Comparative assessment of the acute toxicity of commercial bio-based polymer leachates on marine plankton.

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.

Developmental and biochemical markers of the impact of pollutant mixtures under the effect of Global Climate Change.

This study investigates the combined impact of microplastics (MP) and Chlorpyriphos (CPF) on sea urchin larvae (Paracentrotus lividus) under the backdrop of ocean warming and acidification. While the individual toxic effects of these pollutants have been previously reported, their combined effects remain poorly understood. Two experiments were conducted using different concentrations of CPF (EC10 and EC50) based on previous studies from our group. MP were adsorbed in CPF to simulate realistic environmental conditions. Additionally, water acidification and warming protocols were implemented to mimic future ocean conditions. Sea urchin embryo toxicity tests were conducted to assess larval development under various treatment combinations of CPF, MP, ocean acidification (OA), and temperature (OW). Morphometric measurements and biochemical analyses were performed to evaluate the effects comprehensively. Results indicate that combined stressors lead to significant morphological alterations, such as increased larval width and reduced stomach volume. Furthermore, biochemical biomarkers like acetylcholinesterase (AChE), glutathione S-transferase (GST), and glutathione reductase (GRx) activities were affected, indicating oxidative stress and impaired detoxification capacity. Interestingly, while temperature increase was expected to enhance larval growth, it instead induced thermal stress, resulting in lower growth rates. This underscores the importance of considering multiple stressors in ecological assessments. Biochemical biomarkers provided early indications of stress responses, complementing traditional growth measurements. The study highlights the necessity of holistic approaches when assessing environmental impacts on marine ecosystems. Understanding interactions between pollutants and environmental stressors is crucial for effective conservation strategies. Future research should delve deeper into the impacts at lower biological levels and explore adaptive mechanisms in marine organisms facing multiple stressors. By doing so, we can better anticipate and mitigate the adverse effects of anthropogenic pollutants on marine biodiversity and ecosystem health.

Impact of microplastics and ocean acidification on critical stages of sea urchin (Paracentrotus lividus) early development.

One of the major consequences of increasing atmospheric CO2 is a phenomenon known as ocean acidification. This alteration of water chemistry can modulate the impact on marine organisms of other stressors also present in the environment, such as microplastics (MP). The objective of this work was to determine the combined impact of microplastic pollution and ocean acidification on the early development of Paracentrotus lividus. To study these multi-stressor impacts on development P. lividus the sea urchin embryo test (SET) was used. Newly fertilised embryos of P. lividus were exposed to a control treatment (filtered natural seawater), MP (3000 particles/mL), acidified sea water (pH = 7.6), and a combination of MP and acidification (3000 particles/mL + pH = 7.6). After 48, 72, and 96 h measurements of growth and morphometric parameters were taken. Results showed that ocean acidification and MP cause alterations in growth and larval morphology both before and after the larvae start to feed exogenously. The exposure to MP under conditions of ocean acidification did not produce any additional effect on growth, but differences were observed at the morphological level related to a decrease in the width of larvae at 48 h. Overall, changes in larvae shape observed at three key points of their development could modify their buoyancy affecting their ability to obtain and ingest food. Therefore, ocean acidification and MP pollution might compromise the chances of P. lividus to survive in the environment under future scenarios of global climate change.

Metal and metalloid pollution in shelf sediments from the Gulf of Cádiz (Southwest Spain): Long-lasting effects of a historical mining area.

The Gulf of Cádiz is an area historically affected by acid mine drainage and also by the discharge of two important rivers, the Guadiana and the Guadalquivir. Metal and metalloid (As, Cd, Hg, Pb, Zn, Cu, Cr, Ni, Mn, Fe, Al and Li) concentrations were measured in 33 surface sediment samples, collected in the continental shelf, inside the Ría de Huelva and the Bay of Cádiz, to assess the metal pollution status of this area. Geographical distribution was identified for different groups of metals: Cu, Cd, Zn, Hg and As were mainly associated with discharges of the Tinto and Odiel rivers, which have been historically affected by mining, into the Ría de Huelva. Sediments inside this Ría presented the highest concentrations of the whole area for these metals, and enrichment factors revealed that Hg and Cu pollution spread up to 20 km away from the mouth of this Ría, into the continental shelf. On the contrary, the distribution of Ni, Cr and Mn did not show a clear gradient with distance from a pollution source, and was mainly explained by geochemical factors, such as their association with fine materials. The comparison of metal concentrations with sediment quality guidelines, predicts that adverse ecological effects due to the metal pollution may be occurring in a group of stations located in the northwest corner of the studied area. Local background levels for metals in the Gulf of Cádiz were proposed and the information obtained will be useful to identify those areas where sampling must be intensified in ongoing Marine Strategy Framework Directive (MSFD) monitoring programs. These results corroborate that metal pollution is still a serious problem in the Gulf of Cádiz.

Combined effect of microplastics and global warming factors on early growth and development of the sea urchin (Paracentrotus lividus).

The aim of this work was to estimate the potential risk of the combined effect of global change factors (acidification, temperature increase) and microplastic (MP) pollution on the growth and development of the sea urchin P. lividus. Embryo-larval bioassays were conducted to determine growth and morphology after 48 h of incubation with MP (1000 and 3000 particles/mL); with filtered sea water at pH = 7.6; and with their combinations. A second experiment was conducted to study the effect of pH and MP in combination with a temperature increase of 4 °C compared to control (20 °C). We found that the inhibition of growth in embryos reared at pH = 7.6 was around 75%. Larvae incubated at 3000 MP particles/mL showed a 20% decrease in growth compared to controls. The exposure to MP also induced an increase in the postoral arm separation or rounded vertices. The combined exposure to a pH 7.6 and MP caused a significant decrease of larval growth compared to control, to MP and to pH 7.6 treatments. Morphological alterations were observed in these treatments, including the development of only two arms. Increasing the temperature resulted in an increased growth in control, in pH 7.6 and pH 7.6 + MP3000 treatments, but the relative stomach volume decreased. However, when growth parameters were expressed per Degree-Days the lower growth provoked by the thermal stress was evidenced in all treatments. In this work we demonstrated that MP could aggravate the effect of a decreased pH and that an increase in water temperature generated an additional stress on P. lividus larvae, manifested in a lower growth and an altered development. Therefore, the combined stress caused by ocean warming, ocean acidification, and microplastic pollution, could threaten sea urchin populations leading to a potential impact on coastal ecosystems.

Sediment metal enrichment and ecological risk assessment of ten ports and estuaries in the World Harbours Project.

Ten global harbours were assessed for sediment quality by quantifying the magnitude of anthropogenic change and ecological risk. Anthropogenic change (enrichment) was high for Derwent River and Sydney estuary, moderate for Santander Harbour, Rio de Janeiro and Dublin Port, slight for Hong Kong, minimal for Darwin. All 10 enrichment indices used showed similar results. Derwent River sediment was rated at high ecological risk, followed by Sydney and Santander estuaries with moderate risk. Auckland and Darwin sediments exhibited minimal ecological risk and sediment in the remaining harbours (Dublin, Hong Kong, Ravenna, Ria de Vigo and Rio de Janeiro) were assessed at slight ecological risk. The extraordinary variety of environments and types/quantities/qualities of data investigated resulted in as much a critique and development of methodology, as an assessment of human impact, including unique techniques for elemental normalisation and contaminant classification. Recommendations for an improved technical framework for sediment quality assessment are provided.

Ingestion and contact with polyethylene microplastics does not cause acute toxicity on marine zooplankton.

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.

Critical analysis of the relationship between imposex and butyltin body burden in Nassarius reticulatus and Nucella lapillus.

Imposex is a disorder caused by organotins, mainly tributyltin, which results in the appearance of male sexual characteristics in females of gastropod mollusks. The main objective of this work was to make a critical analysis of the relationship between imposex and butyltin body burdens in Nucella lapillus and Nassarius reticulatus. Specifically, this study evaluates possible additive effects among butyltins, proposes scales of effects based on robust statistical criteria as alternatives to existing ones and defines the body burdens of TBT in N. lapillus and N. reticulatus corresponding to the assessment classes (ACs) of the Vas Deferens Sequence Index (VDSI) established by OSPAR. Data of organotin body burdens and biological effects was retrieved from the ICES Dataset and from scientific literature. All responses, except the percentage of females displaying Imposex (IMPF) in Nucella lapillus, showed a sigmoidal profile regarding to the body burden of mono- (MBT), di- (DBT) and tributyltin and sum of butyltins (SumBTs). TBT and the SumBTs were better indicators of the VDSI or Relative Penis Size Index/Relative Penis Length Index (RPSI/RPLI) responses than MBT or DBT in most cases. From a statistical point of view, RPSI/RPLI and VDSI were better indicators of contamination by TBT than IMPF, although both RPSI and RPLI showed lower sensitivity than VDSI. The model used for describing the joint effect of butyltins provided a statistically significant fitting to the data assuming a null effect for both MBT and DBT for N. lapillus, and a lower toxic contribution of MBT and DBT with respect to TBT for N. reticulatus. RPSI or RPLI values, equivalent to the ACs for VDSI, were proposed as alternative criteria when measuring moderate to high levels of imposex. TBT concentrations in N. reticulatus and N. lapillus tissues, corresponding to the ACs were calculated and provided valuable information for cross-species comparisons.

Fast and selective separation of carbon dioxide from dilute streams by pressure swing adsorption using solid ionic liquids.

The need to create a new approach to carbon capture processes that are economically viable has led to the design and synthesis of sorbents that selectively capture carbon dioxide by physisorption. Solid Ionic Liquids (SoILs) were targeted because of their tunable properties and solid form under operational conditions. Molecular modelling was used to identify candidate SoILs and a number of materials based on the low cost, environmentally friendly acetate anion were selected. The materials showed excellent selectivity for carbon dioxide over nitrogen and oxygen and moderate sorption capacity. However, the rate of capture was extremely fast, in the order of a few seconds for a complete adsorb-desorb cycle, under pressure swing conditions from 1 to 10 bar. This showed the importance of rate of sorption cycling over capacity and demonstrates that smaller inventories of sorbents and smaller process equipment are required to capture low concentration CO2 streams. Concentrated CO2 was isolated by releasing the pressure back to atmospheric. The low volatility and thermal stability of SoILs mean that both plant costs and materials costs can be reduced and plant size considerably reduced.

The use of cryopreserved sea urchin embryos (Paracentrotus lividus) in marine quality assessment.

We have established for first time an ecotoxicological bioassay using cryopreserved sea urchin embryos (Paracentotus lividus) and provided a comparison to the already standardized sea urchin embryo-larval bioassay, using selected (organic and inorganic) pollutants and sediment elutriates from 4 different locations from Ria de Vigo harbour (Galicia, NW Iberian Peninsula). A cryopreservation protocol was designed in order to enable the successful cryopreservation and cryobanking of gametes and embryos to be used for marine quality assessment and ensure the accessibility to high quality reproductive material all year round, as an option to conditioning adults for out of season reproduction. The calculated EC50 using the cryopreserved blastula was 53.7 µg L(-1) for copper, 81.0 µg L(-1) for lead, 300.6 µg L(-1) for BP-3 and 300.6 µg L(-1) for 4-MBC. The sensitivity of the classic sea urchin embryo-larval bioassay was compared with the bioassay conducted with cryopreserved blastula. The results showed that the use of cryopreserved blastula bioassay allows detecting lower concentrations of pollutants in comparison with the classic bioassay.

The link between descriptors 8 and 9 of the Marine Strategy Framework Directive: lessons learnt in Spain.

The aim of this note is to discuss the relevance of the interaction/integration of monitoring of contaminants for the protection of the marine environment and for human health safety (descriptors 8 and 9, respectively) within the Marine Strategy Framework Directive (MSFD). The identification of possible relations between contaminant levels in sediments and tissues of fish and other seafood, as well as the association of those levels to pollution sources, are major challenges for marine researchers. The Spanish initial assessment in the North-East Atlantic marine region was used as an example to show some gaps and loopholes when dealing with the relationship between descriptors 8 and 9. The main problem to deal with is that monitoring programmes intended for the assessment of marine environmental quality and for human health safety usually apply different approaches and methodologies, and even different tissues are analysed in some species (mainly fish). It is therefore recommended to make a profound revision of current sampling strategies, procedures and methodologies, including the selection of target species and tissues and to improve the traceability of samples of fish and other seafood for human consumption. On the other hand, despite the scope of descriptor 9 which is limited to commercially relevant species, this fact should not be an obstacle in the application of the 'ecosystem approach' within the MSFD. In order to appropriately solve these shortcomings, an information exchange system between authorities dealing with descriptors 8 and 9 should be strongly encouraged for the next steps of the MSFD's implementation.

Sea urchin (Paracentrotus lividus) cryopreserved embryos survival and growth: effects of cryopreservation parameters and reproductive seasonality.

BACKGROUND: The cryopreservation of embryos can be a powerful biotechnological tool to supply all year-round biological material for sea urchin aquaculture production. This study investigates different methodological and biological factors that may affect the result of the cryopreservation process of sea urchin (Paracentrotus lividus) embryos. Our data indicate that neither embryo density nor the use of different cryopreservation containers presented effect on the cryopreservation outcome. Contrary to other marine invertebrates, for sea urchin embryo cryopreservation ultrapure water cannot be used as CPA solvent, yielding zero survival. After studying the reproductive parameters along the reproductive season, we found a positive correlation between both male and female Condition Index (C.I.), and between the oocyte weight and C.I. Both the histology study of female gonads and the C.I. variation, suggest that the sea urchin natural spawning period in the Ría de Vigo occurs between June and July. We found no correlation between any of the reproductive parameters monitored and the cryopreservation outcome.

Glutathione S-transferase, glutathione peroxidase and acetylcholinesterase activities in mussels transplanted to harbour areas.

As part of an integrative monitoring campaign involving water and sediment chemistry, in situ bioassays, and mussel bioaccumulation and biomarkers, Mytilus galloprovincialis mussels of standard size were transplanted from a clean location to five sites in two important harbours from the Atlantic coast of Spain (Vigo and Pasaia). After a 30-day field exposure, the concentrations of major contaminants (trace metals, polychlorinated biphenyls and polycyclic aromatic hydrocarbons) accumulated in mussel tissues were measured at each site, and a mussel bioaccumulation index (MBI) was calculated. The enzymatic activity levels of glutathione S-transferase (GST), glutathione peroxidase (GPx) and acetylcholinesterase (AChE) were quantified in the gills of transplanted mussels (n=12). Mussels from the most polluted sites consistently exhibited significantly higher GST and GPx activities compared to the control site, whereas AChE activity was significantly inhibited. The responses of the GST and GPx activities were related to MBI, trace metals and PAH concentrations in mussels, whereas AChE activity was related to the trace metals concentrations in mussels. The above results suggest that GST and AChE activities can be used as potential biomarkers for active monitoring in marine coastal ecosystems. However, at this moment, GPx activity is not robust enough to be applicable to harbour areas.

Comparative cryopreservation study of trochophore larvae from two species of bivalves: Pacific oyster (Crassostrea gigas) and Blue mussel (Mytilus galloprovincialis).

Oysters and mussels are among the most farmed species in aquaculture industry around the world. The aim of this study was to test the toxicity of cryoprotective agents to trochophore larvae from two different species of bivalves and develop an improved cryopreservation protocol to ensure greater efficiency in the development of cryopreserved trochophores (14 h old oyster larvae and 20 h old mussel larvae) to normal D-larvae for future developments of hatchery spat production. The cryopreservation protocol producing the best results for oyster trochophores (60.0 ± 6.7% normal D-larvae) was obtained by holding at 0 °C for 5 min then cooling at 1 °C min(-1) to -10 °C and holding for 5 min before cooling at 0.5 °C to -35 °C, holding 5 min and then plunging into liquid nitrogen (LN), using 10% ethylene glycol. For mussel experiments, no significant differences were found when cooling at 0.5 °C min(-1) or at 1 °C min(-1) for CPA combinations with 10% ethylene glycol and at 0.5 °C min(-1). Using these combinations, around half of trochophores were able to develop to normal D-larvae post-thawing (48.9 ± 7.6% normal D-larvae).

[Placement of a bronchial blocker through the I-gel supraglottic airway device for single-lung ventilation: preliminary study]. / Ventilación unipulmonar con bloqueador bronquial a través del dispositivo supraglótico I-gel. Estudio preliminar.

To describe the use of the I-gel supraglottic airway device when placing a bronchial blocker for single-lung ventilation, as applied in a preliminary study to explore the feasibility of adopting the technique with appropriate, selected patients undergoing certain thoracic surgery procedures. We used the technique for single-lung ventilation in 25 patients who required isolation of a lung for a variety of thoracic surgical procedures. A bronchial blocker was placed under direct visualization through a fiberoptic bronchoscope and the I-gel supraglottic device. The I-gel mask allowed us to establish a reliable, safe seal of the airway. For an anesthetist with sufficient experience in managing a flexible fiberoptic bronchoscope, it was possible to carry out all procedures without remarkable anesthetic or surgical events. Single-lung ventilation achieved by introducing a bronchial blocker through the I-gel supraglottic device can facilitate safe, effective management of selected patients who must undergo certain thoracic surgery procedures.

Ventilación unipulmonar con bloqueador bronquial a través del dispositivo supraglótico I-gel. Estudio preliminar / Placement of a bronchial blocker through the I-gel supraglottic airway device for singlelung ventilation: preliminary study

El objetivo es describir la técnica del ventilación unipulmonar utilizando el dispositivo supraglótico i-gel y un bloqueador bronquial como estudio preliminar para su posible aplicación futura en el manejo de determinados pacientes y procedimientos quirúrgicos torácicos adecuadamente seleccionados. Se describe la ventilación unipulmonar realizada en 25 pacientes sometidos a diferentes procedimientos de cirugía torácica en los que era necesario el aislamiento pulmonar selectivo. Éste se realizó con un bloqueador bronquial colocado, mediante visión directa fibrobroncoscópica, a través del dispositivo supraglótico i-gel. Gracias al diseño de la mascarilla i-gel, el cual permite un sellado fiable y seguro de la vía aérea, y a una adecuada experiencia en el manejo del fibrobroncoscopio óptico flexible se consiguió llevar a cabo la totalidad de los procedimientos sin incidencias reseñables tanto desde el punto de vista anestésico como quirúrgico. La ventilación unipulmonar conseguida con bloqueador bronquial, introducido a través del dispositivo supraglótico i-gel, puede ser una alternativa segura y eficaz para el manejo de pacientes que, adecuadamente seleccionados, sean sometidos a determinados procedimientos torácicos(AU)

To describe the use of the I-gel supraglottic airway device when placing a bronchial blocker for single-lung ventilation, as applied in a preliminary study to explore the feasibility of adopting the technique with appropriate, selected patients undergoing certain thoracic surgery procedures. We used the technique for single-lung ventilation in 25 patients who required isolation of a lung for a variety of thoracic surgical procedures. A bronchial blocker was placed under direct visualization through a fiberoptic bronchoscope and the I-gel supraglottic device. The I-gel mask allowed us to establish a reliable, safe seal of the airway. For an anesthetist with sufficient experience in managing a flexible fiberoptic bronchoscope, it was possible to carry out all procedures without remarkable anesthetic or surgical events. Single-lung ventilation achieved by introducing a bronchial blocker through the I-gel supraglottic device can facilitate safe, effective management of selected patients who must undergo certain thoracic surgery procedures(AU)