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Microplastics in offshore fish from the Agulhas Bank, South Africa
2020
Sparks, Conrad | Immelman, Stiaan
The extent and type of microplastic (MP) contamination in South African open ocean marine resources is unknown. This study aims to report on MP ingestion in seven commercially targeted fish species from the Agulhas Bank, south of South Africa. MPs were found in all seven species sampled (N = 105) (Trachurus capensis, Merluccius capensis, Merluccius paradoxus, Etrumeus whiteheadi, Scomber japonicus, Chelidonichthys capensis and Argyrozona argyrozona). MPs were recorded in 86.67% fish sampled, with abundances ranging from 2.8 to 4.6 items/fish. Most MPs were fibres (95.14%), black (38.11%) and ranged from 1000 to 500 μm (35.55%) in size. There was no difference in microplastic concentration in relation to distance from shore (p > .05). This is the first record of MPs in offshore fish from southern Africa and the results indicate that more research is required to assess the extent of MP contamination in the region.
Afficher plus [+] Moins [-]Ingestion of microplastics and mesoplastics by Trachurus declivis (Jenyns, 1841) retrieved from the food of the Australasian gannet Morus serrator: First documented report from New Zealand
2021
Jawad, Laith A. | Adams, Nigel J. | Nieuwoudt, Michel K.
During the process of studying some morphological characters of fish found in the food of the Australasian gannet Morus serrator breeding at Horuhoru Rock and Mahuki islands in the Hauraki Gulf, New Zealand, one carangid specimen of fish species Trachurus declivis out of the 25 fish specimens examined revealed seven small plastic particles in its stomach of different colours: black, red, blue, green, and transparent. Fourier transform infrared (FTIR) spectroscopy was used to identify the compositions of the particles as low and high density polyethylene, poly (methyl methacrylate), polypropylene, and a copolymer of butadiene, acrylonitrile, and methacrylamide. The plastic particles comprised several different shapes and sizes, ranging between 4.5 and 10 mm, and are therefore categorized as micro-and mesoplastic fragments.
Afficher plus [+] Moins [-]Ontogenic and seasonal variations of metal content in a small pelagic fish (Trachurus picturatus) in northwestern African waters
2020
Lozano-Bilbao, Enrique | Lozano, Gonzalo | Jiménez, Sebastián | Jurado-Ruzafa, Alba | Hardisson, Arturo | Rubio, Carmen | Weller, Dailos González | Paz, Soraya | Gutiérrez, Ángel J.
Marine organisms are exposed to great changes induced by human beings due, among others, to discharges into the oceans, increasing marine pollution. For this study, 294 specimens of Trachurus picturatus from the Canary Islands were analyzed during a period of 2 years. The concentration of 11 anthropic metals and trace elements was determined in each individual using the Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique. Statistical analyses were carried out considering the following factors: oceanographic season, maturity of the gonads, size of the specimens, season. Immature specimens had higher concentration in more metals than the mature specimens. This fact may be due to the fact that these specimens require a much higher metabolic rate due to their growth and do not detoxify like mature specimens.
Afficher plus [+] Moins [-]Toxic metals in tissues of fishes from the Black Sea and associated human health risk exposure
2017
Plavan, Gabriel | Jitar, Oana | Teodosiu, Carmen | Nicoară, Mircea | Micu, Dragos | Strungaru, Stefan-Adrian
The anthropogenic activities in the Black Sea area are responsible for toxic metal contamination of sea food products. In this study, several toxic metals: cadmium, lead, nickel, chromium, and copper were quantified in different tissues (digestive tract, muscle, skeleton, skin) of nine fish species (Neogobius melanostomus, Belone belone, Solea solea, Trachurus mediterraneus ponticus, Sardina pilchardus, Engraulis encrasicolus, Pomatomus saltatrix, Sprattus sprattus, Scorpaena porcus) by using atomic absorption spectrometer with a high-resolution continuum source and graphite furnace technique (HR-CS GF-AAS), and the risk of fish meat consumption by the young human population was evaluated. These metals are used in high amounts in industries located near the coastline such as shipyard construction and industrial plants. Toxic metal accumulation depends on fish feeding behavior, abiotic conditions, metal chemistry, and animal physiology. For instance, cadmium was measured in the muscle of the investigated species and average values of 0.0008–0.0338 mg kg⁻¹ were obtained. The lowest average value of this metal was measured at benthic species N. melanostomus and the highest at the pelagic predator T. mediterraneus ponticus. Generally, the highest metal concentration was measured in the digestive tract that has the role of biofilter for these contaminants. The risk of contamination is significantly reduced by avoiding the consumption of certain fish tissues (digestive tract and skin for copper and skeleton for nickel). An estimation of the dietary metal intake to young consumers was realized for each of the studied species of fish from Romanian, Bulgarian, and Turkish waters, during the period 2001–2014 in order to evaluate the risks of chronic exposure in time due to metal toxicity. This estimation is important for the prevention of chronic exposure due to metal toxicity. Food exposure to studied metals showed a negative trend for Romania, Turkey, and Bulgaria based on the data provided by this study. The young consumers were highly exposed to these elements during the 2001–2006 period as proven by the results from this study.
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