The exponential production and use of plastics has generated increasing environmental release over the past decades, and microplastics (MPs) have been reported across all the oceans. Field studies have documented the occurrence of MPs in several species, but important knowledge gaps still remain. In the present study, we characterized the distribution of MPs in ten sediment-dwelling and epibenthic species representative of different habitat, feeding modes and trophic levels within the inner Oslofjord (Oslo, Norway), an area subjected to moderate anthropogenic pressures. Analysed species included fish, bivalves, echinoderms, crustaceans and polychaetes. MPs were present in all the species with a frequency up to 65% of positive individuals for some species. In most cases, 1 or 2 MPs were found per individual, but some organisms contained up to 7 particles. A total of 8 polymer typologies were identified, with PE and PP being the most common according to our extraction protocol. MP sizes ranged from 41 μm to lines as long as 9 mm. Our results indicate that occurrence of MPs in analysed biota is not influenced by organism habitat or trophic level, while characteristics and typology of polymers might be significantly affected by feeding mode of organisms.

In this work, three gastropods Patella vulgata, Osilinus turbinata, and Tahis clavigera, one echinoderm Parancetrotus lividus, one coelenterate Anemonia sulcata, and two seaweed Padina pavonica, and Cystoseira mediterranea were collected from three different marine areas of Sardinia in the Mediterranean sea and studied for heavy metals and metalloid content and accumulation trends.Inductively coupled plasma optical emission spectrometry (ICP-OES) was used for the determination of Al, AS, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Sn, Sr, Te, Ti, V and Zn in the selected samples. The results showed that gastropods were capable of accumulating Al, Ba, Cu, Fe, Sr, and Zn; seaweeds can better concentrate Al, Fe, and Zn than all other species. At the same time, echinoderms and coelenterate had limited ability to store specific metals, showing a much more homogeneous distribution. PCA analysis allowed us to discriminate among the sites and the species. Cala Zafferano was the area with the higher values of accumulation of all metals in all species as expected, considering its proximity to industrial sites. The results of the analysis showed clearly that heavy metal and metalloid accumulation was different for each species studied. Therefore, for a correct environmental assessment of a given area, a comprehensive approach is strongly recommended by exploiting the different properties of both accumulation and concentration of the metals by different aquatic species.

The wide ecological relevance of lipid homeostasis modulators in the environment has been increasingly acknowledged. Tributyltin (TBT), for instance, was shown to cause lipid modulation, not only in mammals, but also in fish, molluscs, arthropods and rotifers. In vertebrates, TBT is known to interact with a nuclear receptor heterodimer module, formed by the retinoid X receptor (RXR) and the peroxisome proliferator-activated receptor (PPAR). These modulate the expression of genes involved in lipid homeostasis. In the present work, we isolated for the first time the complete coding region of the Echinodermata (Paracentrotus lividus) gene orthologues of PPAR and RXR and evaluated the ability of a model lipid homeostasis modulator, TBT, to interfere with the lipid metabolism in this species. Our results demonstrate that TBT alters the gonadal fatty acid composition and gene expression patterns: yielding sex-specific responses in fatty acid levels, including the decrease of eicosapentaenoic acid (C20:5 n-3, EPA) in males, and increase of arachidonic acid (20:4n-6, ARA) in females, and upregulation of long-chain acyl-CoA synthetase (acsl), ppar and rxr. Furthermore, an in vitro test using COS-1 cells as host and chimeric receptors with the ligand binding domain (LBD) of P. lividus PPAR and RXR shows that organotins (TBT and TPT (Triphenyltin)) suppressed activity of the heterodimer PPAR/RXR in a concentration-dependent manner. Together, these results suggest that TBT acts as a lipid homeostasis modulator at environmentally relevant concentrations in Echinodermata and highlight a possible conserved mode of action via the PPAR/RXR heterodimer.

Probabilistic environmental quality criteria for Naphthalene (Nap), Phenanthrene (Phe), Fluoranthene (Flu), Pyrene (Pyr), Triclosan (TCS), Tributyltin (TBT), Chlorpyrifos (CPY), Diuron (DUR), γ-Hexaclorocyclohexane (γ-HCH), Bisphenol A (BPA) and 4-Nonylphenol (4-NP) were derived from acute toxicity data using saltwater species representative of marine ecosystems, including algae, mollusks, crustaceans, echinoderms and chordates. Preferably, data concerns sublethal endpoints and early life stages from bioassays conducted in our laboratory, but the data set was completed with a broad literature survey. The Water Quality Criteria (WQC) obtained for TBT (7.1·10⁻³ μg L⁻¹) and CPY (6.6· 10⁻³ μg L⁻¹) were orders of magnitude lower than those obtained for PAHs (ranging from 3.75 to 45.2 μg L⁻¹), BPA (27.7 μg L⁻¹), TCS (8.66 μg L⁻¹) and 4-NP (1.52 μg L⁻¹). Critical values for DUR and HCH were 0.1 and 0.057 μg L⁻¹ respectively. Within this context, non-selective toxicants could be quantitatively defined as those showing a maximum variability in toxicity thresholds (TT) of 3 orders of magnitude across the whole range of marine diversity, and a cumulative distribution of the TT fitting to a single log-logistic curve, while for selective toxicants variability was consistently found to span 5 orders of magnitude and the TT distribution showed a bimodal pattern. For the latter, protective WQC must be derived taking into account the SSD of the sensitive taxa only.

Plastic debris provides long-lasting substrates for benthic organisms, thus acting as a potential vector for their dispersion. Its interaction with these colonizers is, however, still poorly known. This study examines fouling communities on beached, buoyant and benthic plastic debris in the Catalan Sea (NW Mediterranean), and characterizes the plastic type. We found 14 specimens belonging to two phyla (Annelida and Foraminifera) on microplastics, and more than 400 specimens belonging to 26 species in 10 phyla (Annelida, Arthropoda, Brachiopoda, Bryozoa, Chordata, Cnidaria, Echinodermata, Mollusca, Porifera and Sipuncula) on macroplastics. With 15 species, bryozoans are the most diverse group on plastics. We also report 17 egg cases of the catshark Scyliorhinus sp., and highlight the implications for their dispersal. Our results suggest that plastic polymers may be relevant for distinct fouling communities, likely due to their chemical structure and/or surface properties. Our study provides evidence that biofouling may play a role in the sinking of plastic debris, as the most abundant fouled plastics had lower densities than seawater, and all bryozoan species were characteristic of shallower depths than those sampled. More studies at low taxonomic level are needed in order to detect new species introduction and potential invasive species associated with plastic debris.

The Gulf contains important biodiversity, but is also heavily impacted. While studies have measured seawater contaminants and toxicity, we are not aware of discrete sampling of the sea surface microlayer (SML). This ocean-atmosphere interface is important environmentally, but also sensitive to marine and atmospheric contaminant inputs. We sampled the SML and subsurface seawater (SSW) from the Gulf in August 1991 and 1992. The SML exhibited significant enrichment of petroleum hydrocarbons, Cu, Cd and Pb, which persisted more than one year after the massive 1991 Gulf War oil spill. Toxicity to echinoderm larvae was also greater in the SML. This likely reflects effects of contaminants measured and other stressors. Sophisticated techniques used over recent decades to determine biological effects of contaminants in the Gulf could usefully extend to the SML. Our study has demonstrated its sensitivity and could serve as a ‘baseline’ for determining long-term persistence of seawater contamination and toxicity.

Substrate cover, water quality parameters and assemblages of corals, fishes, sponges, echinoderms, ascidians, molluscs, benthic foraminifera and macroalgae were sampled across a pronounced environmental gradient in the Jakarta Bay–Thousand Islands reef complex. Inshore sites mainly consisted of sand, rubble and turf algae with elevated temperature, dissolved oxygen, pH and chlorophyll concentrations and depauperate assemblages of all taxa. Live coral cover was very low inshore and mainly consisted of sparse massive coral heads and a few encrusting species. Faunal assemblages were more speciose and compositionally distinct mid- and offshore compared to inshore. There were, however, small-scale differences among taxa. Certain midshore sites, for example, housed assemblages resembling those typical of the inshore environment but this differed depending on the taxon. Substrate, water quality and spatial variables together explained from 31% (molluscs) to 72% (foraminifera) of the variation in composition. In general, satellite-derived parameters outperformed locally measured parameters.

The largest municipal outfall on the west coast of Canada discharges into the southeastern Strait of Georgia, where high sedimentation from the Fraser River has maintained stable sediment geochemical and contaminant conditions from 2001 to 2011. Outfall exposure has not affected trophic structure or diversity (H′), but has significantly affected faunal composition and species richness, resulting in loss of crustaceans and echinoderms near-field. Organic biomass and production have mostly remained within expected background ranges for the Strait, due to recent increases in a low oxygen tolerant polychaete in the high deposition zone. A significant regional shift in faunal composition occurred after 2003, followed by gradual declines in richness, abundance, calcareous organisms and production. This cannot be attributed to changes in outfall exposure, but is exaggerated by it. We hypothesize that changing river flow, extreme events and shifts in offshore upwelling water temperature, oxygen and pH may be increasing geochemical stress in benthos.

Distribution of five heavy metals (Cd, Cr, Cu, Pb, and Zn) in molluscan and echinoderm species collected from Kerala and Gulf of Mannar in Southern India is presented. Atomic absorption spectrometry was used to determine metal concentrations. Concentrations of metals showed a descending order of Zn > Cu > Pb > Cd > Cr. Zn and Cu might have originated from both natural and man-made sources. However, Cd, Cr, and Pb could have strong anthropogenic influences such as harbour activities and untreated industrial and agricultural runoff. Bioaccumulation factor (BAF) value of Cd in two edible bivalves from Munambam is slightly greater than one. Regular consumption of Cd-loaded shellfish can cause serious health hazards and concerns to humans. BAF results showed that Zn, Cu, Pb, and Cd were more bioaccumulated and beyond the threshold limits in certain species. It is evident that consumption of shellfish from the Kerala coastal waters may have adverse health impacts to the consumers.

To understand the current community structure and diversity of macrobenthos in Jiaozhou Bay, a survey was conducted at eight sampling stations in April, July, and October 2018, as well as January 2019. Eighty-two macrobenthos species were collected, including 30 of Annelida, 21 of Mollusca, 20 of Crustacea, 8 of Echinodermata, and 3 classified as “Others”. Ruditapes philippinarum was a common dominant species in summer, autumn, and winter. The annual average abundance and biomass were 280 ind./m² and 446.45 g/m², respectively. Shannon-Wiener diversity varied from 0.09 to 2.45 with an average value of 1.14. Margalef richness was 0.17–2.32 with an average value of 0.89. Pielou evenness was 0.14–1.00 with an average value of 0.71. The seasonal variation patterns of all tested indices were largely the same, with the highest in spring, next highest in winter, and lower in summer and autumn. The diversity at different survey stations varies greatly.