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1.
Environ Sci Technol ; 55(14): 10012-10024, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34218659

RESUMO

We aimed to identify patterns in the internal distribution of persistent organic pollutants (POPs) and assess contributing factors using sea turtles and their offspring as a case study of a long-lived wildlife species. We systematically synthesized 40 years of data and developed a lipid database to test whether lipid-normalized POP concentrations are equal among tissues as expected under steady state for lipophilic compounds. Results supported equal partitioning among tissues with high blood flow or perfusion including the heart, kidney, muscle, and lung. Observed differences in the brain, fat, and blood plasma, however, suggest the physiological influence of the blood-brain barrier, limited perfusion, and protein content, respectively. Polybrominated diphenyl ethers partitioned comparably to legacy POPs. Polycyclic aromatic hydrocarbons, meanwhile, partitioned more into the lung, colon, and muscle compared to the liver under chronic and acute field exposure. Partitioning ratios of individual POPs among tissues were significantly related to the lipophilicity of compounds (as estimated by Kow) in half of the observed cases, and significant differences between juveniles and adults underscore physiological differences across life stages. The comprehensive tissue partitioning patterns presented here provide a quantitative basis to support comparative assessments of POP pollution derived from biomonitoring among multiple tissues.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Tartarugas , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Poluentes Ambientais/análise , Éteres Difenil Halogenados/análise , Poluentes Orgânicos Persistentes
2.
Sci Total Environ ; 866: 161400, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36610621

RESUMO

The high accumulation potential of estuaries for plastics, particularly microplastics, poses a threat to the high societal value and biodiversity they provide. To support a spatially refined evaluation of the risk that microplastic pollution poses to fauna utilizing estuarine sedimentary habitats, we investigated the distribution of microplastics (lower limit of quantification, LOQ = 62 µm) at the sediment surface of two dominant habitats, and subsequently compared microplastic burdens between two crabs species utilizing these habitats. Microplastics were dominated by low density polyolefins (45-50 %), comparable to the polymer composition of macroplastics. The vast majority (99 %) of microplastics were ≤1 mm, and increased exponentially (with an exponent of 2.7) in abundance at smaller sizes, hinting at three-dimensional fragmentation. Our results suggest that the presence of vegetation needs to be accounted for in risk assessments with small microplastics (≥62 µm and ≤1 mm) on average 2.6 times more prevalent within reed beds compared to mudflats. Additionally, sediment properties also play a role with an exponential decrease in small microplastic abundance at coarser sediments, increased organic matter content, and decreased water content. These results suggest that at specific locations, such as the study area, local sources can provide a substantial contribution to microplastic contamination. To translate these habitat- and site-specific differences into a risk assessment relevant for macroinvertebrates, ecological traits such as differences in feeding modes should be accounted for, as we found substantial differences in both size and abundance of microplastics in gastrointestinal tracts of two crab species, Chiromantes dehaani and Chasmagnathus convexus, with different feeding modes.


Assuntos
Braquiúros , Poluentes Químicos da Água , Animais , Microplásticos , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos , Ecossistema , Biodiversidade
3.
Mar Environ Res ; 192: 106252, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37944348

RESUMO

Estuaries contain some of the highest concentrations of accumulated microplastics (MPs) that can be ingested by abundant deposit-feeding crabs. We investigate MPs in gill, hepatopancreatic, and gastrointestinal tissues of seven intertidal crab species in Kokubu River, Kochi, Japan. By applying a reliable method that considers limits of detection and quantification, we report MPs in 63 of 116 crabs (>50%), with a mean of 3.2 MPs individual-1. Concentrations are greatest in gastrointestinal tracts (62.15%), suggesting that feeding is the main route for MP uptake. PET is the dominant polymer (44%), and fragments are the dominant shape (50%-77%). A greater MPs burden g-1 body weight is reported for deposit-feeding small ocypodid crabs than for larger herbivorous/omnivorous grapsoid crabs. Factors possibly influencing MP uptake by crabs include feeding habit, crab size, and ambient MP composition.


Assuntos
Braquiúros , Poluentes Químicos da Água , Animais , Microplásticos , Estuários , Plásticos , Japão , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Ingestão de Alimentos
4.
MethodsX ; 10: 101987, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36624730

RESUMO

The inability to quantitatively integrate scattered data regarding potential threats posed by the increasing total amount and diversity of chemical substances in our environment limits our ability to understand whether existing regulations and management actions sufficiently protect wildlife. Systematic literature reviews and meta-analyses are great scientific tools to build upon the current push for accessibility under the Open Science and FAIR movements. Despite the potential of such integrative analyses, the emergence of innovative findings in wildlife ecology and ecotoxicology is still too rare relative to the potential that is hidden within the entirety of the available scattered data. To promote the reuse of wildlife ecotoxicology data, we propose the ATTAC workflow which comprises five key steps (Access, Transparency, Transferability, Add-ons, and Conservation sensitivity) along the chain of collecting, homogenizing, and integrating data for subsequent meta-analyses. The ATTAC workflow brings together guidelines supporting both the data prime movers and re-users. As such, the ATTAC workflow could promote an open and collaborative wildlife ecotoxicology able to reach a major objective in this applied field, namely, providing strong scientific support for regulations and management actions to protect and preserve wildlife species.

5.
Global Health ; 7: 16, 2011 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21595940

RESUMO

BACKGROUND: In March 2009, the Task Force for Innovative International Financing for Health Systems recommended "a health systems funding platform for the Global Fund, GAVI Alliance, the World Bank and others to coordinate, mobilize, streamline and channel the flow of existing and new international resources to support national health strategies." Momentum to establish the Health Systems Funding Platform was swift, with the World Bank convening a Technical Workshop on Health Systems Strengthening (HSS), and serial meetings organized to progress the agenda. Despite its potential significance, there has been little comment in peer-reviewed literature, though some disquiet in the international development community around the scope of the Platform and the capacity of the partners, which appears disproportionate to the available information. METHODS: This case study uses documentary analysis, participant observation and 24 in-depth interviews to examine the processes of development and key issues raised by the Platform. RESULTS: The findings show a fluid and volatile process, with debate over whether ongoing engagement in HSS by Global Fund and GAVI represents a dilution of organizational focus, risking ongoing support, or a paradigm shift that facilitates the achievement of targeted objectives, builds systems capacity, and will attract additional resources. Uncertainty in the development of the Platform reflects the flexibility of the recently formed global health initiatives, and the instability of donor commitments, particularly in the current financial climate. But implicit in the conflict is tension between key global stakeholders over defining and ownership of the health systems agenda. CONCLUSIONS: The tensions appear to have been resolved through a focus on national planning, applying International Health Partnership principles, though the global financial crisis and key personnel changes may yet alter outcomes. Despite its dynamic evolution, the Platform may offer an incremental path towards increasing integration around health systems, that has not been previously possible.

6.
Environ Pollut ; 286: 117308, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33991734

RESUMO

Despite the global occurrence of microplastic contamination on sandy beaches, evidence of microplastic distribution within beaches remains contradictory. When conflicting evidence is used to inform sampling surveys, it increases uncertainty in resulting data. Moreover, it hampers spatially explicit risk characterization of microplastic pollution to intertidal fauna. We aimed to guide sampling designs for microplastic monitoring on beaches, and to quantify macroinfauna exposure to microplastics. Microplastic abundance, quantified between 5 mm-66 µm, lacked a significant zonation across the top sediment layer of sub-terrestrial, upper and lower midlittoral, and swash zones at two sites with varying anthropogenic influence on a microtidal dissipative beach in Uruguay. Microplastic abundance decreased exponentially with increasing grain size, as revealed by Bayesian Poisson regression, although the decrease was less steep compared to prior knowledge regarding sediment - plastic interactions obtained for large (millimeter-sized) industrial pellets. Significant differences in microplastic contamination between the two sites with varying anthropogenic influence likely related to their proximity to a freshwater canal. Corresponding field measurements of body burdens of fibers and irregular particles were significantly lower for the polychaete Euzonus (Thoracophelia) furcifera, despite its preference for finer sediments with higher microplastic loads, compared to the isopods Excirolana braziliensis and Excirolana armata. Results provide critical insights toward representative sampling of microplastics within beach sites. Specifically, we caution against sampling limited to the drift line, and instead recommend: 1) reporting beach morphodynamic characteristics; 2) using clearly defined, ecologically-informed zonation schemes; and 3) accounting for sediment grain size as a covariate to normalize among reported contamination levels. The results contribute valuable baseline data toward realistic exposure landscapes relative to the sediment grain size preferences of macroinfauna, needed to inform laboratory experiments.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Teorema de Bayes , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Poluentes Químicos da Água/análise
7.
BMJ Glob Health ; 6(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34183329

RESUMO

Implementing an Ebola vaccine trial in a remote area in the Democratic Republic of the Congo (DRC), and being confronted with a dysfunctional health care system and acute unmet health needs of participants, ethical considerations were made regarding the ancillary care obligations of the sponsor and researchers. Spurred by the occurrence of non-related (serious) adverse events (NR-SAEs), the Universities of Antwerp and Kinshasa jointly developed an algorithm, accompanied by an algorithm policy. The algorithm consists of a set of consecutive questions with binary response options, leading to structured, non-arbitrary and consistent support and management for each NR-SAE. It is the result of dialogue and collaboration between the sponsor (University of Antwerp) and the principal investigator (University of Kinshasa), consultation of literature, and input of research ethics and social sciences experts. The characteristics of the project and its budgetary framework were taken into account, as well as the local socioeconomic and healthcare situation. The algorithm and related policy have been approved by the relevant ethics committee (EC), so field implementation will begin when the study activities resume in November 2021. Lessons learnt will be shared with the relevant stakeholders within and outside DRC.If NR-SAEs are not covered by a functioning social welfare system, sponsors and researchers should develop a feasible, standardised and transparent approach to the provision of ancillary care. National legislation and contextualised requirements are therefore needed, particularly in low/middle-income countries, to guide researchers and sponsors in this process. Protocols, particularly of clinical trials conducted in areas with 'access to care' constraints, should include adequate ancillary care arrangements. Furthermore, it is essential that local ECs systematically require ancillary care provisions to enhance the well-being and protection of the rights of research participants. This project was funded by the European Union's Horizon 2020 research and innovation programme, European Federation of Pharmaceutical Industries and Associations, and the Coalition for Epidemic Preparedness Innovations.


Assuntos
Vacinas contra Ebola , Doença pelo Vírus Ebola , Algoritmos , República Democrática do Congo/epidemiologia , Vacinas contra Ebola/efeitos adversos , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Universidades
8.
Environ Toxicol Chem ; 39(1): 9-29, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31560792

RESUMO

Maternal transfer of persistent organic pollutants (POPs) confronts developing embryos with a pollution legacy and poses conservation concerns due to its potential impacts unto subsequent generations. We conducted a systematic review focusing on: 1) processes of POP maternal transfer, 2) challenges and opportunities to synthesizing current knowledge on POP concentrations in eggs, and 3) a meta-analysis of patterns in current egg pollution data. Results suggest selective maternal transfer of individual compounds. These relate to biological factors such as the foraging and remigration behavior, and to the selective mobilization of POPs during vitellogenesis, such as increased diffusion limitation for lipophilic POPs and slower release and higher reabsorption of apolar POPs. A key gap relates to knowledge of further selective toxicokinetics during embryonic development, as research to date has mainly focused on initial uptake into eggs. Challenges in the synthesis of current data on egg contamination profiles relate to methodological differences, varying analytical approaches, restricted data access, and reporting transparency among studies. To increase opportunities in the use of current data, we propose best practice guidelines, and synthesize a database on POP concentrations within sea turtle eggs. The meta-analysis revealed a geographical and taxonomic bias on the West Atlantic Ocean, including the Gulf of Mexico and Caribbean Sea, with most studies conducted on green turtles. Concentrations of POPs show temporal patterns related to trends in usage, production, release, and persistence in the environment, often with regional patterns. The trophic level has the potential to influence POP patterns with higher concentrations in loggerheads compared to other species, but this is confounded by temporal and geographic trends. We argue for more mechanistically process-focused and methodologically comparable research. Environ Toxicol Chem 2019;39:9-29. © 2019 SETAC.


Assuntos
Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/metabolismo , Exposição Materna/efeitos adversos , Óvulo/metabolismo , Praguicidas/metabolismo , Tartarugas/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Região do Caribe , Feminino , Golfo do México , Bifenilos Policlorados/metabolismo
9.
Mar Environ Res ; 135: 43-54, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29395262

RESUMO

Knowledge of spatial variation in pollutant profiles among sea turtle nesting locations is limited. This poses challenges in identifying processes shaping this variability and sets constraints to the conservation management of sea turtles and their use as biomonitoring tools for environmental pollutants. We aimed to increase understanding of the spatial variation in polycyclic aromatic hydrocarbon (PAH), organochlorine pesticide (OCP) and polychlorinated biphenyl (PCB) compounds among nesting beaches. We link the spatial variation to turtle migration patterns and the persistence of these pollutants. Specifically, using gas chromatography, we confirmed maternal transfer of a large number of compounds (n = 68 out of 69) among 104 eggs collected from 21 nests across three nesting beaches within the Yucatán Peninsula, one of the world's most important rookeries for hawksbill turtles (Eretmochelys imbricata). High variation in PAH profiles was observed among beaches, using multivariate correspondence analysis and univariate Peto-Prentice tests, reflecting local acquisition during recent migration movements. Diagnostic PAH ratios reflected petrogenic origins in Celestún, the beach closest to petroleum industries in the Gulf of Mexico. By contrast, pollution profiles of OCPs and PCBs showed high similarity among beaches, reflecting the long-term accumulation of these pollutants at regional scales. Therefore, spatial planning of protected areas and the use of turtle eggs in biomonitoring needs to account for the spatial variation in pollution profiles among nesting beaches.


Assuntos
Gema de Ovo/química , Monitoramento Ambiental , Tartarugas , Poluentes Químicos da Água/análise , Animais , Golfo do México , Bifenilos Policlorados/análise
11.
Mar Pollut Bull ; 113(1-2): 7-16, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27726938

RESUMO

Micro- and macroplastic accumulation threatens estuaries worldwide because of the often dense human populations, diverse plastic inputs and high potential for plastic degradation and storage in these ecosystems. Nonetheless, our understanding of plastic sources and sinks remains limited. We designed conceptual models of the local and estuary-wide transport of plastics. We identify processes affecting the position of plastics in the water column; processes related to the mixing of fresh and salt water; and processes resulting from the influences of wind, topography, and organism-plastic interactions. The models identify gaps in the spatial context of plastic-organisms interactions, the chemical behavior of plastics in estuaries, effects of wind on plastic suspension-deposition cycles, and the relative importance of processes affecting the position in the water column. When interpreted in the context of current understanding, sinks with high management potential can be identified. However, source-sink patterns vary among estuary types and with local scale processes.


Assuntos
Monitoramento Ambiental , Estuários , Modelos Teóricos , Plásticos/análise , Resíduos/análise , Poluentes Químicos da Água/análise , Ecossistema , Resíduos/estatística & dados numéricos , Vento
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