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1.
Aquat Toxicol ; 261: 106629, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37459717

RESUMO

Lithium (Li) is present in many modern technologies, most notably in rechargeable batteries. Inefficient recycling strategies for electronic waste containing this element may result in its release into aquatic systems, which may induce harmful effects on wildlife. The present study evaluated the effect of Li contamination on the gastropod Tritia reticulata exposed to different concentrations of Li (100, 200, 500 and 1000 µg L-1) for 21 days. Biochemical analyses showed that this species was not significantly affected by this contaminant at the cellular level, as no significant differences were observed in terms of metabolism, oxidative stress, and neurotoxicity. Results further revealed that snails attempted to avoid Li accumulation by burying in the sediment at a faster rate when exposed to the highest concentrations (500 and 1000 µg L-1). More research is needed to fully assess the response of T. reticulata to Li contamination, such as investigating longer exposure periods or other endpoints.


Assuntos
Lítio , Caramujos , Poluentes Químicos da Água , Animais , Lítio/toxicidade , Lítio/metabolismo , Estresse Oxidativo , Caramujos/fisiologia , Poluentes Químicos da Água/toxicidade , Resíduo Eletrônico
2.
Sci Total Environ ; 847: 157634, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35905959

RESUMO

The circular economy is based on the maximum use of resources by reducing, reusing, and recycling the elements used. Currently, the items littered most frequently in the world are cigarettes butts (CB) as these debris are freely disseminated in the marine habitat, they are generally difficult to collect and very complex to recycle. Litter CB is a great social problem that generates excessive economic costs and serious environmental problems. CB is also not biodegradable and highly toxic to marine organisms and presents a distinctive mixture of physical and chemical contamination. However, little research has been done on the management and recycling of this dangerous waste. Several proposals have been made to incorporate this waste into high-volume articles of direct production or recycling, but collection logistics are lacking since the current system is inefficient, in addition to the poor environmental behaviour of citizens. This work presents a current synthesis of the CB problem from all its possible aspects in order to have a global vision of the life cycle of the CB, indicating both the known and the gaps in the knowledge of each of them, and intends to give a general outline of the steps to follow to try to end such a worrying problem at the global level.


Assuntos
Produtos do Tabaco , Gerenciamento de Resíduos , Organismos Aquáticos , Reciclagem
3.
Environ Sci Pollut Res Int ; 29(43): 64745-64755, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35476271

RESUMO

The most important use of lithium (Li) is in rechargeable batteries. The growing use of Li, incorrect disposal of Li-based applications, and inefficient recycling strategies for their elimination will result in the release of this metal into the aquatic systems. Alongside with the impacts caused by pollutants, organisms in coastal ecosystems are also facing environmental changes as those related with climate change scenarios, namely, seawater temperature rise. In this context, the present study aimed to evaluate the influence of temperature on Li toxicity, using the Nassariid gastropod Tritia neritea as model species. Metabolism and oxidative stress related biomarkers were evaluated after a 28-day exposure period. The results demonstrated that temperature enhanced the toxic impacts of Li, most probably due to snail increased sensitivity when under warming conditions. As a consequence of inefficient antioxidant and biotransformation capacity, lipid peroxidation was observed in Li-contaminated snails at 21 ºC, demonstrating a significant interaction between both factors. Regarding snails' metabolic capacity, Li did not affect snails, but a clear decrease on their metabolism was observed at increased temperature (with or without Li) which may limit snail defense capacity. Overall, the present findings demonstrated the impacts derived from Li towards marine intertidal gastropods, evidencing enhanced threats under predicted warming conditions. Considering the role of T. neritea in the ecosystem functioning, impacts on this species may greatly affect other populations and eventually the entire community.


Assuntos
Lítio , Poluentes Químicos da Água , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Ecossistema , Lítio/toxicidade , Caramujos/metabolismo , Temperatura , Poluentes Químicos da Água/toxicidade
4.
Environ Pollut ; 293: 118549, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34813884

RESUMO

Ocean acidification (OA) has received more attention in the marine research community in recent years than any other topic. Excess carbon dioxide makes the ocean more acidic, threatening marine ecosystems. There has been little research on the impact of OA on crustaceans, particularly on their physiological and potential ecosystem-level consequences. Thus, we investigated the impacts of OA on the physiological and biochemical characteristics of the estuarine amphipod Ampelisca brevicornis. Ovigerous amphipods were harvested from nature and maintained in the laboratory to produce juveniles, which were then further reared to obtain the mature adults (F0) and successive offspring (F1). For this study, four pH treatments (pH 8.1, 7.5, 7.0, and 6.5) mimicking future OA were evaluated to understand the physiological and biochemical effects on the organisms. The findings of this study suggest that A. brevicornis is more vulnerable to OA than was previously established in short-term trials. The survival was significantly reduced as pH decreased over time and a significant interaction between pH and time was observed. Survival was higher in F1 than in F0 juveniles and vice versa in terms of growth. Animal's physiological responses such as growth, burrowing behavior, locomotor activity, swimming speed, ventilation rate and reproductive performance were negatively influenced by acidification. These physiological characteristics can be linked to the oxidative stress induced by global change conditions because excess of free radicals degrade cell functioning, affecting species' biochemical and physiological performance. These alterations may have long-term negative impacts, with ecological consequences. The results of this study provide baseline information regarding the effect of OA on this keystone crustacean that may be useful in simulating the impacts of OA to develop different conceptual models for a better understanding of the consequences and implications of climate change in the future for managing marine ecosystems.


Assuntos
Anfípodes , Animais , Ecossistema , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar
5.
Environ Res ; 199: 111332, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34004168

RESUMO

In this study we investigated the independent and synergistic effects of lithium (Li, 0.08 mM) contamination and the rising seawater temperature (21 °C; control- 15 °C) on survival and trophic interactions (foraging behaviour, success, search time, carrion preference, feeding time, and tissue consumption-the dry weight basis) of the opportunistic intertidal scavenger Tritia neritea. Trophic interactions were assessed in a two-choice test using a Y-maze design using the same amount of two carrion species (Solen marginatus and Mytilus galloprovincialis) given to all snails simultaneously. Lithium pollution and synergestic warming have the effect of reducing the survival rate of T. neritea, triggering potential global change scenarios. The foraging behaviour of T. neritea under Li-contaminated conditions was characterised by a decrease in the snail's effectiveness in finding a carrion. Lithium changes the feeding behaviour as well as increasing the time it takes for snails to reach their food. T. neritea did not show preference for any of the carrion species offered in controls, but a shift in feeding behaviour towards more energetic carrion under Li contamination which may indicate a strategy to compensate for the greater energy expenditure necessary to survive. There were no differences in feeding time at the different treatments and regardless of the treatment tested T. neritea consumed more mussels tissue probably due to its greater palatability. Results showing foraging modifications in an intertidal scavenger mollusc in global change scenarios indicate potential changes in complex trophic interactions of marine food webs.


Assuntos
Lítio , Mytilus , Animais , Cadeia Alimentar , Água do Mar , Caramujos
6.
Sci Total Environ ; 750: 142031, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33182219

RESUMO

It is currently assumed that climate change related factors pose severe challenges to biodiversity maintenance. This paper assesses the multi-stressor effects of elevated temperature (15 °C as control, 25 °C as elevated) and CO2 levels (pH 8.1 as control, 7.5 and 7.0 representing acidifying conditions) on the physiological (survival and regenerative capacity), behavioral (feeding and burrowing activities), and biochemical changes (metabolic capacity, oxidative status and biotransformation mechanisms) experienced by the keystone polychaete Hediste diversicolor. Temperature rise enlarged the adverse effect of marine acidification on the survival of H. diversicolor, delayed the beginning of the excavation activity, enhancing the negative effects that pH decrease had in the burrowing behavior of this polychaete. Additionally, regardless of the temperature, exposure of H. diversicolor to acidification results in a reduction in the feeding rate. It is the first time that this decreased feeding capacity is found related to seawater acidification in this species. The healing of the wound and the blastemal formation were retarded due to these two climatic factors which hinder the regenerative process of polychaetes. These vital physiological functions of H. diversicolor can be related to the oxidative stress induced by climate change conditions since free radicals overproduced will impair cells functioning, affecting species biochemical and physiological performance, including feeding and tissue regeneration. The present results also demonstrated that although polychaetes' metabolic capacity was enhanced under stress conditions, organisms were still able to increase or maintain their energy reserves. Our findings are of major environmental relevance considering that predicted climate change conditions will affect species vital and ecological and physiological capacities. These can be translated into shrinking not only at the individual and population level but also in microbial and endofaunal diversities, in the detritus processing in estuaries and biogeochemical cycles at the ecosystem level. Thus the conservation of H. diversicolor populations is vital for the normal functioning of estuarine mudflat ecosystems.


Assuntos
Poliquetos , Poluentes Químicos da Água , Animais , Mudança Climática , Ecossistema , Água do Mar
7.
Zookeys ; (791): 71-95, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30386154

RESUMO

Spaniomolgus is a symbiotic genus of copepods of the poecilostomatoid family Rhynchomolgidae and is known to be associated with shallow-water reef-building hermatypic corals. Three species of this genus were previously found only in washings of Acropora and Stylophora in northern Madagascar. Four coral morphotypes of Stylophorapistillata (Pocilloporidae) were collected by SCUBA at 1 to 28 m depth in five sites in the Saudi Arabian Red Sea in 2013. Copepods found on these colonies were studied using light, confocal and scanning electron microscopy. Five new, and one known, species of the genus Spaniomolgus were discovered in washings and inside the galls of the hermatypic coral S.pistillata. The description of these new species (Spaniomolgusglobus sp. n., S.stylophorus sp. n., S.dentatus sp. n., S.maculatus sp. n., and S.acutus sp. n.) and a key for the identification of all of its congeners is provided herein.

8.
Zootaxa ; 4174(1): 259-273, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27811801

RESUMO

Asterocheres Boeck, 1860 is the largest genus in the family Asterocheridae and includes approximately 96 nominal species. Nevertheless, according to Kim (2010), the current assignment of twelve of these species to Asterocheres is debatable, and fifteen species are too incompletely described for reliable comparisons to be made. In this paper, two species, A. corneliae Schirl, 1973 and A. boeckii (Brady, 1880), are redescribed and compared with their congeners. As a result of the comparison between A. boeckii and A. fastigatus Kim, 2010, a new genus, Kimcheres, is erected to accommodate the only species of Asterocheres displaying the armature formula (0-1) on the second endopodal segment of leg 4. The taxonomic position of A. longisetosus Nair & Pillai, 1984, considered as species inquirenda by Kim (2010), is discussed. Examination of the original description and illustrations, especially the antennules and the mandible, casts doubts on the validity of the species.

 Asterocheres Boeck, 1860 is the largest genus in the family Asterocheridae and includes approximately 96 nominal species. Nevertheless, according to Kim (2010), the current assignment of twelve of these species to Asterocheres is debatable, and fifteen species are too incompletely described for reliable comparisons to be made. In this paper, two species, A. corneliae Schirl, 1973 and A. boeckii (Brady, 1880), are redescribed and compared with their congeners. As a result of the comparison between A. boeckii and A. fastigatus Kim, 2010, a new genus, Kimcheres, is erected to accommodate the only species of Asterocheres displaying the armature formula (0-1) on the second endopodal segment of leg 4. The taxonomic position of A. longisetosus Nair & Pillai, 1984, considered as species inquirenda by Kim (2010), is discussed. Examination of the original description and illustrations, especially the antennules and the mandible, casts doubts on the validity of the species.


Assuntos
Copépodes/anatomia & histologia , Copépodes/classificação , Animais , Copépodes/fisiologia , Ectoparasitoses/parasitologia , Ectoparasitoses/veterinária , Europa (Continente) , Feminino , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Masculino
9.
Chemosphere ; 156: 272-279, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27179245

RESUMO

The carbon capture and storage (CCS) technologies that were proposed to mitigate environmental problems arising from anthropogenic CO2 emissions, also have potential environmental risks. An eventual CCS leak might induce very low pH values in the aquatic system. Due to the lack of knowledge of long-term CO2 exposures with very low pH values, this study aims to know the effects and consequences of such a situation for zooplankton, using the Daphnia magna experimental model. A CO2 injection system was used to provide the experimental condition. A twenty-one days experiment with control and low pH treatment (pH = 7) replicates was carried out under light and temperature-controlled conditions. Survival, individual growth, RNA:DNA ratio, and neonates production were analysed during the aforementioned period. No differences on survival (except last day), individual growth and RNA:DNA ratio were observed between both control and low pH treatments. However, clear differences were detected in neonates production and, consequently, in population growth rates and secondary production. The observed differences could be related with an energy allocation strategy to ensure individual survival but would have ecological consequences affecting higher trophic levels.


Assuntos
Dióxido de Carbono/análise , Dióxido de Carbono/toxicidade , Daphnia/crescimento & desenvolvimento , Ecologia , Animais , Sequestro de Carbono , Daphnia/efeitos dos fármacos , Daphnia/genética , Recuperação e Remediação Ambiental , Concentração de Íons de Hidrogênio , Análise de Sobrevida , Fatores de Tempo
10.
Zootaxa ; 3827(4): 542-58, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25081176

RESUMO

The present paper reviews the material of three species of Asterocheres Boeck 1859 deposited in four different Zoological European museums as part of the ongoing taxonomical revision of this genus. Asterocheres sarsi Bandera & Conradi 2009, the species described by Sars in 1915 as Ascomyzon latum (Brady 1880) and lately recognized as a distinct species by Bandera and Conradi in 2009 is fully described in this paper from material collected by Sars in Norway in 1915 and deposited in The Natural History Museum of the University of Oslo. Asterocheres complexus Stock, 1960 which has been sometimes confused with A. sarsi is redescribed from material collected by Stock in France in 1959 and deposited in the Zoological Museum of the University of Amsterdam. Furthermore, a new species, previously misidentified as A. suberitis Gieisbrecht 1897, from the Norman`s collection of The Natural History Museum of London, is described as A. eugenioi, new species. These three species, A. complexus, A. eugenioi, and A. sarsi share the general appearance of body thanks to the pointed posterolateral angle of the epimeral area of somite bearing leg 3, sometimes slightly produced into backwardly directed processes, and somite bearing leg 4 largely concealed under somite bearing leg 3.


Assuntos
Copépodes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Copépodes/anatomia & histologia , Copépodes/crescimento & desenvolvimento , Ecossistema , Feminino , Masculino , Museus , Tamanho do Órgão
11.
Environ Toxicol Chem ; 18(10): 2275-2282, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29857629

RESUMO

A method of DNA profiling using the random amplified polymorphic DNA (RAPD) was used to assess toxicant-induced DNA effects in laboratory populations of Daphnia magna exposed to varying concentrations of the genotoxic hydrocarbon benzo[a]pyrene. These effects, represented by changes in the RAPD profiles, were compared with a number of key ecological fitness parameters (age-specific survival, age-specific fecundity, net reproductive rate, and intrinsic rate of population increase). Not only was the RAPD profiling method shown to be a rapid and reproducible assay of toxicant-induced DNA effects, but the qualitative measure of genomic template stability compared favorably with the traditional indices of fitness. The RAPD profiles, however, exhibited higher sensitivity in detecting toxic effects. The significance of these findings for future ecotoxicological studies is discussed.

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