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Marine environment microfiber contamination: Global patterns and the diversity of microparticle origins
2018
Barrows, A.P.W. | Cathey, S.E. | Petersen, C.W.
Microplastic and microfiber pollution has been documented in all major ocean basins. Microfibers are one of the most common microparticle pollutants along shorelines. Over 9 million tons of fibers are produced annually; 60% are synthetic and ∼25% are non-synthetic. Non-synthetic and semi-synthetic microfibers are infrequently documented and not typically included in marine environment impact analyses, resulting in underestimation of a potentially pervasive and harmful pollutant. We present the most extensive worldwide microparticle distribution dataset using 1-liter grab samples (n = 1393). Our citizen scientist driven study shows a global microparticle average of 11.8 ± 24.0 particles L−1 (mean ± SD), approximately three orders of magnitude higher than global model predictions. Open ocean samples showed consistently higher densities than coastal samples, with the highest concentrations found in the polar oceans (n = 51), confirming previous empirical and theoretical studies. Particles were predominantly microfibers (91%) and 0.1–1.5 mm in length (77%), a smaller size than those captured in the majority of surface studies. Using μFT-IR we determined the material types of 113 pieces; 57% were classified as synthetic, 12% as semi-synthetic, and 31% as non-synthetic. Samples were taken globally, including from coastal environments and understudied ocean regions. Some of these sites are emerging as areas of concentrated floating plastic and anthropogenic debris, influenced by distant waste mismanagement and/or deposition of airborne particles. Incorporation of smaller-sized microfibers in oceanographic models, which has been lacking, will help us to better understand the movement and transformation of synthetic, semi-synthetic and non-synthetic microparticles in regional seas and ocean basins.
Afficher plus [+] Moins [-]Microplastic and macroplastic ingestion by a deep diving, oceanic cetacean: The True's beaked whale Mesoplodon mirus
2015
Lusher, Amy L. | Hernandez-Milian, Gema | O'Brien, Joanne | Berrow, Simon | O'Connor, Ian | Officer, Rick
When mammals strand, they present a unique opportunity to obtain insights into their ecology. In May 2013, three True's beaked whales (two adult females and a female calf) stranded on the north and west coasts of Ireland and the contents of their stomachs and intestines were analysed for anthropogenic debris. A method for identifying microplastics ingested by larger marine organisms was developed. Microplastics were identified throughout the digestive tract of the single whale that was examined for the presence of microplastics. The two adult females had macroplastic items in their stomachs. Food remains recovered from the adult whales consisted of mesopelagic fish (Benthosema glaciale, Nansenia spp., Chauliodius sloani) and cephalopods, although trophic transfer has been discussed, it was not possible to ascertain whether prey were the source of microplastics. This is the first study to directly identify microplastics <5 mm in a cetacean species.
Afficher plus [+] Moins [-]Trace metals and polycyclic aromatic hydrocarbons in the Eastern Mediterranean sediments: Concentration ranges as a tool for quality control of large data collections
2022
Lipizer, M. | Berto, D. | Cermelj, B. | Fafandjel, M. | Formalewicz, M. | Hatzianestis, I. | Ilijanić, N. | Kaberi, H. | Kralj, M. | Matijevic, S. | Molina Jack, M.e. | Parinos, C. | Tronczynski, Jacek | Giani, M.
Assessing the status of marine pollution at regional and sub-regional scales requires the use of comparable and harmonized data provided by multiple institutions, located in several countries. Standardized data management and quality control are crucial for supporting a coherent evaluation of marine pollution. Taking the Eastern Mediterranean Sea as a case study, we propose an approach to improve the quality control procedures used for sediment pollution data, thus supporting a harmonized environmental assessment. The regional ranges of contaminant concentrations in sediments were identified based on an in-depth literature review, and the lowest measured concentrations were evaluated to determine the “background concentrations” of chemical substances not yet targeted in the Mediterranean Sea. In addition, to verify the suitability of the approach for validating large data collections provided by multiple sources, the determined ranges were used to validate a regional dataset available through EMODnet data infrastructure.
Afficher plus [+] Moins [-]Characteristics of metal pollution and multi-isotopic signatures for C, Cu, Zn, and Pb in coastal sediments from special management areas in Korea
2023
Jeong, Hyeryeong | Lee, Yeonjung | Moon, Hyo-bang | Ra, Kongtae
The concentrations and isotopic compositions of carbon (C), copper (Cu), zinc (Zn), and lead (Pb) in coastal sediments were analyzed to identify potential pollution sources. High concentrations of total organic carbon (TOC) and metals were found close to cities and industrial areas. The isotopic compositions of C, Cu, Zn, and Pb tended to decrease as their concentrations increased. Bi-plots between δ65Cu and δ66Zn showed that the isotopic compositions in most coastal sediments, except sediments around a smelter, were similar to the isotopic compositions of road dust in urban and industrial areas of Korea. Our results suggest that heavy metal pollution in coastal sediments is greatly influenced by the pollution source, such that most metals originate from traffic and industrial activities in the urban environment. This analysis of multiple isotopes provides insights concerning the transport mechanisms and clarifies potential sources of metal contamination in coastal environments.
Afficher plus [+] Moins [-]"Non-traditional" stable isotopes applied to the study of trace metal contaminants in anthropized marine environments
2022
Ferreira Araujo, Daniel | Knoery, Joel | Briant, Nicolas | Vigier, Nathalie | Ponzevera, Emmanuel
The advent of Multicollector ICP-MS advent inaugurated the analysis of new metal isotope systems, the so-called “non-traditional” isotopes. They are now available tools to study geochemical and ecotoxicological aspects of marine metal contamination and hence, to push the frontiers of our knowledge. However, such applications are still in their infancy, and an accessible state-of-the-art describing main applications, obstacles, gaps, and directions for further development was missing from the literature. This paper fills this gap and aims to encourage the marine scientific community to explore the contributions of this newly available information for the fields of chemical risk assessment, biomonitoring, and trophic transfer of metal contaminants. In the current “Anthropocene” epoch, metal contamination will continue to threaten marine aquatic ecosystems, and “non-traditional” isotopes can be a valuable tool to detect human-induced changes across time-space involving metal contaminants, and their interaction with marine biota.
Afficher plus [+] Moins [-]Factors that influence trace element levels in blood and feathers of Pygoscelis penguins from South Shetland Islands, Antarctica
2021
Padilha, J. A. | Carvalho, G. O. | Espejo, W. | Souza, J. S. | Pizzochero, A. C. | Cunha, L. S. T. | Costa, E. S. | Pessoa, A. R. L. | Almeida, A. P. | Torres, J. P. M. | Lepoint, G. | Michel, Loic | Das, K. | Dorneles, P. R.
Contaminant levels are lower in Antarctica than elsewhere in the world because of its low anthropogenic activities. However, the northern region of the Antarctic Peninsula, is close to South America and experiences the greatest anthropogenic pressure in Antarctica. Here, we investigated, in two Antarctic Peninsula islands, intra and interspecific factors that influence the concentrations of 17 trace elements (TEs) in blood and feathers of three penguin species breeding sympatrically in relation to their trophic ecology assessed via a stable isotopic approach (C, N and S). Geographical location, foraging zone (delta C-13 and delta S-34) and diet influences the interspecific difference, and sex and maturity stage diet influence the intraspecific difference of Pygoscelis penguins. Penguins from Livingston showed higher values (mean, ng. g(-1), dry weight - dw) of Zn (103), Mn (0.3), and Fe (95) than those from King George Island (Zn: 80, Mn: 1.9, and Fe: 11). Gender-related differences were observed, as males showed significantly higher values (mean, ng. g(-1), dw) of Rb (3.4) and delta N-15 in blood of gentoo, and Ca (1344) in Adelie feathers. Chicks of gentoo and Adelie presented higher Zn, Mg, Ca, and Sr and lower C-13 values in blood than adults. The highest concentrations (mean, ng. g(-1), dw) of Cd (0.2) and Cu (26), and the lowest delta N-15 values were found in chinstrap. Geographical, intraspecific (i.e., ontogenetic and gender-related) and interspecific differences in feeding seemed to have influenced TE and stable isotope values in these animals. The TE bioaccumulation by penguins may have also been influenced by natural enrichment in environmental levels of these elements, which seems to be the case for Fe, Zn, and Mn. However, the high level of some of the TEs (Mn, Cd, and Cr) may reflect the increase of local and global human activities.
Afficher plus [+] Moins [-]Environmental friendly Polyacrylonitrile nanofiber mats encapsulated and coated with green algae mediated Titanium oxide nanoparticles for efficient oil spill adsorption
2022
Poddar, Mrinal | Lakshmi, G.B.V.S. | Sharma, Mahima | Chaudhary, Navneet | Nigam, Subhasha | Joshi, Monika | Solanki, Pratima R.
Oil spill causes extreme environmental damage, from aquatic life to seabirds, disrupting the entire ecosystem. Herein, we have synthesized high scale, economical and bio-compatible, green algae mediated Titanium oxide (TiO₂) nanoparticles and Polyacrylonitrile (PAN) nanofiber mats. We have studied the effect of encapsulation and coating of TiO₂ nanoparticles over nanofiber mats for highly efficient oil spill adsorption. TiO₂ encapsulated and coated PAN (TECP) nanofibers showed a maximum of 62.34 g g⁻¹ adsorption capacity of petroleum oil from the water surface. Moreover, the composite mats show maximum adsorption within 45 s for up to 5 repeated cycles. Further, it has been observed that the adsorption capacity has increased by increasing the weight of the composite nanofiber mats, which confirms its commercial applicability. Thus, this work provides rapid, large-scale, economical, bio-compatible, and highly effective adsorbents for oil spill cleaning and extraction over natural waterbodies.
Afficher plus [+] Moins [-]Assessment of heavy metal contamination in surface sediments off the Dongying coast, Bohai Sea
2022
Wu, Zhen | Dong, Yingwei | Liu, Rongbo | Liu, Longlong | Gao, Junfeng | Song, Wei | Zhang, Shengjiang | Qiu, Jiandong
In this study, 214 surface sediment samples were collected from the offshore area of the Dongying coast and were analysed for heavy metals; particularly, their concentrations and pollution status were evaluated. The copper (Cu) and chromium (Cr) distributions were similar, their concentrations were the highest in the northeast areas and the Xiaoqing River estuary, where dominated by fine-grained sediments. Higher concentrations of lead (Pb), zinc (Zn), cadmium (Cd), and arsenic (As) were generally found in the offshore area of the study location, and the highest Cd concentration was observed in the Xiaoqing River estuary. The sediments were not polluted by Cu, Pb, Zn, and Cr; they were not polluted or moderately polluted by Cd and As. Results of the principal component analysis indicated that Cu, Pb, Zn, and Cr were derived from natural sources and Cd and As were derived from anthropogenic sources.
Afficher plus [+] Moins [-]Spatiotemporal variations in marine litter along the Gulf of Guinea coastline, Araromi seaside, Nigeria
2022
Fadare, Oluniyi O. | Akinbile, Adewale A. | Makinde, Oladotun Wasiu | Ogundele, K.T. | Ajagbe, Eyitayo F. | Ilechukwu, Ifenna
This study assessed the seasonal variation in the magnitude of marine litter along the Gulf of Guinea coastline, Araromi seaside, Nigeria with a survey of twenty sampling sites. The total number of litter items collected was 29,029 comprising 7358 and 21,671 items in the dry and rainy season respectively. The average number of items per square meter was higher in the rainy season (1.80 ± 0.35) than in the dry season (0.61 ± 0.19). Plastic materials dominated the litter composition with 86 % and 91.8 % in the dry and rainy season respectively. The beach cleanliness assessed as clean coast index (CCI) depicted the beach as dirty (12.26 ± 3.74) during the dry season and extremely dirty (36.13 ± 6.91) in the rainy season. The hazardous item index (HII) also showed the coastline was littered with hazardous items. These results provide baseline data for marine litter management along the Gulf of Guinea coastlines and other coastlines in Africa.
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