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1.
J Invertebr Pathol ; : 107555, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33607127

RESUMO

Harmful Algal Blooms (HAB) are natural atypical proliferations of micro or macro algae in either marine or freshwater environments which have significant impacts on human, animal and ecosystem health. The causative HAB organisms are primarily dinoflagellates and diatoms in marine and cyanobacteria within freshwater ecosystems. Several hundred species of HABs, most commonly marine dinoflagellates affect animal and ecosystem health either directly through physical, chemical or biological impacts on surrounding organisms or indirectly through production of algal toxins which transfer through lower-level trophic organisms to higher level predators. Traditionally, a major focus of HABs has concerned their natural production of toxins which bioaccumulate in filter-feeding invertebrates, which with subsequent trophic transfer and biomagnification cause issues throughout the food web, including the human health of seafood consumers. Whilst in many regions of the world, regulations, monitoring and risk management strategies help mitigate against the impacts from HAB/invertebrate toxins upon human health, there is ever-expanding evidence describing enormous impacts upon invertebrate health, as well as the health of higher trophic level organisms and marine ecosystems. This paper provides an overview of HABs and their relationships with aquatic invertebrates, together with a review of their combined impacts on animal, human and ecosystem health. With HAB/invertebrate outbreaks expected in some regions at higher frequency and intensity in the coming decades, we discuss the needs for new science, multi-disciplinary assessment and communication which will be essential for ensuring a continued increasing supply of aquaculture foodstuffs for further generations.

2.
Sci Total Environ ; 774: 145405, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33607436

RESUMO

Because of their unique properties, rare earth elements (REEs), comprising the lanthanide elements plus Sc and Y, have a variety of integral applications in modern electronic equipment. Consequently, it has been suggested that REEs may act as contaminants of and tracers for recycled electrical and electronic plastics in consumer goods. In this study, REEs have been determined in a range of consumer plastics of different polymeric makeup (n = 31), and purchased new and in societal circulation, by inductively coupled plasma-mass spectrometry following acid digestion. Samples were also screened by X-ray fluorescence spectrometry for Br and Sb as markers of brominated flame retardants and the retardant synergist, Sb2O3, respectively. One or more REE was detected in 24 samples, with four samples returning detectable concentrations of all REEs analysed and with total REE concentrations up to 8 mg kg-1. REEs were most commonly observed in samples containing Br and Sb at levels insufficient to effect flame retardancy and, therefore, likely derived from recycled electronic plastic, but were not detectable in new electrical plastics. Various REEs were also present in plastics with no detectable Br and Sb, however, and where unregulated recycling is prohibited (e.g. food packaging). This observation, and correlations between pairs of REEs for all samples considered, suggests a more generic source of these elements in consumer plastics in addition to the recycling of electrical and electronic waste. REEs reported in the literature for beached marine plastics were characterised by similar concentrations and inter-element correlations, suggesting that REEs are ubiquitous and pervasive contaminants of both contemporary and historical consumer and environmental plastics.

3.
Mar Drugs ; 19(2)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540777

RESUMO

A potent and heat-stable tetrodotoxin (TTX) has been found to accumulate in various marine bivalve species, including Pacific oysters (Crassostrea gigas), raising a food safety concern. While several studies on geographical occurrence of TTX have been conducted, there is a lack of knowledge about the distribution of the toxin within and between bivalves. We, therefore, measured TTX in the whole flesh, mantle, gills, labial palps, digestive gland, adductor muscle and intravalvular fluid of C. gigas using liquid chromatography-tandem mass spectrometry. Weekly monitoring during summer months revealed the highest TTX concentrations in the digestive gland (up to 242 µg/kg), significantly higher than in other oyster tissues. Intra-population variability of TTX, measured in the whole flesh of each of twenty animals, reached 46% and 32% in the two separate batches, respectively. In addition, an inter-population study was conducted to compare TTX levels at four locations within the oyster production area. TTX concentrations in the whole flesh varied significantly between some of these locations, which was unexplained by the differences in weight of flesh. This is the first study examining TTX distribution in C. gigas and the first confirmation of the preferential accumulation of TTX in oyster digestive gland.

4.
Mar Drugs ; 19(2)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572171

RESUMO

Most of the shellfish fisheries of Mexico occur in the Gulf of California. In this region, known for its high primary productivity, blooms of diatoms and dinoflagellates are common, occurring mainly during upwelling events. Dinoflagellates that produce lipophilic toxins are present, where some outbreaks related to okadaic acid and dinophisystoxins have been recorded. From January 2015 to November 2017 samples of three species of wild bivalve mollusks were collected monthly in five sites in the southern region of Bahía de La Paz. Pooled tissue extracts were analyzed using LC-MS/MS to detect lipophilic toxins. Eighteen analogs of seven toxin groups, including cyclic imines were identified, fortunately individual toxins did not exceed regulatory levels and also the total toxin concentration for each bivalve species was lower than the maximum permitted level for human consumption. Interspecific differences in toxin number and concentration were observed in three species of bivalves even when the samples were collected at the same site. Okadaic acid was detected in low concentrations, while yessotoxins and gymnodimines had the highest concentrations in bivalve tissues. Although in low quantities, the presence of cyclic imines and other lipophilic toxins in bivalves from the southern Gulf of California was constant.

5.
Br J Gen Pract ; 2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33558332

RESUMO

BACKGROUND: To reduce contagion of COVID-19, in March 2020 UK general practices implemented predominantly remote consulting via telephone, video, or online consultation platforms. AIM: To investigate the rapid implementation of remote consulting and explore impact over the initial months of the COVID-19 pandemic. DESIGN AND SETTING: Mixed-methods study in 21 general practices in Bristol, North Somerset and South Gloucestershire. METHOD: Longitudinal observational quantitative analysis compared volume and type of consultation in April to July 2020 with April to July 2019. Negative binomial models were used to identify if changes differed among different groups of patients. Qualitative data from 87 longitudinal interviews with practice staff in four rounds investigated practices' experience of the move to remote consulting, challenges faced, and solutions. A thematic analysis utilised Normalisation Process Theory. RESULTS: There was universal consensus that remote consulting was necessary. This drove a rapid change to 90% remote GP consulting (46% for nurses) by April 2020. Consultation rates reduced in April to July 2020 compared to 2019; GPs and nurses maintained a focus on older patients, shielding patients, and patients with poor mental health. Telephone consulting was sufficient for many patient problems, video consulting was used more rarely, and was less essential as lockdown eased. SMS-messaging increased more than three-fold. GPs were concerned about increased clinical risk and some had difficulties setting thresholds for seeing patients face-to-face as lockdown eased. CONCLUSION: The shift to remote consulting was successful and a focus maintained on vulnerable patients. It was driven by the imperative to reduce contagion and may have risks; post-pandemic, the model will need adjustment.

6.
Environ Pollut ; 271: 116400, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33421845

RESUMO

Freshwater cyanobacteria produce highly toxic secondary metabolites, which can be transported downstream by rivers and waterways into the sea. Estuarine and coastal aquaculture sites exposed to toxic cyanobacteria raise concerns that shellfish may accumulate and transfer cyanotoxins in the food web. This study aims to describe the competitive pattern of uptake and depuration of a wide range of microcystins (MC-LR, MC-LF, MC-LW, MC-LY, [Asp3]-MC-LR/[Dha7]-MC-LR, MC-HilR) and nodularins (NOD cyclic and linear) within the common blue mussel Mytilus edulis exposed to a combined culture of Microcystis aeruginosa and Nodularia spumigena into the coastal environment. Different distribution profiles of MCs/NODs in the experimental system were observed. The majority of MCs/NODs were present intracellularly which is representative of healthy cyanobacterial cultures, with MC-LR and NOD the most abundant analogues. Higher removal rate was observed for NOD (≈96%) compared to MCs (≈50%) from the water phase. Accumulation of toxins in M. edulis was fast, reaching up to 3.4 µg/g shellfish tissue four days after the end of the 3-days exposure period, with NOD (1.72 µg/g) and MC-LR (0.74 µg/g) as the dominant toxins, followed by MC-LF (0.35 µg/g) and MC-LW (0.31 µg/g). Following the end of the exposure period depuration was incomplete after 27 days (0.49 µg/g of MCs/NODs). MCs/NODs were also present in faecal material and extrapallial fluid after 24 h of exposure with MCs the main contributors to the total cyanotoxin load in faecal material and NOD in the extrapallial fluid. Maximum concentration of MCs/NODs accumulated in a typical portion of mussels (20 mussels, ≈4 g each) was beyond greater the acute, seasonal and lifetime tolerable daily intake. Even after 27 days of depuration, consuming mussels harvested during even short term harmful algae blooms in close proximity to shellfish beds might carry a high health risk, highlighting the need for testing.


Assuntos
Cianobactérias , Microcystis , Animais , Microcistinas , Nodularia , Frutos do Mar/análise
7.
Chemosphere ; 263: 128087, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297085

RESUMO

Polystyrene foam (expanded and extruded polystyrene: EPS and XPS, respectively) is a ubiquitous and pervasive type of marine plastic whose physical properties, transport and fate are distinctly different to those of other common (unfoamed) types of thermoplastic litter. In this study, a range of fragments of EPS and XPS retrieved from three beaches in southwest England have been characterised by energy-dispersive X-ray fluorescence (XRF) spectrometry in order to examine the chemical makeup and potential biological and geochemical impacts and interactions of this type of plastic waste. Analyses performed through sample faces and, in some cases and after dissection, through the material core, revealed variable concentrations of Fe, Ti and Zn among the fragments and, in many instances, within the same sample. This likely reflects the presence of reaction residues and pigments arising from the manufacture of polystyrene, and, for Fe and Ti, significant and heterogeneous ion and mineral acquisition from the environment during transport in suspension or while beached. Acquired oxides of Fe are partly responsible for the chemical fouling observed on the face of most samples and are able to act as an adsorbent for other metals, like Pb. Detection of Br in many fragments up to concentrations of 11,500 mg kg-1 likely results from the incorporation of the flame retardant, hexabromocyclododecane, in EPS and XPS designed for (but not necessarily limited to) the construction sector. These observations suggest that EPS and XPS can act as both a source and sink for contaminants in the marine environment that merit further investigation.


Assuntos
Retardadores de Chama , Poliestirenos , Inglaterra , Monitoramento Ambiental , Retardadores de Chama/análise , Plásticos , Poliestirenos/análise
8.
J Hazard Mater ; 404(Pt A): 124131, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049630

RESUMO

X-ray fluorescence spectrometry has been employed to measure Pb in a wide range of consumer and environmental plastics, including food-packaging material, household goods, electronic casings, beach litter and agricultural waste. Results reveal high concentrations of Pb (>1000 mg kg-1) in historical items that are still in use or circulation (e.g. toys, construction plastics, wiring insulation) and variable, but generally lower concentrations in more recently manufactured articles. Analysis of Br, Cl and Cr, proxies for brominated flame retardants, polyvinyl chloride (PVC) and chromate pigments, respectively, suggests that as historical material is recycled, Pb from electronic plastics and pigments, but not PVC, is dispersed into a variety of newer products. Although most cases in the consumer sector comply with relevant EU Directives, some products that are non-compliant highlight shortfalls in regulations where recycling is involved and potential problems arising from the direct fashioning of industrial plastics into new consumer goods through attempts to be environmentally positive. The uncontrolled loss of historical and recycled plastics has also resulted in Pb contamination of the environment. Here, it is proposed that litter can be classified as hazardous depending on its Pb content and according to existing regulations that embrace consumer plastics.

9.
Chemosphere ; 262: 128290, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182139

RESUMO

Tumble dryer lint has been employed as a surrogate for synthetic and processed (microplastic) fibres discharged to the environment from laundering activities and exposed to marine mussels (Mytilus galloprovinciallis) in controlled experiments for a period of 7 d. A range of biological responses at different levels of organisation were subsequently determined, with copper employed concurrently as a positive control. Physiological changes were assessed from measurements of clearance rate, histopathological effects were evaluated from abnormalities in (or injuries to) gill and digestive gland tissues, and genetic damage was determined by measuring DNA strand breaks using the comet assay. With increasing lint concentration (over the range 56-180 mg L-1) we observed a reduction in mean clearance rate, increasing extents of abnormality in both gills (e.g. deciliation and hypertrophy) and digestive gland (e.g. atrophy and necrosis), and an increase in damage to DNA. The precise causes of these effects are unclear but likely arise from both the fibrous material itself and from chemicals (e.g. additives and metals) that are mobilised from the polymers into seawater or the digestive tract. The latter assertion is consistent with an observed increase in the release of certain trace elements (e.g. zinc) into the exposure medium with increasing lint concentration. Although microfibre concentrations we employed are significantly greater than those typically encountered in the environment, the results indicate the potential for this type of material to exert a range of adverse effects on exposed marine animals.


Assuntos
Dano ao DNA , Microplásticos/toxicidade , Mytilus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Ensaio Cometa , Cobre/toxicidade , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Taxa de Depuração Metabólica , Modelos Teóricos , Mytilus/genética , Mytilus/metabolismo , Água do Mar/química
10.
J Hazard Mater ; 403: 123799, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264903

RESUMO

Exposure of microplastics (MPs) to a cohort of adults of various demographics from different regions of Iran has been quantitatively assessed. Specifically, MPs were retrieved from filtered washes of the hand and face skin, head hair and saliva of individuals (n = 2000) after an exposure period of 24 h and were counted and, in a selected number of cases, characterised for shape-form and size microscopically. A total of over 16,000 MPs were recorded in the study, with head hair returning the most samples (> 7000, or, on average, >3.5 MPs per individual per day), saliva returning the least samples (about 650, or on average 0.33 MPs per individual), and MPs about twice as high in males than females. The number of MPs was similar amongst residents of different urbanised regions, albeit with evidence of greater quantities captured in more humid settings, and was considerably lower in residents of a remote and sparsely populated area. Polyethylene-polyethylene terephthalate and polypropylene fibres of < 100 µm in length, likely derived from clothing and soft furnishings in the indoor setting and a wider range of sources in the exterior environment, were the most abundant type of MP in all body receptors. Daily sampling of receptors from six participants over a seven-day period revealed that, despite these broad trends, both inter- and intra-individual exposure was highly heterogeneous. Although the present study has demonstrated the ubiquity of MP exposure, the resulting impacts on human health are unknown.

11.
Mar Drugs ; 18(12)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33287439

RESUMO

With the move away from use of mouse bioassay (MBA) to test bivalve mollusc shellfish for paralytic shellfish poisoning (PSP) toxins, countries around the world are having to adopt non-animal-based alternatives that fulfil ethical and legal requirements. Various assays have been developed which have been subjected to single-laboratory and multi-laboratory validation studies, gaining acceptance as official methods of analysis and approval for use in some countries as official control testing methods. The majority of validation studies conducted to date do not, however, incorporate shellfish species sourced from Latin America. Consequently, this study sought to investigate the performance of five alternative PSP testing methods together with the MBA, comparing the PSP toxin data generated both qualitatively and quantitatively. The methods included a receptor binding assay (RBA), two liquid chromatography with fluorescence detection (LC-FLD) methods including both pre-column and post-column oxidation, liquid chromatography with tandem mass spectrometry (LC-MS/MS) and a commercial lateral flow assay (LFA) from Scotia. A total of three hundred and forty-nine shellfish samples from Argentina, Mexico, Chile and Uruguay were assessed. For the majority of samples, qualitative results compared well between methods. Good statistical correlations were demonstrated between the majority of quantitative results, with a notably excellent correlation between the current EU reference method using pre-column oxidation LC-FLD and LC-MS/MS. The LFA showed great potential for qualitative determination of PSP toxins, although the findings of high numbers of false-positive results and two false negatives highlighted that some caution is still needed when interpreting results. This study demonstrated that effective replacement methods are available for countries that no longer wish to use the MBA, but highlighted the importance of comparing toxin data from the replacement method using local shellfish species of concern before implementing new methods in official control testing programs.

12.
Acc Chem Res ; 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258604

RESUMO

ConspectusThis Account presents recent advances in our understanding on the formation pathways of complex organic molecules (COMs) within interstellar analog ices on ice-coated interstellar nanoparticles upon interaction with ionizing radiation exploiting reflectron time-of-flight mass spectrometry (ReTOF-MS) coupled with tunable vacuum ultraviolet (VUV) single photon ionization (PI) and resonance enhanced multiphoton ionization (REMPI) of the subliming molecules during the temperature-programmed desorption (TPD) phase. Laboratory simulation experiments provided compelling evidence that key classes of complex organics (aromatic hydrocarbons, alcohols, ethers, aldehydes, enols, ketones, and carboxylic acids) can be synthesized upon exposure of astrophysically relevant model ices to ionizing radiation within and throughout the ices at temperatures as low as 5 K.Molecular mass growth processes can be initiated by suprathermal or electronically excited reactants along with barrierless radical-radical recombination if both radicals hold a proper recombination geometry. Methyl (CH3), amino (NH2), hydroxyl (OH), ethyl (C2H5), vinyl (C2H3), ethynyl (C2H), formyl (HCO), hydroxycarbonyl (HOCO), hydroxymethyl (CH2OH), methoxy (CH3O), and acetyl (CH3CO) represent readily available reactants for radical-radical recombination within the ices. Reactive singlet species were found to insert without barrier into carbon-hydrogen and carbon-carbon single bonds (carbene) leading to an extension of the carbon chain and may add to carbon-carbon double bonds (carbene, atomic oxygen) forming cyclic reaction products. These galactic cosmic ray-triggered nonequilibrium pathways overcome previous obstacles of hypothesized thermal grain-surface processes and operate throughout the ice at 5 K. Our investigations discriminate between multiple structural isomers such as alcohols/ethers, aldehydes/enols, and cyclic/acyclic carbonyls. These data provide quantitative, isomer selective input parameters for a cosmic ray-dictated formation of complex organics in interstellar ices and are fully able to replicate the astronomical observations of complex organics over typical lifetimes of molecular clouds of a few 106 to 107 years. Overall, PI-ReTOF-MS revealed that the processing of astrophysically relevant ices can lead to multifaceted mixtures of organics reaching molecular weights of up to 200 amu. Further advances in laboratory techniques beyond the FTIR-QMS limit are clearly desired not only to confidently assign detection in laboratory ice analog experiments of increasingly more complex molecules of interest but also from the viewpoint of future astronomical searches in the age of the Atacama Large Millimeter/submillimeter Array (ALMA).

13.
Chemistry ; 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33368689

RESUMO

The identification of silicon-substituted, complex organics carrying multiple functional groups by classical infrared spectroscopy is challenging because the group frequencies of functional groups often overlap. Photoionization (PI) reflectron time-of-fight mass spectrometry (ReTOF-MS) in combination with temperature-programmed desorption (TPD) holds certain advantages because molecules are identified after sublimation from the matrix into in the gas phase based on distinct ionization energies and sublimation temperatures. In this study, we reveal the detection of 1-silaglycolaldehyde (HSiOCH2 OH), 2-sila-acetic acid (H3 SiCOOH), and 1,2-disila-acetaldehyde (H3 SiSiHO)-the silicon analogues of the well-known glycolaldehyde (HCOCH2 OH), acetic acid (H3 CCOOH), and acetaldehyde (H3 CCHO), in the gas phase after preparation in silane (SiH4 )-carbon dioxide ices exposed to energetic electrons and subliming the neutral reaction products formed within the ices into the gas phase.

14.
Harmful Algae ; 99: 101910, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33218436

RESUMO

Paralytic Shellfish Poisoning is a potentially fatal syndrome, resulting from the filter-feeding activities of marine molluscs accumulating harmful neurotoxins naturally occurring in microalgae. Outbreaks are well recognised throughout most regions of the world, but with the highest levels of toxicity to date recorded in mussels from Argentina. Whilst toxicity has been documented for selected outbreaks over the years, testing has been conducted using a mouse bioassay. Consequently there is a need to establish baseline data utilising modern chemical detection methods, which also facilitate the quantification of individual toxin analogues, giving useful data on toxin profiles as well as total sample toxicity. In this study, 151 shellfish samples harvested from the marine waters of Argentina between 1980 and 2012 were subjected to analysis by liquid chromatography with fluorescence detection, since Jan 2019 the European Union reference method for PSP determination. Total PST concentrations were found to vary enormously throughout the coastline of Argentina, with higher levels of toxins found in the central regions of Rio Negro and Chubut. Toxin profiles in terms of molar percentage of total concentrations were dominated by the gonyautoxins GTX1&4 and GTX2&3, followed by C1&2, STX and dcGTX2&3, with minor levels of other analogues previously not reported in the country. Profiles were found to vary significantly, with statistical clusters of profile types associated with a wide range of factors, including species, spatial and temporal differences, as well as likely source microalgae species and potential toxin transformation pathways. Overall application of the chemical detection method has confirmed both the significant risk to shellfish consumers in Argentina with periodic outbreaks of extremely high toxin levels and a large variability in toxin profiles relating in part to previously reported variabilities in microalgal toxin content. The study has demonstrated the potential for the method to systematically study the relationships between toxicity, toxin profile, source phytoplankton and other environmental factors.

15.
Harmful Algae ; 98: 101890, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33129448

RESUMO

Blooms of harmful algae are increasing globally, yet their impacts on copepods, an important link between primary producers and higher trophic levels, remain largely unknown. Algal toxins may have direct, negative effects on the survival of copepods. They may also indirectly affect copepod survival by deterring feeding and thus decreasing the availability of energy and nutritional resources. Here we present a series of short-term (24 h) experiments in which the cosmopolitan marine copepod, Acartia tonsa, was exposed to a range of concentrations of the toxic dinoflagellate, Alexandrium catenella (strain 1119/27, formerly Alexandrium tamarense), with and without the presence of alternative, non-toxic prey (Rhodomonas sp.). We also present the toxin profile concentrations for A. catenella. The survival and feeding of A. tonsa were not affected across the range of concentrations recorded for A. catenella in the field; increased mortality of A. tonsa was only discernible when A. catenella was present at concentrations that exceed their reported environmental concentrations by two orders of magnitude. The observed lethal median concentration (LC50) for A. tonsa exposed to A. catenella was 12.45 ng STX eq L-1. We demonstrate that A. tonsa is capable of simultaneously ingesting both toxic and non-toxic algae, but increases clearance rates towards non-toxic prey as the proportional abundance of toxic A. catenella increases. The ability to actively select non-toxic algae whilst also ingesting toxic algae suggests that consumption of the latter does not cause physical incapacitation and thus does not affect ingestion in A. tonsa. This work shows that short-term exposure to toxic A. catenella is unlikely to elicit major effects on the grazing or survival of A. tonsa. However, more work is needed to understand the longer-term and sub-lethal effects of toxic algae on marine copepods.

17.
Regul Toxicol Pharmacol ; 119: 104824, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33221423

RESUMO

Polyester fibres are usually contaminated by antimony because of its use as a catalyst in the production of polyethylene terephthalate and as a flame retardant synergist in a variety of new and recycled polymers. The present study determined the release of antimony (at total concentrations ranging from about 125 to 470 µg g-1) from polyester textile samples designed to be in contact with human skin using standard artificial sweat solutions (ISO 105-E04 and EN 1811). The study also examined the role of different experimental parameters on the release of the metalloid. Overall, and using the default parameters, between about 0.05 and 2% of total antimony (or 0.1-1 µg g-1) was mobilized into artificial sweat. A reduction in time (from 24 to 12 h) and temperature (from 37 to 20 or 4 °C) and an increase in pH (from 5.5 to 7) resulted in a decline in antimony mobilization from textiles, while altering textile mass to solution volume and the presence of lactate had little impact on the results. Removal of a filtration step increased antimony mobilization but this was attributed to artefacts associated with release from microfibres during extract storage and analysis. In general, antimony mobilization was sufficiently repeatable using either EN 1811 or ISO 105-E04 but the latter is recommended for an assessment of antimony mobilization and potential exposure because its pH is closer to that of human sweat. Since the first fraction of either extractions mobilized the greatest quantity of antimony, exposure can be minimized by washing articles before use.

18.
JMIR Res Protoc ; 9(12): e24264, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33237877

RESUMO

BACKGROUND: During the COVID-19 lockdown period in the United Kingdom that began on March 23, 2020, more than a quarter of a million people with cancer reported worsening mental health. Help to Overcome Problems Effectively (Hope) is a self-management program for people with cancer, designed to provide support for distress, unmet needs, and poor psychological health. In light of social distancing during the COVID-19 pandemic, digital delivery of the Hope Programme has become ever more vital for people with cancer. Previous pre-post studies of the digital Hope Programme have found reduced anxiety and depression and improved well-being for people with cancer. However, evaluation of this evidence has been limited by the lack of a control group in these previous studies. OBJECTIVE: We now present a protocol for a feasibility randomized controlled trial of the digital Hope Programme for people with cancer during the COVID-19 pandemic. Primary outcomes will be recruitment, dropout, and adherence rates, and estimations of sample and effect size. To detect signals of efficacy, secondary outcomes will be participant mental health and well-being. METHODS: Participants will be recruited by Macmillan Cancer Support (MCS) through their social media networks. The study will employ a feasibility wait-list randomized controlled trial (RCT) design, with people with cancer being randomized to join the digital Hope Programme immediately (intervention group [IG]) or join a 6-week waiting list (wait-list control group [WLCG]) with a 1:1 allocation ratio. Participants will complete digital measures of depression, anxiety, mental well-being, and confidence in managing their own health. Online questionnaires will be administered preprogram and 6 weeks postprogram. RESULTS: All people who had requested access to the Hope Programme from MCS (N=61) will be invited to participate in the trial. Baseline data collection commenced in April 2020, and the Hope Programme began for the IG in May 2020 and for the WLCG in June 2020. Postprogram data collection was completed by the end of August 2020. CONCLUSIONS: This feasibility study will provide data to inform the design of a future definitive trial. Wider-scale provision of the digital Hope Programme has potential to improve the lives of thousands of people with cancer and reduce the burden on health care providers during these unprecedented times. TRIAL REGISTRATION: ISRCTN Registry ISRCTN79623250; http://www.isrctn.com/ISRCTN79623250. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/24264.

19.
Environ Pollut ; 268(Pt A): 115754, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33032097

RESUMO

Antifouling paint particles (APPs) and associated metals have been identified in sediments around boatyards and marinas globally, but the effects of APPs on benthic organisms are largely unknown. Sub-lethal endpoints were measured following laboratory exposures of the harbour ragworm (Hediste diversicolor) and the common cockle (Cerastoderma edule) to environmentally relevant concentrations of biocidal ('modern' and 'historic') and biocide-free ('silicone') APPs added to clean estuarine sediment. Further, the 5-day median lethal concentrations (LC50) and effects concentrations (EC50) for modern biocidal APPs were calculated. For ragworms, significant decreases in weight (15.7%; p < 0.01) and feeding rate (10.2%; p < 0.05) were observed in the modern biocidal treatment; burrowing behaviour was also reduced by 29% in this treatment, but was not significant. For cockles, the modern biocidal treatment led to 100% mortality of all replicates before endpoints were measured. In cockles, there was elevated levels of metallothionein-like protein (MTLP) in response to both modern and historic biocidal treatments. Ragworms had a higher tolerance to modern APPs (5-day LC50:19.9 APP g L-1; EC50: 14.6 g L-1) compared to cockles (5-day LC50: 2.3 g L-1 and EC50: 1.4 g L-1). The results of this study indicate that modern biocidal APPs, containing high Cu concentrations, have the potential to adversely affect the health of benthic organisms at environmentally relevant concentrations. The findings highlight the need for stricter regulations on the disposal of APP waste originating from boatyards, marinas and abandoned boats.

20.
Nat Commun ; 11(1): 5184, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056977

RESUMO

The global monsoon is characterised by transitions between pronounced dry and wet seasons, affecting food security for two-thirds of the world's population. Rising atmospheric CO2 influences the terrestrial hydrological cycle through climate-radiative and vegetation-physiological forcings. How these two forcings affect the seasonal intensity and characteristics of monsoonal precipitation and runoff is poorly understood. Here we use four Earth System Models to show that in a CO2-enriched climate, radiative forcing changes drive annual precipitation increases for most monsoon regions. Further, vegetation feedbacks substantially affect annual precipitation in North and South America and Australia monsoon regions. In the dry season, runoff increases over most monsoon regions, due to stomatal closure-driven evapotranspiration reductions and associated atmospheric circulation change. Our results imply that flood risks may amplify in the wet season. However, the lengthening of the monsoon rainfall season and reduced evapotranspiration will shorten the water resources scarcity period for most monsoon regions.


Assuntos
Dióxido de Carbono/metabolismo , Modelos Teóricos , Chuva , Recursos Hídricos , Vento , Atmosfera/química , Austrália , Ciclo do Carbono , Dióxido de Carbono/análise , Mudança Climática , Planeta Terra , Inundações , América do Norte , Estações do Ano , América do Sul , Temperatura , Ciclo Hidrológico
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