To protect the integrity of sport, and the health of athletes, global anti-doping programmes seek to prevent doping, and elicit anti-doping and clean sport behaviours, through education, deterrence, detection, enforcement, and rules. To guide programme development, this meta-synthesis of qualitative research applied a behavioural science framework to identify barriers and enablers to doping, anti-doping, and clean sport. A systematic search of electronic databases up to May 2022, followed by critical appraisal, resulted in 73 included articles.
View Article and Find Full Text PDFFront Sports Act Living
December 2023
Background: Although athletes seem to hold uniform views towards non-dopers, their perception of dopers is more nuanced, reflecting positive and negative attributes. Research also indicates that rarely a single factor can explain doping, but a host of reasons that intertwine. A holistic understanding of how values play a role in decisions in anti-doping and the elements that influence athletes' doping vulnerability is timely and warranted.
View Article and Find Full Text PDFAnthropogenic releases of mercury (Hg) are a human health issue because the potent toxicant methylmercury (MeHg), formed primarily by microbial methylation of inorganic Hg in aquatic ecosystems, bioaccumulates to high concentrations in fish consumed by humans. Predicting the efficacy of Hg pollution controls on fish MeHg concentrations is complex because many factors influence the production and bioaccumulation of MeHg. Here we conducted a 15-year whole-ecosystem, single-factor experiment to determine the magnitude and timing of reductions in fish MeHg concentrations following reductions in Hg additions to a boreal lake and its watershed.
View Article and Find Full Text PDFFood webs in urban estuaries support valuable ecosystem services that are subject to a wide range of stressors that can degrade the structure of trophic networks. Multiple trophic pathways stabilize food webs by providing complementary diet resources for consumers but the consequences of urbanization on estuarine food webs are relatively unknown. In estuarine creeks across an urban-to-suburban gradient, we demonstrate trophic decoupling of benthic and pelagic pathways, trophic niche contraction, and increasing human health risk arising with the same factors that are associated with ecological degradation.
View Article and Find Full Text PDFCoral reefs are impacted by a variety of anthropogenic stressors including inputs of chemical contaminants. Although data is currently limited, sunscreens containing ultraviolet (UV) filters have recently been suggested as an emerging class of chemical contaminants. To provide further data on the toxicity of the UV filter oxybenzone (benzophenone-3 or BP-3) to corals, we conducted three independent acute toxicity tests exposing the colonial stony coral Galaxea fascicularis to BP-3 (0.
View Article and Find Full Text PDFThere has been a rapid increase in public, political, and scientific interest regarding the impact of organic ultraviolet (UV) filters to coral reefs. Such filters are found in sunscreens and other consumer products and enter the aquatic environment via direct (i.e.
View Article and Find Full Text PDFTo better understand the transformation and photochemical fate of PAHs in aquatic environments, a custom-designed closed-circuit recirculation photodegradation system, combined with inline semi-continuous fluorescence and absorbance measurements, as well as modelling of excitation-emission (EEM) measurements with parallel factor analysis (PARAFAC), and GC-MS analysis, were combined to create a robust tool for holistically assessing the photodegradation of individual PAHs, their mixtures and photoproduct formation. Selected compounds included in the US EPA priority list, representing 2- to 6-ring compounds, were monitored individually and in mixtures, during 24 h photodegradation experiments. Experiments were conducted in solutions simulating ideal (ultrapure water) and environmentally relevant conditions (1.
View Article and Find Full Text PDFThe occurrence of UV-filters in the environment has raised concerns over potentially adverse impacts on corals. In this study, the concentrations of 13 UV-filters and 11 hormones were measured in surface seawater, sediment, and coral tissue from 19 sites in Oahu, Hawaii. At least eight UV-filters were detected in seawater, sediment, and coral tissue and total mass concentrations of all UV-filters were <750 ng L, <70 ng g dry weight (dw), and <995 ng g dw, respectively.
View Article and Find Full Text PDFA correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
View Article and Find Full Text PDFSulfate reduction plays an important role in altering dissolved organic matter (DOM) in estuarine and coastal sediments, although its role in the production of optically active chromophoric DOM (CDOM) and a subset of fluorescent DOM (FDOM) has not been previously investigated in detail. Freshwater sediment slurries were incubated anaerobically with added sulfate and acetate to promote sulfate-reducing bacteria. Ultraviolet visible (UV-Vis) absorbance and 3-dimensional excitation emission matrix (EEM) fluorescence spectra were measured over a five weeks anaerobic dark incubation period.
View Article and Find Full Text PDFSimultaneous point measurements of gas velocity and temperature were recently demonstrated using thermographic phosphors as tracer particles. There, continuous wave (CW) excitation was used and the spectral shift of the luminescence was detected with a two-colour intensity ratio method to determine the gas temperature. The conventional laser Doppler velocimetry (LDV) technique was employed for velocimetry.
View Article and Find Full Text PDFLarval gray tree frogs (Hyla chrysoscelis) were exposed to inorganic Se (SeO) added to the diet (10.2 and 86.3 ug/g dw) and monitored for accumulation and effect.
View Article and Find Full Text PDFWe propose a point measurement technique for simultaneous gas temperature and velocity measurement based on thermographic phosphor particles dispersed in the fluid. The flow velocity is determined from the frequency of light scattered by BaMgAl10O17:Eu2+ phosphor particles traversing the fringes like in conventional laser Doppler velocimetry. Flow temperatures are derived using a two-color ratio method applied to the phosphorescence from the same particles.
View Article and Find Full Text PDFAn extensively diverse array of brominated disinfection byproducts (DBPs) were generated following electrochemical disinfection of natural coastal/estuarine water, which is one of the main treatment methods currently under consideration for ballast water treatment. Ultra-high-resolution mass spectrometry revealed 462 distinct brominated DBPs at a relative abundance in the mass spectra of more than 1%. A brominated DBP with a relative abundance of almost 22% was identified as 2,2,4-tribromo-5-hydroxy-4-cyclopentene-1,3-dione, which is an analogue to several previously described 2,2,4-trihalo-5-hydroxy-4-cyclopentene-1,3-diones in drinking water.
View Article and Find Full Text PDFThe concentration of 51 parent and alkylated PAHs was examined in oysters, Ostrea equestris, and corals, Tubastrea coccinea, collected from oil-rig structures off the coast of Louisiana during April and May 2011 to investigate their potential use as monitors for offshore contamination events. Corals and oysters collected from both sampling trips had lower PAH accumulation than most bivalves collected in previous studies near the shoreline of Louisiana and elsewhere in the Gulf of Mexico. In April, total PAH (TPAH) concentrations ranged from 8.
View Article and Find Full Text PDFMaternal transfer of methylmercury (MeHg) to eggs is an important exposure pathway for developing offspring. However, our understanding of this process is limited, particularly in estuarine fish. We conducted a 91-day chronic laboratory exposure of Cyprinodon variegatus to four concentrations of dietary MeHg ranging from 0.
View Article and Find Full Text PDFThe fate of mercury (Hg) deposited on forested upland soils depends on a wide array of biogeochemical and hydrological processes occurring in the soil landscape. In this study, Hg in soil, soilwater, and streamwater were measured across a forested upland subcatchment of the METAALICUS watershed in northwestern Ontario, Canada, where a stable Hg isotope (spike Hg) was applied to distinguish newly deposited Hg from Hg already resident in the watershed (ambient Hg). In total, we were able to account for 45% of the total mass of spike Hg applied to the subcatchment during the entire loading phase of the experiment, with approximately 22% of the total mass applied now residing in the top 15 cm of the mineral soil layer.
View Article and Find Full Text PDFWe performed an experiment in which larval gray tree frogs (Hyla chrysoscelis) were raised through metamorphosis on diets increased with a suite of elements associated with coal combustion residues (silver [Ag], arsenic [As], cadmium [Cd], chromium [Cr], copper [Cu], mercury [Hg], lead [Pb], selenium [Se], vanadium [V], and zinc [Zn]) at "low" and "high" concentrations. We quantified accumulation of metals at three life stages (mid-larval development, initiation of metamorphosis, and completion of metamorphosis) as well as effects on survival, metabolic rate, size at metamorphosis, and duration and loss of weight during metamorphosis. Most elements were accumulated in a dose-dependent pattern by some or all life stages, although this was not the case for Hg.
View Article and Find Full Text PDFDietary methylmercury (MeHg) uptake by fish in relation to life stage, species, and level of exposure is poorly understood in lower trophic levels, particularly in estuarine species. The authors compared accumulation of dietary MeHg as well as sensitivity (survival and growth) to dietary MeHg exposure in two species of estuarine forage fish, Cyprinodon variegatus and Menidia beryllina. Fish were fed one of five dietary MeHg concentrations (ranging from 0.
View Article and Find Full Text PDFSelenium (Se) is an essential micronutrient with a narrow therapeutic concentration range. The relative toxicity of Se increases as it is biotransformed into organic compounds, primarily selenomethionine (SeMet), within the aquatic food chain. Effects of aquatic Se contamination are well quantified for many freshwater fish and aquatic bird species, but impacts on amphibians are not well known.
View Article and Find Full Text PDFThis paper presents an optical diagnostic technique based on seeded thermographic phosphor particles, which allows the simultaneous two-dimensional measurement of gas temperature, velocity and mixture fraction in turbulent flows. The particle Mie scattering signal is recorded to determine the velocity using a conventional PIV approach and the phosphorescence emission is detected to determine the tracer temperature using a two-color method. Theoretical models presented in this work show that the temperature of small tracer particles matches the gas temperature.
View Article and Find Full Text PDFSelenium (Se) and vanadium (V) are contaminants commonly found in aquatic systems affected by wastes derived from fossil fuels. To examine their effects on a widely distributed species of amphibian, we exposed gray tree frogs (Hyla versicolor) to Se (as SeO₂) or V (as NaVO₃) in their diet from the early larval period to metamorphosis. Concentrations of Se in Se-enriched food were 1.
View Article and Find Full Text PDFMethylmercury (MeHg) bioaccumulation in marine food webs poses risks to fish-consuming populations and wildlife. Here we develop and test an estuarine mercury cycling model for a coastal embayment of the Bay of Fundy, Canada. Mass budget calculations reveal that MeHg fluxes into sediments from settling solids exceed losses from sediment-to-water diffusion and resuspension.
View Article and Find Full Text PDFVanadium (V) exerts a variety of effects related to metabolic function in vertebrates, including modifying glycolytic pathways and lipid metabolism. However, little is known about toxicity of V to wildlife in natural systems. We conducted parallel, independent studies to evaluate the effect of dietary exposure to vanadium on survival, metabolism, growth, and lipid storage of larval leopard frogs (Rana sphenocephala).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2007
Methylmercury contamination of fisheries from centuries of industrial atmospheric emissions negatively impacts humans and wildlife worldwide. The response of fish methylmercury concentrations to changes in mercury deposition has been difficult to establish because sediments/soils contain large pools of historical contamination, and many factors in addition to deposition affect fish mercury. To test directly the response of fish contamination to changing mercury deposition, we conducted a whole-ecosystem experiment, increasing the mercury load to a lake and its watershed by the addition of enriched stable mercury isotopes.
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