Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Environ Manage ; 354: 120315, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350278

RESUMO

Annually, the Mediterranean region attracts around one-third of the global coastal tourism, which is acknowledged as a substantial contributor to plastic pollution. Coastal municipalities mitigate this through periodic sand and shore cleaning. However, the efficacy of these measures remains uncertain. In this study, the occurrence of MPs (10 µm-5 mm) in sand from seven different, regularly cleaned, touristic beaches of the coastline of Valencia province (E Spain) was assessed. Two different sampling campaigns were performed in winter and in summer (2022) to compare the results and understand the influence of the high touristic activity, as well as, the efficiency of the measures taken against MPs pollution. The methodology used was designed specifically for the matrix and employed density separation using a Sediment Microplastic Isolation (SMI) Unit. In addition to conventional visual inspection and ATR-FTIR, automatic quantification and identification of the polymers of lower size was performed by µFTIR. The average MPs concentration in the summer (339 ± 92 MP kg-1 by stereomicroscopy and 339 ± 189 MP kg-1 by µFTIR) was significantly higher than in the winter (71 ± 92 MP kg-1 and 143 ± 85 MP kg-1) (p < 0.05). The combination of these analytical tools provides comprehensive information about the MPs present in beach sand. Fibers were the most abundant form of MPs, while most of the polymers analyzed were polyethylene (PE) and halogenated polystyrene (Cl-PS and Br-PS) with food packaging, swimming equipment and fishing nets being their most probable sources. Ecological risk assessment was performed through the Pollution Load Index (PLI), the Hazardous Index (HI) and the Risk Quotient (RQ), with the results indicating potential risk that ranges from moderate to high depending on the applied approach.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Areia , Espanha , Turismo , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Polímeros , Medição de Risco , Sedimentos Geológicos
2.
J Hazard Mater ; 465: 133274, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38128229

RESUMO

Uco valley (Mendoza, Argentina) suffers the concomitant effect of climate change, anthropic pressure and water scarcity. Moreover chemical pollution to aquatic ecosystems could be another pressuring factor, but it was not studied enough to the present. In this sense, the aim of this study was to assess the occurrence of pesticides, pharmaceuticals and personal care products (PPCPs) in aquatic ecosystems of the Uco Valley and to perform an ecological risk assessment (ERA). The presence of several insecticides (mainly neonicotinoids), herbicides (atrazine, diuron, metolachlor, terbutryn) and fungicides (strobilurins, triazolic and benzimidazolic compounds) in water samples in two seasons, related to crops like vineyards, garlic or fruit trees was associated to medium and high-risk probabilities for aquatic biota. Moreover, PPCPs of the group of non-steroidal anti-inflammatory drugs, parabens and bisphenol A were detected in all the samples and their calculated risk quotients also indicated a high risk. This is the first record of pesticides and PPCPs with an ERA in this growing agricultural oasis. Despite the importance of these findings in Uco Valley for decision makers in the region, this multilevel approach could bring a wide variety of tools for similar regions in with similar productive and environmental conditions, in order to afford actions to reach Sustainable Development Goals. SYNOPSIS: Aquatic ecosystems in arid mountain regions are threatened worldwide. This study reports relevant data about chemical pollution in Central Andes, which could be a useful tool to enhance SDGs' accomplishment.


Assuntos
Cosméticos , Herbicidas , Praguicidas , Poluentes Químicos da Água , Praguicidas/análise , Ecossistema , Monitoramento Ambiental , Herbicidas/análise , Cosméticos/análise , Medição de Risco , Poluentes Químicos da Água/análise , Preparações Farmacêuticas
3.
J Hazard Mater ; 416: 125747, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-33819645

RESUMO

In this study, water of the channels and ponds that conduct residual water in two most important cities of Saudi Arabia were assessed to ascertain the influence of the population on the occurrence and pollution characteristics of microplastics (MPs) (> 20 µm in size). Riyadh has 7.6 million inhabitants and is an urban city even though also have industry while Al-Jubail has only 0.78 and is the biggest industrial city. MPs showed an average of 3.2 items/L in Riyadh and 0.2 items/L in Al-Jubail showing a statistically significant difference between both cities. Sampling with a Turton Tow Net of 20 µm mesh, fibers were dominant in all sites (60%). MPs size was mainly distributed between 80 and 250 µm (60%), and their major colors were white (40%), red (25%) and blue (20%). Infrared spectral analysis revealed that most of the selected particles were identified as MPs of polypropylene and polyethylene (48.3%). The risk assessment was carried out using both the hazard index (HI) and the pollution load index (PLI). The results showed that, in this case, the decisive index is the PLI since the main difference in the MPs characteristics between the two cities is their concentration.


Assuntos
Microplásticos , Poluentes Químicos da Água , Cidades , Monitoramento Ambiental , Plásticos , Arábia Saudita , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Food Chem Toxicol ; 125: 305-312, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30654098

RESUMO

Coffee is a highly consumed beverage with many putative beneficial health effects, however these often come from observational studies. In the current work, a lightly roasted coffee extract that has previously been reported to exhibit potent antioxidant properties was administered for two weeks in rats to examine the potential improvement of blood and tissue redox status. The dose was equivalent to a moderate human daily consumption. According to our results, coffee exerted beneficial effects in all tissues mainly by increasing reduced glutathione (GSH) levels. Interestingly, the brain was the most significantly affected tissue, while the gastrointestinal tract, the main metabolic organs and the quadriceps were also benefited. In addition, protein and lipid oxidation was reduced in several tissues. The observed increase in GSH was attributed to increased levels of the rate-limiting enzyme in its biosynthesis pathway, namely γ-glutamylcysteine ligase both in the protein and gene levels. Overall, moderate coffee consumption showed beneficial short term effects in rat tissues by stimulating parts of the endogenous antioxidant mechanisms.


Assuntos
Antioxidantes/farmacologia , Café/química , Glutationa/metabolismo , Extratos Vegetais/farmacologia , Animais , Coffea/química , Glutamato-Cisteína Ligase/genética , Masculino , Oxirredução , RNA Mensageiro/genética , Ratos Wistar , Superóxido Dismutase/genética , Regulação para Cima/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA