Concentrations of methylmercury, total mercury and selenium in marine mammal tissues were determined in liver, muscle, skin (muktuk) and blubber of belugas, ringed seals and narwhal, using atomic absorption and capillary gas chromatography with ECD detection. Mean MeHg levels in the types of tissues analysed, except blubber, generally exceeded the Canadian Federal Consumption Guideline for mercury in fish (0.5 micrograms/g wet wt.). A spatial trend of higher MeHg levels in western compared to eastern Arctic belugas and ringed seals was found which followed a similar trend observed for total mercury. Factors which could explain this trend are discussed. Robust linear regression of MeHg on total Hg and MeHg on age of animals was performed and a strong correlation between the two variables was found in each case. The ratio of MeHg to total mercury as indicated by the regression coefficients was close to one for muscle and skin (muktuk) while for liver it was < 1. The mean percentage of MeHg in the liver of marine mammals was 3-12% of the total Hg in this tissue depending on species and location. It is postulated that the formation and deposition of mercuric selenide in the liver is part of the demethylation process in this tissue. This is based on the relatively low fraction of MeHg in the liver not withstanding the fact that the predominant form of mercury taken up via food is MeHg. The long half-life for total mercury and the relatively short half-life for MeHg in this organ are in accord with this postulate as is the 1:1 stoichiometric relationship between mercury and selenium in the liver.
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http://dx.doi.org/10.1016/s0048-9697(98)00192-2 | DOI Listing |
Environ Res
January 2025
Facultad de Ciencias Básicas. Universidad de Córdoba. Cra 6 # 77-305, Montería, 230002. Córdoba, Colombia. Electronic address:
In marine ecosystems, arsenic (As) and total mercury (T-Hg) represent two of the major pollutants, particularly in fish due to their ecology and the affinity of these metal(loid)s with biological cycles. This study assessed the influence of total length, total weight, relative condition factor, and trophic levels of ten marine fish species from the Colombian Caribbean on As and T-Hg accumulation in muscle tissue, as well as the differentiation in accumulated amounts based on fish habitat type. In this context, Balistes capriscus exhibited the highest As median (7949.
View Article and Find Full Text PDFWomens Health Nurs
December 2024
College of Nursing Science, Kyung Hee University, Seoul, Korea.
Purpose: Heavy metals, which are persistent in the environment and toxic, can accumulate in the body and cause organ damage, which may further negatively affect perinatal women and their fetuses. Therefore, this systematic review was conducted to evaluate the effectiveness of dietary interventions to reduce heavy metal exposure in antepartum and postpartum women.
Methods: We searched five databases (PubMed, Embase, Scopus, Web of Science, and Cochrane Library) for randomized controlled trials that provided dietary interventions for antepartum and postpartum women.
Sci Total Environ
January 2025
ECOMARE, CESAM - Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, Estrada do Porto de Pesca Costeira, 3830-565 Gafanha da Nazaré, Portugal.
Within the UN Decade on Ecosystem Restoration (2021-2030) framework, a Nature-based Solution (NbS) using Zostera noltei transplants was tested to restore a historically contaminated intertidal area. In-situ transplantation relied on patches of seagrass and sediment from a Donor meadow and its evolution was monitored for two years. The evaluation of the transplant success encompassed the seagrass coverage area, seagrass biomass, tissue mercury (Hg) accumulation, and photosynthetic efficiency.
View Article and Find Full Text PDFSci Total Environ
January 2025
Universidade Federal do Pará, Programa de Pós-Graduação em Geologia e Geoquímica, Rua Augusto Corrêa, 1, Campus Guamá, PA 66075-110 Belém, Pará, Brazil.
The knowledge of metals concentration in upwelling areas are a concern due the higher productivity of these areas In Cabo Frio Upwelling-Downwelling System (CFUS) is high primary productivity area and has been identified as an Hg hotspot to biota in SE Brazil that has been susceptible to Hg inputs, due to growing industrialization in the region. To investigate the concentration of Hg and Se metals, as well as the trophic transfer of these metals, the present study investigated Hg and Se concentrations in 64 samples collected in net mesh of >20, >64, >150 and >300 μm, in 2012, in the region's water masses. Higher mean Hg concentrations were found in zooplankton, 0.
View Article and Find Full Text PDFEnviron Pollut
December 2024
College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China; Faculty of Architecture and Engineering, Guizhou Polytechnic of Construction, Guiyang, 551400, China.
Although the use of foliar spraying with organic matter has been extensively studied and applied to reduce heavy metals in plants, research on its application for reducing mercury (Hg) accumulation in plants, particularly the more toxic methylmercury (MeHg), remains scarce. Furthermore, previous researches on the barrier mechanisms of foliar spraying primarily concentrated on the effects of spraying agents on plant physiological and biochemical indicators, with limited focus on their impacts on soil environment. Herein, the dynamic effects and mechanisms of organic foliar spraying materials, including earthworm liquid fertilizer (ELF), Tween 80 (T80), and citric acid (CA), on soil Hg methylation and accumulation in lettuce were investigated using pot experiment.
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