Ecotoxicological Evaluation of Methiocarb Electrochemical Oxidation

The ecotoxicity of methiocarb aqueous solutions treated by electrochemical oxidation was evaluated utilizing the model organism Daphnia magna. The electrodegradation experiments were performed using a boron-doped diamond anode and the influence of the applied current density and the supporting electrolyte (NaCl or Na2SO4) on methiocarb degradation and toxicity reduction were assessed. Electrooxidation treatment presented a remarkable efficiency in methiocarb complete degradation and a high potential for reducing the undesirable ecological effects of this priority substance. The reaction rate followed first-order kinetics in both electrolytes, being more favorable in a chloride medium. In fact, the presence of chloride increased the methiocarb removal rate and toxicity reduction and favored nitrogen removal. A 200× reduction in the acute toxicity towards D. magna, from 370.9 to 1.6 toxic units, was observed for the solutions prepared with NaCl after 5 h treatment at 100 A m−2. An increase in the applied current density led to an increase in toxicity towards D. magna of the treated solutions. At optimized experimental conditions, electrooxidation offers a suitable solution for the treatment and elimination of undesirable ecological effects of methiocarb contaminated industrial or agricultural wastewaters, ensuring that this highly hazardous pesticide is not transferred to the aquatic environment

Frailty syndrome, biomarkers and environmental factors – A pilot study

Frailty is an age-related syndrome expected to increase over the next decades. This syndrome has been identified to be the most common condition leading to disability, institutionalisation and death in the elderly. The aim of this pilot study is to investigate a possible link between frailty status, biomarkers and environmental exposures. A group of 71 older adults (≥65 years old) was engaged in this study. The study population was classified as 45.1% robust, 45.1% pre-frail and 9.8% frail. A significant higher prevalence of second-hand smokers was found in the pre-frail group when compared to robust. Furthermore, a higher prevalence of robust individuals was found among those consuming home-produced vegetables and water from well/springs. Significant differences were found between data collected in a lifetime exposure questionnaire (LTEQ) and the levels of genotoxicity endpoints and the mercury levels analysed regarding some exposure-related parameters, namely, smoking habits, intake of home-produced vegetables and the use of pesticides in agriculture. Understanding if the way we live(d) or worked can impact the way we age are important questions to be explored. Data obtained in this pilot study encourage further studies on this matter, exploring the role of exposures history and its impact on health

When toxicity goes circular: Isoprostanes as markers and effectors of oxidative stress.

In normal conditions, there is a dynamic equilibrium between oxidants and antioxidants in the human body; however, when there is an unbalance in this redox state, oxidative stress occurs. In an unbalanced state, the peroxidation of polyunsaturated fatty acids originates isoprostanes (IsoPs), which can be considered as markers of oxidative stress. Since oxidative stress is associated with several non-communicable chronic diseases (NCDs), IsoPs can be used as clinical biomarkers of such diseases. Patients with congestive heart failure, cystic fibrosis and chronic renal insufficiency, for example, have higher levels of IsoPs

Avaliação do potencial citotóxico de microplásticos em linhas celulares intestinais, hepáticas e neuronais

Os Microplásticos (MPs) são uma classe emergente de contaminantes, que resultam da libertação directa de pequenas partículas que constituem total ou parcialmente objetos de uso quotidiano ou da deterioração de plásticos que originalmente possuem maiores dimensões. O polietileno (PE), a poliamida (PA-nylon 12) e o policloreto de vinilo (PVC) são três polímeros muito comumente utilizados no fabrico de sacos de plástico, recipientes e utensílios domésticos, produtos de higiene pessoal, componentes automóveis e de eletrónica e materiais de construção. Devido à sua ubiquidade (resultante da extensa utilização), os seres vivos estão constantemente expostos a estes contaminantes. No caso humano, a ingestão diária de microplásticos é uma das formas mais frequentes de exposição, tornando assim fundamental avaliar a sua potencial toxicidade. Neste trabalho a citotoxicidade de PE, PA-nylon 12 e PVC foram avaliadas em três linhas celulares distintas: células do intestino (Caco-2), do fígado (HepG2) e neurónios (N27). De uma forma geral, os microplásticos testados apresentaram toxicidade para as linhas celulares N27 e HepG2, com exceção do PE nesta última. Por outro lado, para as células Caco-2 não foram registadas reduções significativas na viabilidade celular

Avaliação toxicológica de lixiviados de aterro sanitário tratados usando o crustáceo de água doce Daphnia magna.

Os resíduos sólidos urbanos, gerados em grande escala pela sociedade moderna, precisam de ser corretamente descartados por forma a mitigar o seu impacto ambiental e na saúde pública. Estes resíduos são normalmente depositados em aterros sanitários, e, consequentemente, são gerados lixiviados altamente tóxicos que precisam de ser tratados. Este trabalho tem como objetivo avaliar a eficácia de diferentes tratamentos eletroquímicos na redução da toxicidade de um concentrado de lixiviado de aterro sanitário. O concentrado de lixiviado, resultante da aplicação de um processo de osmose inversa, foi tratado por processos eletroquímicos combinados, eletrocoagulação (EC) seguida de eletro-Fenton (EF) com diferentes intensidades de corrente e com diferentes concentrações iniciais de ferro. A eficácia do tratamento na diminuição da toxicidade foi avaliada através de ensaios de toxicidade aguda com o organismo modelo Daphnia magna. Os resultados obtidos mostraram que os ensaios de EF realizados à densidade de corrente mais alta (200 A m-2) e com uma concentração de Fe inferior (60 mg L-1) permitiram uma diminuição da toxicidade inicial de 61,305 unidades tóxicas (UTs) para 33,195 UTs, correspondente a uma redução da toxicidade de cerca de 46

Assessment of table olives' organoleptic defect intensities based on the potentiometric fingerprint recorded by an electronic tongue

Table olives are prone to the appearance of sensory defects that decrease their quality and in some cases result in olives unsuitable for consumption. The evaluation of the type and intensity of the sensory negative attributes of table olives is recommended by the International Olive Council, although not being legally required for commercialization. However, the accomplishment of this task requires the training and implementation of sensory panels according to strict directives, turning out in a time-consuming and expensive procedure that involves a degree of subjectivity. In this work, an electronic tongue is proposed as a taste sensor device for evaluating the intensity of sensory defects of table olives. The potentiometric signal profiles gathered allowed establishing multiple linear regression models, based on the most informative subsets of signals (from 24 to 29 recorded during the analysis of olive aqueous pastes and brine solutions) selected using a simulated annealing meta-heuristic algorithm. The models enabled the prediction of the median intensities (R2 ≥ 0.942 and RMSE ≤ 0.356, for leave-one-out or repeated K-fold cross-validation procedures) of butyric, musty, putrid, winey-vinegary, and zapateria negative sensations being, in general, the predicted intensities within the range of intensities perceived by the sensory panel. Indeed, based on the predicted mean intensities of the sensory defects, the electrochemical-chemometric approach developed could correctly classify 86.4% of the table olive samples according to their trade category based on a sensory panel evaluation and following the International Olive Council regulations (i.e., extra, 1st choice, 2nd choice, and olives that may not be sold as table olives). So, the satisfactory overall predictions achieved demonstrate that the electronic tongue could be a complementary tool for assessing table olive defects, reducing the effort of trained panelists and minimizing the risk of subjective evaluations.This work was financially supported by Project POCI-01-0145-FEDER-006984—Associate Laboratory LSRE-LCM, by Project UID/QUI/00616/2013 —CQ-VR, and UID/AGR/00690/ 2013—CIMO, all funded by Fundo Europeu de Desenvolvimento Regional (FEDER) through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI) and by national funds through Fundação para a Ciência e a Tecnologia (FCT), Portugal. Strategic funding of UID/BIO/04469/2013 unit is also acknowledged. Nuno Rodrigues thanks FCT, POPH-QREN, and FSE for the Ph.D. Grant (SFRH/BD/104038/2014).info:eu-repo/semantics/publishedVersio

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente