The Experts below are selected from a list of 14271 Experts worldwide ranked by ideXlab platform
Douglas Freehafer - One of the best experts on this subject based on the ideXlab platform.
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Mercury in Fish from streams and rivers in New York State: Spatial patterns, temporal changes, and environmental drivers
Ecotoxicology, 2020Co-Authors: Karen Riva-murray, Wayne Richter, N. Roxanna Razavi, Douglas A. Burns, Lisa B. Cleckner, Mark Burton, Scott D. George, Douglas FreehaferAbstract:Mercury (Hg) concentrations in freshwater Fish across the state of New York frequently exceed guidelines considered harmful to humans and wildlife, but statewide distribution and temporal changes are not well known for the state’s streams and rivers. We analyzed existing data to describe recent spatial patterns, identify key environmental drivers, and assess temporal changes. Size classes within sportFishes and prey Fishes formed ‘functional taxa’ (FT), and standardized scores were generated from 2007–2016 data for 218 sites. Muscle Hg in ≥1 sportFish FT exceeded human-health guidelines of 50 ng/g (sensitive populations) and 300 ng/g (general population, GP) at 93 and 56% of sites, respectively, but exceeded 1000 ng/g (a state threshold) at only 10% of sites. Whole-body Hg in ≥1 prey Fish FT exceeded wildlife thresholds of 40 ng/g and 100 ng/g at 91 and 51% of sites, respectively. Environmental drivers of recent spatial patterns include extent of forest cover and storage, the latter an indicator of wetlands. Standardized Hg scores increased with increasing atmospheric Hg deposition and storage across rural ‘upland’ regions of New York. However, scores were not related to atmospheric deposition in more-developed ‘lowland’ regions due to the limited methylation potential of urban landscapes. Comparisons of 2010–2015 sportFish Hg concentrations with those of 1998 and 2000–2005 showed inconsistent temporal changes both among and within eight sites examined. Some recent stream and river Fish Hg spatial patterns differed from those of lake-based studies, highlighting the importance of New York’s flowing waters to future Hg monitoring and risk assessment.
M Mascini - One of the best experts on this subject based on the ideXlab platform.
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an optimized digestion method coupled to electrochemical sensor for the determination of cd cu pb and hg in Fish by square wave anodic stripping voltammetry
Talanta, 2009Co-Authors: Valentina Meucci, Serena Laschi, Maria Minunni, Carlo Pretti, Luigi Intorre, G Soldani, M MasciniAbstract:An optimized digestion method coupled to electrochemical detection to monitor lead, copper, cadmium and Mercury in Fish tissues was developed. Square wave anodic stripping voltammetry (SWASV) coupled to disposable screen-printed electrodes (SPEs) was employed as fast and sensitive electroanalytical method for heavy metals detection. Different approaches in digestion protocols were assessed. The study was focused on Atlantic hake fillets because of their wide diffusion in the human nutrition. Best results were obtained by digesting Fish tissue with hydrogen peroxide/hydrochloric acid mixture coupled to solid phase (SP) purification of the digested material. This combined treatment allowed quantitative extraction from Fish tissue (muscle) of the target analytes, with fast execution times, high sensitivity and avoiding organic residues eventually affecting electrochemical measurements. Finally, the method has been validated with reference standard materials such as dogFish muscle (DORM-2) and mussel tissues (NIST 2977).
James K. Hammitt - One of the best experts on this subject based on the ideXlab platform.
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The Welfare Value of FDA's Mercury-in-Fish Advisory: A Dynamic Reanalysis*
Journal of Health Economics, 2014Co-Authors: Christoph M. Rheinberger, James K. HammittAbstract:Assessing the welfare impact of consumer health advisories is a thorny task. Recently, Shimshack and Ward (2010) studied how U.S. households responded to FDA's 2001 Mercury-in-Fish advisory. They found that the average at-risk household reduced Fish consumption by 21%, resulting in a 17%-reduction in Mercury exposure at the cost of a 21%-reduction in cardioprotective omega-3 fatty acids. Based on a static assessment of the health costs and benefits Shimshack and Ward concluded that the advisory policy resulted in an overall consumer welfare loss. in this note, we propose a dynamic assessment that links the long-term cardiovascular health effects of the advisory to life-cycle consumption. We find that under reasonable assumptions the welfare loss might be much larger than suggested. Our analysis highlights the importance of accounting for dynamic effects when evaluating persistent changes in exposure to environmental health risks.
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The welfare value of FDA’s Mercury-in-Fish advisory: A dynamic reanalysis
Journal of Health Economics, 2014Co-Authors: Christoph M. Rheinberger, James K. HammittAbstract:Assessing the welfare impact of consumer health advisories is a thorny task. Recently, Shimshack and Ward (2010) studied how U.S. households responded to FDA’s 2001 Mercury-in-Fish advisory. They found that the average at-risk household reduced Fish consumption by 21%, resulting in a 17%-reduction in Mercury exposure at the cost of a 21%-reduction in cardioprotective omega-3 fatty acids. Based on a static assessment of the health costs and benefits Shimshack and Ward concluded that the advisory policy resulted in an overall consumer welfare loss. in this note, we propose a dynamic assessment that links the long-term cardiovascular health effects of the advisory to life-cycle consumption. We find that under reasonable assumptions the welfare loss might be much larger than suggested. Our analysis highlights the importance of accounting for dynamic effects when evaluating persistent changes in exposure to environmental health risks.
Liping Yu - One of the best experts on this subject based on the ideXlab platform.
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cloud point extraction preconcentration prior to high performance liquid chromatography coupled with cold vapor generation atomic fluorescence spectrometry for speciation analysis of Mercury in Fish samples
Journal of Agricultural and Food Chemistry, 2005Co-Authors: Liping YuAbstract:A cloud point extraction methodology was developed for simultaneous preconcentration of Hg(II), methylMercury (MeHg), ethylMercury (EtHg), and phenylMercury (PhHg) prior to reversed-phase high-performance liquid chromatography (HPLC) on-line coupled with cold vapor atomic fluorescence spectrometry for speciation analysis of Mercury in Fish. The four Mercury species were taken into complexes with ammonium pyrrolidine dithiocarbamate (APDC) in aqueous nonionic surfactant Triton X-114 medium and concentrated in the surfactant-rich phase by bringing the solution to the temperature of 40 °C. Baseline separation of the enriched complexes was achieved on an RP-C18 column with a mixture of methanol, acetonitrile, and water (65:15:20, v/v) containing 200 mmol L-1 HAc (pH 3.5) as the mobile phase. An on-line postcolumn oxidation of the effluent from HPLC, in the presence of K2S2O8 in HCl, was applied in the system followed by an optimal cold vapor generation of Mercury species. The variables affecting the complexat...
Mercedes Sánchez - One of the best experts on this subject based on the ideXlab platform.
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Microwave dissolution for the determination of Mercury in Fish by cold vapour atomic absorption spectrometry
Analytica Chimica Acta, 1992Co-Authors: Miguel Navarro, María Del Carmen López López, H. López, Mercedes SánchezAbstract:Abstract A procedure is described for the determination in Fish species from the Mediterranean Spanish coast by cold vapour atomic absorption spectrometry. The samples were decomposed with nitric acid in a microwave acid digestion bomb. A certified reference sample was analysed and the results obtained agreed well with the certified values. The limit of detection for the samples investigated was 0.195 ng ml −1 . The concentrations of Mercury in Fish ranged from 0.033 to 1.211 μg g −1 .