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Simple Summary: This research investigated microplastic ingestion in two marine crustacean species of high commercial importance, namely the Giant Red Shrimp Aristaeomorpha foliacea and the Deep-Water Rose Shrimp Parapenaeus longirostris. The primary purpose of this study was to better understand how these species are affected by microplastic pollution, a growing concern in the marine environment worldwide. Based on stable isotope analysis of muscle tissue and on the examination of their gastrointestinal tracts, it was found that the trophic niche of the two species is similar, but the type of particles ingested differed significantly in terms of shape, colour, size class, and polymer. These outcomes shed light on the pervasive impact of microplastic contamination on marine wildlife, emphasising potential threats to consumers at higher levels of the food web. A better knowledge of pathways that microplastics follow through marine food webs is crucial for understanding the ecological implications posed by this emerging contaminant. Increasing plastic contamination poses a serious threat to marine organisms. Microplastics (MPs) ingestion can represent a risk for the organism itself and for the ultimate consumer. Through the analysis of the gastrointestinal tract, coupled with stable isotope analysis on the muscle tissue, this study provides insights into the relationship between MPs pollution and ecology in two commercial marine species caught in the Central Tyrrhenian Sea: Aristaeomorpha foliacea and Parapenaeus longirostris. Stable isotope analysis was conducted to determine the trophic position and the trophic niche width. The gastrointestinal tracts were processed, and the resultant MPs were analysed under FT-IR spectroscopy to estimate the occurrence, abundance, and typology of the ingested MPs. The trophic level of the species was similar (P. longirostris TP = 3 ± 0.10 and A. foliacea TP = 3.1 ± 0.08), with an important trophic niche overlap, where 38% and 52% of P. longirostris and A. foliacea has ingested MPs, respectively. Though species-level differences may not be evident regarding MP's abundance per individual, a high degree of dissimilarity was noted in the typologies of ingested particles. This research provides valuable insights into how MPs enter marine trophic webs, stressing that isotopic niche analysis should be combined with other methods to explain in detail the differences in MPs ingestion. [ABSTRACT FROM AUTHOR]

Sponge farming has been experimentally performed for more than 100 years, with early attempts mainly devoted for the supply of bath sponges and for ornamental purposes. During the last decades, sponge farming has been proposed to produce biomass specifically for those species from which many structurally diverse bioactive compounds were isolated, frequently present in a low concentration that limits their commercial production. This point is very important because it offers an environmental-friendly approach for the use of sponges as a source of natural compounds for pharmacological, cosmeceutical, and nutraceutical industries. In addition, sponges can have an ecological role as filter-feeding animals with a great significance in marine benthic communities. Thanks to their aquiferous system, they can filter large amounts of sea water, retaining up to 80% of suspended particles, resulting in a good system to bioremediate the marine environment from different contaminants. Remarkably, few attempts at integrating aquaculture systems were performed by combining the increase in sponge biomass and their use for bioremediation, showing impressive results and opening new possibilities in the aquaculture sector. This review concerns both in situ and lab-based aquaculture methods for the production of sponge biomass and for the sponge-related bioremediation of the marine environment focusing on microorganisms and contaminants (heavy metals, pesticides, microplastics, and others). Moreover, a first overview about integrated aquaculture combining biomass increase and bioremediation, as a challenging perspective for marine biotechnologies, is included. [ABSTRACT FROM AUTHOR]

Marine environmental conservation and tourist exploitation are often in conflict, particularly where anthropogenic pressure is greatest, such as along the coasts of the Mediterranean Sea. A case in point is the accumulation of beach-cast seagrass, a typical feature of the Mediterranean Sea that is nowadays perceived as an "obstacle" to tourist activities and thus treated and removed as waste, leading to environmental impacts. In this paper, we analyzed the legislative context at the Mediterranean basin level and the contribution of twenty virtuous research projects related to the topic. In our opinion, the main benefits for the beach–dune ecosystem would be generated by the use of seagrass banquettes directly within the beach system (temporary displacement, creating beach walkways, dune consolidation), while their uses outside the beach system (agricultural and farm solutions—compost and bedding) should be considered as alternative solutions for a circular economy, in case of consistent biomass deposits along the shores. In this perspective, we support the "Ecological Beach" model which integrates most of the science-derived solutions addressed in this study. This model provides good practices that can be usefully spread and shared along Mediterranean coasts: to achieve this result, it is necessary to create a regional or Mediterranean network involving local communities and stakeholders. [ABSTRACT FROM AUTHOR]

Plastic pollution is a distinctive element of the globalized world. In fact, since the 1970s the expansion and use of plastics, particularly in the consumer and commercial sectors, has given this material a permanent place in our lives. The increasing use of plastic products and the wrong management of end-of-life plastic products have contributed to increasing environmental pollution, with negative impacts on our ecosystems and the ecological functions of natural habitats. Nowadays, plastic pollution is pervasive in all environmental compartments. As aquatic environments are the dumping points for poorly managed plastics, biofouling and biodegradation have been proposed as promising approaches for plastic bioremediation. Known for the high stability of plastics in the marine environment, this represents a very important issue to preserve marine biodiversity. In this review, we have summarized the main cases reported in the literature on the degradation of plastics by bacteria, fungi, and microalgae and the degradation mechanisms involved, to highlight the potential of bioremediation approaches to reduce macro and microplastic pollution. [ABSTRACT FROM AUTHOR]

Within EU approval policies, most dispersant ecotoxicity testing considers lethal concentrations for marine adult species, overlooking the embryotoxicological effects. Here we studied the ecotoxicity of two commercial dispersant formulations (dispersant A and B) on the embryogenesis of the ascidian Ciona robusta. Embryotoxicity and phenotypic alterations stated that dispersant B resulted more toxic than A (EC50 value of 44.30 and 160 μg mL−1, respectively) and induced severe larvae malformations at lower concentrations. Furthermore, the analysis of genes involved in different cellular response pathways indicated that those belonging to biotransformation were upregulated by dispersant A treatment, likely related to the presence of hydrocarbons. Instead, dispersant B induced cas8 gene downregulation, probably as a result of the prolonged exposure to mixture components. Our preliminary findings support the use of the C. robusta embryotoxicity test as a valuable tool for dispersant approval procedures, by providing sub-lethal responses on marine invertebrates closely related to vertebrates. [ABSTRACT FROM AUTHOR]

Nanoplastics are considered contaminants of emerging concern at the global scale. The recent evidence of their occurrence in seawater from the Mediterranean Sea calls for a thorough evaluation of their impact on marine life and in particular on vulnerable life stages such as planktonic embryos. Here, we investigated the impact of increasing nominal concentrations of 50 nm amino-modified (PS-NH2) and 60 nm carboxy-modified (PS-COOH) polystyrene nanoparticles (PS NPs) on the embryonic development of the ascidian Ciona robusta (phylum Chordata), a common benthic invertebrate living in Mediterranean coastal areas with the peculiarity of being an early chordate developmental model. A strong agglomeration of PS-COOH (approx. 1 µm) was observed in natural sea water (NSW) already at time 0, while PS-NH2 resulted still monodispersed (approx. 130 nm) but largely aggregated after 22 h with a microscale dimension similar to those negatively charged. However, their effect on C. robusta embryos development largely differed at 22 h: PS-COOH did not affect larvae phenotypes nor their development, while PS-NH2 caused a dose-dependent effect (EC50 (22 h) of 7.52 μg mL−1) with various degrees of phenotype malformations (from mild to severe) and impairment of larval swimming. Embryos (up to 30%) exposed to 15 µg mL−1 PS-NH2 resulted not developed and the majority was unable to hatch. Calculated PS-NH2 EC50 resulted higher than those available for other marine invertebrate species, suggesting a protective role of the egg envelopes surrounding C. robusta embryos toward nanoplastics exposure. [ABSTRACT FROM AUTHOR]

Copper oxide nanoparticles (CuO NPs) are extensively used in various industrial and commercial applications. Despite their wide application may lead to the contamination of marine ecosystem, their potential environmental effects remain to be determined. Toxicity assessment studies have primarily focused on investigating the effects of CuO NPs on fertilization success and embryo development of different sea urchin species while the impact on sperm quality have never been assessed. In this line, this study aims to assess the effects of CuO NPs on the spermatozoa of the sea urchin Paracentrotus lividus . After sperm exposure to CuO NPs, biomarkers of sperm viability, cytotoxicity, oxidative stress, and genotoxicity as well as morphology were evaluated. Results showed that CuO NPs exposure decreased sperm viability, impaired mitochondrial activity and increased the production of reactive oxygen species (ROS) and lipid peroxidation. Furthermore, CuO NPs exposure caused DNA damage and morphological alterations. Together with the antioxidant rescue experiments, these results suggest that oxidative stress is the main driver of CuO NP spermiotoxic effects. The mechanism of toxicity is here proposed: the spontaneous generation of ROS induced by CuO NPs and the disruption of the mitochondrial respiratory chain lead to production of ROS that, in turn, induce lipid peroxidation and DNA damage, and result in defective spermatozoa up to induce sperm cytotoxicity. Investigating the effects of CuO NPs on sea urchin spermatozoa, this study provides valuable insights into the mechanism of reproductive toxicity induced by CuO NPs. [ABSTRACT FROM AUTHOR]

The role of diethylene glycol (DEG) as a co-solvent for selected organic and inorganic pollutants adsorbed onto the particulate matter in produced formation water (PFW) from offshore gas platforms is thoroughly evaluated. Artificial seawater samples were spiked with certified sediments containing several polycyclic aromatic hydrocarbons (PAH) and metals. Aliquots (1 L) containing no DEG and DEG at 3500 and 5000 mg L[sup -1] were kept in static and dynamic modes for 24 h before analysis to allow sufficient partitioning time between solid and liquid phases for the selected analytes. The Italian legislation on this matter sets 3500 mg L[sup -1] as the highest concentration for DEG in PFW. In our experiments, concentrations equal to and above the set limit were chosen to enhance any possible co-solvent effect. Real PFW samples were also analysed, both with and without DEG. The analyses were conducted by using GC-MS for the PAH, and ICP-MS for the metals. A minor co-solvent effect was observed for low-molecular-weight PAH in the artificial seawater in static mode. Among metals, only iron showed an increase in solubility in the presence of DEG, demonstrating the co-solvent effect of DEG. The experiments in dynamic mode revealed no increase in the solubility of any other analytes in the liquid phase compared with static mode. [ABSTRACT FROM AUTHOR]

Bacteria are used in ecotoxicology for their important role in marine ecosystems and their quick, reproducible responses. Here we applied a recently proposed method to assess the ecotoxicity of nanomaterials on the ubiquitous marine bacterium Vibrio anguillarum, as representative of brackish and marine ecosystems. The test allows the determination of 6-h EC50 in a wide range of salinity, by assessing the reduction of bacteria actively replicating and forming colonies. The toxicity of copper oxide nanoparticles (CuO NPs) at different salinities (5-20-35 ‰) was evaluated. CuSO4 5H2O and CuO bulk were used as reference toxicants (solubility and size control, respectively). Aggregation and stability of CuO NP in final testing dispersions were characterized; Cu2+ dissolution and the physical interactions between Vibrio and CuO NPs were also investigated. All the chemical forms of copper showed a clear dose-response relationship, although their toxicity was different. The order of decreasing toxicity was: CuSO2 5H2O > CuO NP > CuO bulk. As expected, the size of CuO NP aggregates increased with salinity and, concurrently, their toxicity decreased. Results confirmed the intrinsic toxicity of CuO NPs, showingmodest Cu2+ dissolution and no evidence of CuO NP internalization or induction of bacterial morphological alterations. This study showed the V. anguillarum bioassay as an effective tool for the risk assessment of nanomaterials in marine and brackish environments. [ABSTRACT FROM AUTHOR]

A research project has been performed to the request of the RAMOGE Executive Secretariat to identify differences between dispersant approval procedures in France and Italy and propose ways to harmonize them. A collaborative study has been conducted by CEDRE (Centre of Documentation, Research and Experimentation on Accidental Water Pollution) and ISPRA (Italian Institute for Environmental Protection and Research) to: a) compare current approval procedures in Italy and France with identification of differences and commonalities; b) carry out toxicity tests using both procedures on two selected dispersants; c) propose a common approach between Italy and France. The results showed that, because of the differences in ecotoxicological tests and in the evaluation criteria used, the outcomes on the same products could be different in Italy and in France. Both tested dispersants met the French requirements for approval (LC 50 ≥ 10 times reference toxicant), while only one dispersant met the Italian approval criterion (EC 50 > 10 mg/L). A possible way of harmonizing the approval procedures could be to increase the number of test organisms in the French procedure, which currently only uses one crustacean species. Furthermore, a common criterion for toxicity assessment should be discussed and agreed. [ABSTRACT FROM AUTHOR]

Swimming speed alteration and mortality assays with the marine crustacean Artemia franciscana were carried out. EC 50 and LC 50 values after 24–48 h exposures were calculated for two reference toxicants, copper sulphate pentahydrate (CuSO 4 ·5H 2 O) and Sodium Dodecyl Sulphate (SDS), and an ecotoxicological concern organic compound, Diethylene Glycol (DEG). Different end-points have been evaluated, in order to point out their sensitivity levels. The swimming speed alteration (SSA) was compared to mortality values and also to the hatching rate inhibition (literature data). SSA resulted to be more sensitive than the mortality and with a sensitivity comparable to (or even higher than) the hatching rate endpoint. [ABSTRACT FROM AUTHOR]

There is not any standardization of when or how guidelines are applied to biological effect data in a sedi-ment quality assessment. The Italian national law applies the Worst Case method that could be too conservative and not fully representative of the potential effects on the real aquatic community. It would be better to integrate the responses of a battery test in the form of a toxicity syn-thetic index. This manuscript describes the results of a battery of toxicity tests (bacteria, algae and sea urchins) carried out on sediment elutriates from multiple environmental sam-pling sites (Tyrrhenian Sea, Italy), and compares different frameworks for integration of the data. The objective was to determine the most appropriate of three data integration strategies for sediment ecotoxicological assessment: a) Worst Case, b) Qualitative Assessment, and c) Quantita-tive Assessment. The Worst Case considers the highest toxic effect, in-dependently from numbers and types of tests carried out, typology of the test matrix, and endpoint. The Qualitative Assessment classifies the sediment toxicity considering only the number of significant toxic effects. The Quantitative Assessment takes into account several macro-descriptors, such as the type of endpoints and the relevance of the environmental matrices. We observed that: a) Worst Case and Qualitative As-sessment do not give any details about the tests; b) the Qualitative Assessment often underestimates the toxic effects; c) the Quantitative Assessment provides a number easy to read as the Worst Case but taking into considera-tion several factors that the Worst Case does not cover. [ABSTRACT FROM AUTHOR]

Semi-permeable devices (SPMDs) are membranes widely used in monitoring studies for their capability to sample passively hydrophobic compounds. SPMDs were used in a Mediterranean lagoon in order to investigate the partitioning of PAHs in sediments and their potential fugacity. A SPMD was placed for 30 days at 4-m depth in the south-eastern part of the Berre lagoon (Marseille, France), and it supplied a short time-integrated measure of 15 PAH concentrations.PAHs were partitioned between SPMD and sediment according to their molecular weight: low molecular weight PAHs were quantified in higher concentration in SPMD, while those of high molecular weight were more abundant in superficial sediments. Fugacity was higher than 1 for most PAHs, with the exception of those with higher molecular weight. Therefore, the flux of these organic contaminants was from sediment to water. [ABSTRACT FROM AUTHOR]

European legislative framework supports a multidisciplinary strategy of environmental monitoring because the environment is a complex system of abiotic and biotic interactions, and it should not be studied and protected by looking at one single aspect. The resulting heterogeneous data request to be carefully processed, and the application of Weight of Evidence (WOE) approaches is, thereby, an integrated validated tool. In this perspective, the present study aims to: (i). apply a specific model (Sediqualsoft) based on the WOE approach for processing multidisciplinary data related to four Lines Of Scientific Evidence (LOEs: chemical analyses, ecotoxicological bioassays, bioaccumulation tests and biomarkers) regarding sediments from an area of the Adriatic Sea; (ii). evaluate the usefulness of this specific integrated approach to estimate the potential environmental hazard due to the presence of gas production platforms respect to the traditional approach of sediment chemical characterization. This latter recognized a more contaminated area within 100 m of the platforms in which the Sediqualsoft model showed the presence of a chemical hazard, ranging from moderate to severe, and identified the contaminants (e.g., some metals, benzo(a)pyrene and acenaphthene) most responsible for it. A significant hazard also appeared in some of the sampled stations by analyzing the LOEs dedicated to the biological responses. The choice of different reference values (regulatory limits, threshold values or concentrations measured in the control area) influenced only the chemical hazard but not the overall integration with other LOEs, showing a moderate hazard for the majority of stations. Here, the concentrations measured in a control area are firstly proposed as possible reference values in Sediqualsoft model applications; this could be of particular relevance when Sediment Quality Guidelines are not available for all the measured substances. Moreover, the limitations of a conventional pass-to-fail approach or worst-case scenario were overcoming interpreting whole chemical and ecotoxicological results. All data analyzed and discussed confirm Sediqualsoft as a suitable tool for processing environmental data, including those first processed here on a monitoring scenario of gas platforms that discharge Produced Water into the sea. [ABSTRACT FROM AUTHOR]

Microbes and seagrass establish symbiotic relationships constituting a functional unit called the holobiont that reacts as a whole to environmental changes. Recent studies have shown that the seagrass microbial associated community varies according to host species, environmental conditions and the host's health status, suggesting that the microbial communities respond rapidly to environmental disturbances and changes. These changes, dynamics of which are still far from being clear, could represent a sensitive monitoring tool and ecological indicator to detect early stages of seagrass stress. In this review, the state of art on seagrass holobiont is discussed in this perspective, with the aim of disentangling the influence of different factors in shaping it. As an example, we expand on the widely studied Halophila stipulacea's associated microbial community, highlighting the changing and the constant components of the associated microbes, in different environmental conditions. These studies represent a pivotal contribution to understanding the holobiont's dynamics and variability pattern, and to the potential development of ecological/ecotoxicological indices. The influences of the host's physiological and environmental status in changing the seagrass holobiont, alongside the bioinformatic tools for data analysis, are key topics that need to be deepened, in order to use the seagrass-microbial interactions as a source of ecological information. [ABSTRACT FROM AUTHOR]

The accumulation of Posidonia oceanica dead leaves on the beaches of the Mediterranean shores is a natural phenomenon. They are either temporary or permanent structures (banquettes) and represent a valuable resource, with important ecosystem functions including coastal protection against erosion. Nevertheless, the perception of these plant accumulations by the different stakeholders (beach managers, local administrations and tourists) is often negative; they consider these deposits a malevolent waste to be removed, rather than a natural and valuable component of the coastline. We propose an integrated/beneficial management model for posidonia deposits, called ECOLOGICAL BEACH, firstly proposed in France, and recently implemented and applied in Italy. The model promotes the preservation of posidonia beach casts on site, with a balanced coexistence of natural and anthropic elements. The model fosters the several important ecosystem services of the beach casts and contributes to coastal preservation. To successfully spread the model, several activities must be implemented: a regulatory framework, the collection of data about the occurrence of beach casts, management protocols and educational programs. The most important activity is the educational one, based on the dissemination of the ecological and economic value of the beach casts, aimed at switching the perception of this phenomenon towards positive appraisal. [ABSTRACT FROM AUTHOR]

A harmonized and integrated approach for monitoring and assessment of contamination, including hydrocarbon exploitation one, is required both by Marine Strategy Framework Directive (MSFD) at EU level and by the Ecosystem Approach (EcAp) program of the Barcelona Convention at Mediterranean level. A broad review of protocols of environmental impact assessment (EIA) procedures, monitoring and decommissioning of offshore platforms adopted by EU and non-EU countries along the Adriatic-Ionian seas was carried out in the framework of the Interreg offshore platforms in Adriatic-Ionian (ADRION) project HarmoNIA (Harmonization and networking for contaminant assessment in the Ionian and Adriatic Seas). The comparison of information provided by six ADRION countries and the application of a harmonized and integrated approach has highlighted specific challenges for managing offshore platform impacts emerged at ADRION level: (i) need of the same legislative level (the Offshore Protocol of Barcelona Convention is not ratified by all countries); (ii) set up of a task force of ADRION experts for discussing critical issues related to impacts of offshore platforms; (iii) harmonization, at the regional level, of EIA procedures, monitoring and decommissioning; (iv) need of an agreed and common list of recommended parameters to monitor in water, sediment and biota for the assessment of impacts due to platform installations and PFW discharges. [ABSTRACT FROM AUTHOR]

Oxylipins are diatom-derived secondary metabolites, deriving from the oxidation of polyunsatured fatty acids that are released from cell membranes after cell damage or senescence of these single-celled algae. Previous results revealed harmful toxic effects of polyunsaturated aldehydes (PUAs) and hydroxyacids (HEPEs) on sea urchin Paracentrotus lividus embryonic development by testing individual compounds and mixtures of the same chemical group. Here, we investigated the combined effects of these compounds on sea urchin development at the morphological and molecular level for the first time. Our results demonstrated that oxylipin mixtures had stronger effects on sea urchin embryos compared with individual compounds, confirming that PUAs induce malformations and HEPEs cause developmental delay. This harmful effect was also confirmed by molecular analysis. Twelve new genes, involved in stress response and embryonic developmental processes, were isolated from the sea urchin P. lividus; these genes were found to be functionally interconnected with 11 genes already identified as a stress response of P. lividus embryos to single oxylipins. The expression levels of most of the analyzed genes targeted by oxylipin mixtures were involved in stress, skeletogenesis, development/differentiation, and detoxification processes. This work has important ecological implications, considering that PUAs and HEPEs represent the most abundant oxylipins in bloom-forming diatoms, opening new perspectives in understanding the molecular pathways activated by sea urchins exposed to diatom oxylipins. [ABSTRACT FROM AUTHOR]

Oxylipins such as polyunsaturated aldehydes (PUAs) and hydroxyacids (HEPEs) are signaling molecules derived from the oxidation of polyunsaturated fatty acids. They are common in diatoms that constitute a major group of microalgae in freshwater and oceanic ecosystems. Although HEPEs represent the most common oxylipins produced by diatoms, little information is available on their effects on marine invertebrates, and most of the information has been obtained by testing individual HEPEs. Our previous studies reported that four hydroxyacids, i.e., 5-, 9-, 11-, and 15-HEPE, were able to induce malformations and a marked developmental delay in sea urchin Paracentrotus lividus embryos, which had not been reported for other oxylipins. Here, we tested a mixture of 5-, 9-, 11-, and 15-HEPE at different concentrations for the first time. The results showed that mixtures of HEPEs have synergistic effects that are much more severe compared to those of individual HEPEs: The HEPE mixtures induced malformations in sea urchin embryos at lower concentrations. Increasing HEPE mixture concentrations induced a marked increase in the number of delayed embryos, until all embryos were delayed at the highest concentration tested. At the molecular level, the HEPE mixtures induced variations in the expression of 50 genes involved in different functional processes, mainly down-regulating these genes at the earliest stages of embryonic development. These findings are ecologically significant, considering that during diatom blooms, sea urchins could accumulate HEPEs in concentrations comparable to those tested in the present study. [ABSTRACT FROM AUTHOR]

Diethylene glycol (DEG) is extensively used on offshore gas platforms to prevent the hydrate formation during the gas–water separation process and to inhibit corrosion events. This chemical might enter in the marine environment via the produced formation water (PFW) discharge. In this study, a new approach was applied to the investigation of the DEG content in PFW discharges and seawater samples from four gas installation platforms in the Adriatic Sea (Italy). The method includes an off-line solid-phase extraction/pre-concentration technique, followed by a nanoscale flow injection/direct-electron ionization (EI) mass spectrometric analysis. Direct-EI is a novel and miniaturized interface for directly coupling a liquid chromatograph with an electron ionization mass spectrometer. The capability to acquire EI spectra, and to operate in selected ion monitoring mode during actual sample analyses, allowed a precise quantification of DEG with a method limit of detection of 31μg/l. In addition, a careful evaluation of the matrix effect showed that, as opposed to electrospray ionization, the response of the Direct-EI interface was not affected by sample interferences. [Copyright &y& Elsevier]

Increasing plastic contamination poses a serious threat to marine organisms. Microplastics (MPs) ingestion can represent a risk for the organism itself and for the ultimate consumer. Through the analysis of the gastrointestinal tract, coupled with stable isotope analysis on the muscle tissue, this study provides insights into the relationship between MPs pollution and ecology in two commercial marine species caught in the Central Tyrrhenian Sea: Aristaeomorpha foliacea and Parapenaeus longirostris . Stable isotope analysis was conducted to determine the trophic position and the trophic niche width. The gastrointestinal tracts were processed, and the resultant MPs were analysed under FT-IR spectroscopy to estimate the occurrence, abundance, and typology of the ingested MPs. The trophic level of the species was similar ( P. longirostris TP = 3 ± 0.10 and A. foliacea TP = 3.1 ± 0.08), with an important trophic niche overlap, where 38% and 52% of P. longirostris and A. foliacea has ingested MPs, respectively. Though species-level differences may not be evident regarding MP's abundance per individual, a high degree of dissimilarity was noted in the typologies of ingested particles. This research provides valuable insights into how MPs enter marine trophic webs, stressing that isotopic niche analysis should be combined with other methods to explain in detail the differences in MPs ingestion.

Bacteria are an important component of the ecosystem, and microbial community alterations can have a significant effect on biogeochemical cycling and food webs. Toxicity testing based on microorganisms are widely used because they are relatively quick, reproducible, cheap, and are not associated with ethical issues. Here, we describe an ecotoxicological method to evaluate the biological response of the marine bacterium Vibrio anguillarum. This method assesses the acute toxicity of chemical compounds, including new contaminants such as nanoparticles, as well as environmental samples. The endpoint is the reduction of bacterial culturability (i.e., the capability to replicate and form colonies) due to exposure to a toxicant. This reduction can be generally referred to as mortality. The test allows for the determination of the LC50, the concentration that causes a 50% decrease of bacteria actively replicating and forming colonies, after a 6 h exposure. The culturable bacteria are counted in terms of colony forming units (CFU), and the "mortality" is evaluated and compared to the control. In this work, the toxicity of copper sulphate (CuSO4) was evaluated. A clear dose-response relationship was observed, with a mean LC50 of 1.13 mg/L, after three independent tests. This protocol, compared to existing methods with microorganisms, is applicable in a wider range of salinity and has no limitations for colored/turbid samples. It uses saline solution as the exposure medium, avoiding any possible interferences of growth medium with the investigated contaminants. The LC50 calculation facilitates comparisons with other bioassays commonly applied to ecotoxicological assessments of the marine environment.

Our research activities target the use of biological methods for the evaluation of environmental quality, with particular reference to saltwater/brackish water and sediment. The choice of biological indicators must be based on reliable scientific knowledge and, possibly, on the availability of standardized procedures. In this article, we present a standardized protocol that used the marine crustacean Artemia to evaluate the toxicity of chemicals and/or of marine environmental matrices. Scientists propose that the brine shrimp (Artemia) is a suitable candidate for the development of a standard bioassay for worldwide utilization. A number of papers have been published on the toxic effects of various chemicals and toxicants on brine shrimp (Artemia). The major advantage of this crustacean for toxicity studies is the overall availability of the dry cysts; these can be immediately used in testing and difficult cultivation is not demanded. . Cyst-based toxicity assays are cheap, continuously available, simple and reliable and are thus an important answer to routine needs of toxicity screening, for industrial monitoring requirements or for regulatory purposes. The proposed method involves the mortality as an endpoint. The numbers of survivors were counted and percentage of deaths were calculated. Larvae were considered dead if they did not exhibit any internal or external movement during several seconds of observation. This procedure was standardized testing a reference substance (Sodium Dodecyl Sulfate); some results are reported in this work. This article accompanies a video that describes the performance of procedural toxicity testing, showing all the steps related to the protocol.