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- Laranjeiro, F., et al.
(författare)
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Comparative assessment of the acute toxicity of commercial bio-based polymer leachates on marine plankton
- 2024
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 946
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Tidskriftsartikel (refereegranskat)abstract
- Conventional plastics have become a major environmental concern due to their persistence and accumulation in marine ecosystems. The development of potential degradable polymers (PBP), such as polyhydroxyalkanoates (PHAs) and polylactic acid (PLA), has gained attention as an alternative to mitigate plastic pollution, since they have the potential to biodegrade under certain conditions, and their production is increasing as replacement of conventional polyolefins. This study aimed to assess and compare the toxicity of leachates of pre-compounding PBP (PLA and the PHA, polyhydroxybutyrate-covalerate (PHBv)) and polypropylene (PP) on five marine planktonic species. A battery of standard bioassays using bacteria, microalgae, sea urchin embryos, mussel embryos and copepod nauplii was conducted to assess the toxicity of leachates from those polymers. Additionally, the presence of chemical additives in the leachates was also verified through GC-MS and LC-HRMS analysis. Results showed that PHBv leachates exhibited higher toxicity compared to other polymers, with the microalgae Rhodomonas salina, being the most sensitive species to the tested leachates. On the other hand, PP and PLA generally displayed minimal to no toxicity in the studied species. Estimated species sensitivity distribution curves (SSD) show that PHBv leachates can be 10 times more hazardous to marine plankton than PP or PLA leachates, as demonstrated by the calculated Hazardous Concentration for 5 % of species (HC5). Qualitative chemical analysis supports the toxicological results, with 80 % of compounds being identified in PHBv leachates of which 2,4,6-trichlorophenol is worth mentioning due to the deleterious effects to aquatic biota described in literature. These findings underscore the fact that whereas environmental persistence can be targeted using PBP, the issue of chemical safety remains unsolved by some alternatives, such as PHBv. Gaining a comprehensive understanding of the toxicity profiles of PBP materials through a priori toxicological risk assessment is vital for their responsible application as alternatives to conventional plastics.
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- Beiras, R., et al.
(författare)
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Ingestion and contact with polyethylene microplastics does not cause acute toxicity on marine zooplankton
- 2018
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 360, s. 452-460
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Tidskriftsartikel (refereegranskat)abstract
- Toxicity of polyethylene microplastics (PE-MP) of size ranges similar to their natural food to zooplanktonic organisms representative of the main taxa present in marine plankton, including rotifers, copepods, bivalves, echinoderms and fish, was evaluated. Early life stages (ELS) were prioritized as testing models in order to maximize sensitivity. Treatments included particles spiked with benzophenone-3 (BP-3), a hydrophobic organic chemical used in cosmetics with direct input in coastal areas. Despite documented ingestion of both virgin and BP-3 spiked microplastics no acute toxicity was found at loads orders of magnitude above environmentally relevant concentrations on any of the invertebrate models. In fish tests some effects, including premature or reduced hatching, were observed after 12 d exposure at 10 mg L-1 of BP-3 spiked PE-MP. The results obtained do not support environmentally relevant risk of microplastics on marine zooplankton. Similar approaches testing more hydrophobic chemicals with higher acute toxicity are needed before these conclusions could be extended to other organic pollutants common in marine ecosystems. Therefore, the replacement of these polymers in consumer products must be carefully considered.
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- Bellas, Juan, et al.
(författare)
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A standardisation of Ciona intestinalis (Chordata, Ascidiacea) embryo-larval bioassay for ecotoxicological studies
- 2003
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Ingår i: Water Research. - 0043-1354. ; 37:19, s. 4613-4622
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Tidskriftsartikel (refereegranskat)abstract
- A standardisation of the ascidian Ciona intestinalis embryo-larval bioassay for marine pollution assessment has been developed. The minimum percentage of embryogenesis success was established to assess the quality of the biological material used; minimum sample size and number of replicates per treatment were also estimated. The suitability of artificial and natural seawater for the incubation of ascidian embryos and larvae was compared, and the optimum conditions of temperature, salinity, pH, density of embryos in the vials and the sperm/egg ratio were investigated. On the basis of the 10th percentile of the distribution of larval abnormalities, we proposed a threshold of 50% normal larvae in the control in order to consider the test of acceptable biological quality. According to our results n = 5 is a sufficiently high replication to detect 5% differences among treatment means with a power of P = 90% and alpha = 0.05, and a sampling size greater than or equal to222 allows a 95% confidence in the estimate with an error of 0.05. Egg density did not affect larval development within the range 1-20 eggs/ml, and the optimum sperm/egg ratio which fertilise 100% of the eggs was 3000-30,000 sperm/egg (i.e. 10(8)-10(7) sperm/ml). There were not significant differences between the two water types tested, and the optimum tolerance ranges were 18-23 degreesC temperature, 34-42 ppt salinity (42 ppt was the highest salinity tested), and 7.4-8.8 pH. The median effective concentration (EC50) of copper (Cu) causing a 50% reduction of normal hatched larvae was 54.2 mug/l (0.85 muM), which shows a sensitivity of this species similar to the commonly used bivalve and sea-urchin tests. The ascidian embryo-larval bioassay is an accurate, reliable, simple and rapid method that can be used in ecotoxicological studies. (C) 2003 Elsevier Ltd. All rights reserved.
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- Bellas, Juan, et al.
(författare)
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Embryotoxicity of the antifouling biocide zinc pyrithione to sea urchin (Paracentrotus lividus) and mussel (Mytilus edulis)
- 2005
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X. ; 50:11, s. 1382-1385
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Tidskriftsartikel (refereegranskat)abstract
- The effects of the new antifouling compound zinc pyrithione (Zpt) on the embryonic development of sea urchin (Paracentrotus lividus) and mussel (Mytilus edulis) were investigated in laboratory toxicity tests. The median effective concentrations (EC50) were 7.7 nM for sea urchin embryos and 8 nM for mussel embryos. Toxic effects of Zpt on the larval growth of the sea urchin were detected at 0.5 nM. Predicted environmental concentrations of Zpt in pleasure craft harbours. are higher than the predicted no effect concentrations for sea urchin and mussel embryos, indicating that Zpt may pose a threat to those species from exposure in the field. (c) 2005 Elsevier Ltd. All rights reserved.
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- Eifert, S, et al.
(författare)
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Applying the Gender Lens to Risk Factors and Outcome after Adult Cardiac Surgery
- 2014
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Ingår i: Viszeralmedizin. - : S. Karger AG. - 1662-6664. ; 30:2, s. 99-106
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Tidskriftsartikel (refereegranskat)abstract
- <b><i>Background: </i></b>Applying the gender lens to risk factors and outcome after adult cardiac surgery is of major clinical interest, as the inclusion of sex and gender in research design and analysis may guarantee more comprehensive cardiovascular science and may consecutively result in a more effective surgical treatment as well as cost savings in cardiac surgery. <b><i>Methods: </i></b>We have reviewed classical cardiovascular risk factors (diabetes, arterial hypertension, hyperlipidemia, smoking) according to a gender-based approach. Furthermore, we have examined comorbidities such as depression, renal insufficiency, and hormonal influences in regard to gender. Gender-sensitive economic aspects have been evaluated, surgical outcome has been analyzed, and cardiovascular research has been considered from a gender perspective. <b><i>Results: </i></b>The influence of typical risk factors and outcome after cardiac surgery has been evaluated from a gender perspective, and the gender-specific distribution of these risk factors is reported on. The named comorbidities are listed. Economic aspects demonstrated a gender gap. Outcome after coronary and valvular surgeries as well as after heart transplantation are displayed in this regard. Results after postoperative use of intra-aortic balloon pump are shown. Gender-related aspects of clinical and biomedical cardiosurgical research are reported. <b><i>Conclusions: </i></b>Female gender has become an independent risk factor of survival after the majority of cardiosurgical procedures. Severely impaired left ventricular ejection fraction independently predicts survival in men, whereas age does in females.
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- Le Bihanic, F., et al.
(författare)
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Organic contaminants sorbed to microplastics affect marine medaka fish early life stages development
- 2020
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Ingår i: Marine Pollution Bulletin. - : Elsevier. - 0025-326X .- 1879-3363. ; 154
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Tidskriftsartikel (refereegranskat)abstract
- The role of polyethylene microplastics 4–6 μm size (MPs) in the toxicity of environmental compounds to fish early life stages (ELS) was investigated. Marine medaka Oryzias melastigma embryos and larvae were exposed to suspended MPs spiked with three model contaminants: benzo(a)pyrene (MP-BaP), perfluorooctanesulfonic acid (MP-PFOS) and benzophenone-3 (MP-BP3) for 12 days. There was no evidence of MPs ingestion but MPs agglomerated on the surface of the chorion. Fish ELS exposed to virgin MPs did not show toxic effects. Exposure to MP-PFOS decreased embryonic survival and prevented hatching. Larvae exposed to MP-BaP or MP-BP3 exhibited reduced growth, increased developmental anomalies and abnormal behavior. Compared to equivalent waterborne concentrations, BaP and PFOS appeared to be more embryotoxic when spiked on MPs than when alone in seawater. These results suggest a relevant pollutant transfer by direct contact of MPs to fish ELS that should be included in the ecotoxicological risk assessment of MPs.
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