Search results for "mercury"
showing 10 items of 396 documents
Effects of organic mercury on Mytilus galloprovincialis hemocyte function and morphology
2020
Abstract Filter-feeding organisms accumulate xenobiotics and other substances in their tissues. They can be useful as sentinel organisms in biomonitoring of the marine compartment. Bivalve cellular immunity is ensured by phagocytosis and cytotoxic reactions carried out by hemocytes in a network with humoral responses. These can be affected by chemical contaminants in water that can be immunosuppressors also at a low concentration increasing the sensibility to pathogens. This work is an attempt to individuate cellular markers for pollution detection, investigating the effect of methylmercury (CH3HgCl) at different concentrations on the activity and hemocyte morphology of the Mediterranean m…
The ascidian Styela plicata hemocytes as a potential biomarker of marine pollution: In vitro effects of seawater and organic mercury.
2017
Toxic metals, such as mercury, contribute substantially to anthropogenic pollution in many estuarine environments. Animals living in those environments, particularly invertebrate filter feeders like tunicates, can be used as bioindicators. In an attempt to identify cellular markers for revealing pollution, this study examined in vitro the effects of different concentrations of methyl mercury on Styela plicata hemocytes. The harvested hemocytes from S. plicata that were exposed to the metal had a significant mortality, cellular count and morphometric alterations. These findings provided evidence of MeHg immunotoxic effects on S. plicata, resulting in hemocyte death and morphological changes …
Assessing the effect of mercury pollution on cultured benthic foraminifera community using morphological and eDNA metabarcoding approaches
2018
Mercury (Hg) is a highly toxic element for living organisms and is known to bioaccumulate and biomagnify. Here, we analyze the response of benthic foraminifera communities cultured in mesocosm and exposed to different concentrations of Hg. Standard morphological analyses and environmental DNA metabarcoding show evidence that Hg pollution has detrimental effects on benthic foraminifera. The molecular analysis provides a more complete view of foraminiferal communities including the soft-walled single-chambered monothalamiids and small-sized hard-shelled rotaliids and textulariids than the morphological one. Among these taxa that are typically overlooked in morphological studies we found poten…
Exposure to Toxic Heavy Metals Can Influence Homocysteine Metabolism?
2019
Background: Homocysteine is a sulfur amino acid whose metabolism is activated in two pathways: remethylation to methionine, which requires folate and vitamin B12, and transsulfuration to cystathionine, which needs pyridoxal-5’-phosphate. High homocysteine level increases the risk of developing heart disease, stroke, peripheral vascular diseases, and cognitive impairment. Some evidence showed that exposure to these metals increased plasma homocysteine levels. Methods: A systematic review was carried out to clarify the relationship between homocysteine blood levels and exposure to toxic heavy metals (Lead, Cadmium, Mercury, and Chromium). Results: The results of this systematic review i…
Mercury, lead and cadmium concentrations in Talpa occidentalis and in their digeneans of the genus Ityogonimus
2019
Many parasites living in aquatic ecosystems are useful indicators of environmental health. On the other hand, information is scarcer with respect to the use of helminth parasites of vertebrates living in terrestrial ecosystems as monitoring tools for toxic element environmental pollution. The present study evaluates the suitability of the model Talpa occidentalis/Ityogonimus spp. as a bioindicator system for mercury (Hg), lead (Pb) and cadmium (Cd) contamination in agricultural soils from Asturias (Spain). Kidney and liver samples collected from T. occidentalis specimens (n = 36) and Ityogonimus spp. samples collected from 14 infected hosts were analyzed by ICP-MS. The highest mean levels o…
Determination of mercury at picogram level in natural waters with inductively coupled plasma mass spectrometry by using 3D printed metal scavengers
2019
The determination of ultra-trace concentrations of Hg in natural water samples via preconcentration using 3D printed metal scavenger technique followed by inductively coupled plasma mass spectrometry (ICP-MS) was developed. The determination of Hg in certified reference material ERM-CA615 (groundwater) was performed with high accuracy and precision resulting in recovery of 100 ± 3% and RSD <2.5%, respectively. Selective laser sintering (SLS) 3D printing was used to fabricate the scavengers using a mixture of polyamide-12 powder with thiol-functionalized silica. The preconcentration procedure is based on the adsorption of Hg on the scavenger and followed by elution of the preconcentrated Hg …
A dual channel sulphur-containing a macrocycle functionalised BODIPY probe for the detection of Hg(II) in a mixed aqueous solution
2018
We report herein the synthesis and chromo-fluorogenic behaviour of a new probe 1 containing a boron-dipirromethene (BODIPY) unit electronically connected with a dithia-dioxa-aza macrocycle. Acetonitrile and water-acetonitrile 95:5 v/v solutions of the probe showed an ICT band in the visible zone and are nearly non-emissive. When acetonitrile was used as solvent, addition of Hg(II) and trivalent metal cations induced an hypsochromic shift of the absorption band and moderate emission enhancements. A highly selective response was obtained when using competitive media such as wateracetonitrile 95:5 v/v. In this case only Hg(II) induced a hypsochromic shift of the absorption band and a marked em…
Monitoring programme on cadmium, lead and mercury in fish and seafood from Valencia, Spain: levels and estimated weekly intake.
2008
The study was carried out to determine the current levels of mercury, cadmium, and lead in fish and seafood from the market of Comunitat Valenciana, Spain. Levels of total mercury ranged from 0.02 to 3.15 mg kg⁻¹ w.w. (average = 0.073 mg kg⁻¹ w.w.). Cadmium concentrations ranged from 0.003 to 0.66 mg kg⁻¹ w.w. (average = 0.27 mg kg⁻¹ w.w.) for seafood, and between 0.003 and 0.71 mg kg⁻¹ w.w. (average = 0.01 mg kg⁻¹ w.w.) for marine fish. Concerning lead, concentrations from 0.02 to 0.36 mg kg⁻¹ w.w (average = 0.04 mg kg⁻¹ w.w.) were found in fish, and from 0.02 to 1.02 mg kg⁻¹ w.w. in seafood (average = 0.147 mg kg⁻¹ w.w.). The levels found were, in general, lower than maximum levels propos…
Biomonitoring of mercury in hair of breastfeeding mothers living in the Valencian Region (Spain). Levels and predictors of exposure
2017
This study focused on the evaluation of the levels of total mercury in hair among 120 breastfeeding mothers aged 20 to 45-. The concentrations of Hg ranged from 0.07 to 6.87 mu g/g with a geometric mean (GM) of 1.22 mu g/g. This GM is six times higher than the average internal exposure of mothers from other 17 European countries (0.225 mu g/g). Near 70% of mothers presented levels of Hg above the USA EPA internal exposure guideline of 1 mu g/g, and 27% exceeded the EFSA health-based guidance value of 1.9 mu g/g. The multivariate regression analysis revealed that age, smoking and fish consumption (sword fish, small fat fish, small lean fish) were the major predictors of mercury in hair. (C) …
Prenatal mercury exposure in a multicenter cohort study in Spain
2011
Background: Mercury is a ubiquitous heavy metal that may negatively affect human health. It is desirable to investigate mercury exposure in vulnerable populations. Objective: To determine the concentrations of total mercury (T-Hg) in cord blood and to evaluate the role of maternal fish consumption in a Spanish mother and child cohort. Methods: A total of 1883 mother and child pairs from a population-based cohort were included between 2004 and 2008. T-Hg concentrations were measured in whole cord blood and maternal seafood consumption was ascertained by means of a food-frequency questionnaire. Linear regression was used in stratified analyses, while a joint model was adjusted using a mixed-e…