-first-order kinetics model (R2 > 0.892). In the presence of vetiver, the rate constants of DDE degradation were 0.264, 0.350, and 0.434 month-1 with 0, 25, and 100 mg kg-1 of added nano-Fe3O4, respectively, indicating that the degradation of DDE correlated positively with Fe3O4 concentration in the soil. Additionally, the presence of vetiver and nano-Fe3O4 in the soil increased DDT removal rates, which might be linked to the involvement of Fenton/Fenton-like reactions.


Assuntos
Vetiveria , Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos Clorados/química , Resíduos de Praguicidas/química , Poluentes do Solo/química , Cromatografia Gasosa , DDT/análise , DDT/química , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/química , Hexaclorocicloexano/análise , Hexaclorocicloexano/química , Hidrocarbonetos Clorados/análise , Peróxido de Hidrogênio/química , Ferro/química , Nanopartículas de Magnetita/química , Resíduos de Praguicidas/análise , Solo/química , Poluentes do Solo/análise , Vietnã
3.
J Environ Sci Health B ; 55(5): 417-428, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31880201

RESUMO

A GC-MS/MS method with low solvent consumption and easy operation was developed to simultaneously determine ten new-generation pesticides, namely fenobucarb, acetochlor, pretilachlor, fipronil, trifloxystrobin, fluazifop-p-butyl, isoprothiolane, tebuconazole, cypermethrin and difenoconazole in leafy vegetables. Influences from ultrasonic sample extraction and the clean-up steps to reduce matrix effects were investigated. Under suitable conditions, good linearity (deviation of back calculated concentration from true concentration lower than 20%) was achieved for all studied pesticides; the method detection limits (MDLs) ranged from 1.4 to 3.6 ng g-1 wet weight. For mustard green and green onion the method yielded good recoveries at two spiking levels (201 and 100 ng g-1) ranging from 80% to 111% (n = 5). The repeatability, expressed as relative standard deviation (RSD), was lower than 11% (n = 5). The method was successfully used to quantify pesticide residues in 207 vegetable samples (green onions, mustard greens, and lettuce) collected in Thua Thien Hue and Quang Binh Provinces, Central Vietnam. The insecticide cypermethrin was found at critical levels in 98% of the vegetable samples. Green onions had high pesticide residues with a significant number of samples containing pesticides at concentrations exceeding the maximum residue levels (MRLs).


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Verduras/química , Limite de Detecção , Resíduos de Praguicidas/análise , Solventes/química , Espectrometria de Massas em Tandem/métodos , Vietnã
4.
BMC Infect Dis ; 14: 362, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24992826

RESUMO

BACKGROUND: Sporadic emergence of the highly pathogenic avian influenza (HPAI) H5N1 virus infection in humans is a serious concern because of the potential for a pandemic. Conventional or quantitative RT-PCR is the standard laboratory test to detect viral influenza infections. However, this technology requires well-equipped laboratories and highly trained personnel. A rapid, sensitive, and specific alternative screening method is needed. METHODS: By a luminescence-linked enzyme immunoassay, we have developed a H5N1 HPAI virus detection kit using anti-H5 hemagglutinin monoclonal antibodies in combination with the detection of a universal NP antigen of the type A influenza virus. The process takes 15 minutes by use of the fully automated luminescence analyzer, POCube. RESUTLS: We tested this H5/A kit using 19 clinical specimens from 13 patients stored in Vietnam who were infected with clade 1.1 or clade 2.3.4 H5N1 HPAI virus. Approximately 80% of clinical specimens were H5-positive using the POCube system, whereas only 10% of the H5-positive samples were detected as influenza A-positive by an immunochromatography-based rapid diagnostic kit. CONCLUSIONS: This novel H5/A kit using POCube is served as a rapid and sensitive screening test for H5N1 HPAI virus infection in humans.


Assuntos
Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Humana/virologia , Humanos , Técnicas Imunoenzimáticas , Faringe/virologia , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Vietnã
5.
Transplant Cell Ther ; 30(1): 71.e1-71.e13, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37890590

RESUMO

Previous studies in mice demonstrated that CD8 T cells exhibit marked veto activity enhancing engraftment in several models for T cell-depleted bone marrow (TDBM) allografting. To reduce the risk of graft-versus-host disease (GVHD) associated with allogeneic CD8 veto T cells, these studies made use of naive CD8 T cells stimulated against third-party stimulators under cytokine deprivation and subsequent expansion in the presence of IL-15. More recently, it was shown that mouse CD8 veto T cells can be generated by stimulating CD8 memory T cells from ovalbumin immunized mice under cytokine deprivation, using ovalbumin as a third-party antigen. These cells also exhibited substantial enhancement of BM allografting without GVHD. In this study, we tested the hypothesis that stimulation and expansion of human CD8 memory T cells under IL-15 and IL-7 deprivation during the early phase of activation against recall viral antigens can lead to substantial loss of alloreactive T clones while retaining marked veto activity. Memory CD8 T cells were enriched by removal of CD45RA+, CD4+, and CD56+ cells from peripheral blood of cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-positive donors. In parallel, CD14+ monocytes were isolated; differentiated into mature dendritic cells (mDCs); pulsed with a library of CMV, EBV, adenovirus, and BK virus peptides; and irradiated. The CD8 T cell-enriched fraction was then cultured with the pulsed mDCs in the presence of IL-21 for 3 days, after which IL-15 and IL-7 were added. After 12 days of culture, the cells were tested by limiting dilution analysis for the frequency of alloreactive T cell clones and their veto activity. In preclinical runs using GMP reagents, we established that within 12 days of culture, a large number of highly homogenous CD8 T cells, predominantly expressing a central memory phenotype, could be harvested. These cells exhibited marked veto activity in vitro and >3-log depletion of alloreactivity. Based on these preclinical data, a phase 1-2 clinical trial was initiated to test the safety and efficacy of these antiviral CD8 central memory veto cells in the context of nonmyeloablative (NMA) T cell-depleted haploidentical hematopoietic stem cell transplantation (HSCT). In 2 validation runs and 11 clinical runs using GMP reagents, >1 × 1010 cells were generated from a single leukapheresis in 12 out of 13 experiments. At the end of 12 days of culture, there were 97 ± 2.5% CD3+CD8+ T cells, of which 84 ± 9.0% (range, 71.5% to 95.1%) exhibited the CD45RO+CD62L+ CM phenotype. Antiviral activity tested by intracellular expression of INF-γ and TNF-α and showed an average of 38.8 ± 19.6% positive cells on 6 hours of stimulation against the viral peptide mixture. Our results demonstrate a novel approach for depleting alloreactive T cell clones from preparations of antiviral CD8 veto cells. Based on these results, a phase 1-2 clinical trial is currently in progress to test the safety and efficacy of these veto cells in the context of NMA haploidentical T cell-depleted HSCT. Studies testing the hypothesis that these non-alloreactive CD8 T cells could potentially offer a platform for off-the-shelf veto chimeric antigen receptor T cell therapy in allogenic recipients, are warranted.


Assuntos
Infecções por Citomegalovirus , Infecções por Vírus Epstein-Barr , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Camundongos , Animais , Linfócitos T CD8-Positivos/metabolismo , Interleucina-15 , Células T de Memória , Interleucina-7 , Ovalbumina , Herpesvirus Humano 4/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Antígenos Comuns de Leucócito/metabolismo , Antivirais
6.
Int J Radiat Oncol Biol Phys ; 119(1): 234-250, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37981041

RESUMO

PURPOSE: Radiation therapy (RT) has been shown to effectively induce the expression of intercellular adhesion molecule-1 (ICAM-1), which is recognized by lymphocyte function-associated antigen 1 (LFA-1) expressed on natural killer (NK) cells. However, the potential synergistic antitumor immune response of tumor irradiation and administered NK cells has not been explored in intractable human liver cancers. Furthermore, NK cell targeting against both parental and cancer stemness has never been investigated. METHODS AND MATERIALS: Highly activated ex vivo NK cells were administered into the human liver tumor-bearing mice. Tumor direct RT was optimized according to tumor bearing site. HepG2 and Hep3B ICAM-1 knockout cells were generated using CRISPR/CAS9. Stemness tumor spheres were generated. NK cell cytolysis against parental and tumor sphere was evaluated using flow cytometry and real-time cytotoxicity assay. RESULTS: A combination of adoptive NK cell therapy with RT significantly improved therapeutic efficacy over monotherapies against subcutaneous, orthotopic, and metastatic human liver tumor models. Direct tumor irradiation potentiated NK cell recognition and conjugation against liver cancer through the LFA-1/ICAM-1 axis. Suppression of immune synapse formation on NK cells using high-affinity LFA-1 inhibitors or ICAM-1 knockout liver cancer induced "outside-in" signal blocking in NK cells, resulting in failure to eliminate liver tumor despite the combination therapy. NK cells effectively recognized and targeted triple-high epithelial cell adhesion molecule+CD133+CD24+ liver cancer expressing upregulated ICAM-1 in the irradiated tumor microenvironment, which led to prevention of the initiation of metastasis, improving survival in a metastatic model. In addition, the LFA-1/ICAM-1 axis interruption between NK cells and stemness liver tumor spheres significantly diminished NK cell cytolysis. Consistent with our preclinical data, the LFA-1/ICAM-1 axis correlated with survival outcomes in patients with metastatic cancer from the The Cancer Genome Atlas databases. CONCLUSIONS: NK cells in combination with tumor irradiation can provide synergistic therapeutic effects for NK cell recognition and elimination against both parental and stemlike liver cancer through LFA-1/ICAM-1.


Assuntos
Molécula 1 de Adesão Intercelular , Neoplasias Hepáticas , Humanos , Camundongos , Animais , Antígeno-1 Associado à Função Linfocitária/metabolismo , Antígeno-1 Associado à Função Linfocitária/farmacologia , Citotoxicidade Imunológica , Células Matadoras Naturais , Neoplasias Hepáticas/metabolismo , Pais , Microambiente Tumoral
7.
PLoS One ; 17(9): e0274673, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36107924

RESUMO

This work proposed a novel procedure of Water Quality Index (WQI) development that could be used for practical applications on a local or regional scale, based on available monitoring data. Principal component analysis (PCA) was applied to the monthly data of 11 water quality parameters (pH, conductivity (EC), total suspended solid (TSS), dissolved oxygen (DO), five -day biological oxygen demand (BOD), chemical oxygen demand (COD), ammonia (N-NH4), nitrate (N-NO3), phosphate (P-PO4), total coliform, and total dissolved iron monitored at 11 sites at Huong river in the years 2014-2016. From the PCA, the three extracted principal components explained 67% of the total variance of original variables. From the set of communality values, the weight (wi) for each parameter was determined. Linear sub-index functions were established based on the permissible limits from the National Technical Regulations on Surface Water Quality set up by the Vietnam Environment Agency (VEA) to derive the sub-index (qi) for each parameter. The multiplicative formula that is the product of the sub-indices (qi) raised to the respective weights (wi), was used for calculation of the final WQI values. The proposed index (WQI) was then applied to the river with quarterly data of the 11 parameters monitored at ten sites in the years 2017-2020. The WQI representatively reflected the actual status of the river overall water quality, of which 97.8% of the WQI values belonged to grades of EXCELLENT and GOOD, and 2.2% of grade MODERATE. Comparison between the river water quality evaluations resulting from the developed WQI with the WQI adopted by National Sanitation Foundation (NSF-WQI) and the index issued by Vietnam Environment Agency (VN-WQI) indicated that the proposed WQI was more suitable for river quality assessment.


Assuntos
Rios , Qualidade da Água , Amônia/análise , Monitoramento Ambiental/métodos , Ferro/análise , Nitratos/análise , Oxigênio/análise , Fosfatos/análise , Vietnã
8.
Environ Sci Pollut Res Int ; 29(10): 14046-14057, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34601679

RESUMO

The occurrence of nine phthalic acid esters (PAEs) were determined in indoor dust samples collected from vehicle repair shops, waste processing workshops, and homes in Vietnam. Concentrations of total PAEs ranged from 585 to 153,000 (median 33,400 ng/g), which fall in the lower end of global range. The PAE levels in workplace dust (median 49,100; range 9210-153,000 ng/g) were significantly higher than those in house dust (median 23,700; range 585-83,700 ng/g), indicating waste processing activities as potential PAE sources. The most predominant compound was di-(2-ethyl)hexyl phthalate (DEHP), accounting for 62 ± 18% of total PAEs. Other major compounds were benzyl butyl phthalate (BzBP) (10 ± 12%), di-n-butyl phthalate (DnBP) (9.7 ± 7.7%), di-n-octyl phthalate (DnOP) (7.9 ± 8.1%), and diisobutyl phthalate (DiBP) (6.9 ± 5.0%). Proportions of BzBP and DnBP in some workplace dust samples were markedly greater than in common house dust, suggesting specific emission sources. Daily intake doses of selected PAEs (e.g., DnBP, DiBP, BzBP, and DEHP) through dust ingestion were much lower than reference doses, implying acceptable levels of risk.


Assuntos
Poeira , Ácidos Ftálicos , China , Poeira/análise , Ésteres/análise , Ácidos Ftálicos/análise , Vietnã , Local de Trabalho
9.
PLoS One ; 17(6): e0269789, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35696374

RESUMO

Pesticide residue in food, especially in vegetables, is one of the important parameters to assess food safety. This study evaluates the pesticide use in vegetables from two provinces in Central Vietnamand and present data on pesticides detected in vegetables sampled from the sites. The potential health risk associated with the contamination of four commonly used pesticides in different vegetables is also discussed. Both household surveys and monitoring campaigns were conducted. The survey showed that improper pesticide application, storage, and waste disposal prevailed at the study sites. Only 20% of the respondent were aware of pesticide toxicity. As a result, pesticides were detected in 81% out of 290 vegetable samples collected at harvesting time. Up to 23% of samples had pesticide residues above the Maximum Residue Limit values. The highest total pesticide concentration quantified in vegetables in Thua Thien Hue was 11.9 mg/kg (green onions), and in Quang Binh was 38.6 mg/kg (mustard greens). Median residue levels of individual pesticides in vegetables ranged from 0.007 to 0.037 mg/kg. Among the ten target pesticides, cypermethrin, difenoconazole, and fenobucarb were detected at the highest frequencies (72%, 41%, and 37%, respectively). Pesticide residues varied between seasons at both study provinces. Pesticide contamination in the wet season was significantly higher than in the dry season. This study also discovered a potential health risk associated with fipronil residues in vegetables in Thua Thien Hue province. The paper provides recommendations for mitigation measures (both technological and social) in reducing potential health risks linked to pesticide use in vegetables in the region.


Assuntos
Resíduos de Praguicidas , Praguicidas , Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Praguicidas/análise , Verduras/química , Vietnã
10.
ACS Omega ; 7(11): 9397-9405, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350314

RESUMO

A novel polysaccharide structure (PS-T80) was collected from Ophiocordyceps sobolifera biomass and characterized via a combination of chemical and spectral analyses. Employing high-performance gel permeation chromatography (HPGPC), the average molecular weight is proven to be 7.4 × 104 Da. Furthermore, a sugar composition analysis of the obtained polysaccharide suggests two main sugars, ß-d-glucose and α-d-mannose, at a molar ratio of 2:1, respectively, in the backbone. The structure analysis unveils that PS-T80 is a mannoglucan, possessing the repeating unit of [→3)-ß-d-Glcp-(1 → 3)-α-d-Manp-(1 → 3)-ß-d-Glcp-(1→] n . Such a configuration could be considered a novel polysaccharide. Impressively, in vitro antioxidant tests revealed that PS-T80 has a promising antioxidant activity. These results demonstrate that the obtained PS is a potential bioactive material for biomedical applications.

11.
ACS Omega ; 7(51): 47923-47932, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36591194

RESUMO

The presented study attempts to unveil and evaluate the antioxidant activity of a novel heteropolysaccharide separated from the roots of Myxopyrum smilacifolium (denoted as PS-MSR). The molecular weight of PS-MSR is found to be 1.88 × 104 Da and contains two principal sugars, which are d-glucose and d-fructose, in the backbone. Decoding the structure of the obtained PS-MSR sample has disclosed a novel polysaccharide for the first time. Indeed, the PS-MSR is composed of (1 → 3)-linked glucosyl units and (2 → 3)-linked fructosyl units. In addition, the 1D and 2D NMR spectra of the PS-MSR sample display the repeating unit of the isolated polysaccharide, [→3)-α-d-Glcp-(1 → 3)-ß-d-Frucf-(2 → 3)-ß-d-Frucf-2 → 3)-)-ß-d-Frucf-ß-(2→] n . Interestingly, the PS-MSR sample exhibits outstanding antioxidant activity, signifying the potential utilization of the explored polysaccharide for antioxidant-based material.

12.
PLoS One ; 16(7): e0253908, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197520

RESUMO

The primary aim of this study is to propose a potential landscape value assessment from different dimensions rather than the traditional approach of a composite indicator. The method used in this study is the combination of data collection from stakeholder survey, score measurement for landscape value dimensions using Structural Equation Modeling (SEM), and spatial representation with the support of Geographic Information System (GIS). From a large-scale (n = 400) investigation in the Moc Chau district, the statistical data extracted from the survey provides input data for the score determination process. SEM analysis shows that each landscape site has 11 determinants influencing the landscape value assessment. Using the RMSE comparison (for validation) with different interpolation methods, the ordinary kriging method is chosen to model the aggregation landscape value map of Moc Chau District. About 24.97% total area of the study area has great potential for tourism development, being mainly distributed in the center of a high mountainous area. This approach can be used as a model to advocate local and regional assessment and enhance value-based management in other territories in Vietnam and beyond.


Assuntos
Ecologia , Turismo , Sistemas de Informação Geográfica , Geografia , Análise de Classes Latentes , Análise Espacial , Vietnã
13.
Wellcome Open Res ; 6: 278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36176331

RESUMO

This article summarises a recent virtual meeting organised by the Oxford University Clinical Research Unit in Vietnam on the topic of climate change and health, bringing local partners, faculty and external collaborators together from across the Wellcome and Oxford networks. Attendees included invited local and global climate scientists, clinicians, modelers, epidemiologists and community engagement practitioners, with a view to setting priorities, identifying synergies and fostering collaborations to help define the regional climate and health research agenda. In this summary paper, we outline the major themes and topics that were identified and what will be needed to take forward this research for the next decade. We aim to take a broad, collaborative approach to including climate science in our current portfolio where it touches on infectious diseases now, and more broadly in our future research directions. We will focus on strengthening our research portfolio on climate-sensitive diseases, and supplement this with high quality data obtained from internal studies and external collaborations, obtained by multiple methods, ranging from traditional epidemiology to innovative technology and artificial intelligence and community-led research. Through timely agenda setting and involvement of local stakeholders, we aim to help support and shape research into global heating and health in the region.

14.
J Pestic Sci ; 45(4): 245-252, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33304195

RESUMO

This study was designed to understand the dissipation of fipronil, cypermethrin, and tebuconazole in green onions and mustard greens grown in Central Vietnam. A field trial on ca. 400 m2 was implemented for two months with three different cropping regimes (natural plot-fully exposed to natural conditions; bed plot-fenced in by plastic sheets with an open roof; and protected plot-fully covered by plastic sheets) for each vegetable. A first-order kinetic model was successfully employed to interpret the dissipation data of each studied pesticide. A comparing the dissipation rate constants obtained under the same crop and growing regime between chemicals suggested that, among the chemicals examined, fipronil dissipated most readily. The pesticides were also proven to be more persistent in crops grown in protected plots than those grown in natural plots. The half-lives for fipronil, cypermethrin, and tebuconazole fluctuated, occurring at 0.4-2.2 days, 2.0-6.0 days, and 0.9-3.3 days, respectively.

16.
Chemosphere ; 184: 1117-1124, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28672692

RESUMO

Earlier studies have reported the occurrence of cyclic and linear siloxanes in personal care and household products. Nevertheless, there is a lack of information on the occurrence of siloxanes in indoor air. In this study, four cyclic and six linear siloxanes were measured in 97 indoor air samples collected from various micro-environments in four cities in northern, Vietnam, during September 2016 to January 2017. The total concentrations of siloxanes (TSi) in particulate and gas phases ranged from 141 to 7220 µg g-1 (mean: 1880) and 23.8-1580 ng m-3 (mean: 321), respectively. The total concentrations of cyclic siloxanes (TCSi), linear siloxanes (TLSi), and TSi in indoor air were 1.91-1500 ng m-3, 21.8-817 ng m-3, and 41.8-1950 ng m-3, respectively. The highest mean concentration of siloxanes was found in indoor air from hair salons in Hanoi. The concentrations of siloxanes in air collected from homes in Hanoi were higher than those from other smaller cities such as Bacninh, Thaibinh, and Tuyenquang. The human exposures to siloxanes through inhalation were estimated for various age groups based on the measured concentrations. The mean inhalation exposure doses to total siloxanes for infants, toddlers, children, teenagers, and adults were 352, 219, 188, 132, and 95.9 ng kg-bw-1 d-1, respectively.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/estatística & dados numéricos , Siloxanas/análise , Adolescente , Adulto , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Criança , Pré-Escolar , Cidades , Meio Ambiente , Exposição Ambiental/análise , Cabelo/química , Produtos Domésticos , Humanos , Lactente , Exposição por Inalação/análise , Exposição por Inalação/estatística & dados numéricos , Masculino , Vietnã
17.
PLoS One ; 10(7): e0131855, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26135396

RESUMO

The Mekong Delta in Vietnam has seen a rapid development and intensification of aquaculture in the last decades, with a corresponding widespread use of antibiotics. This study provides information on current antibiotic use in freshwater aquaculture, as well as on resulting antibiotic concentrations in the aquatic environment of the Mekong Delta. Two major production steps, fish hatcheries and mature fish cultivation, were surveyed (50 fish farm interviews) for antibiotic use. Different water sources, including surface water, groundwater and piped water (164 water samples) were systematically screened for antibiotic residues. To better understand antibiotic fate under tropical conditions, the dissipation behavior of selected antibiotics in the aquatic environment was investigated for the first time in mesocosm experiments. None of the investigated antibiotics were detected in groundwater and piped water samples. Surface water, which is still often used for drinking and domestic purposes by local populations, contained median concentrations of 21 ng L-1 sulfamethoxazole (SMX), 4 ng L-1 sulfadiazine (SDZ), 17 ng L-1 trimethoprim (TRIM), and 12 ng L-1 enrofloxacin (ENRO). These concentrations were lower than the predicted no effect concentrations (PNECs) and minimum inhibitory concentrations (MICs), suggesting limited antibiotic-related risk to aquatic ecosystems in the monitored systems. The dissipation half-lives of the studied antibiotics ranged from <1 to 44 days, depending on the availability of sunlight and sediment. Among the studied antibiotics TRIM was the most persistent in water systems. TRIM was not susceptible to photodegradation, while the dissipation of ENRO and SDZ was influenced by photolysis. The recorded dissipation models gave good predictions of the occurrence and concentrations of TRIM, ENRO and SDZ in surface water. In summary, the currently measured concentrations of the investigated antibiotics are unlikely to cause immediate risks to the aquatic environment, yet the persistence of these antibiotics is of concern and might lead to chronic exposure of aquatic organisms as well as humans.


Assuntos
Antibacterianos/análise , Fluoroquinolonas/análise , Rios , Sulfadiazina/análise , Sulfametoxazol/análise , Trimetoprima/análise , Poluentes Químicos da Água/análise , Animais , Enrofloxacina , Monitoramento Ambiental , Pesqueiros , Água Doce , Geografia , Água Subterrânea , Medição de Risco , Vietnã
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