From inshore to offshore: distribution of microplastics in three Italian seawaters.

A comprehensive understanding of the concentration of microplastics (MPs) in seawaters is essential to implement monitoring programs and understand the impacts on ecosystems, as required by the European legislation to protect the marine environment. In this context, the purpose of this study is to investigate the composition, quantity, and spatial distribution of microplastics from coastal to offshore areas in three Italian seawaters. In addition, the distribution of microplastics between surface and subsurface water layers was analyzed in order to better understand the dynamics of MPs in the upper layers of the water column. A total number of 6069 MPs (mean total concentration of 0.029 microplastics · m-2) were found to be heterogeneous in type, shape, and color. In general, MPs concentrations decrease with coastal distance, except when environmental forcings are predominant (such as sea currents). Moreover, the amount of surface MPs was almost four times that of subsurface microplastics, which consisted mostly of fibers. In light of these results, it becomes clear how critical it is to plan remediation actions and programs to minimize microplastic accumulations in the sea.

Polymer composition assessment suggests prevalence of single-use plastics among items ingested by loggerhead sea turtles in the western mediterranean sub-region.

The ingestion of plastic is becoming a major concern for various species and particularly for marine turtles across the globe. The loggerhead sea turtle (Caretta caretta) was recently chosen by the European Commission as a bio-indicator for plastic pollution within the Mediterranean basin. We further investigated which items this key species is more prone to ingest, following the standardised Marine Strategy Framework Directive protocols. Moreover, we integrated to this protocol the Fourier Transform Infrared Spectroscopy, which allowed us to determine the polymer type of each item. We analysed samples from 226 sea turtles from 2008 to 2017 in two areas of the western Mediterranean sub-region (sensu MSFD). In the Lazio area we found a frequency of occurrence of plastic ingestion of 78.33%, while in Sardinia 41.79%. The analysis of the litter categories, among all individuals, highlights a prevalence of user-sheet (Use-She; 69.13%) and user-fragment plastics (Use-Fra; 20.84%). In addition, the polymer analysis showed a dominance of polyethylene (65.98%) and polypropylene (26.23%). As a result, by looking at other works that have investigated polymer types and items sources, we are able to infer that 77.25% of the objects ingested by the C. caretta individuals are attributable to disposable daily-life objects managed in an improper way. Therefore, C. caretta apart from being an efficient bio-indicator for plastic pollution, highlighting spatial and temporal concentration differences, it could also be used to verify the effectiveness of the Single-use Plastic Directive (EU 2019/904).

Field evidence for microplastic interactions in marine benthic invertebrates.

Microplastics represent an important issue of concern for marine ecosystems worldwide, and closed seas, such as the Mediterranean, are among the most affected by this increasing threat. These pollutants accumulate in large quantities in benthic environments causing detrimental effects on diverse biocenoses. The main focus of this study is on the 'polychaetes-microplastics' interactions, particularly on two species of benthic polychaetes with different ecology and feeding strategies: the sessile and filter feeder Sabella spallanzanii (Gmelin, 1791) and the vagile carnivorous Hermodice carunculata (Pallas, 1766). Since not standardized protocols are proposed in literature to date, we compared efficiencies of diverse common procedures suitable for digesting organic matter of polychaetes. After the definition of an efficient digestion protocol for microplastics extraction for both polychaetes, our results showed high microplastics ingestion in both species. Microplastics were found in 42% of individuals of S. spallanzanii, with a mean of 1 (± 1.62) microplastics per individual, in almost all individuals of H. carunculata (93%), with a mean of 3.35 (± 2.60). These significant differences emerged between S. spallanzanii and H. carunculata, is probably due to the diverse feeding strategies. The susceptibility to this pollutant makes these species good bioindicators of the impact of microplastics on biota.

Spatial variability and influence of biological parameters on microplastic ingestion by Boops boops (L.) along the Italian coasts (Western Mediterranean Sea).

Recently, many studies focus on the ingestion of microplastics by marine biota. Fish exploit almost every kind of marine environment, occupy many ecological niches and are an important food source for human populations worldwide. For these reasons, they seem to represent very appropriate biological indicators of microplastic ingestion. UNEP/MAP SPA/RAC (2018) identified the bogue, Boops boops (Linnaeus, 1758), as a possible target species for monitoring microplastic ingestion in fish populations. This study provides the first report of microplastic ingestion by B. boops from the Tyrrhenian and the Ligurian Seas (Western Mediterranean Sea). Generalized Linear Mixed Models were used to analyse the relationship among biological parameters and environmental factors. A total of 379 bogues were collected in three Italian regions, subject to different anthropogenic pressures (river input, human population, shipping lanes and distance from the coast). Microplastics were detected in the gastrointestinal tract of most individuals (56%) with a mean of 1.8 (±0.2) microplastics per individual. Our study further confirms that this species is able to highlight differences in the ingestion of microplastics according to local anthropization, resulting Latium region to be the most polluted. Fish with lower physical condition are more likely to ingest microplastics, suggesting a relationship with the level of local environmental contamination. Finally, the ingestion of microplastics might be influenced by behavioural differences between sexes. According to our results, males ingest significantly more microplastics than females (p < 0.05). Our research confirms that an extensive knowledge on the biology of a bioindicator species is a priority for developing a valid monitoring strategy, such as the Marine Strategy Framework Directive for European waters.

Food preference determines the best suitable digestion protocol for analysing microplastic ingestion by fish.

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.

Exploring microplastic ingestion by three deep-water elasmobranch species: A case study from the Tyrrhenian Sea.

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.

Marsupialization and sclerotherapy with povidone iodine and ethanol of a branchial remnant cyst in an Arabian filly.

Branchial remnant cysts are an uncommon cause of masses of the throatlatch area in horses. Two methods of treatment have been proposed in literature, both with complications. This manuscript proposes a method (marsupialization and sclerotherapy) for the treatment of a cyst in a 1.5-year-old Arabian filly. Diagnosis was made by ultrasonographic, radiographic and endoscopic examinations, revealing an anechoic fluid-filled structure and a well-defined capsule not in communication with other structures. After emptying the cyst, the skin was sutured circumferentially to the cyst wall; it was then flushed first with a solution of ethanol and povidone-iodine, then with sterile saline. Eight months after surgery, the filly had no recurrence of the cyst and the stoma was healed.

Benthic foraminifera from the coastal zone of Baia (Naples, Italy): assemblage distribution and modification as tools for environmental characterisation.

The coastal zone of Baia (Naples) is currently included in a protected marine area, but in past it was affected by strong anthropogenic pressure for commercial harbour activity. In order to investigate the impact of past activities, a multidisciplinary characterisation was undertaken to evaluate the environmental quality of marine sediments. Thirty-six grab samples were collected for grain-size, heavy metals, PAHs and PCBs analyses. Rose Bengal stained replicates were taken for the analysis of benthic foraminifera. Chemical analyses highlighted sediment pollution mainly due to Cu, Hg, Pb, Zn, PAHs and PCBs in the northern and southern part of the study area, where some sunken vessels had been present for many decades. Modifications of foraminiferal diversity and density, and increased percentage of abnormal specimens, were considered as indicators of environmental degradation. Correlation between faunal parameters and pollutant concentrations was found by means of statistical analysis. The highest degree of environmental stress shown by foraminifera in the northern sector could be referable to the high concentrations of PCBs (up to 144 ng g(-1) d.w.).

Methylmercury determination in marine sediment and organisms by Direct Mercury Analyser.

An analytical method for simple and rapid determination of methylmercury in sediment and organism samples is described. The proposed method employs the oxygen combustion-gold amalgamation using Direct Mercury Analyser (DMA-80) after complete removal of MeHg by organic extraction and back extraction to an aqueous medium. DMA-80 instrument is equally suitable for the analysis of solid and liquid materials and has a good detection limit. The analytical performance of this method was evaluated by analysis of certified reference materials (CRM-580, IAEA-405, DORM-2, DOLT-3, SRM-2976 and SRM-2977) assessing its quality in terms of accuracy, repeatability and quantification limit. Furthermore total mercury and methylmercury have been analysed in sediment and organism samples collected during the XXI Italian Antarctic Expedition in Terra Nova Bay (Ross Sea, Northern Victoria Land). The results obtained show the validity of the proposed method as ready-to-use analytical method to analyse real samples.