The influence of the trophic level on changes in the mercury concentrations in fish from the coastal zone of the southern Baltic (original) (raw)
Related papers
Oceanological and Hydrobiological Studies, 2012
Cod (Gadus marrhua L), a fish caught in the Baltic Sea, is very popular with consumers. Research on the distribution of mercury in cod tissues and organs was conducted on a group of adult (27) and juvenile (49) individuals in the years 2006-09. Total mercury concentration values in mature cod were always, on average, 1.7 times higher than those in juveniles. The highest HgT concentrations were found in the heart, while the lowest ones were found in the gills and gonads. The essential age-specific differences manifest in a relationship between the mercury concentration in fish muscles and brain. Mature individuals, i.e. of length >80 cm, accumulated Hg in muscles, most likely in an attempt to protect the nervous system from toxic exposure. In young individuals, more mercury was concentrated in the brain than in the muscles.. The distribution of HgT in organs as well as the low value of the [HgT]liver/[HgT]muscle ratio testify to relatively low-level mercury contamination in southern Baltic waters.
The assessment of organic mercury in Baltic fish by use of an in vitro digestion model
Food Chemistry, 2012
The organic mercury content of five commercially valuable fish species (cod, flounder, turbot, perch and herring) was determined by use of an in vitro digestion model in order to assess health risk of fish caught within the Polish Exclusive Economic Zone of the Baltic Sea. Concentrations of total mercury and organic mercury were measured in the muscle tissue of fish and in the products of two-stage gastrointestinal digestion, using atomic absorption spectroscopy (AMA 254). The highest concentrations of organic mercury were found in the muscles of predatory fish that dwell in near-bottom waters. Based on a bioaccessibility estimate obtained from the in vitro digestion model, it was found that only 26-62% of organic mercury, depending on the species of fish, was released into the intestinal lumen during the digestion of muscle. Therefore, to postulate the potential toxicity of fish, based on the organic mercury content of the muscle tissue ingested by consumers, is unfounded. The risk assessment should be carried out on the basis of another parameter -the bioaccessibility of organic mercury.
Organotropism of organic and inorganic mercury in fish from the Vistula Lagoon, Poland
Journal of Elementology, 2019
Our paper presents the results of a study on the concentrations of total (Hg total), organic (CH 3 Hg +) and inorganic (Hg inorg) mercury in freshwater fish from the Vistula Lagoon, coastal waters of the Baltic Sea. Mercury assays were performed on tissues (muscle, skin, gills) and internal organs (heart, spleen, liver, gastrointestinal tract, gonads) of pikeperch, common roach, and common bream. The distributions of Hg total , CH 3 Hg + , and Hg inorg depending on fish species, tissue, or organ and bioaccumulation in tissues and biomagnification in the trophic chain were determined. Interspecific and intraspecific differences in mercury concentrations occurred in fish tissues and organs. Muscles of pikeperch, bream and roach accumulated the highest concentration of CH 3 Hg + , Hg inorg dominating in the gastrointestinal tract of bream and roach. The concentration gradations of Hg total and CH 3 Hg + depending on fish species were as follows: pikeperch > common roach > common bream. For Hg inorg , the gradations were as follows: common bream > common roach > pikeperch. The type of food was a determining criterion for the distribution of mercury forms in the tissues and organs of the fish studied, and quantifiable confirmation of this was the different values of the L:M coefficient (Hg inorg in the hepatic tissue : CH 3 Hg + in muscle). Differences in Hg total , CH 3 Hg + , and Hg inorg concentrations in fish tissues and organs were linked with the food the fish consume, their position in the trophic chain and biomagnification in the food chain.
Acta Veterinaria Brno, 2008
The aim of the study was to evaluate mercury contamination at twelve outlet sites of rivers in the Czech Republic (Labe, Ohře, Vltava, Berounka, Sázava, Otava, Lužnice, Svratka, Dyje, Morava and Odra). As an indicator, we used muscle tissue of the chub (Leuciscus cephalus) caught at selected sites in 2007. A total of 96 fish were examined. Total mercury was determined by atomic absorption spectrophotometry using the AMA 254 analyzer and methylmercury was determined by gas chromatography with electron-capture detection. Total mercury (THg) and methylmercury (MeHg) concentrations ranged 0.039–0.384 mg kg-1 fresh weight and 0.033–0.362 mg kg-1 fresh weight, respectively. Mercury bound in methylmercury (HgMe) made up on average about 82.2% of total mercury. The highest mercury concentrations were found in fish from Obříství, a site on Labe (THg 0.263 ± 0.086 mg kg-1; MeHg 0.256 ± 0.084 mg kg-1). Mercury concentrations in fish from rivers that cross the borders of the Czech Republic (Lab...
Half a century of changing mercury levels in Swedish freshwater fish
Ambio, 2014
The variability of mercury (Hg) levels in Swedish freshwater fish during almost 50 years was assessed based on a compilation of 44 927 observations from 2881 waters. To obtain comparable values, individual Hg concentrations of fish from any species and of any size were normalized to correspond to a standard 1-kg pike [median: 0.69 mg kg⁻¹ wet weight (ww), mean ± SD: 0.84 ± 0.67 mg kg⁻¹ ww]. The EU Environmental Quality Standard of 0.02 mg kg⁻¹ was exceeded in all waters, while the guideline set by FAO/WHO for Hg levels in fish used for human consumption (0.5-1.0 mg kg⁻¹) was exceeded in 52.5 % of Swedish waters after 2000. Different trend analysis approaches indicated an overall long-term decline of at least 20 % during 1965-2012 but trends did not follow any consistent regional pattern. During the latest decade (2003-2012), however, a spatial gradient has emerged with decreasing trends predominating in southwestern Sweden.
Total mercury and methyl mercury contents in fish from lake Päijänne
Environmental Pollution (1970), 1978
The total mercury and methyl mercury contents of freshwater fish f?om Lake P?iijiinne, Finland, are studied. This is the second largest lake in Finland and has been quite heavily contaminated by mercury. The fish from the limnologically cleanest areas had the highest concentrations of mercury. Twelve species of'fish (1774 analyses of total mercury and 157 of methyl mercury) were analysed during a four-year period. Total mercury was measured by flameless atomic absorption and by gas-liquid chromatography. The average mercury concentrationJbr all fish was 0.65 mg/kg on a fresh weight basis, of which 98.7 % was in a methylated form. The concentration of mercury in fish differed in different parts of the lake and also depended on the weight of the fish.
mercury levelS iN fiSh tiSSueS With ANd Without commerciAl vAlue from dANube deltA bioSphere reServe
Journal of environmental protection and ecology
Mercury is one of the few metals which strongly bioconcentrates and biomagnifies, and has only harmful effects with no useful physiological functions when is present in fish and wildlife, and is easily transformed from a less toxic inorganic form to a more toxic organic form in fish tissue. One organic form of mercury, methyl mercury, is of particular concern because it can build up in certain fish. For this study were chosen 5 aquatic complexes (Somova–Parches, Sontea–Fortuna, Matita–Merhei, Rosu–Puiu and Gorgova–Uzlina), of the Danube delta, one of the most important biodiversity reserve in europe. The samples were analysed by cold vapour atomic absorption spec-trometry (cvaaS) procedure, a physical method based on the absorption of radiation at 253.7 nm by mercury vapour. The aim of this study was to evaluate mercury levels in freshwater fish species (approximately 500 samples from different species) from the Danube delta Biosphere reserve. The purpose of this study is to evaluat...
Total and organic mercury in Barents Sea pelagic fish
Bulletin of Environmental Contamination and Toxicology, 1995
One of the main questions, when studying mercury levels in natural samples, is to define how far the measured concentrations correspond to natural-or backgroundlevels or to actual contamination due to human activities. To establish background pristine levels of Hg in the marine environment, areas of very low human activities are often proposed. Arctic and Antarctic waters, together with deep oceans waters, are best suited and provide themselves for such studies. Barents Sea areas were used in this study, even if the existence of an important atmospheric transport of Hg probably caused an increase of Hg levels at a global scale.
Central European Journal of Chemistry, 2011
The determination of mercury in fish typically involves analysis of muscles. For predicting the concentration of mercury in fish muscle on the basis of the analysis of fish scales or fins, the relationship between total mercury concentrations in fish muscles and in fish scales and fins was studied. Mercury content in fish muscles, scales and fins was determined by atomic absorption spectrometry with thermal decomposition of the sample in a flow of oxygen. A number of scale treatments were applied in order to remove impurities and to enhance the prediction quality. For scale treatment, 40 min of washing with DI water in an ultrasonic bath is recommended. A coefficient of determination r2= 0.93 for the relationship between Hg concentrations in muscles and scales was achieved for 40 fish among the different fish species tested (European bream, perch, roach) from the Hamry Reservoir, Czech Republic. With respect to fin sampling, the coefficient of determination r2 for these fish was 0.8...