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2.
Environ Pollut ; 333: 121932, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37336348

RESUMO

The presence of plastic in our environment is having a massive impact on today's marine biota. Whales and dolphins are becoming sentinels of litter pollution as plastic entanglement and ingestion affect them with unknown consequences. Although information exists about this anthropogenic interaction, the compilation of this data on metastudies is difficult due to the use of varied methodologies. A combination of our own data as well as a review of historical data was used to complete an extensive study of how cetaceans are interacting with macro and micro-litter at a global level. Here, we identify the plastic uptake by two cetacean families: Ziphiidae and Delphinidae, thus allowing for a better understanding in order to offer a global overview of their current status. Additionally, analysis was run on the plastic found in the digestive contents of stranded specimens of two Cuvier's beaked whales and fourteen striped dolphins in the Alboran Sea, in the Western Mediterranean, a hotspot for marine megafauna. Out of 623 stranded cetaceans from datasets, beaked whales displayed the highest concentration of macro, meso and microplastic in the Western Pacific Ocean. Regarding striped dolphins, Eastern Spain was the location with the highest plastic ingestion. Moreover, deep divers such as beaked whales ingested more plastic than striped dolphins which could be as a consequence of their feeding behavior or habitat. Thus, this overview provides useful information concerning conservation issues on how cetacean hotspots are highly affected by marine plastic ingestion.


Assuntos
Golfinhos , Stenella , Animais , Baleias , Plásticos/análise , Ingestão de Alimentos
3.
Sci Total Environ ; 850: 158025, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35973533

RESUMO

The presence of plastic in the environment has become a major problem for marine ecosystems. The identification of the global micro and mesoplastic uptake by commercial fish populations may allow for a better understanding of their impact. This study aims to determine the presence and composition of plastic in two pelagic fish (Engraulis encrasicolus and Scomber scombrus) and two demersal species (Scyliorinus canicula and Mullus barbatus) from the Alboran Sea (western Mediterranean) to quantify the relationship between plastic prevalence and the environment and feeding behavior in the selected fish species. Samples of these four fish species from sites in the Alboran Sea were studied for ingested plastics. These localized samples were also compared to published values which covered a broader geographical range. Samples from the Alboran Sea study sites showed that the predominant fiber color was black and the predominant plastic polymers were polyethylene and cellulose. At the Alboran Sea study site the highest plastic occurrence was found in S. scombrus, whereas in the published literature the highest occurrence of plastics in digestive tracts was found in E. encrasicolus. The general prevalence of marine plastic pollution and levels of macro- and micro-plastic ingested by commercial fish species in this study support the idea that quantifying plastic presence and composition may be essential to understanding potential impacts on marine ecosystems.


Assuntos
Perciformes , Poluentes Químicos da Água , Animais , Celulose , Ecossistema , Monitoramento Ambiental , Peixes , Mar Mediterrâneo , Microplásticos , Plásticos , Polietileno/análise , Poluentes Químicos da Água/análise
4.
Glob Chang Biol ; 27(4): 728-737, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33111371

RESUMO

The presence of plastic in the environment is generating impacts on all habitats and has become a major global problem in marine megafauna. Macroplastics can cause entanglement, ingestion and loss of suitable habitats. In addition to entanglement problems, there is evidence that plastics are entering the food web through ingestion by marine organisms, which could ultimately be affecting humans. Much of the available information on the impact of plastic in biota is scattered and disconnected due to the use of different methodologies. Here, we review the variety of approaches and protocols followed to assess macro- and microplastic ingestion in marine vertebrates such as sea turtles, cetaceans and fishes in order to offer a global overview of their current status. The analysis of 112 studies indicates the highest plastic ingestion in organisms collected in the Mediterranean and Northeast Indian Ocean with significant differences among plastic types ingested by different groups of animals, including differences in colour and the type of prevalent polymers. In sea turtles, the most prevalent types of plastics are white plastics (66.60%), fibres (54.54%) and LDPE polymer (39.09%); in cetaceans, white macro- and microplastics (38.31%), fibres (79.95%) and PA polymer (49.60%); and in fishes, transparent plastics (45.97%), fibres (66.71%) and polyester polymer (36.20%). Overall, clear fibre microplastics are likely the most predominant types ingested by marine megafauna around the globe.


Assuntos
Tartarugas , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Ingestão de Alimentos , Monitoramento Ambiental , Cadeia Alimentar , Oceano Índico , Plásticos , Poluentes Químicos da Água/análise
5.
J Environ Manage ; 245: 245-254, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154171

RESUMO

The aim of the present study was to investigate the kinetics of methylparaben (MPB) and butylparaben (BPB) removal, two emerging pollutants with possible endocrine disrupting effects, from agricultural soil with and without amendment with compost from sewage sludge used as biostimulant. Compound removal is explained by a first-order kinetic model with half-life times of 6.5/6.7 days and 11.4/8.2 days, in presence/absence of compost, for MPB and BPB respectively. % R2 for the fitted model were higher than 96% in all cases. Additionally, isolation of bacteria capable to grow using MPB or BPB as carbon source was also carry out. Laboratory tests demonstrated the ability of these bacteria to biodegrade MPB and BPB from culture media in more than 95% in some cases. These strains showed high ability to biodegrade the compounds. Ten isolates, most of them related to Gram positive bacteria of the genus Bacillus, were identified by 16S rRNA gene sequencing. The study of the enzymatic activities of the isolates revealed both esterase (C4) and esterase-lipase activities.


Assuntos
Poluentes do Solo , Solo , Bactérias , Parabenos , RNA Ribossômico 16S , Esgotos , Microbiologia do Solo
6.
Obes Surg ; 27(12): 3330-3332, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28924918

RESUMO

The molecular mechanisms implicated in pronounced weight loss and metabolic benefits after bariatric surgery are still unknown. Adipocyte phenotype and metabolism have not been entirely explored. However, some features of adipocyte function have been studied, such as adipocyte size and inflammation, which are both reduced after bariatric surgery. Adipocyte fat metabolism, which is partly regulated by leptin, is likely modified, since adipocyte area is decreased. Here, we show that leptin receptor expression is increased, while adipocyte size is decreased 8 months after Roux-en-Y gastric bypass. Thus, adipocyte function is possibly modified by improved leptin signaling after bariatric surgery.


Assuntos
Adipócitos/patologia , Derivação Gástrica , Obesidade Mórbida/cirurgia , Receptores para Leptina/metabolismo , Gordura Subcutânea/metabolismo , Gordura Subcutânea/patologia , Adipócitos/metabolismo , Adulto , Tamanho Celular , Feminino , Derivação Gástrica/reabilitação , Humanos , Leptina/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/metabolismo , Obesidade Mórbida/patologia , Redução de Peso/fisiologia
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