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Andersen-Ranberg EU, Leifsson PS, Rigét FF, Søndergaard J, Andersen S, Alstrup AKO, Dietz R, Sonne C. Element Concentrations and Histopathology of Liver and Kidney in West Greenland Ringed Seals ( Pusa hispida). Animals (Basel) 2024; 14:1739. [PMID: 38929358 PMCID: PMC11200747 DOI: 10.3390/ani14121739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Ringed seals are consumed in Greenland and are therefore included as a key biomonitoring species with the focus on pollution exposure and health effects. Ringed seals in Central West Greenland (Qeqertarsuaq) and in North West Greenland (Qaanaaq) were analyzed for metal concentrations in the liver and histological changes in the liver and kidney. The mean liver concentration of mercury in Qaanaaq was 3.73 ± 5.01 µg/g ww (range: 0.28-23.29 µg/g ww), and the mean cadmium concentration was 7.80 ± 8.95 µg/g ww (range: 0.013-38.79 µg/g ww). For Qeqertarsuaq, the liver concentration of mercury was 1.78 ± 1.70 µg/g ww (range: 0.45-8.00 µg/g ww) and the mean cadmium concentration was 11.58 ± 6.32 µg/g ww (range: 0.11-25.45 µg/g ww). Age had a positive effect on the liver concentrations of metals, while no effect was found for sex or histological changes. The prevalence of histological changes in liver tissue decreased in the following order: random pattern mononuclear cell infiltration (92.1%), portal cell infiltration (68.4%), hepatic intracellular fat (18.4%), portal fibrosis (7.9%), focal hepatic fibrosis (7.9%), bile duct hyperplasia/fibrosis (7.9%) and lipid granuloma (2.6%). For kidney tissue, the prevalence of histological changes decreased in the following order: glomerular mesangial deposits (54.1%) > glomerular basement membrane thickening (45.9%) > THD (40%) > tubular hyaline casts (14.0%) > glomerular atrophy (13.5%) > dilated tubules (13.5%) > glomerular hyper-cellularity (10.8%) > mononuclear cell infiltrations (8.1%).
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Affiliation(s)
- Emilie U. Andersen-Ranberg
- Arctic Research Centre (ARC), Department of Ecoscience, Faculty of Technological Sciences, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark; (F.F.R.); (J.S.); (R.D.); (C.S.)
- Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, DK-1870 Frederiksberg, Denmark
| | - Pall S. Leifsson
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Ridebanevej 3, DK-1870 Frederiksberg, Denmark;
| | - Frank F. Rigét
- Arctic Research Centre (ARC), Department of Ecoscience, Faculty of Technological Sciences, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark; (F.F.R.); (J.S.); (R.D.); (C.S.)
| | - Jens Søndergaard
- Arctic Research Centre (ARC), Department of Ecoscience, Faculty of Technological Sciences, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark; (F.F.R.); (J.S.); (R.D.); (C.S.)
| | - Steen Andersen
- Hunters Science, Rådmandsgade 55, DK-2200 Copenhagen N, Denmark;
| | - Aage Kristian Olsen Alstrup
- Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus, Denmark
- Department of Nuclear medicine & PET, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus, Denmark
| | - Rune Dietz
- Arctic Research Centre (ARC), Department of Ecoscience, Faculty of Technological Sciences, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark; (F.F.R.); (J.S.); (R.D.); (C.S.)
| | - Christian Sonne
- Arctic Research Centre (ARC), Department of Ecoscience, Faculty of Technological Sciences, Aarhus University, Frederiksborgvej 399, P.O. Box 358, DK-4000 Roskilde, Denmark; (F.F.R.); (J.S.); (R.D.); (C.S.)
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Page A, Hay C, Marks W, Bennett B, Gribble MO, Noke Durden W, Stolen M, Jablonski T, Gordon N, Kolkmeyer T, Jiang M, Pegg N, Brown H, Burton S. Trace element bioaccumulation, tissue distribution, and elimination in odontocetes stranded in Florida and Georgia, USA over a 15-year period (2007-2021). Heliyon 2024; 10:e25552. [PMID: 38356552 PMCID: PMC10865268 DOI: 10.1016/j.heliyon.2024.e25552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 01/18/2024] [Accepted: 01/29/2024] [Indexed: 02/16/2024] Open
Abstract
Odontocetes obtain nutrients including essential elements through their diet and are exposed to heavy metal contaminants via ingestion of contaminated prey. We evaluated the prevalence, concentration, and tissue distribution of essential and non-essential trace elements, including heavy metal toxicants, in tissue (blubber, kidney, liver, skeletal muscle, skin) and fecal samples collected from 90 odontocetes, representing nine species, that stranded in Georgia and Florida, USA during 2007-2021. Samples were analyzed for concentrations of seven essential (cobalt, copper, iron, manganese, molybdenum, selenium, zinc) and five non-essential (arsenic, cadmium, lead, mercury, thallium) elemental analytes using inductively-coupled plasma mass spectrometry. Risso's dolphins (Grampus griseus) and short-finned pilot whales (Globicephala macrorhynchus) had the highest median concentrations of mercury, cadmium, and lead, while dwarf sperm whales (Kogia sima) had the lowest. Adult pygmy and dwarf sperm whales that stranded in 2019-2021 had higher concentrations of arsenic, copper, iron, lead, manganese, selenium, thallium, and zinc compared to those that stranded in 2010-2018, suggesting an increasing risk of exposure over time. The highest concentrations of many elements (e.g., cadmium, cobalt, copper, manganese, molybdenum, thallium, zinc) were in fecal samples, illustrating the usefulness of this noninvasively collected sample. Aside from fecal samples, hepatic tissues had the highest concentrations of iron, manganese, mercury, molybdenum, and selenium in most species; renal tissues had the highest concentrations of cadmium; skin had the highest concentrations of zinc; and copper, arsenic, and lead concentrations were primarily distributed among the liver and kidneys. Phylogenetic differences in patterns of trace element concentrations likely reflect species-specific differences in diet, trophic level, and feeding strategies, while heterogeneous distributions of elemental analytes among different organ types reflect differences in elemental biotransformation, elimination, and storage. This study illustrates the importance of monitoring toxic contaminants in stranded odontocetes, which serve as important sentinels of environmental contamination, and whose health may be linked to human health.
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Affiliation(s)
- Annie Page
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
| | - Clara Hay
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
- United States Coast Guard Academy, New London, CT, USA
| | - Wendy Marks
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
| | - Baylin Bennett
- University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | | | | | - Nadia Gordon
- Florida Fish & Wildlife Conservation Commission, Fish & Wildlife Research Institute, Jacksonville, FL, USA
| | - Trip Kolkmeyer
- Georgia Department of Natural Resources, Brunswick, GA, USA
| | - Mingshun Jiang
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
| | - Nicole Pegg
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
| | - Hunter Brown
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
| | - Steve Burton
- Florida Atlantic University, Harbor Branch Oceanographic University, Fort Pierce, FL, USA
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von Hellfeld R, Gade C, Doeschate MT, Davison NJ, Brownlow A, Mbadugha L, Hastings A, Paton G. High resolution visualisation of tiemannite microparticles, essential in the detoxification process of mercury in marine mammals. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 342:123027. [PMID: 38016588 DOI: 10.1016/j.envpol.2023.123027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 11/30/2023]
Abstract
The North Sea is an ecologically rich habitat for marine wildlife which has also been impacted by industrial developments and anthropogenic emissions of contaminants such as mercury. Marine mammals are particularly susceptible to mercury exposure, due to their trophic position, long lifespan, and dependence on (increasingly contaminated) aquatic prey species. To mitigate impact, marine mammals can detoxify methylmercury by binding it to selenium-containing biomolecules, creating insoluble mercury selenide granules. Here, liver, kidney, muscle, and brain samples from an adult male bottlenose dolphin (Tursiops truncatus) with known elevated mercury concentrations were analysed through scanning electron microscopy (SEM). Tiemannite (HgSe) deposits were identified in all organs, ranging from 400 nm to 5 μm in diameter, with particle size being organ-dependent. Although reported in other studies, this is the first time that the three-dimensional nature of tiemannite is captured in marine mammal tissue.
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Affiliation(s)
- Rebecca von Hellfeld
- University of Aberdeen, School of Biological Sciences, 23 St Machar Drive, AB23 8UU, Aberdeen, UK; National Decommissioning Centre (NDC), Main Street, AB41 6AA, Newburgh, UK.
| | - Christoph Gade
- University of Aberdeen, School of Biological Sciences, 23 St Machar Drive, AB23 8UU, Aberdeen, UK; National Decommissioning Centre (NDC), Main Street, AB41 6AA, Newburgh, UK
| | - Mariel Ten Doeschate
- Scottish Marine Animal Stranding Scheme (SMASS), University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, 464 Bearsden Road, G61 1QH, Glasgow, UK
| | - Nicolas J Davison
- Scottish Marine Animal Stranding Scheme (SMASS), University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, 464 Bearsden Road, G61 1QH, Glasgow, UK
| | - Andrew Brownlow
- Scottish Marine Animal Stranding Scheme (SMASS), University of Glasgow, School of Biodiversity, One Health & Veterinary Medicine, 464 Bearsden Road, G61 1QH, Glasgow, UK
| | - Lenka Mbadugha
- University of Aberdeen, School of Biological Sciences, 23 St Machar Drive, AB23 8UU, Aberdeen, UK
| | - Astley Hastings
- University of Aberdeen, School of Biological Sciences, 23 St Machar Drive, AB23 8UU, Aberdeen, UK
| | - Graeme Paton
- University of Aberdeen, School of Biological Sciences, 23 St Machar Drive, AB23 8UU, Aberdeen, UK
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Marumoto M, Sakamoto M, Nakamura M, Marumoto K, Tsuruta S. Organ-specific accumulation of selenium and mercury in Indo-Pacific bottlenose dolphins (Tursiops aduncus). Acta Vet Scand 2022; 64:1. [PMID: 35086557 PMCID: PMC8796142 DOI: 10.1186/s13028-021-00607-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 10/04/2021] [Indexed: 11/10/2022] Open
Abstract
Delphinids are top ocean predators and accumulate high concentrations of mercury (Hg) through the food chain, particularly in organs such as liver and kidney, although the proportion of methylmercury (MeHg) is relatively low due to the demethylation process. Total mercury (T-Hg) levels in marine mammals have been shown to correlate with selenium (Se) concentrations, and ingested MeHg that is demethylated may be present in tissues as mercury selenide (HgSe). In this study, we determined T-Hg, MeHg and Se concentrations of three Indo-Pacific bottlenose dolphins (Tursiops aduncus), and we used the individual with the highest Hg concentration for electron probe microanalysis to assess the co-localization of Hg and Se in the tissues. By electron probe microanalysis, we found that Hg and Se were co-localized in large granules in hepatic Kupffer cells and in small granules in hepatocytes. The analysis suggested that MeHg was demethylated in hepatocytes and then phagocytosed by Kupffer cells. In the kidney, Hg and Se were co-localized in the glomerular capillary wall and in interstitial blood vessel walls. Hg and Se were also co-localized in the cytoplasm of large neurons and in glial cells in the cerebrum. Divalent Hg and HgSe cannot cross the blood-brain barrier, suggesting that MeHg is demethylated in the dolphin brain and that binding to Se suppresses Hg toxicity.
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Zeng X, Zhang X, Fan B, Li Y, Jia Z, Huang W, Liu J, Liu G. Pharmacokinetics of Sodium Selenite in Rat Plasma and Tissues After Intragastric Administration. Biol Trace Elem Res 2020; 196:494-501. [PMID: 31656014 DOI: 10.1007/s12011-019-01928-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 10/03/2019] [Indexed: 01/16/2023]
Abstract
The purpose of this research is to investigate the absorption, distribution, excretion, and pharmacokinetics of selenite in rats after intragastric administration, and thus illustrate the efficiency of selenium (Se) supplementation. After a single gavage of sodium selenite, a concentration of Se in plasma and tissues was determined by inductively coupled plasma mass spectrometry (ICP-MS) at different time points. Through fitting the data with the metabolic kinetic model, the corresponding kinetic parameters were determined for plasma and tissues, including kidney, liver, heart, muscle, and gonad. While the metabolic kinetics of sodium selenite in plasma, liver, and kidney of rats was well reflected by a two-compartment open model, that in heart and gonad was fitted to a one-compartment open model, and that in muscle was fitted to a one-compartment open model with a lag time. The results indicate that sodium selenite was absorbed by plasma and tissues quickly and was eliminated slowly after intragastric administration. Based on the results, we propose that multi-supplementation of Se with low dosage is superior to single supplementation with high dosage, in terms of avoiding selenosis.
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Affiliation(s)
- Xueying Zeng
- School of Materials Science and Engineering, Wuhan Institute of Technology, Guanggu 1st road, Wuhan, 430205, People's Republic of China
| | - Xiaotian Zhang
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, #6 Zhuo Daoquan North Road, Wuhan, 430079, People's Republic of China
| | - Bolin Fan
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, #6 Zhuo Daoquan North Road, Wuhan, 430079, People's Republic of China
| | - Yanmei Li
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, #6 Zhuo Daoquan North Road, Wuhan, 430079, People's Republic of China
| | - Ziming Jia
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, #6 Zhuo Daoquan North Road, Wuhan, 430079, People's Republic of China
| | - Wenyao Huang
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, #6 Zhuo Daoquan North Road, Wuhan, 430079, People's Republic of China
| | - Jiafa Liu
- Hubei Provincial Key Laboratory for Applied Toxicology, Hubei Provincial Center for Disease Control and Prevention, #6 Zhuo Daoquan North Road, Wuhan, 430079, People's Republic of China
| | - Gang Liu
- School of Materials Science and Engineering, Wuhan Institute of Technology, Guanggu 1st road, Wuhan, 430205, People's Republic of China.
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Kershaw JL, Hall AJ. Mercury in cetaceans: Exposure, bioaccumulation and toxicity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 694:133683. [PMID: 31394330 DOI: 10.1016/j.scitotenv.2019.133683] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/29/2019] [Accepted: 07/29/2019] [Indexed: 05/27/2023]
Abstract
The fate and transportation of mercury in the marine environment are driven by a combination of anthropogenic atmospheric and aquatic sources, as well as natural geological inputs. Mercury biomagnifies up the food chain, resulting in the bioaccumulation of toxic concentrations in higher trophic organisms even when concentrations in their habitat remain below the threshold level for direct toxicity. As a result, mercury exposure has been recognised as a health concern for both humans and top marine predators, including cetaceans. There appears to be no overall trend in the global measured concentrations reported in cetaceans between 1975 and 2010, although differences between areas show that the highest concentrations in recent decades have been measured in the tissues of Mediterranean odontocetes. There is increasing concern for the impacts of mercury on the Arctic marine ecosystem with changes in water temperatures, ocean currents, and prey availability, all predicted to affect exposure. The accumulation of mercury in various tissues has been linked to renal and hepatic damage as well as reported neurotoxic, genotoxic, and immunotoxic effects. These effects have been documented through studies on stranded and by-caught cetaceans as well as in vitro cell culture experiments. Demethylation of methylmercury and protection by selenium have been suggested as possible mercury detoxification mechanisms in cetaceans that may explain the very high concentrations measured in tissues of some species with no apparent acute toxicity. Thus, the ratio of selenium to mercury is of importance when aiming to determine the impact of the contaminant load at an individual level. The long-term population level effects of mercury exposure are unknown, and continued monitoring of odontocete populations in particular is advised in order to predict the consequences of mercury uptake on marine food chains in the future.
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Affiliation(s)
- Joanna L Kershaw
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews KY16 8LB, UK.
| | - Ailsa J Hall
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews KY16 8LB, UK
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Reyes-Avila AD, Laws EA, Herrmann AD, DeLaune RD, Blanchard TP. Mercury and selenium levels, and Se:Hg molar ratios in freshwater fish from South Louisiana. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2019; 54:238-245. [PMID: 30601090 DOI: 10.1080/10934529.2018.1546495] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/01/2018] [Accepted: 11/04/2018] [Indexed: 06/09/2023]
Abstract
Ample historical evidence has demonstrated the neurotoxicity of organic Hg. However, several studies have suggested that Se effectively sequesters MeHg. The affinity of Hg is up to ≈106 times higher for Se molecules than for comparable sulfur molecules, most of which are components of brain enzymes. The neurotoxicity of MeHg is associated with its binding to Se and the resultant interference with selenoenzymes (Ralston & Raymond, Global Advances in Selenium Research from Theory to Application, 2016). Therefore, having ample Se reserves is an effective way to mitigate MeHg's toxicity. When the molar ratios of Se to Hg in fish exceed 1.0, ingestion of the fish is unlikely to deplete Se reserves. The goal of this study was to determine the Hg and Se levels, and the Se:Hg molar ratios in freshwater fish from south Louisiana and the implications of those ratios with respect to fish consumption and Hg advisories. Five waterbodies were surveyed (University lake, Calcasieu lake, Toledo Bend, the Atchafalaya River and Henderson Lake). The sampled species included black drum (Pogonias cromis), catfish sp., largemouth bass (Micropterus salmoides) and bluegill (Eupomotis macrochirus). All fish were assayed for total Hg and Se. The average Hg concentration was 0.001 µmol g-1 (0.21 ppm), and all concentrations were below the 1 ppm US FDA action level (from 3.1 × 10-5 to 0.003 µmol g-1). Se concentrations exceeded Hg concentrations in most cases. The average Se concentration was 0.003 µmol g-1 (0.27 ppm), all concentrations were around or less than 1.0 ppm (from 3.7 × 10-4 to 0.017 µmol g-1). Hence, the Se:Hg molar ratios were >1 in all fish except largemouth bass from Henderson Lake. In general, Se was detected in sufficient amounts to sequester Hg, but consumption of largemouth bass from Henderson Lake would pose no risk only if anglers followed the posted Hg advisory. For advisory purposes, perhaps, both Hg and Se levels and Se:Hg molar ratios should be considered. In general, the results indicated that risk assessment will require consideration of both the fish species and body of water, because both can influence Se and Hg concentrations and Se:Hg molar ratios.
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Affiliation(s)
- Alexander D Reyes-Avila
- a Department of Environmental Sciences , College of the Coast and Environment, Louisiana State University , Baton Rouge , Louisiana , USA
| | - Edward A Laws
- a Department of Environmental Sciences , College of the Coast and Environment, Louisiana State University , Baton Rouge , Louisiana , USA
| | - Achim D Herrmann
- b Department of Geosciences , Geology, and Geophysics, College of Science, Louisiana State University , Baton Rouge , Louisiana , USA
| | - Ronald D DeLaune
- c Department of Oceanography and Coastal Sciences , College of the Coast and Environment, Louisiana State University , Baton Rouge , Louisiana , USA
| | - Thomas P Blanchard
- c Department of Oceanography and Coastal Sciences , College of the Coast and Environment, Louisiana State University , Baton Rouge , Louisiana , USA
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Gajdosechova Z, Mester Z, Feldmann J, Krupp EM. The role of selenium in mercury toxicity – Current analytical techniques and future trends in analysis of selenium and mercury interactions in biological matrices. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2017.12.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Rojo-Nieto E, Fernández-Maldonado C. Assessing trace elements in striped dolphins from the Strait of Gibraltar: Clues to link the bioaccumulation in the westernmost Mediterranean Sea area and nearest Atlantic Ocean. CHEMOSPHERE 2017; 170:41-50. [PMID: 27974270 DOI: 10.1016/j.chemosphere.2016.12.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 10/24/2016] [Accepted: 12/03/2016] [Indexed: 06/06/2023]
Abstract
Dolphins are considered sentinel species in the marine environment. The Strait of Gibraltar is the only passage between the Mediterranean Sea and the Atlantic Ocean, being the transitional region which connects these two basins and one of the most important routes of cetacean migration worldwide. In this work, eight trace elements (TE) were studied in 45 samples of liver, kidney and muscle, from 15 specimens stranded in this study area. The preliminary results show, among others, the patterns of distribution of the TE in the target organs studied, the influence of sex, length and developmental stage in these TE concentrations and the Se/Hg ratio. Subsequently, the results of TE concentrations in liver have being compared to previous data on S. coeruleoalba from the westernmost Mediterranean Sea and the nearest Atlantic Ocean. For some elements (e.g. for As), concentrations are similar to those obtained from Atlantic samples, despite in other cases (e.g. for Cd) results are lined up with those observed in Mediterranean studies. In addition, in the case of some TE (e.g. Se and Zn) the results are in the middle of those reported for both basins, reinforcing the idea of the Strait of Gibraltar being a transitional zone. Present study is the first research regarding this issue in this outstanding region, aiming to give insights of how this matchless area can help to link TE concentrations observed in these Atlantic and Mediterranean threatened species.
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Affiliation(s)
- Elisa Rojo-Nieto
- Department of Environmental Technologies, Andalusian Center for Marine Science and Technology (CACYTMAR/INMAR), International Campus of Excellence of the Sea, University of Cádiz, Spain; Stranding-Supporting Network, DELPHIS - Ecologistas en Acción Cádiz, c/ San Alejandro s/n., Puerto Real, Spain.
| | - Carolina Fernández-Maldonado
- Center for the Management of the Marine Environment (CEGMA), Andalusian Agency for Environment and Water, (Andalusian Environmental and Spatial Planning Council), Avda. Johan Gütemberg 1, Isla de la Cartuja, Sevilla, Spain
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10
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In vivo formation of natural HgSe nanoparticles in the liver and brain of pilot whales. Sci Rep 2016; 6:34361. [PMID: 27678068 PMCID: PMC5039623 DOI: 10.1038/srep34361] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 09/07/2016] [Indexed: 12/23/2022] Open
Abstract
To understand the biochemistry of methylmercury (MeHg) that leads to the formation of mercury-selenium (Hg-Se) clusters is a long outstanding challenge that promises to deepen our knowledge of MeHg detoxification and the role Se plays in this process. Here, we show that mercury selenide (HgSe) nanoparticles in the liver and brain of long-finned pilot whales are attached to Se-rich structures and possibly act as a nucleation point for the formation of large Se-Hg clusters, which can grow with age to over 5 μm in size. The detoxification mechanism is fully developed from the early age of the animals, with particulate Hg found already in juvenile tissues. As a consequence of MeHg detoxification, Se-methionine, the selenium pool in the system is depleted in the efforts to maintain essential levels of Se-cysteine. This study provides evidence of so far unreported depletion of the bioavailable Se pool, a plausible driving mechanism of demonstrated neurotoxic effects of MeHg in the organism affected by its high dietary intake.
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Hansen AMK, Bryan CE, West K, Jensen BA. Trace Element Concentrations in Liver of 16 Species of Cetaceans Stranded on Pacific Islands from 1997 through 2013. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 70:75-95. [PMID: 26283019 PMCID: PMC4988065 DOI: 10.1007/s00244-015-0204-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 07/27/2015] [Indexed: 05/06/2023]
Abstract
The impacts of anthropogenic contaminants on marine ecosystems are a concern worldwide. Anthropogenic activities can enrich trace elements in marine biota to concentrations that may negatively impact organism health. Exposure to elevated concentrations of trace elements is considered a contributing factor in marine mammal population declines. Hawai'i is an increasingly important geographic location for global monitoring, yet trace element concentrations have not been quantified in Hawaiian cetaceans, and there is little trace element data for Pacific cetaceans. This study measured trace elements (Cr, Mn, Cu, Zn, As, Se, Sr, Cd, Sn, Hg, and Pb) in liver of 16 species of cetaceans that stranded on U.S. Pacific Islands from 1997 to 2013, using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) (n = 31), and direct mercury analysis atomic absorption spectrometry (DMA-AAS) (n = 43). Concentration ranges (μg/g wet mass fraction) for non-essential trace elements, such as Cd (0.0031-58.93) and Hg (0.0062-1571.75) were much greater than essential trace elements, such as Mn (0.590-17.31) and Zn (14.72-245.38). Differences were found among age classes in Cu, Zn, Hg, and Se concentrations. The highest concentrations of Se, Cd, Sn, Hg, and Pb were found in one adult female false killer whale (Pseudorca crassidens) at concentrations that are known to affect health in marine mammals. The results of this study establish initial trace element concentration ranges for Pacific cetaceans in the Hawaiian Islands region, provide insights into contaminant exposure of these marine mammals, and contribute to a greater understanding of anthropogenic impacts in the Pacific Ocean.
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Affiliation(s)
- Angela M K Hansen
- College of Natural and Computational Science, Hawaii Pacific University, 45-045 Kamehameha Highway, Kaneohe, HI, 96744-5297, USA
| | - Colleen E Bryan
- Chemical Sciences Division, Hollings Marine Laboratory, National Institute of Standards and Technology, 331 Fort Johnson Road, Charleston, SC, 29412, USA.
| | - Kristi West
- College of Natural and Computational Science, Hawaii Pacific University, 45-045 Kamehameha Highway, Kaneohe, HI, 96744-5297, USA
| | - Brenda A Jensen
- College of Natural and Computational Science, Hawaii Pacific University, 45-045 Kamehameha Highway, Kaneohe, HI, 96744-5297, USA
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García-Alvarez N, Fernández A, Boada LD, Zumbado M, Zaccaroni A, Arbelo M, Sierra E, Almunia J, Luzardo OP. Mercury and selenium status of bottlenose dolphins (Tursiops truncatus): A study in stranded animals on the Canary Islands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 536:489-498. [PMID: 26232758 DOI: 10.1016/j.scitotenv.2015.07.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 07/07/2015] [Accepted: 07/07/2015] [Indexed: 06/04/2023]
Abstract
The mercury (Hg) level in the marine environment has tripled in recent decades, becoming a great concern because of its high toxic potential. This study reports Hg and selenium (Se) status, and the first Se/Hg molar ratio assessment in bottlenose dolphins (Tursiops truncatus) inhabiting the waters of the Canary Islands. Total Hg and Se concentrations were determined in the blubber and liver collected from 30 specimens stranded along the coasts of the archipelago from 1997 to 2013. The median values for total Hg in the blubber and liver were 80.83 and 223.77 μg g(-1) dry weight (dw), and the median levels for Se in both tissues were 7.29 and 68.63 μg g(-1) dw, respectively. Hg concentrations in the liver were lower than 100 μg g(-1) wet weight (ww), comparable to those obtained in bottlenose dolphins from the North Sea, the Western Atlantic Ocean and several locations in the Pacific Ocean. The Mediterranean Sea and South of Australia are the most contaminated areas for both elements in this cetacean species. In addition, it must be stressed that the levels of Hg and Se in the liver showed an increasing trend with the age of the animals. As expected, a strong positive correlation between Hg and Se was observed (rs=0.960). Surprisingly, both younger and older specimens had a Se/Hg molar ratio different from 1, suggesting that these individuals may be at greater toxicological risk for high concentrations of both elements or a deficiency of Se without a protective action against Hg toxicity.
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Affiliation(s)
- Natalia García-Alvarez
- Unit of Histology and Pathology, Institute of Animal Health (IUSA), Veterinary School, University of Las Palmas de Gran Canaria, 35413 Arucas, Las Palmas, Spain.
| | - Antonio Fernández
- Unit of Histology and Pathology, Institute of Animal Health (IUSA), Veterinary School, University of Las Palmas de Gran Canaria, 35413 Arucas, Las Palmas, Spain
| | - Luis D Boada
- Toxicology Unit, Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain
| | - Manuel Zumbado
- Toxicology Unit, Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain
| | - Annalisa Zaccaroni
- Department of Veterinary Medical Sciences, University of Bologna, Research Group on Large Pelagic Vertebrates, Viale Vespucci 2, 47042 Cesenatico, FC, Italy
| | - Manuel Arbelo
- Unit of Histology and Pathology, Institute of Animal Health (IUSA), Veterinary School, University of Las Palmas de Gran Canaria, 35413 Arucas, Las Palmas, Spain
| | - Eva Sierra
- Unit of Histology and Pathology, Institute of Animal Health (IUSA), Veterinary School, University of Las Palmas de Gran Canaria, 35413 Arucas, Las Palmas, Spain
| | - Javier Almunia
- Loro Parque Foundation, Camino Burgado, 38400 Puerto de la Cruz (Tenerife), Santa Cruz de Tenerife, Spain
| | - Octavio P Luzardo
- Toxicology Unit, Research Institute of Biomedical and Health Sciences (IUIBS), University of Las Palmas de Gran Canaria, 35016 Las Palmas de Gran Canaria, Spain
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Sakamoto M, Itai T, Yasutake A, Iwasaki T, Yasunaga G, Fujise Y, Nakamura M, Murata K, Chan HM, Domingo JL, Marumoto M. Mercury speciation and selenium in toothed-whale muscles. ENVIRONMENTAL RESEARCH 2015; 143:55-61. [PMID: 26436307 DOI: 10.1016/j.envres.2015.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 09/07/2015] [Accepted: 09/09/2015] [Indexed: 06/05/2023]
Abstract
Mercury accumulates at high levels in marine mammal tissues. However, its speciation is poorly understood. The main goal of this investigation was to establish the relationships among mercury species and selenium (Se) concentrations in toothed-whale muscles at different mercury levels. The concentrations of total mercury (T-Hg), methylmercury (MeHg), inorganic mercury (I-Hg) and Se were determined in the muscles of four toothed-whale species: bottlenose dolphins (n=31), Risso's dolphins (n=30), striped dolphins (n=29), and short-finned pilot whales (n=30). In each species, the MeHg concentration increased with increasing T-Hg concentration, tending to reach a plateau. In contrast, the proportion of MeHg in T-Hg decreased from 90-100% to 20-40%. The levels of T-Hg and Se showed strong positive correlations. Se/I-Hg molar ratios rapidly decreased with the increase of I-Hg and reached almost 1 in all species. These results suggested that the demethylated MeHg immediately formed Se/I-Hg equimolar complex of mercury selenide (HgSe) in their muscles. In addition, an X-ray absorption fine structure analysis (XAFS) of a bottlenose dolphin muscle confirmed that the dominant chemical form of the Se/I-Hg equimolar complex was HgSe. HgSe was mainly localized in cells near the endomysium using electron probe microanalysis (EPMA). These results suggested that the demethylated MeHg finally deposits within muscle cells of bottlenose dolphin as an inert HgSe.
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Affiliation(s)
- Mineshi Sakamoto
- National Institute for Minamata Disease, Hama 4058-18, Minamata, Kumamoto 867-0008, Japan.
| | - Takaaki Itai
- Ehime University, Bunkyo 2-5, Matsuyama 790-8755, Japan
| | - Akira Yasutake
- National Institute for Minamata Disease, Hama 4058-18, Minamata, Kumamoto 867-0008, Japan
| | - Toshihide Iwasaki
- Tohoku National Fisheries Research Institute, 25-259 Shimomekurakubo, Aomori 031-0841, Japan
| | - Genta Yasunaga
- Institute of Cetacean Research, 4-5 Toyomi, Tokyo 104-0055, Japan
| | - Yoshihiro Fujise
- Institute of Cetacean Research, 4-5 Toyomi, Tokyo 104-0055, Japan
| | - Masaaki Nakamura
- National Institute for Minamata Disease, Hama 4058-18, Minamata, Kumamoto 867-0008, Japan
| | - Katsuyuki Murata
- Akita University School of Medicine, Hondo 1-1-1, Akita 010-8543, Japan
| | - Hing Man Chan
- University of Ottawa, Marie-Curie, Ottawa, ON, Canada KIN 6N5
| | - José L Domingo
- School of Medicine, IISPV, Universitat "Rovira i Virgili", Reus, Spain
| | - Masumi Marumoto
- National Institute for Minamata Disease, Hama 4058-18, Minamata, Kumamoto 867-0008, Japan
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Gui D, Yu RQ, Sun Y, Chen L, Tu Q, Mo H, Wu Y. Mercury and selenium in stranded Indo-Pacific humpback dolphins and implications for their trophic transfer in food chains. PLoS One 2014; 9:e110336. [PMID: 25310100 PMCID: PMC4195725 DOI: 10.1371/journal.pone.0110336] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 09/18/2014] [Indexed: 11/18/2022] Open
Abstract
As top predators in the Pearl River Estuary (PRE) of China, Indo-Pacific humpback dolphins (Sousa chinensis) are bioindicators for examining regional trends of environmental contaminants in the PRE. We examined samples from stranded S. chinensis in the PRE, collected since 2004, to study the distribution and fate of total mercury (THg), methylmercury (MeHg) and selenium (Se) in the major tissues, in individuals at different ages and their prey fishes from the PRE. This study also investigated the potential protective effects of Se against the toxicities of accumulated THg. Dolphin livers contained the highest concentrations of THg (32.34±58.98 µg g−1 dw) and Se (15.16±3.66 µg g−1 dw), which were significantly different from those found in kidneys and muscles, whereas the highest residue of MeHg (1.02±1.11 µg g−1 dw) was found in dolphin muscles. Concentrations of both THg and MeHg in the liver, kidney and muscle of dolphins showed a significantly positive correlation with age. The biomagnification factors (BMFs) of inorganic mercury (Hginorg) in dolphin livers (350×) and MeHg in muscles (18.7×) through the prey fishes were the highest among all three dolphin tissues, whereas the BMFs of Se were much lower in all dolphin tissues. The lower proportion of MeHg in THg and higher Se/THg ratios in tissues were demonstrated. Our studies suggested that S. chinensis might have the potential to detoxify Hg via the demethylation of MeHg and the formation of tiemannite (HgSe) in the liver and kidney. The lower threshold of hepatic THg concentrations for the equimolar accumulation of Se and Hg in S. chinensis suggests that this species has a greater sensitivity to THg concentrations than is found in striped dolphins and Dall’s porpoises.
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Affiliation(s)
- Duan Gui
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Ri-Qing Yu
- Department of Biology, University of Texas at Tyler, Tyler, Texas, United States of America
| | - Yong Sun
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Laiguo Chen
- Urban Environment and Ecology Research Center, South China Institute of Environmental Sciences (SCIES), Ministry of Environmental Protection, Guangzhou, China
| | - Qin Tu
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Hui Mo
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Yuping Wu
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, China
- * E-mail:
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Cáceres-Saez I, Dellabianca NA, Goodall RNP, Cappozzo HL, Guevara SR. Mercury and selenium in subantarctic Commerson's dolphins (Cephalorhynchus c. commersonii). Biol Trace Elem Res 2013; 151:195-208. [PMID: 23225076 DOI: 10.1007/s12011-012-9555-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 11/18/2012] [Indexed: 10/27/2022]
Abstract
Total mercury (THg) and selenium (Se) concentrations were determined in hepatic, renal, and muscle tissues of seven specimens of Commerson's dolphins incidentally captured in artisanal fisheries of Tierra del Fuego, Argentina, by instrumental neutron activation analysis. Liver yielded the mean highest concentration of THg 9.40 (9.92) μg g(-1) dry weight (DW) (standard deviation of the average in parenthesis); kidney and muscle showed similar values, ranging from 2.34 to 3.63 μg g(-1) DW. Selenium concentrations were similar in hepatic and renal tissues, with values from 13.62 to 14.56 μg g(-1) DW; the lowest concentration was observed in muscle, 4.13 (2.05) μg g(-1) DW. Among the specimens analyzed, the maximum concentrations of THg and Se were observed in the single adult female studied. An increasing age trend is observed for THg concentrations in tissues analyzed. The molar ratio of Se/Hg in the hepatic, renal, and muscle tissues were 8.7 (9.6), 13.2 (9.5), and 9.0 (11.4), respectively, suggesting Se protection against Hg toxicity. Silver concentrations in the three tissues were included, and the Se/(Hg + 0.5×Ag) molar ratio showed values closer to 1. Both Hg and Se concentrations in liver and kidney were comparable to those found in other small odontocetes from Argentine and Brazilian waters. This study constitutes the first joint description reported of Hg and Se concentrations in liver, kidney, and muscle of the Commerson's dolphin species.
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Affiliation(s)
- Iris Cáceres-Saez
- Laboratorio de Ecología, Comportamiento y Mamíferos Marinos (LECyMM), Museo Argentino de Ciencias Naturales Bernardino Rivadavia (MACN-CONICET), Buenos Aires, Argentina.
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Agusa T, Nomura K, Kunito T, Anan Y, Iwata H, Tanabe S. Accumulation of trace elements in harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada. MARINE POLLUTION BULLETIN 2011; 63:489-499. [PMID: 21411109 DOI: 10.1016/j.marpolbul.2011.02.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 12/23/2010] [Accepted: 02/11/2011] [Indexed: 05/30/2023]
Abstract
Nineteen trace elements were determined in liver, muscle, kidney, gonads, and hair of 18 harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada. Concentrations of V, Mn, Fe, Cu, Mo, Ag, and Hg in the liver, Co, Cd, and Tl in the kidney, and Ba and Pb in the hair were significantly higher than those in other tissues. Significant positive correlations between Hg concentrations in the hair, and liver, kidney and testis imply usefulness of the hair sample for non-destructive monitoring of Hg in the harp seals. It is suggested that whereas Hg preferentially accumulates in the liver, the accumulation in other tissues is induced at higher hepatic Hg levels. In contrast, Se may not be accumulated in other tissues compared with the liver even at higher hepatic Hg levels because of the presence of excess Se for Hg detoxification in other tissues.
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Affiliation(s)
- Tetsuro Agusa
- Department of Legal Medicine, Shimane University Faculty of Medicine, Enya 89-1, Izumo 693-8501, Japan
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Wallschläger D, Feldmann J. Formation, Occurrence, Significance, and Analysis of Organoselenium and Organotellurium Compounds in the Environment. ORGANOMETALLICS IN ENVIRONMENT AND TOXICOLOGY 2010. [DOI: 10.1039/9781849730822-00319] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Among all environmentally-relevant trace elements, selenium has one of the most diverse organic chemistries. It is also one of the few trace elements that may biomagnify in food chains under certain conditions. Yet, the exact chemical forms of selenium involved in the uptake into organisms and transfer to higher trophic levels, as well as the biochemical mechanisms that lead to their subsequent metabolism in organisms, are still not well understood. This is in part due to the analytical challenges associated with measuring the myriad of discrete Se species occurring in organisms. While there are generalized concepts of selenium metabolism, there is a lack of conclusive analytical evidence supporting the existence of many postulated intermediates. Likewise, there is a disconnect between the major selenium species encountered in abiotic compartments (waters, soils, and sediment), and those found in organisms, which renders the qualitative and quantitative description of the bioaccumulation process uncertain. Here, we summarize the knowledge on important selenium and tellurium species in all environmental compartments, and identify gaps and uncertainties in the existing body of knowledge, with emphasis on problems associated with past and current analytical methodology.
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Affiliation(s)
- Dirk Wallschläger
- Environmental & Resource Sciences Program and Department of Chemistry, Trent University 1600 West Bank Dr. Peterborough ON K9J 7B8 Canada
| | - Jörg Feldmann
- Trace Element Speciation Laboratory (TESLA), College of Physical Science, University of Aberdeen Meston Walk Aberdeen Scotland AB24 3UE UK
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Ralston NVC, Blackwell JL, Raymond LJ. Importance of molar ratios in selenium-dependent protection against methylmercury toxicity. Biol Trace Elem Res 2007; 119:255-68. [PMID: 17916948 DOI: 10.1007/s12011-007-8005-7] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 10/23/2022]
Abstract
The influence of dietary selenium (Se) on mercury (Hg) toxicity was studied in weanling male Long Evans rats. Rats were fed AIN-93G-based low-Se torula yeast diets or diets augmented with sodium selenite to attain adequate- or rich-Se levels (0.1, 1.0 or 15 micromol/kg, respectively) These diets were prepared with no added methylmercury (MeHg) or with moderate- or high-MeHg (0.2, 10 or 60 micromol/kg, respectively). Health and weights were monitored weekly. By the end of the 9-week study, MeHg toxicity had impaired growth of rats fed high-MeHg, low-Se diets by approximately 24% (p < 0.05) compared to the controls. Growth of rats fed high-MeHg, adequate-Se diets was impaired by approximately 8% (p < 0.05) relative to their control group, but rats fed high-MeHg, rich-Se diets did not show any growth impairment. Low-MeHg exposure did not affect rat growth at any dietary Se level. Concentrations of Hg in hair and blood reflected dietary MeHg exposure, but Hg toxicity was more directly related to the Hg to Se ratios. Results support the hypothesis that Hg-dependent sequestration of Se is a primary mechanism of Hg toxicity. Therefore, Hg to Se molar ratios provide a more reliable and comprehensive criteria for evaluating risks associated with MeHg exposure.
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Affiliation(s)
- Nicholas V C Ralston
- Energy and Environmental Research Center, University of North Dakota, 15 North 23rd Street, Stop 9018, Grand Forks, ND 58202, USA.
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