T. Campani

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.

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.

Impact of Raw and Bioaugmented Olive-Mill Wastewater and Olive-Mill Solid Waste on the Content of Photosynthetic Molecules in Tobacco Plants

Disposal and reuse of olive-mill wastes are both an economic and environmental problem, especially in countries where the cultivation of olive trees is extensive. Microorganism-based bioaugmentation can be used to reduce the pollutant capacity of wastes. In this work, bioaugmentation was used to reduce the polyphenolic content of both liquid and solid wastes. After processing, bioaugmented wastes were tested on the root development of maize seeds and on photosynthesis-related molecules of tobacco plants. In maize, we found that bioaugmentation made olive-mill wastes harmless for seed germination. In tobacco, we analyzed the content of RuBisCO (ribulose-1,5-bisphosphate carboxylase oxygenase) and of the photosynthetic pigments lutein, chlorophylls, and β-carotene. Levels of RuBisCO were negatively affected by untreated wastewater but increased if plants were treated with bioaugmented wastewater. On the contrary, levels of RuBisCO increased in the case of plants treated with raw olive-mill solid waste. Pigment levels showed dissimilar behavior because their concentration increased if plants were irrigated with raw wastewater or treated with raw olive-mill solid waste. Treatment with bioaugmented wastes restored pigment content. Findings show that untreated wastes are potentially toxic at the commencement of treatment, but plants can eventually adapt after an initial stress period. Bioaugmented wastes do not induce immediate damages, and plants rapidly recover optimal levels of photosynthetic molecules.

First ecotoxicological assessment of Caretta caretta (Linnaeus, 1758) in the Mediterranean Sea using an integrated nondestructive protocol

The loggerhead sea turtle (Caretta caretta) is a long-lived carnivorous reptile included in the IUCN Red List. The IUCN assessment for this species underlines the lack of information regarding pollution and pathogens and indicates as a priority effort to investigate and reduce the impacts of these threats. In this contest, the aim of our study was to conduct the first ecotoxicological assessment of this species in the Mediterranean Sea using a nondestructive integrated methodology. We set up and applied a monitoring protocol which includes endpoints, such as CYP1A, LPO, ENA assay, B esterases, never investigated before in this species. Seventy-five loggerhead turtles were sampled in a nondestructive way in Italian Sea Turtle Rescue Centers or free-ranging along the Spanish coasts. Blood, skin and carapace samples were used to test biomarker responses (CYP1A, VTG, LPO, Comet and ENA assay, BChE, GGT) and contaminant (OCs, PAHs, Pb, Cd, Hg) levels. Elaboration of experimental results was carried out taking also into consideration different age classes of the specimens. Among the main results obtained we should underline the statistically significant correlation between carcinogenic PAHs in blood and DNA fragmentation as well as between Cd in carapace and GGT in plasma. We also evidenced as youngest animals showed significantly higher DNA fragmentations, BChE inhibition and increase of GGT. Older specimens showed the highest levels of erythrocyte nuclear abnormalities which may indicate a long term toxicological stress. This study contributed to expand the knowledge about the ecotoxicology of C. caretta in the Mediterranean. The nondestructive protocol could also be applied to other marine ecosystems and other sea turtle species.