The anthropogenic marine debris, especially abandoned, lost or otherwise discarded Fishing Gear (ALDFG), represents a rising concern, because of its potential harmful impact on the marine animal forests. We carried out 13 km of video recordings, by means of a remotely operated vehicle, from 10 to 210 m depth, in an anthropised area of the Tyrrhenian Sea (Mediterranean Sea). This site, for its high ecological importance and biodiversity value, has been identified for the establishment of a new marine protected area (MPA). The aim of this paper was to assess marine litter abundance and its effects on the benthic fauna. The debris density, in the study area, ranged from 0.24 to 8.01 items/100 m2, with an average of 3.49 (±0.59) items/100 m2. The derelict fishing gear, mainly fishing lines, were the main source of marine debris, contributing 77.9% to the overall litter. The impacts of debris on the benthic fauna were frequently recorded, with 28.5% of the litter entangling corals and impacting habitats of conservation concern. These impacts were exclusively caused by the derelict fishing gear (91.2% by longlines), and the highest percentage (49.1%) of ALDFG causing impacts was observed from 41 to 80 m depth, in the coralligenous biocenosis. The results of the present study will help the fulfilment of “harm” monitoring, as recommended by the Marine Strategy Framework Directive (MSFD) and the UN Environment/MAP Regional Plan on the marine litter management in the Mediterranean Sea. Regarding the actions to reduce the derelict fishing gear, preventive measures are usually preferred instead of the extensive removals based on cost-effectiveness and sustainability. The establishment of a new MPA in the area could be a good solution to reduce ALDFG, resulting in the improvement of the ecological status of this coastal area.

This study analyzes microplastic ingestion by three deep-water elasmobranch species (Galeus melastomus, Scyliorhinus canicula and Etmopterus spinax) from the Tyrrhenian Sea, discriminating between stomach and intestine contents. The absence of significant differences in frequency and abundance of plastic items into stomachs seems to suggest that ecological diversity among the three sharks does not strongly influence the probability of plastic ingestion in the study area. On the other hand, the detected differences in the microplastic content into the intestine might be due to a different retention time of microplastics, suggesting how feeding habits could influence metabolic features, and therefore affect the recovery of ingested plastic items. This information would improve the future development of marine micro-litter monitoring systems, following the MSFD requirements. Moreover, this study shows that all the three examined elasmobranch species can give important information even with relatively small sample sizes (N ≈ 30), and they could be used as target species for monitoring micro-litter ingestion in deep-water habitats.

Seafloor pollution by benthic litter is an emerging phenomenon, although debris colonization by biota remains largely unexplored. We characterized the litter of the continental slope (~400–600 m) of the Gulf of Naples (Mediterranean) and investigated its fouling biota through integrative taxonomic approaches. Plastic pieces (82 %) with land-based origin (96 %) and limited sizes (10–20 cm) were the items most commonly encountered, suggesting a transfer to deep waters through floating and sinking. The majority of the items were not fouled, and the debris hosted an impoverished biota, leading to hypothesize that benthic litter supports wide communities only in shallow waters. Higher colonization rates were observed for gastropod and cephalopod eggs with no preference for materials and sizes, suggesting that even small pieces of soft plastic provide a spawning habitat for molluscs and affect species' connectivity in the deep-sea ecosystem. Holistic approaches are necessary to evaluate interactions between litter and biota.

Geographical and temporal differences of microplastic occurrence were documented in water and fish collected in 2017 and 2019 from the Giglio Island (North Tyrrhenian Sea) close to the area where the Costa Concordia sank in January 2012. Results on water samples showed a site-dependent difference, suggesting the role of surface current dynamics in the microplastic local distribution, while tested Neuston nets (200 μm and 330 μm mesh size) did not influence microplastic retention efficiency. Fish exhibited in 2019 a higher frequency of specimens positive to microplastic ingestion with respect to 2017, with an occurrence higher than those typically observed in other Mediterranean areas. Both in water and fish, fragments were the dominating shape, polypropylene and polyethylene were the prevalent polymers, without particular difference between sites and years. This study highlights the importance of applying microplastic investigation in biotic and abiotic matrices for an effective monitoring of this pollution in the marine environment.

Fouling communities were studied in three port systems of Northern Tyrrhenian Sea (Western Mediterranean), focusing on the occurrence of non-indigenous species (NIS). For each port system two harbour types (large port and recreational marina) were sampled and, within each large port, fouling samples were collected considering two use destinations (commercial and touristic harbour). Among the 431 taxa identified, forty-two were alien or cryptogenic, four of which were new records for the study area. Harbour type and use destination shaped fouling communities and NIS assemblages, with their relative influence varying among different port systems. High fouling variability was detected within port environments and between different marinas. NIS showed the highest occurrence in large ports, in which the touristic harbour generally hosted the greatest amount. Therefore, the touristic harbours within large ports were identified as susceptible areas for NIS establishment and their possible subsequent spread at local scale through recreational maritime traffic.

Few studies focused on behaviour adaptations of organisms to marine litter (ML) pollution in Mediterranean Sea. This research, investigates on some behavior traits of Octopus vulgaris, focusing on the interaction with ML during the artisanal fishing activities by the bottom traps in a small coastal area of the southern Tyrrhenian Sea. For the first time, this pilot study uses an integrated approach based on the Fishermen Ecological Knowledge as well as the analysis of ML found in the traps. First assessment of plastic ingestion in this species are also reported. Plastic and metal were the predominant ML categories observed into the bottom traps. A total of 62 plastics, mainly small microplastics and fibres shaped, were ingested. The ML finding in the bottom traps suggests an interesting behavior of the common octopus regarding its interaction with ML, in fact, it seems to bring ML inside its dens, as a collector.

Anthropogenic litter negatively impacts the marine environment and threatens biodiversity. At the same time, it represents a suitable substrate for the settlement of sessile species, thus potentially altering composition and structure of soft bottom benthic assemblages. By using a Remotely Operated Vehicle (ROV), we hereby investigated patterns of abundance, distribution, and origin of benthic litter in three subtidal habitats of a heavily urbanized area and tested whether litter distribution related to patterns of fish and mega- and macro-benthic diversity. Litter accumulation mostly occurred on soft bottoms, while rocky substrata were the least affected, albeit being particularly threatened by sea-based pollution. As expected, the highest biodiversity was observed on rocky bottoms, hosting notable biogenic formations (Cladocora caespitosa, Leptogorgia sarmentosa) despite the area is historically affected by anthropogenic activities. No correlation was found between biota and marine litter, suggesting that litter does not apparently influence biodiversity and distribution of the investigated assemblages.

Microplastic presence in the marine environment has generated considerable concern. Many procedures for microplastics detection in fish gastrointestinal tract have been recently developed. In this study, we compared efficiencies of two common procedures applied for the digestion of organic matter (10% KOH; 15% H₂O₂) with a new proposal (mixture of 5% HNO₃ and 15% H₂O₂). We considered ecological diversity among species and differences in their diet compositions as factors that could affect the efficiency and feasibility of analytical approaches. Our aim was to understand whether either one of the three protocols might be suitable for all species or it might be more advisable to select a method according to the gut content determined by different food preferences. The results showed that the trophic level and feeding habits should be considered for protocol selection. Finally, we applied the best protocols on samples from the Tyrrhenian sea.

As the production of plastic products continues to increase, determining the fate of plastic waste in the environment is of high importance. Densely populated areas, such as Mediterranean coastlines, represent locations of high pollution risk for surrounding environments. Thus, this study aims to assess the abundance, size, and composition of floating meso- and microplastics collected during four weeks in 2018 in the Ligurian and Tyrrhenian Seas. The results show average meso- and microplastic particle concentrations of 28,376 ± 28,917 particles km⁻², and an average mass of 268.61 ± 421.18 g km⁻². The particle shape ratio was 65% fragments, 19% films, 10% lines, 4% foams, and 2% pellets. Microplastic particles comprised 65% of the sample. Analysis with attenuated total reflection Fourier transform infrared spectroscopy showed predominant polymer types included polyethylene, polypropylene, polystyrene, and polyamide. These data are an important starting point for long-term monitoring of plastic pollution levels within this region.

The Gulf of Follonica (Italy) is impacted by the chemical pollution from ancient mining activity and present industrial processes. This study was aimed to determine the bioavailability of dioxin-like compounds (DLCs) in coastal marine environment and to assess the genotoxic potential of waste waters entering the sea from an industrial canal. Moderately high levels of DCLs compounds (∑PCDDs+PCDFs 2.18–29.00pg/g dry wt) were detected in Mytilus galloprovincialis transplanted near the waste waters canal and their corresponding Toxic Equivalents (TEQs) calculated. In situ exposed mussels did not show any genotoxic effect (by Comet and Micronucleus assay). Otherwise, laboratory exposure to canal waters exhibited a reduced genomic template stability (by RAPD-PCR assay) but not DNA or chromosomal damage. Our data reveal the need to focus on the levels and distribution of DLCs in edible species from the study area considering their potential transfer to humans through the consumption of sea food.