Ecotoxicological Investigation in Three Model Species Exposed to Elutriates of Marine Sediments Inoculated With Bioplastics

The aim of this study was to evaluate a set of ecotoxicity biotests on three marine model species exposed to elutriates of marine sediments inoculated with the biodegradable plastic Mater-Bi or with cellulose. The sediments were incubated at 28°C and tested after 6 months, when clear signs of degradation were visible in the exposed samples, and after 12 months, when the samples had completely disappeared. The model organisms selected for the study were the unicellular algae Dunaliella tertiolecta, the sea urchin (Paracentrotus lividus) and sea bass (Dicentrarchus labrax) juveniles. The unicellular algae and sea urchins were used to determine the toxicological endpoint of growth inhibition and embryotoxicity, respectively, and the sea bass juveniles were tested to evaluate sublethal effect endpoints using lipid peroxidation and genotoxicity biomarkers. Elutriates of sediment inoculated with Mater-Bi for 6 and 12 months showed an absence of toxic effects in all of the model organisms exposed in this study. The Mater-Bi degradation process did not generate or transfer into the elutriates toxic substances that could cause alterations in the growth of D. tertiolecta, in the P. lividus embryo-toxicity assay or in the sensitive biomarker responses of the fish D. labrax. The tested species are considered to be representatives of different levels of the marine trophic chain. The results obtained in this study suggest that the ecotoxicological approach applied may be suitable for investigating the environmental impact of the degradation of bioplastics in marine sediments

PDMS-based films containing surface-active amphiphilic block copolymers to combat fouling from barnacles B. amphitrite and B. improvisus

Surface-active amphiphilic diblock copolymers, Si-EFS14 and Si-EFS71, consisting of a poly(dimethyl siloxane) block (degree of polymerisation 11) and a poly(4-(triethyleneglycol monomethyl ether)-2,3,5,6-tetrafluorostyrene) block (average degree of polymerisation 14 and 71) were synthesised by ATRP. Films were prepared by incorporating each copolymer (4 wt%) into a PDMS matrix, which was then condensation cured. Bioassays were performed on the films using two barnacle species, Balanus amphitrite and Balanus improvisus, at different stages of their life cycles. The cyprids of B. improvisus settled on all test surfaces in higher numbers than those of B. amphitrite. However, the juveniles of B. improvisus were more easily removed from the films containing the copolymer Si-EFS14 than from those containing the copolymer Si-EFS71. An XPS analysis revealed that the near-surface region of copolymer Si-EFS71 was enriched in oxyethylenic chains and became even more populated by these hydrophilic chains after the films were immersed in water

Gill histopathology in zebrafish model following exposure to aquacultural disinfectants

The effect of acute exposure of four disinfectants commonly used in aquacultural practice (formalin, potassium permanganate, benzalkonium chloride and malachite green) was studied on the histological structure of adult zebrafish (Danio rerio) gills. Groups of 8 individuals were exposed to a dose of each disinfectant corresponding to the therapeutic dose (TD) and five folds of the therapeutic dose (5xTD). Gills of all exposed zebrafish showed a higher occurrence of histopathological changes. These alterations included a slightly focal proliferation of interlamellar cells with obliteration of interlamellar spaces, mild infiammatory reaction with leucocyte infiltration and lifting of the epithelial layer from gill lamellae. Fish exposed to potassium permanganate showed more severe histopathological changes consisting of necrotic change of lamellar cells, distorsion and apical necrosis of secondary lamellae

Arrecifes coralígenos infralitorales: estructura y variabilidad espacial de las comunidades de macroalgas

Coralligenous reefs are calcareous structures edified mostly by coralline algae that characterize the circalittoral zone of the Mediterranean Sea. However, in some cases coralline algae can constitute peculiar infralittoral biogenic reefs which have been studied less than the circalittoral ones. This study aims to contribute to the knowledge of infralittoral coralligenous reefs by describing their macroalgal assemblages on a large rocky platform off the Tuscany coasts, northwestern Mediterranean Sea. To this end, a multifactorial sampling design was used to describe the structure of the assemblages and to evaluate the variability of the system at multiple spatial scales. A total of 71 macroalgal taxa were found on the coralline algae. Macroalgal assemblages were well structured, with high biodiversity values. The dominant taxa included both photophilous and sciaphilous species, guaranteeing peculiar characteristics in these assemblages, above all if compared with the typical infralittoral and circalittoral macroalgal communities of the same geographic area. The assemblages showed greater variability at a small and intermediate spatial scale than at a large scale. Although infralittoral coralligenous outcrops constitute a peculiar system, they are still poorly understood and should not only be the object of specific studies but also be included in monitoring programmes.Los arrecifes coralígenos son estructuras calcáreas edificadas principalmente por algas coralinas que caracterizan la zona circalitoral del Mar Mediterráneo. Sin embargo, en algunos casos las algas coralinas pueden constituir peculiares arrecifes biogénicos infralitorales menos investigados que los circalitorales. El estudio tiene como objetivo contribuir al conocimiento de los arrecifes coralígenos infralitorales describiendo sus comunidades de macroalgas en una gran plataforma rocosa frente a las costas de Toscana, al noroeste del mar Mediterráneo. Un diseño de muestreo multifactorial fue utilizado para describir la estructura de comunidades algales y evaluar la variabilidad del sistema en múltiples escalas espaciales. Se encontró un total de 71 taxones de macroalgas sobre las algas coralinas. Las comunidades de macroalgas estaban bien estructuradas con altos valores de biodiversidad. Los taxones dominantes incluyeron tanto especies fotófilas como esciáfilas, lo que garantizó características peculiares a estas comunidades si se comparan con las típicas comunidades de macroalgas infralitorales y circalitorales de la misma área geográfica. Las comunidades mostraron una variabilidad a pequeña e intermedia escala mayor que a gran escala espacial. Si bien los afloramientos coralígenos infralitorales constituyen un sistema peculiar, aún son poco conocidos y deberían ser objeto no solo de estudios específicos sino también incluidos en programas de monitoreo ambiental

Ecotoxicological properties of ketoprofen and the S(+)‐enantiomer (dexketoprofen): Bioassays in freshwater model species and biomarkers in fish PLHC‐1 cell line

The increased use of non-steroidal anti-inflammatory drugs (NSAIDs) has resulted in their ubiquitous presence in the environment. The toxicological properties of these two widely prescribed NSAIDs, namely - racemic ketoprofen (rac-KP) and its enantiomer S(+)-ketoprofen (dexketoprofen, DKP) were evaluated. Firstly, by acute and chronic toxicity tests using three representative model organisms (Vibrio fischeri, Pseudokirchneriella subcapitata and Ceriodaphnia dubia). Secondly, by evaluating the responses of biotransformation systems and multidrug resistance associated proteins (MRP1/MRP2) using the PLHC-1 fish hepatic cell-line. Toxicity data from both acute and chronic DKP exposure indicated higher sensitivity through inhibition of bioluminescence and algal growth and through increased mortality/immobilization compared to rac-KP exposure. The growth inhibition test showed that rac-KP and DKP exhibited different values for EC50 (240.2 µg/L and 65.6 µg/L, respectively). Furthermore, rac-KP and DKP did not exert cytotoxic effects in PLHC-1 cells, and produced compound-, time- and concentration-specific differential effects on CYP1A and GST levels. For CYP1A, the effects of rac-KP and DKP differed at transcriptional and catalytic level. Exposure to rac-KP and DKP modulated MRP1 and MRP2 mRNA levels and these effects were also dependent on compound, exposure time and concentration of the individual drug. The present study revealed for the first time, the interactions between these NSAIDs and key detoxification systems, and different sensitivity to the racemic mixture compared to its enantiomer. This article is protected by copyright. All rights reserved

Looking for Nano- and Microplastics in Meiofauna Using Advanced Methodologies

: Meiofauna (body size within 30–1000 µm) are the community of microscopic invertebrates that live at the bottom of marine and freshwater ecosystems and play a key role in the food webs of these environments. Several studies have addressed the adverse effects of anthropic stressors on meiofauna; however, data on the presence and impact of plastic debris in wild meiofaunal organisms are scant. Since the amount of microplastic waste in sediments may surge rapidly, ascertaining the ingestion of these xenobiotics by the abundant micrometazoan community is necessary to understand their potential accumulation in aquatic food webs and their hazard to the health of the ecosystem. The absence of documentation in this regard may be due to the difficulty in detecting the small size of the plastic fragments meiofauna may potentially ingest. To overcome this difficulty, we developed an integrated approach based on different microscopic/spectroscopic techniques suitable for detecting plastic particles of sizes down to 200 nm.Meiofauna (body size within 30–1000 m) are the community of microscopic invertebrates that live at the bottom of marine and freshwater ecosystems and play a key role in the food webs of these environments. Several studies have addressed the adverse effects of anthropic stressors on meiofauna; however, data on the presence and impact of plastic debris in wild meiofaunal organisms are scant. Since the amount of microplastic waste in sediments may surge rapidly, ascertaining the ingestion of these xenobiotics by the abundant micrometazoan community is necessary to understand their potential accumulation in aquatic food webs and their hazard to the health of the ecosystem. The absence of documentation in this regard may be due to the difficulty in detecting the small size of the plastic fragments meiofauna may potentially ingest. To overcome this difficulty, we developed an integrated approach based on different microscopic/spectroscopic techniques suitable for detecting plastic particles of sizes down to 200 nm

Novel organ-specific effects of Ketoprofen and its enantiomer, dexketoprofen on toxicological response transcripts and their functional products in salmon.

Racemic ketoprofen (RS-KP) and its enantiomer, dexketoprofen (S(+)-KP) are widely used non-steroidal anti-inflammatory drugs (NSAIDs), and commonly detected in the aquatic environment. The present study has evaluated the toxicological effects of RS-KP and S(+)-KP on biotransformation and oxidative stress responses in gills and liver of Atlantic salmon. Fish were exposed for 10 days using different concentrations of RS-KP (1, 10 and 100 μg/L) and S(+)-KP (0.5, 5 and 50 μg/L). Biotransformation and oxidative stress responses were analysed at both transcript and functional levels. In the gills, significant inhibitory effect at transcriptional and enzymatic levels were observed for biotransformation and oxidative stress responses. On the contrary, biotransformation responses were significantly increased at transcriptional and translational levels in the liver, while the associated enzymatic activities did not parallel this trend and were inhibited and further demonstrated by principal component analysis (PCA). Our findings showed that both compounds produced comparable toxicological effects, by producing organ-specific effect differences. RS-KP and S(+)-KP did not bioaccumulate in fish muscle, either due to rapid metabolism or excretion as a result of their hydrophobic properties. Interestingly, the inhibitory effects observed in the gills suggest that these drugs may not undergo first pass metabolism, that might result to downstream differences in toxicological outcomes

Novel organ-specific effects of Ketoprofen and its enantiomer, dexketoprofen on toxicological response transcripts and their functional products in salmon

Racemic ketoprofen (RS-KP) and its enantiomer, dexketoprofen (S(+)-KP) are widely used non-steroidal anti-inflammatory drugs (NSAIDs), and commonly detected in the aquatic environment. The present study has evaluated the toxicological effects of RS-KP and S(+)-KP on biotransformation and oxidative stress responses in gills and liver of Atlantic salmon. Fish were exposed for 10 days using different concentrations of RS-KP (1, 10 and 100 μg/L) and S(+)-KP (0.5, 5 and 50 μg/L). Biotransformation and oxidative stress responses were analysed at both transcript and functional levels. In the gills, significant inhibitory effect at transcriptional and enzymatic levels were observed for biotransformation and oxidative stress responses. On the contrary, biotransformation responses were significantly increased at transcriptional and translational levels in the liver, while the associated enzymatic activities did not parallel this trend and were inhibited and further demonstrated by principal component analysis (PCA). Our findings showed that both compounds produced comparable toxicological effects, by producing organ-specific effect differences. RS-KP and S(+)-KP did not bioaccumulate in fish muscle, either due to rapid metabolism or excretion as a result of their hydrophobic properties. Interestingly, the inhibitory effects observed in the gills suggest that these drugs may not undergo first pass metabolism, that might result to downstream differences in toxicological outcomes

Bioactive compounds from posidonia oceanica (L.) delile impair malignant cell migration through autophagy modulation

Posidonia oceanica (L.) Delile is a marine plant with interesting biological properties potentially ascribed to the synergistic combination of bioactive compounds. Our previously described extract, obtained from the leaves of P. oceanica, showed the ability to impair HT1080 cell migration by targeting both expression and activity of gelatinases. Commonly, the lack of knowledge about the mechanism of action of phytocomplexes may be an obstacle regarding their therapeutic use and development. The aim of this study was to gain insight into the molecular signaling through which such bioactive compounds impact on malignant cell migration and gelatinolytic activity. The increase in autophagic vacuoles detected by confocal microscopy suggested an enhancement of autophagy in a time and dose dependent manner. This autophagy activation was further confirmed by monitoring pivotal markers of autophagy signaling as well as by evidencing an increase in IGF-1R accumulation on cell membranes. Taken together, our results confirm that the P. oceanica phytocomplex is a promising reservoir of potent and cell safe molecules able to defend against malignancies and other diseases in which gelatinases play a major role in progression. In conclusion, the attractive properties of this phytocomplex may be of industrial interest in regard to the development of novel health-promoting and pharmacological products for the treatment or prevention of several diseases

The effect of temperature on Triclosan and Lead exposed mussels

Interest on the effects of emerging contaminants over aquatic organisms has increased in the last years. Nonetheless, the toxic action of classical natural and anthropogenically-driven metals has also to be monitored, especially because they reflect real environmental situations. For that, in the present study we focused on the effects on the marine mussel Mytilus galloprovincialis of the personal care product Triclosan (TCS) and Lead (Pb), as toxic metal, under separate and co-exposure situations at environmentally relevant concentrations: TCS (1 μg/L) and Pb (50 μg/L). The consideration of an additional factor such as an increase in ambient temperature was also included to provide a forecasted scenario of climate change: from the ambient temperature at actual conditions (17 °C) to a predicted warming situation (22 °C). Water chemical characterization and some physical properties and bioaccumulation of TCS and Pb in mussels at the end of the experiment (28 days) was considered. The parameters followed up comprise the energy related system production (electron transport system) and glycogen and protein reserves. Antioxidant enzymatic defences towards reactive oxygen species (ROS) and the consequences of ROS damage over endogenous lipids (LPO) and proteins (PC). Overall the results suggested only particular responses to chemical exposures at 17 °C whereas at 22 °C the detoxification machinery was set up and this prevented the occurrence of LPO. Nonetheless, PC formation occurred under Pb and TCS + Pb co-exposure at the highest temperature. Due to the complexity of the study: 4 chemical conditions, 2 temperatures and 10 biomarkers considered, a principal component ordination (PCO) analysis was included. The results of this integrative analysis confirmed a clear effect of the temperature, more responsiveness to drugs at 22 °C and in all likelihood due to Pb presence.publishe