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Microplastics pollution along the central Atlantic coastline of Morocco Full text
2022
Abelouah, Mohamed Rida | Ben-Haddad, Mohamed | Rangel-Buitrago, Nelson | Hajji, Sara | El Alem, Noureddine | Ait Alla, Aicha
This baseline study describes the microplastic (MPs) problem on seven beaches located on Agadir, central Atlantic coast of Morocco. Microplastics abundances (densities) ranged from 7680 MPs/kg to 34,200 MPs/kg above other world beaches. The following shapes were found: fibers, fragments, films, and pellets. Fibers were the dominant typology with a 73%. Polyethylene (PE) was the predominant polymer in all beaches with an average percentage of 59%, followed by Polypropylene (PP - 18%), Polystyrene (PS - 9%), Polyvinyl chloride (PVC - 8%), and Ethylene-vinyl acetate (EVA - 6%). Microplastics abundances presented in this work suggest continuous inputs of plastics of all sizes and types. Also, all observed shapes highlight a combination of sources (primary and secondary). Central Atlantic Moroccan beaches are currently affected by extreme values of MPs that demand urgent interventions to restore environmental quality.
Show more [+] Less [-]The emergence of nanotechnology in mitigating petroleum oil spills Full text
2022
Mishra, Saurabh | Chauhan, Geetanjali | Verma, Samarpit | Singh, Ujjawal
The world has witnessed the circumstances shaped by the oil spill for many decades that cause serious environmental problems and adverse effects on human health. Many techniques and remediation methods are followed for efficient oil spill cleanups but with the limitations and environmental issues, these procedures were not completely efficient. The “nanotechnology” word itself has fascinated not only the researchers but also many industries and the global race is on to tap its potential and to derive benefit from it. Their small size and exceptional properties have proven their potential in providing technological solutions to engineering problems. This study focuses on the scope of nanotechnology in oil spill cleanups and shows how the limitations presented by conventional methodologies can be overcome. This paper categorizes and thoroughly reviews the application of nanotechnology in oil spill cleanups in different forms and also focuses on the environmental aspects of it.
Show more [+] Less [-]Characterization of foamed plastic litter on Danish reference beaches – Pollution assessment and multivariate exploratory analysis Full text
2022
Feld, Louise | da Silva, Vitor Hugo | Strand, Jakob
Foamed litter comprise a significant amount of the pollution at beaches globally. This group represents a variety of foamed items and fragments originating from different applications and sources. Although foamed plastic contributes importantly to the marine environmental pollution, there is generally limited knowledge of the composition of this litter pool. The aim of this study was to characterize item types and polymer materials of foamed litter from six Danish reference beaches during the period 2018–2021. The foamed litter were classified into ten categories, including identifiable items, as well as fragments of foamed PS, or pieces of other foamed polymers of rigid or flexible sponges. Foamed PS (42%) and PUR (49%) were identified as the dominant polymers by FTIR analysis. Multivariate exploratory analysis was performed to investigate PUR foam, and specific spectra features for rigid and flexible foam were demonstrated. Furthermore, we assessed different correlation methods for identification of PUR foams.
Show more [+] Less [-]Mercury stable isotopes suggest reduced foraging depth in oxygen minimum zones for blue sharks Full text
2022
Le Croizier, Gaël | Sonke, Jeroen E. | Lorrain, Anne | Serre, Sandrine | Besnard, Lucien | Schaal, Gauthier | Amezcua-Martinez, Felipe | Point, David
Mercury stable isotopes suggest reduced foraging depth in oxygen minimum zones for blue sharks Full text
2022
Le Croizier, Gaël | Sonke, Jeroen E. | Lorrain, Anne | Serre, Sandrine | Besnard, Lucien | Schaal, Gauthier | Amezcua-Martinez, Felipe | Point, David
Oxygen minimum zones (OMZs) are currently expanding across the global ocean due to climate change, leading to a compression of usable habitat for several marine species. Mercury stable isotope compositions provide a spatially and temporally integrated view of marine predator foraging habitat and its variability with environmental conditions. Here, we analyzed mercury isotopes in blue sharks Prionace glauca from normoxic waters in the northeastern Atlantic and from the world's largest and shallowest OMZ, located in the northeastern Pacific (NEP). Blue sharks from the NEP OMZ area showed higher Δ¹⁹⁹Hg values compared to sharks from the northeastern Atlantic, indicating a reduction in foraging depth of approximately 200 m. Our study suggests for the first time that blue shark feeding depth is altered by expanding OMZs and illustrates the use of mercury isotopes to assess the impacts of ocean deoxygenation on the vertical foraging habitat of pelagic predators.
Show more [+] Less [-]Mercury stable isotopes suggest reduced foraging depth in oxygen minimum zones for blue sharks Full text
2022
Le Croizier, Gaël | Sonke, Jeroen E. | Lorrain, Anne | Serre, Sandrine | Besnard, Lucien | Schaal, Gauthier | Amezcua-martinez, Felipe | Point, David
Oxygen minimum zones (OMZs) are currently expanding across the global ocean due to climate change, leading to a compression of usable habitat for several marine species. Mercury stable isotope compositions provide a spatially and temporally integrated view of marine predator foraging habitat and its variability with environmental conditions. Here, we analyzed mercury isotopes in blue sharks Prionace glauca from normoxic waters in the northeastern Atlantic and from the world's largest and shallowest OMZ, located in the northeastern Pacific (NEP). Blue sharks from the NEP OMZ area showed higher Δ199Hg values compared to sharks from the northeastern Atlantic, indicating a reduction in foraging depth of approximately 200 m. Our study suggests for the first time that blue shark feeding depth is altered by expanding OMZs and illustrates the use of mercury isotopes to assess the impacts of ocean deoxygenation on the vertical foraging habitat of pelagic predators.
Show more [+] Less [-]Increasing the Sentinel-2 potential for marine plastic litter monitoring through image fusion techniques Full text
2022
Kremezi, Maria | Kristollari, Viktoria | Karathanassi, Vassilia | Topouzelis, Konstantinos | Kolokoussis, Pol | Taggio, Nicolò | Aiello, Antonello | Ceriola, Giulio | Barbone, Enrico | Corradi, Paolo
Sentinel-2 (S2) images have been used in several projects to detect large accumulations of marine litter and plastic targets. Their limited spatial resolution though hinders the detection of relatively small floating accumulations of marine debris. Thus, this study aims at overcoming this limit through the exploration of fusion with very high-resolution WorldView-2/3 (WV-2/3) images. Various state-of-the-art approaches (component substitution, spectral unmixing, deep learning) were applied on data collected in synchronized acquisitions of plastic targets of various sizes and materials in seawater. The fused images were evaluated for spectral and spatial distortions, as well as their ability to spectrally discriminate plastics from water. Several WV-2/3 band combinations were investigated and five litter indexes were applied. Results showed that: a) the VNIR combination is the optimal one, b) the smallest observable plastic target is 0.6 × 0.6 m² and c) SWIR bands are important for marine litter detection.
Show more [+] Less [-]Ultraphytoplankton community structure in subsurface waters along a North-South Mediterranean transect Full text
2022
Boudriga, Ismail | Thyssen, Melilotus | Zouari, Amel | Garcia, Nicole | Tedetti, Marc | Bel Hassen, Malika
Ultraphytoplankton community structure in subsurface waters along a North-South Mediterranean transect Full text
2022
Boudriga, Ismail | Thyssen, Melilotus | Zouari, Amel | Garcia, Nicole | Tedetti, Marc | Bel Hassen, Malika
Here we assessed the subsurface ultraphytoplanktonic (< 10 μm) community along a North-South round-trip Mediterranean transect as part of a MERITE-HIPPOCAMPE cruise campaign in April–May 2019. Temperature, salinity, and nutrient concentrations in subsurface waters (2–5 m depth) were also measured along the transect. The subsurface ultraphytoplankton community structure was resolved with a spatial resolution of few kilometers and temporal resolution of 30-min intervals using automated pulse shape recording flow cytometry. The subsurface waters were clustered into seven areas based on temperature and salinity characteristics. Synechococcus were by far the most abundant group in all prospected zones, and nanoeukaryotes were the main biomass component, representing up to 51 % of ultraphytoplanktonic carbon biomass. Apparent net primary productivity (NPP) followed a decreasing gradient along the transect from north to south and was mostly sustained by Synechococcus in all zones. These findings are likely to have implications in terms of the trophic transfer of contaminants in planktonic food webs, as they highlight the potential role of nanoplankton in contaminants bioaccumulation processes and the potential role of Synechococcus in a likely transfer via grazing activities.
Show more [+] Less [-]Ultraphytoplankton community structure in subsurface waters along a North-South Mediterranean transect Full text
2022
Boudriga, Ismail | Thyssen, Melilotus | Zouari, Amel | Garcia, Nicole | Tedetti, Marc | Bel Hassen, Malika
Here we assessed the subsurface ultraphytoplanktonic (< 10 μm) community along a North-South round-trip Mediterranean transect as part of a MERITE-HIPPOCAMPE cruise campaign in April–May 2019. Temperature, salinity, and nutrient concentrations in subsurface waters (2–5 m depth) were also measured along the transect. The subsurface ultraphytoplankton community structure was resolved with a spatial resolution of few kilometers and temporal resolution of 30-min intervals using automated pulse shape recording flow cytometry. The subsurface waters were clustered into seven areas based on temperature and salinity characteristics. Synechococcus were by far the most abundant group in all prospected zones, and nanoeukaryotes were the main biomass component, representing up to 51 % of ultraphytoplanktonic carbon biomass. Apparent net primary productivity (NPP) followed a decreasing gradient along the transect from north to south and was mostly sustained by Synechococcus in all zones. These findings are likely to have implications in terms of the trophic transfer of contaminants in planktonic food webs, as they highlight the potential role of nanoplankton in contaminants bioaccumulation processes and the potential role of Synechococcus in a likely transfer via grazing activities.
Show more [+] Less [-]Fugacity-based analysis of polycyclic aromatic hydrocarbon pollution in Izmit Bay, Turkey: An analytical framework for assessment with limited data Full text
2022
Hasanoglu, Sumeyye | Göktaş, Recep Kaya
An analytical framework was proposed for analyzing long-term chemical pollution in a coastal region with limited environmental data. The framework consists of compiling and synthesizing the available knowledge including the chemical's properties and the environmentally relevant data, as well as the data obtained by past monitoring studies. The gathered data is analyzed to assess multimedia fate of the pollutant by using fugacity-based intermedia transport calculations. Uncertainty analysis by applying Monte Carlo simulations is an integrated part of the framework. Dispersion factor (k) values were adopted, enabling a unified and intuitive way to define lognormal uncertainty distributions. The proposed framework was applied to polycyclic aromatic hydrocarbon (PAH) pollution in Izmit Bay, a coastal region in Turkey, impacted by industrialization and population growth. The analysis showed the importance of atmospheric pollution as a PAH source and indicated that Izmit Bay sediments may be at steady state for most PAHs.
Show more [+] Less [-]Identifying marine debris source position using adjoint marginal sensitivity method and stranded beach litter data in Singapore Full text
2022
Gan, Hong Siang | Kanao, Shunsuke | Satō, Tōru | Hellgardt, Klaus | Uchiyama, Yusuke
Movement of marine debris is transboundary and complex, travelling vast distances and accumulating on shorelines. These marine debris wash ashore as stranded beach litter. The objective of this work is to identify release sources of marine debris accumulated along the Singapore coastlines collected by applying a time-backward adjoint marginal sensitivity method and citizen science data of stranded beach litter by a voluntary beach clean-up group. A popular tourist hotspot on the opposite shore was estimated as a possible release source contributing to the marine debris accumulation. This analytical result was validated by population density, industry types, rainfall, and inference from product packaging labels. The use of the citizen science data also illustrated potential as a data source for baseline monitoring and long-term cross-border research that influence policymaking. Future research can be conducted in an expanded domain, considering monsoon effects and instantaneous release events.
Show more [+] Less [-]Transcriptional response of short-term nanoplastic exposure in Monodonta labio Full text
2022
Li, Zhujun | Han, Zhiqiang
Although nanoplastic (NP) pollution across aquatic environments has elicited widespread attention in recent years, its associated risks remain unclear. Using intertidal Monodonta labio as the test organism, RNA-Seq was performed to analyze the expression levels of genes under acute exposure to different concentrations of NPs in this study. A large quantity of differentially expressed genes (DEGs) were detected in response to three concentrations (0.1, 1, and 10 mg/L) of NPs. The expression levels of genes related to immunity, oxidative stress, and apoptosis were altered after NP exposure, and most of them were suppressed. These findings establish the foundation for future research on the biological effects of NP ingestion among aquatic organisms and their potential effects on humans via the consumption of these marine resources. However, further research on DEGs is needed to gain a better understanding of the molecular mechanisms behind their responses to NP toxicity in aquatic organisms.
Show more [+] Less [-]The deposition of atmospheric microplastics in Jakarta-Indonesia: The coastal urban area Full text
2022
Purwiyanto, Anna Ida Sunaryo | Prartono, Tri | Riani, Etty | Naulita, Yuli | Cordova, Muhammad Reza | Koropitan, Alan Frendy
The air pollution in Jakarta has been recorded regularly; meanwhile, the information of atmospheric microplastics is still unknown. This study examines the characteristics (shape, size, and polymer) and deposition rate of atmospheric microplastics in Jakarta. The sample was obtained by putting a rain gauge for 12 months. All microplastic samples were analyzed for polymer using FT-IR. The lowest to the highest percentage of atmospheric microplastic based on shape were foam<fragment<fiber, meanwhile based on size were of 500–1000 μm < 300–500 μm. The detected polymers included polyester, polystyrene, polybutadiene, and polyethylene. The microplastics deposition rate ranged from 3 to 40 particles m⁻²d⁻¹, with an average of 15 particles m⁻²d⁻¹. The rainy season's deposition rate (23.422 particles m⁻²d⁻¹) was higher than the dry season (5.745 particles m⁻²d⁻¹). Our study proves that the atmospheric microplastic exists in Jakarta's air and needs to be considered to monitor by the government regularly.
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