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1.
J Environ Sci (China) ; 85: 82-93, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471034

RESUMO

Cannabis is increasingly used for both medicinal and recreational purposes with an estimate of over 180 million users annually. Canada has recently legalized cannabis use in October 2018, joining several states in the United States of America (e.g., Colorado, California, and Oregon) and a few other countries. A variety of cannabis products including dry flowers, edibles, and oil products are widely consumed. With high demand for cannabis products worldwide, the quality of cannabis and its related products has become a major concern for consumer safety. Various guidelines have been set by different countries to ensure the quality, safety, and efficacy of cannabis products. In general, these guidelines require control of contaminants including pesticides, toxic elements, mycotoxins, and pathogens, as well as residual solvents in regard to cannabis oil. Accordingly, appropriate analytical methods are required to determine these contaminants in cannabis products for quality control. In this review, we focus on the current analytical challenges and method development for detection of pesticides and toxic elements in cannabis to meet various guidelines.


Assuntos
Cannabis/química , Poluentes Ambientais/análise , Praguicidas/análise , Oligoelementos/análise , Estados Unidos
2.
Environ Monit Assess ; 191(8): 526, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363853

RESUMO

Biomonitoring has been used to disclose the public health impact of contaminated sites. This study aimed at setting up good practices to apply biomonitoring targeting animal matrixes to design risk-based surveillance and exposure assessment plans. A nine-step protocol targeting farmed animals was devised and tested in three case study areas including (1) a waste dump, (2) a waste incinerator, and (3) a secondary aluminum smelter. Between 2010 and 2012, in each study area, the following 9-step best practices were applied: hazard identification, GIS project creation, risk area delimitation, control area selection, receptors (livestock) identification, farms and matrixes selection, sampling study design, on-farm secondary sources exclusion, and statistical and geostatistical analysis. Dairy farms and free-range laying hens were the primary targets: eggs from both risk and control areas and milk from risk areas were sampled and submitted for detection of selected tracking contaminants compatible with the putative sources. Comparison data (risk vs. control) of heavy metal concentrations in eggs were available only for case study 2, whereas egg comparison data of persistent organic pollutants were available for all the risk-control pairs. After taking into account potential secondary sources, no concern from metals was arisen, whereas high concentrations of persistent organic pollutants were detected in all risk areas; however, only for the aluminum smelter case study, the contamination was broad and higher in the risk area compared with the control one. The protocol has proved to be easily applicable and flexible to varying contexts and able to provide helpful data to inform risk management decisions.


Assuntos
Ovos/análise , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Poluentes Ambientais/análise , Metais Pesados/análise , Leite/química , Animais , Bovinos , Galinhas , Feminino , Sistemas de Informação Geográfica , Itália , Medição de Risco , Instalações de Eliminação de Resíduos
3.
Environ Res ; 177: 108621, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421450

RESUMO

2,4,6-trinitrophenol (TNP) is environmentally deleterious substance that has been of pressing societal concern. Therefore, developing a convenient and reliable platforms for its fast and efficient detection is of paramount importance from security point of view. Herein, amphiphilic fluorescent carbon dots (CDs) were prepared by a simple solvothermal method. CDs exhibit high selectivity and sensitivity on TNP in the polar and apolar solvent and even natural water samples. Moreover, the simple and portable indicator paper can be prepared conveniently and used for sensing TNP visually with high sensitivity and fast response. Research findings obtained from this study would assist in the development of portable devices for the on-site and real-time detection of environmental hazards.


Assuntos
Carbono , Poluentes Ambientais/análise , Substâncias Explosivas/análise , Picratos/análise , Pontos Quânticos , Monitoramento Ambiental , Corantes Fluorescentes
4.
Environ Monit Assess ; 191(8): 477, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31264019

RESUMO

The present study evaluated the concentration of six trace elements in processed meat products and in meat cuts. We also assessed the risk associated with the consumption of these foods based on the estimated daily intake (EDI) of these elements. Fifty-eight processed meat and 148 meat cuts samples were analyzed using ICP-OES. As and Cd were not detected in any sample of processed meat. The highest mean level of lead was observed in frankfurters (0.056 µg g-1), which is half the maximum permissible level. For Cr, the highest mean concentrations were detected in chicken nuggets and beef hamburger (0.121 and 0.105 µg g-1, respectively), which are above the allowed limit. The comparison between the impact of a diet restricted to processed meats with a diet restricted to meats cuts showed that the individuals following the latter are exposed to higher amounts of the trace elements analyzed.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Carne , Oligoelementos/análise , Animais , Brasil , Bovinos , Galinhas , Manipulação de Alimentos , Análise de Perigos e Pontos Críticos de Controle , Humanos , Chumbo/análise , Medição de Risco
5.
Adv Exp Med Biol ; 1140: 731-741, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347081

RESUMO

Contaminant monitoring programs have been tasked with understanding the fate and transport of toxic chemicals in the environment. Mass spectrometry based methods have traditionally been developed to maximize sensitivity and accuracy of a select set of target compounds. As mass spectrometry methods have advanced, so has the breadth of questions proposed by environmental chemists. Incorporating these methods in chemical monitoring programs provides large data sets to explore the effects of complex mixtures on environmental systems.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Espectrometria de Massas
6.
Sci Total Environ ; 690: 965-972, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302560

RESUMO

The effects of grilling on health risks posed by polycyclic aromatic hydrocarbons (PAHs) in food remain poorly understood. The changes of concentrations, distributions, and risks of PAHs in vegetables and animal-based foods before and after grilling were investigated in this study. The sum of 16 (∑16) PAH concentrations in grilled vegetables and grilled animal-based foods were 60.4-1936 and 69.1-4668 ng/g, respectively. Grilling markedly increased the ∑16 PAH concentrations in most foods analyzed. Grilling clearly increased the low-molecular-weight PAH contributions to the ∑16 PAH concentrations in vegetables but increased the heavier PAH contributions to the ∑16 PAH concentrations in some animal-based foods. With the grilling, the total benzo[a]pyrene-equivalent concentrations of the 16 PAHs in Chinese chives and enoki mushrooms and most animal-based foods were improved significantly. Source assessments indicated that environmental sources contributed PAHs to the raw foods and high-temperature pyrolysis during grilling contributed large proportions of the PAHs in the grilled foods. The carcinogenic risks to humans from the exposure of PAHs in vegetables and animal-based foods were estimated. Grilling increased the total risks of PAHs in vegetables and animal-based foods by factors of 3.12 and 5.49, respectively. Total risks of PAHs in the 11 foods were 3.43 times higher when the foods were grilled than when raw. The results suggested that the negative effects of grilling on human health should be of great concern.


Assuntos
Exposição Dietética/estatística & dados numéricos , Poluentes Ambientais/análise , Carne/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Verduras/química , Culinária/métodos , Humanos
7.
Sci Total Environ ; 691: 393-400, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31323584

RESUMO

Lead is known as a potent toxicant to human health and there is currently an issue with lead contamination of food in China. This study analysed the regional characteristics of dietary lead intake of the Chinese population and used this to assess the health risks for each region due to the presence of lead in different foods. Data of dietary lead intake was used from the 4th and 5th Chinese Total Diet Studies (CTDS) covering 12 to 20 provinces. Over 200 kinds of food samples were divided and analysed. Results showed that lead consumption varies from region to region, with some, such as Heibei, being at higher risk and consuming larger amounts, and others, such as Shanxi, being at lower risk. It was found that the spatial correlation between lead intake from meats and vegetables was 0.545. The strong association between meats and vegetables shows that lead contamination has a large effect on fresh foods. The food groups with the highest contribution to lead intake were cereals and vegetables, while the food categories with the lowest contribution were dairy products, sugar, and alcohol. The main food group contributing to lead intake in different regions was found to be cereals in Hebei, vegetables in Heilongjiang and Ningxia, and meats in Sichuan and Hunan. The food products contributing the most to lead intake were found to be kelp and nori in many provinces and other notable foods included processed and preserved soybean, meat, and fungus products. These results allow policy makers to better target their efforts when working on the issue of lead contamination, focusing on areas of high contamination, and to advise consumers to adjust their diets to avoid high risk foods as this issue is being resolved.


Assuntos
Exposição Dietética/estatística & dados numéricos , Poluentes Ambientais/análise , Chumbo/análise , China , Dieta/estatística & dados numéricos
8.
Sci Total Environ ; 691: 631-643, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325863

RESUMO

Contaminants in the marine environment are widespread, but ship-based sampling routines are much narrower. We evaluated the utility of seabirds, highly-mobile marine predators, as broad samplers of contaminants throughout three tropical ocean regions. Our aim was to fill a knowledge gap in the distributions of, and processes that contribute to, tropical marine contaminants; and explore how species-specific foraging ecologies could inform or bias our understanding of contaminant distributions. Mercury and persistent organic pollutant (POPs) concentrations were measured in adults of five seabird species from four colonies in the central Pacific (Laysan and Tern Islands, Hawaii; Palmyra Atoll) and the eastern Caribbean (Barbuda). Blood-based total mercury (THg) and 89 POPs were measured in two seabird families: surface-foraging frigatebirds (Fregata spp.) and plunge-diving boobies (Sula spp.). Overall, largescale contaminant differences between colonies were more informative of contaminant distributions than inter-specific foraging ecology. Model selection results indicated that proximity to human populations was the best predictor of THg and POPs. Regional differences in contaminants were distinct: Barbudan Magnificent Frigatebirds had more compounds (n=52/89 POP detected) and higher concentrations (geometric mean THg=0.97µgg-1; mean ΣPOP53=26.6ngmL-1) than the remote colonies (34-42/89 POP detected; range of THg geometric means=0.33-0.93µgg-1; range of mean ΣPOP53:7.3-17.0ngmL-1) and had the most recently-synthesized POPs. Moderate differences in foraging ecologies were somewhat informative of inter-specific differences in contaminant types and concentrations between nearshore and offshore foragers. Across species, contaminant concentrations were higher in frigatebirds (THg=0.87µgg-1; ΣPOP53=17.5ngmL-1) compared to boobies (THg=0.48µgg-1; ΣPOP53=9.8). Ocean currents and contaminants' physiochemical properties provided additional insight into the scales of spatial and temporal contaminant exposure. Seabirds are excellent, broad samplers with which we can understand contaminant distributions in the marine environment. This is especially important for tropical remote regions that are under-sampled.


Assuntos
Aves/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Poluição Ambiental/estatística & dados numéricos , Animais , Poluentes Ambientais/análise , Mercúrio/análise
9.
Ecotoxicol Environ Saf ; 182: 109370, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31254859

RESUMO

Heavy metals, especially gaseous heavy metals, have high toxicity and do harm to human. Heavy metal volatilization characteristics of co-combusted municipal solid wastes (MSW) and sewage sludge (SS) from different mass fraction of MSW and SS, different temperature and different O2 concentration atmosphere was investigated. Performance of calcium-based sorbents was also studied. Volatilization efficiency of As, Cr, Cu, Ni, Pb and Zn in MSW was 100%, 45.89%-66.58%, 75.62%-92.45%, 42.33%-65.70%, 39.25%-68.76% and 53.57%-84.62%, and that in SS was 28.37%-40.75%, 33.78%-43.42%, 46.08%-56.69%, 35.04%-51.52%, 18.54%-44.99% and 14.72%-48.88%. Volatilization efficiency of heavy metals increased as mass fraction of SS in a blend decreased and as temperature increased. Volatilization efficiency of all heavy metals examined decreased as O2 concentration increased at high temperature and that of Cu, Pb and Zn increased as O2 concentration increased at low temperature. CaO, Ca(OH)2 and CaCO3 declined the volatilization of As, Cr, Cu, Ni, and Zn, while enhanced that of Pb. With calcium-based sorbents, volatilization efficiency of As, Cr, Cu, Ni, and Zn decreased from 70.06%, 39.91%, 75.52%, 44.08% and 40.10% to 54.24%, 33.73%, 39.98%, 20.56% and 32.06%, while that of Pb increased from 47.23% to 100%. Fitting formula was set to predict the heavy metals volatilization, and risk evaluation of gaseous heavy metals was exhibited.


Assuntos
Cálcio/química , Poluentes Ambientais/química , Incineração , Metais Pesados/química , Eliminação de Resíduos Líquidos , Adsorção , Poluentes Ambientais/análise , Gases , Humanos , Metais Pesados/análise , Esgotos , Resíduos Sólidos , Volatilização
10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(6): 645-652, 2019 Jun 06.
Artigo em Chinês | MEDLINE | ID: mdl-31177766

RESUMO

Dioxins, polybrominated diphenyl ethers, and benzo(a)pyrene are common organic pollutants in food. They have been of concern to academics and government administrations due to high residue and persistence, easy accumulation and strong harmful effects. The National Research Council of the United States of America published Toxicity Testing in the 21st Century: A Vision and Strategy in 2007, which proposed a new concept of toxicity testing that toxicity testing should take full consideration of population exposure data and base on in vitro tests, human cell lines, toxicity pathways and high-throughput screening. Meanwhile, systems biology, bioinformatics and rapid assay technologies will be used to better understand toxicity pathways-the cellular response pathways that can lead to adverse health effects when sufficient perturbing induced by chemicals exposure. The new toxicity testing strategy has changed the traditional testing pattern and has brought a wide impact on the international relevant fields. The European Union, the World Health Organization, and the United States Environmental Protection Agency, the Food and Drug Administration, and the National Center for Toxicological Research have organized relevant discussions and exploratory studies to address the new toxicity testing concept and how to evaluate and utilize the results of traditional toxicity test researches. Compared to the discussion, 'whether to do it', ten years ago, the question, 'how to do it', has become the concern of the current discussion. Therefore, how to respond to the concept of toxicity testing and how to effectively utilize and excavate traditional toxicity test data have been the focus of multi-disciplines and interdisciplinary academia such as toxicology, food hygiene and environmental science. Therefore, this article provides an overview of the exposure levels of dioxin, polybrominated diphenyl ethers and benzo[a]pyrene, which are typical persistent organic pollutants in food in China and the current research status of toxic pathways based on whole animal experiments. The exposure level, toxic effect and toxicity mechanism of three contaminants are analyzed and summarized in order to provide basis for future results based on the 21st century toxicity test compared with traditional tests and data mining analysis of these two kinds of data. Meanwhile, it also lays the foundation for the establishment of a toxicity testing framework based on exposure characteristics, toxic pathways, and biomarkers.


Assuntos
Poluentes Ambientais , Contaminação de Alimentos , Dibenzodioxinas Policloradas , Animais , China , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Humanos , Compostos Orgânicos/análise , Compostos Orgânicos/toxicidade , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/toxicidade , Pesquisa , Testes de Toxicidade
11.
Sci Total Environ ; 685: 308-314, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31176217

RESUMO

65 house dust samples from three European countries (Belgium, Italy and Spain) were evaluated for the presence of 20 polyflouroalkyl substances (PFASs) including perfluoroalkane sulfonic acids (PFSAs), perfluoroalkyl carboxylic acid (PFCAs) and perfluoroalkane sulfonamides (PFOSAs). The three countries presented similar PFAS levels ranging from 3.13 to 155 ng/g (12.9 ng/g; median), but in all cases PFCAs concentrations (6.92, 15.2 and 8.68 ng/g; median for Belgium, Italy and Spain) were higher than those obtained for PFSAs (2.30, 1.76 and 2.68 ng/g). Interestingly, in comparison to previously published data exhibited an increase in perfluorobutanesulfonate (PFBS) concentrations in Belgian house dust. On the other hand, levels of perfluorooctanesulfonate (PFOS) decreased in Spanish case. Data were examined for relationships between PFAS house dust levels, building and outdoor surrounding characteristics and occupant habits. Main findings revealed a positive association between PFOS concentrations and the building edification age, which could highlight a decrease in the use of this chemical in Europe. Similarly, perfluorohexanesulfonate (PFHxS) levels correlated with the percentage of the floor covered by textiles. Homes located in industrial sites showed higher PFCA levels compared to urban or agricultural locations, revealing the industrial processes as a potential source of these chemicals in Europe. Data obtained were used to perform human exposure assessment for dust intake via oral ingestion. Estimated daily intakes, calculated for toddlers and adults at median and worst case scenarios, were below oral Reference Dose (RfD) and tolerable daily intakes (TDI). However, in perfluorooctanoic acid (PFOA) case, dust ingestion significance to total dietary exposure reached values of 51% for toddlers in the worst case scenario.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Poeira/análise , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Ácidos Alcanossulfônicos , Caprilatos , Europa (Continente) , Fluorcarbonetos , Humanos
12.
Chemosphere ; 233: 771-785, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31200137

RESUMO

Pharmaceuticals which originally were designed to treat people with neurological and psychiatric conditions, e.g. Alzheimer's disease or attention deficit hyperactivity disorder (ADHD), are nowadays often misused by students as a 'brain doping' substances. These substances are known as nootropic drugs, smart drugs or cognitive enhancers, as they increase memory, attention and concentration of healthy individuals. Since they are easily available illicitly, their consumption is observed to be growing. Currently, these pharmaceuticals started gaining researchers' attention, especially since they have been recently detected in wastewater, surface water and even drinking water. This review summarises the current state of knowledge on nootropic drugs in terms of their population use trends and ethics, occurrence in the environment and detection techniques, toxicity and removal methods, in example of methylphenidate, modafinil and piracetam - three most popular nootropics. It points out that the main sources of knowledge on cognitive enhancers illicit use are often inconsistent questionnaires, which are not supported by wastewater analysis to become more veracious. Simultaneously, the studies concerning toxicity and removal methods of nootropic drugs are still limited and in many cases environmentally irrelevant. Although the prescription rules has been subjected to more strict control in developed countries, regulatory frameworks with regard to their ecosystem occurrence are still lacking and should be introduced. Moreover, the use of environmentally relevant concentrations in toxicity studies should be a standard, leading to proper ecotoxicity risk assessment. Based on this review, it is recommended to routinely monitor nootropics and their metabolites in waste- and surface waters.


Assuntos
Poluentes Ambientais/análise , Nootrópicos/análise , Transtorno do Deficit de Atenção com Hiperatividade , Encéfalo , Poluentes Ambientais/toxicidade , Humanos , Memória , Metilfenidato/análise , Metilfenidato/toxicidade , Modafinila/análise , Modafinila/toxicidade , Nootrópicos/toxicidade , Piracetam/análise , Piracetam/toxicidade , Águas Residuárias
13.
Ecotoxicol Environ Saf ; 181: 419-427, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31220782

RESUMO

Nonylphenol (NP) and its detrimental effects on the environment, humans, wildlife, fish and birds is an increasingly important global research focus. The number of investigations on the toxicity and metabolic fate of NP in plants is however limited. This paper reviews the prevalence and source of NP in plants and the effect it has on its morphological, physiological and ultrastructural status. Fruit and vegetables have been found to contain levels of NP that is twenty-fold exceeding the no observable effect level (NOEL) of freshwater algae. Apart from the potential risk this poses to the health of consumers, it can overburden the plant's natural defence system, leading to growth disorders. Plants exposed to NP show signs of overall growth reduction, changes in organelle structure and oxidative damage. These adverse effects may exacerbate the food security dilemma faced by many countries and impede their progress towards attaining the sustainable development goals.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Plantas/efeitos dos fármacos , Animais , Disruptores Endócrinos/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Humanos , Fenóis/análise , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas/anatomia & histologia , Plantas/metabolismo , Verduras/química , Verduras/crescimento & desenvolvimento
14.
Food Chem ; 295: 327-333, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174765

RESUMO

Dual-pulse laser-induced breakdown spectroscopy (DPLIBS) and chemometric methods were used to predict chromium content in rice leaves, along with the purpose for increasing the detection sensitivity and accuracy. The influence of important parameters in DPLIBS were investigated and optimized. Then, partial least square (PLS) was used to establish chromium content prediction models, and the value of regression coefficient based on PLS was applied to determine feature variables. In addition, multivariate and univariate analysis were used to verify the modeling performance of selected feature variables. The results indicated that support vector machine model based on feature variables achieved the best performance, with correlation coefficient of 0.9946, root mean square error of 4.85 mg/kg and residual predictive deviation of 9.70 in prediction set. The proposed method provides a high-accuracy and fast approach for chromium content prediction in rice leaves, which could potentially be used for toxic and nutrient elements detection in food.


Assuntos
Cromo/análise , Oryza/química , Folhas de Planta/química , Análise Espectral/métodos , Poluentes Ambientais/análise , Lasers , Análise dos Mínimos Quadrados , Luz , Sensibilidade e Especificidade , Análise Espectral/estatística & dados numéricos , Máquina de Vetores de Suporte
15.
J Environ Sci (China) ; 83: 85-95, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31221391

RESUMO

Metal pollution of stormwater runoff can cause potential toxic impacts on the receiving water environment and human health. Effective pollution mitigation requires accurate stormwater quality modeling. Even though a significant knowledge base exists on the factors influencing metal build-up on urban roads, very limited studies have investigated how metal-particulate interaction influences metal build-up. This study quantitatively assessed the influence of particulate characteristics, together with vehicular traffic and land use, on the build-up of Zn, Cu, Pb, Cr, Ni and Cd on urban roads. The study outcomes revealed that the variability in metal build-up is highly influenced by the variability associated with metal adsorption to particulates. The percentage contribution from particulate properties influencing metal adsorption in the case of <150 µm size road dust particles was found to be higher (Zn 44%, Cu 52%, Cr 16%, Ni 27% and Cd 45%) when compared to traffic and land use characteristics (Zn 21%, Cu 13%, Cr and Ni <10% and Cd 34%). Similar adsorption behavior was noted for metals associated with >150 µm size road dust particles. Among different particulate properties influencing metal adsorption, effective cation exchange capacity showed a strong positive relationship with the build-up of Cd compared to other metals, highlighting the potential role of Cd in stormwater quality as a readily available metal. The build-up of metals such as Cr and Ni are highly influenced by metal oxides of Al, Fe and Mn and clay forming minerals, indicating that Cr and Ni are relatively stable in nature.


Assuntos
Poeira/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Metais Pesados/análise , Adsorção , Tamanho da Partícula , Transportes
16.
Chemosphere ; 231: 510-517, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31151011

RESUMO

Porous carbon derived from amine-functionalized MIL-125 metal-organic framework (C-MIL-125-NH2) was prepared by carbonization at high temperature under inert atmosphere, and used for adsorption of bisphenol A (BPA) and 4-tert-butylphenol (4-tBP). The obtained carbon showed bimodal porosity and fast extraction of both pollutants in batch conditions following a pseudo-second-order model. The adsorption mechanism was studied by the measurement of zeta potential, and the results suggested that π-π stacking interactions between the carbon material and the phenol molecules probably are the main sorption mechanism. The prepared C-MIL-125-NH2 was incorporated into mechanically stable membranes for flow-through solid-phase extraction of studied phenols prior to HPLC analysis. The hybrid material showed excellent permeance to flow, easy regeneration and good performance for the simultaneous enrichment of mixtures of BPA and 4-tBP, facilitating their determination when present at low concentration levels.


Assuntos
Poluentes Ambientais/análise , Dietilamida do Ácido Lisérgico/análogos & derivados , Modelos Químicos , Adsorção , Compostos Benzidrílicos , Carbono , Cromatografia Líquida de Alta Pressão , Imidazóis , Dietilamida do Ácido Lisérgico/análise , Fenóis , Porosidade , Extração em Fase Sólida/métodos
17.
Environ Monit Assess ; 191(7): 409, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31165273

RESUMO

This study was conducted to investigate the concentrations, distributions, toxicities, and sources of polycyclic aromatic hydrocarbons (PAHs) in the soils from different areas in Ulsan, South Korea. Samples were collected from 41 sites, including a waste treatment facilities area (WA), traffic facilities area (TA), child playground area (CA), industrial area (IA), railroad facilities area (RA), ore and iron scraps fields area (OA), and residential area (ReA). Ulsan was chosen for research area because it used to be an environmental hot spot in South Korea, and 16 PAHs in the US EPA priority pollutant list were selected. The concentration of total PAHs (t-PAHs) ranged from 61.7 to 12,421 µg/kg, and the average concentration of t-PAHs was 706.9 µg/kg. The distribution of PAHs by ring number indicated that the portion followed the order of 4 rings > 5 rings > 3 rings > 6 rings > 2 rings. According to PAH origin indices, LMW/HMW (low molecular weight 2-3 ring PAHs over high molecular weight 4-6-ring PAHs), phenanthrene/anthracene ratio and fluoranthene/pyrene ratio, benzo(g,h,i)perylene/indeno (1,2,3-c,d)pyrene ratio, vehicular emissions, and the combustion of fossil fuel were the sources of PAHs. The strong correlation (R2 = 0.995) between t-PAHs and total carcinogenic PAHs (t-PAHcarc) indicated that the concentration of t-PAHcarc increased in proportion with that of t-PAHs. The toxic equivalent concentrations (TEQs) of PAHs in the soils ranged from 44.0 to 1929.9 µg TEQ/kg. It is imperative to set regulatory levels for PAHs for periodic monitoring and rapid remediation action of contaminated soils, because there are no national standards in South Korea for 15 PAHs with the exception of benzo(a)pyrene.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Poluição Ambiental/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Solo/química , Benzo(a)pireno/análise , Benzo(a)pireno/toxicidade , Fluorenos/análise , Fluorenos/toxicidade , Humanos , Indústrias , República da Coreia , Emissões de Veículos/análise , Instalações de Eliminação de Resíduos
18.
Talanta ; 202: 384-391, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171199

RESUMO

A novel microfluidic paper-based analytical device (µPAD) was developed with benzoquinone (BQ)-mediated E. coli respiration method to measure the biotoxicities of pollutants. Functional units including sample injection, fluid-cell separation, all-carbon electrode-enabled electrochemical detection, were integrated on a piece of chromatography paper. The three-electrode, working electrode, counter electrode and reference electrode, were simultaneously screen-printed on the µPAD with conductive carbon ink. The satisfying electrochemical performance of the paper-based carbon three-electrode was confirmed by cyclic voltammetry detecting K3 [Fe(CN)6]. The process of cell toxication was considered that toxicants inhibited cell respiration and diminished the electrons on E. coli respiratory chain. It was quantitatively reflected by measuring oxidation current of hydroquinone (HQ) as a reduced state of the redox mediator BQ after the incubation of cells with pollutants. The current detection time, BQ concentration and E. coli incubation time were carefully optimized to establish the systematic optimized operations of BQ-mediated E. coli respiration method. Using the fabricated µPAD the half inhibitory concentration (IC50) were Cu2+ solution 13.5 µg mL-1, Cu2+-soil 21.4 mg kg-1, penicillin sodium-soil 85.1 mg kg-1, and IC30 of Pb2+ solution was 60.0 µg mL-1. Detection of pesticide residues in vegetable juices were accomplished in a similar way. The proposed method is fascinating on three points; 1) The generality in the biotoxicity detection depends on toxicants inducing cellular respiratory inhibition; 2) The portability and affordability make it convenient for practical applications, because of replacing incubators and centrifuges; 3) There is potential applicability in less-developed areas due to its simple operation and low-cost.


Assuntos
Técnicas Eletroquímicas , Poluentes Ambientais/farmacologia , Escherichia coli/efeitos dos fármacos , Técnicas Analíticas Microfluídicas , Papel , Benzoquinonas/química , Eletrodos , Poluentes Ambientais/análise , Escherichia coli/citologia , Escherichia coli/metabolismo
19.
Ann Agric Environ Med ; 26(2): 273-279, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31232059

RESUMO

INTRODUCTION: Mercury release in the environment is mainly the result of human activity, particularly from coal-fired power stations, residential heating systems, waste incinerators, and as a result of mining for mercury, gold and other metals, which have led to widespread global mercury pollution. Excessive exposure to mercury is associated with a wide range of adverse health effects, including damage to the central nervous system, digestive and immune systems, and to lungs, kidneys, skin and eyes. OBJECTIVE: The main aim of the study is to summarize the selected mercury sources in the environment of the Slovak Republic, regarding waste incinerators, landfill waste, crematoria, chemical plants, rivers and soils. BRIEF DESCRIPTION OF STATE OF KNOWLEDGE: Although the neurologic symptoms of Minamata disease were identified sufficiently for specialists to classify mercury as the causative agent, the acceptance of mercury´s environmental impacts will require several decades of research. Several new issues have arisen - the need for energy conservation leads to the use of fluorescent lighting, which contain mercury; emissions driven by increases in coal combustion, incineration and economic development have sent more mercury into the air, soil and water. CONCLUSIONS: Mercury is toxic to human health, posing a particular threat to the development of the child in utero and early in life. The systematic analytical controls of contaminants in water, soil and air are important. The installation of modern cleaning technologies to comply with the maximum emission level can substantially minimized the environmental impact of incinerators. Since human cremation is also an increasing practice, further research on mercury emissions is necessary.


Assuntos
Poluentes Ambientais/análise , Mercúrio/análise , Poluição Ambiental/análise , Eslováquia
20.
Chemosphere ; 232: 471-480, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31163323

RESUMO

Pesticide residues in beebread, live and dead honey bees, together with honey bee death rate were monitored from June 2016 to June 2018 in three apiaries, located near agricultural settings and in wildlands. Dead honey bees were only collected and analyzed when significant mortality episodes occurred and pesticide content in beeswax of each experimental apiary was evaluated at the beginning of the study. Samples were extracted by a modified QuEChERS procedure and screened for pesticides residues by liquid chromatography mass spectrometry (LC-MS/MS). Pesticide hazard in the samples was evaluated through the hazard quotient approach (HQ). Beebread was widely contaminated with coumaphos and amitraz degradate 2, 4-dimethylphenylformamide (DMF), miticides detected in 94 and 97% of samples respectively. However, insecticides sprayed during citrus bloom like chlorpyrifos (up to 167 ng g -1) and dimethoate (up to 34 ng g -1) were the main responsible of the relevant pesticide hazard in this matrix. Pesticide levels in live bees were mostly residual, and pesticide hazard was low. Beeswax of the apiaries, contaminated by miticides, revealed a low pesticide hazard to honey bee colonies. Acute mortality episodes occurred only in the two apiaries located near agricultural settings. Dead bees collected during these episodes revealed high levels (up to 2700 ng g -1) of chlorpyrifos, dimethoate, omethoate and imidacloprid. HQ calculated in dead bees exceeded up to 37 times the threshold value considered as elevated hazard to honey bee health.


Assuntos
Abelhas/efeitos dos fármacos , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Acaricidas/análise , Acaricidas/envenenamento , Agricultura , Animais , Abelhas/química , Abelhas/crescimento & desenvolvimento , Monitoramento Ambiental/instrumentação , Poluentes Ambientais/toxicidade , Inseticidas/toxicidade , Resíduos de Praguicidas/toxicidade , Própole/química , Espanha , Análise de Sobrevida , Ceras/química
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