Matteo Baini

Fin whales and microplastics: The Mediterranean Sea and the Sea of Cortez scenarios

The impact that microplastics have on baleen whales is a question that remains largely unexplored. This study examined the interaction between free-ranging fin whales (Balaenoptera physalus) and microplastics by comparing populations living in two semi-enclosed basins, the Mediterranean Sea and the Sea of Cortez (Gulf of California, Mexico). The results indicate that a considerable abundance of microplastics and plastic additives exists in the neustonic samples from Pelagos Sanctuary of the Mediterranean Sea, and that pelagic areas containing high densities of microplastics overlap with whale feeding grounds, suggesting that whales are exposed to microplastics during foraging; this was confirmed by the observation of a temporal increase in toxicological stress in whales. Given the abundance of microplastics in the Mediterranean environment, along with the high concentrations of Persistent Bioaccumulative and Toxic (PBT) chemicals, plastic additives and biomarker responses detected in the biopsies of Mediterranean whales as compared to those in whales inhabiting the Sea of Cortez, we believe that exposure to microplastics because of direct ingestion and consumption of contaminated prey poses a major threat to the health of fin whales in the Mediterranean Sea.

Presence of plastic debris in loggerhead turtle stranded along the Tuscany coasts of the Pelagos Sanctuary for Mediterranean Marine Mammals (Italy)

This work evaluated the presence and the frequency of occurrence of marine litter in the gastrointestinal tract of 31 Caretta caretta found stranded or accidentally bycaught in the North Tyrrhenian Sea. Marine debris were present in 71% of specimens and were subdivided in different categories according to Fulmar Protocol (OSPAR 2008). The main type of marine debris found was user plastic, with the main occurrence of sheetlike user plastic. The small juveniles showed a mean±SD of marine debris items of 19.00±23.84, while the adult specimens showed higher values of marine litter if compared with the juveniles (26.87±35.85). The occurrence of marine debris observed in this work confirms the high impact of marine debris in the Mediterranean Sea in respect to other seas and oceans, and highlights the importance of Caretta caretta as good indicator for marine litter in the Marine Strategy Framework Directive (MSFD) of European Union.

Plastic Debris Occurrence, Convergence Areas and Fin Whales Feeding Ground in the Mediterranean Marine Protected Area Pelagos Sanctuary: A Modeling Approach

The Mediterranean Sea is greatly affected by marine litter. In this area, research on the impact of plastic debris (including microplastics) on biota, particularly large filter-feeding species such as the fin whale (Balaenoptera physalus), is still in its infancy. We investigated the possible overlap between microplastic, mesoplastic and macrolitter accumulation areas and the fin whale feeding grounds in in a pelagic Specially Protected Area of Mediterranean Importance (SPAMI): the Pelagos Sanctuary. Models of ocean circulation and fin whale potential habitat were merged to compare marine litter accumulation with the presence of whales. Additionally, field data on microplastics, mesoplastics and macrolitter abundance and cetacean presence were simultaneously collected. The resulting data were compared, as a multi-layer, with the simulated distribution of plastic concentration and the whale habitat model. These data showed a high occurrence of microplastics (mean: 0.082 items/m2, STD ± 0.079 items/m2) spatial distribution agreed with our modelling results. Areas with high microplastic density significantly overlapped with areas of high macroplastic density. The most abundant polymer detected in all the sampling sites was polyethylene (PE), suggesting fragmentation of larger packaging items as the primary source. To our knowledge, this is the first study in the Pelagos Sanctuary in which the simulated microplastic distribution has been confirmed by field observations. The overlap between the fin whale feeding habitat and the microplastic hot spots is an important contribution for risk assessment of fin whale exposure to microplastics.

Occurrence, relative abundance and spatial distribution of microplastics and zooplankton NW of Sardinia in the Pelagos Sanctuary Protected Area, Mediterranean Sea

Environmental context Plastic materials are accumulating in the marine environment where they can now be found in the remotest areas of the worlds oceans. Microplastics (plastic particles ≤5mm), abundant in marine surface waters, are also found in neritic and pelagic waters of Mediterranean marine protected areas. Microplastics can accumulate along marine food chains, having noxious effects on marine organisms at different trophic levels and creating a serious threat to marine ecosystems. Abstract Floating plastic debris tends to fragment into smaller pieces, termed microplastics, which may increase the likelihood of ingestion of plastics by marine organisms entering the food web. This study analyses the amount and spatial distribution of microplastics and zooplankton in an area near Asinara National Park (NW Sardinia) and overlapping the Pelagos Sanctuary (Mediterranean Sea). Analysis showed microplastics in 81% of the 27 samples analysed, with a mean value of 0.17±0.32 items m–3. From geographic information system processing of the data, microplastics appeared more abundant (by a factor of four) in the pelagic than in the neritic environment, and showed a size range of the same order as major zooplanktonic taxa determined in the area. These findings suggest a potential risk of mesozooplankton and species preying on plankton mistaking microplastics for food. Further functional and toxicological studies are therefore necessary to assess the hazard associated with microplastics in the marine food web.

Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity

The Mediterranean Sea has been described as one of the most affected areas by marine litter in the world. Although effects on organisms from marine plastic litter ingestion have been investigated in several oceanic areas, there is still a lack of information from the Mediterranean Sea. The main objectives of this paper are to review current knowledge on the impact of marine litter on Mediterranean biodiversity, to define selection criteria for choosing marine organisms suitable for use as bioindicator species, and to propose a methodological approach to assessing the harm related to marine litter ingestion in several Mediterranean habitats and sub-regions. A new integrated monitoring tool that would provide the information necessary to design and implement future mitigation actions in the Mediterranean basin is proposed. According to bibliographic research and statistical analysis on current knowledge of marine litter ingestion, the area of the Mediterranean most studied, in terms of number of species and papers in the Mediterranean Sea is the western sub-area as well as demersal (32.9%) and pelagic (27.7%) amongst habitats. Applying ecological and biological criteria to the most threatened species obtained by statistical analysis, bioindicator species for different habitats and monitoring scale were selected. A threefold approach, simultaneously measuring the presence and effects of plastic, can provide the actual harm and sub-lethal effects to organisms caused by marine litter ingestion. The research revealed gaps in knowledge, and this paper suggests measures to close the gap. This and the selection of appropriate bioindicator species would represent a step forward for marine litter risk assessment, and the implementation of future actions and mitigation measures for specific Mediterranean areas, habitats and species affected by marine litter ingestion.

Pilot study on levels of chemical contaminants and porphyrins in Caretta caretta from the Mediterranean Sea

Perfluorinated compounds (PFCs), synthetic musks compounds (SMCs), bisphenol A (BPA), para-nonylphenol (p-NP) and polybrominated diphenyl ethers (PBDEs) are known for their toxicity and ability to interfere with the endocrine system. The aim of this study was to determine levels and distribution of the above mentioned compounds in liver samples of Caretta caretta and levels of porphyrins that have been proposed as sensitive biomarkers of exposure to contaminants. This paper reports the results for 9 specimens yet analysed. Musk ketone was never detected, PFOA was found in one sample, while PFOS was the prevalent contaminant. For PFCs the levels are lower than the results of studies of comparison. The porphyrins profile showed a predominance of protoporphyrins on coproporphyrins and uroporphyrins, with a positive statistical correlation between levels of PFOS and uroporphyrins. These data represent, for several parameters, the first evidence of contaminant levels and biomarker responses in loggerhead turtles.

Are whale sharks exposed to persistent organic pollutants and plastic pollution in the Gulf of California (Mexico)? First ecotoxicological investigation using skin biopsies

The whale shark (Rhincodon typus) is an endangered species that may be exposed to micro- and macro-plastic ingestion as a result of their filter-feeding activity, particularly on the sea surface. In this pilot project we perform the first ecotoxicological investigation on whale sharks sampled in the Gulf of California exploring the potential interaction of this species with plastic debris (macro-, micro-plastics and related sorbed contaminants). Due to the difficulty in obtaining stranded specimens of this endangered species, an indirect approach, by skin biopsies was used for the evaluation of the whale shark ecotoxicological status. The levels of organochlorine compounds (PCBs, DDTs), polybrominated diphenyl ethers (PBDEs) plastic additives, and related biomarkers responses (CYP1A) were investigated for the first time in the whale shark. Twelve whale shark skin biopsy samples were collected in January 2014 in La Paz Bay (BCS, Mexico) and a preliminary investigation on microplastic concentration and polymer composition was also carried out in seawater samples from the same area. The average abundance pattern for the target contaminants was PCBs>DDTs>PBDEs>HCB. Mean concentration values of 8.42ng/g w.w. were found for PCBs, 1.31ng/g w.w. for DDTs, 0.29ng/g w.w. for PBDEs and 0.19ng/g w.w. for HCB. CYP1A-like protein was detected, for the first time, in whale shark skin samples. First data on the average density of microplastics in the superficial zooplankton/microplastic samples showed values ranging from 0.00items/m3 to 0.14items/m3. A focused PCA analysis was performed to evaluate a possible correlation among the size of the whale sharks, contaminants and CYP1A reponses. Further ecotoxicological investigation on whale shark skin biopsies will be carried out for a worldwide ecotoxicological risk assessment of this endangerd species.

First detection of seven phthalate esters (PAEs) as plastic tracers in superficial neustonic/planktonic samples and cetacean blubber

Ingestion of plastics and microplastics by marine organisms may have physical and toxicological noxious effects creating a serious threat to marine species. There is a need to develop methods to evaluate the plastic exposure in free-ranging marine wildlife particularly related to microplastic ingestion. To this aim, seven phthalate esters (PAEs) were analysed, as plastic tracers, in neustonic/planktonic samples and skin biopsy samples of four cetacean species from the North-Western Mediterranean Sea. Among all phthalates, the highest frequency of detection was obtained from DEHP (78.9%), followed in descending order by MBzP (57.9%), MEHP and BBzP (both 52.6%), DIOIP (47.4%) and MBP and DNHP (both 42.1%). All 19 superficial tows analysed presented microplastic debris, confirming the widespread distribution of microplastics on the seawater surface in the Mediterranean Sea. The abundance of the smallest items (<0.5 mm) found in the samples was significantly correlated with MEHP, MBzP and BBzP, while the abundance of 0.5–1 mm and 2.5–5 mm items were related to BBzP and MBP, respectively. Regarding the PAEs, detected in the neustonic/planktonic samples correlated with microplastics (MEHP, MBzP, BBzP and MBP), appreciable levels of these compounds were found in all the four cetacean species. The present results represent a step forward in the application of a new non-invasive analytical method to evaluate PAEs as tracers of plastic exposure/ingestion in marine wildlife.

Abundance and characterization of microplastics in the coastal waters of Tuscany (Italy): The application of the MSFD monitoring protocol in the Mediterranean Sea

Monitoring efforts are required to understand the sources, distribution and abundance of microplastic pollution. To verify the abundance of microplastics along the Tuscan coastal waters (Italy), water-column and surface samples were collected in two seasons across four transects at different distances to the coast (0.5, 5, 10 and 20 km), within the implementation of the European Marine Strategy Framework Directive. The results show an average concentration of 0.26 items/m3 in the water-column samples and 41.1 g/km2 and 69,161.3 items/km2 of floating microplastics, with an increase with the distance to the coast The seasonality and the sampling area do not affect the abundance of microplastics. The most abundant size class is 1-2.5 mm as fragments and sheets suggesting that fragmentation of larger polyethylene and polypropylene items could be the main source of microplastics. These data represent the application of a harmonized protocol to make the data on microplastics comparable and reliable.

Impacts of Marine Litter on Cetaceans

Abstract Marine litter has become a pervasive pollution problem affecting all of the worlds seas. It is widely documented that marine litter, in particular plastic, has negative impacts on marine wildlife, primarily due to ingestion and entanglement. Since most cetacean species (more than 66%) are adversely affected by this pollution, this chapter is devoted to defining the impact of marine plastic pollution on cetaceans, including current knowledge, methodologic advances, and new data available on this emerging issue. The final objective of this chapter is also to identify key knowledge gaps and establish priority research and mitigation recommendations.