Element content and daily intake from dietary supplements (nutraceuticals) based on algae, garlic, yeast fish and krill oils—Should consumers be worried?

The authors would like to thank Agilent Technologies for the loan of the 8800 ICP-QQQ used in this study. Michael Stiboller thanks European Union’s Lifelong Learning Programme ‘Leonardo da Vinci’: “ALUMNI UNI GRAZ MOBILITY PROGRAMME 2013-2015” for financial support of his placement.Peer reviewedPostprin

Hg speciation in petroleum hydrocarbons with emphasis on the reactivity of Hg particles

Acknowledgment Mohammed M. Lawan, David J. Bellis, Andrea Raab, and Dagmar S. Urgast are thanked for all of their advice on ICP-MS, which has helped to achieve this work. Graeme Nicol is thanked for his help with ultracentrifuge. John Alvarez, Dennis O’Rear, and Sheila Yeh (Chevron, ETC, U.S.) are acknowledged for their valuable comments and fruitful discussion. Z.G. thanks Chevron, U.S., and the College of Physical Sciences at University of Aberdeen for the provided studentship.Peer reviewedPostprin

Reactive gaseous mercury is generated from chloralkali factories resulting in extreme concentrations of mercury in hair of workers

Part of this research was undertaken on the XAS and XFM beamlines at the Australian Synchrotron, Victoria, Australia. The authors thank UNEP Chemicals for financial support of this study as part of the project: Management of Mercury and Mercury containing waste.Peer reviewedPublisher PD

In vivo formation of natural HgSe nanoparticles in the liver and brain of pilot whales

Acknowledgments Z.G. thanks to the College of Physical Sciences at University of Aberdeen and Chevron USA for the provided studentship. P.M.K. is the recipient of an Australian Research Council Future Fellowship (FT120100277). Parts of this research were undertaken on the XFM beamline at the Australian Synchrotron, Victoria, Australia. The assistance of Daryl Howard (XFM beamline, Australian Synchrotron) is acknowledged. Although EPA contributed to this article, the research presented was not performed by or funded by EPA and was not subject to EPA's quality system requirements. Consequently, the views, interpretations, and conclusions expressed in this article are solely those of the authors and do not necessarily reflect or represent EPA's views or policies. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. The authors declare no competing financial interests. F.L.R. and A.B. acknowledge Scottish Marine Animal Stranding Scheme and Marine Scotland for funding. Author Contributions E.M.K and J.F. designed the experiments. Z.G. measured total Hg and conducted Hg speciation. Total Se was determined by A.R. and Z.G. M.M.L. performed Se speciation and 2D imaging by LA-ICP-MS was done by D.S.U. XANES was performed by K.S. and XRF by E.L. and P.M.K. Samples were obtained by E.M.K. through A.B. and age determination was done by F.R. spICP-MS was performed by E.H.L., K.L., G.W. and Z.G. The manuscript was written by Z.G. and all authors discussed the results and commented on the manuscript.Peer reviewedPublisher PD

Nanoparticles as a younger member of the trace element species family - a food perspective

Speciation analysis plays a key role in understanding the biological activity and toxicity of an element. So far, classical speciation analysis focused only on the dissolved fraction of an elemental species, whereas nanoparticle forms of analytes are being widely found in consumer and industrial products. A significant contributor to human exposure to nanoparticles is through food into which nanoparticles can be incorporated from endogenous sources or they may be formed naturally in the living organisms. Nanoparticles often undergo changes in the food matrices and upon consumption, in the gastrointestinal tract, which present a significant challenge to their characterisation. Therefore, a combination of both classical and nanoparticle speciation analytical techniques is needed for the characterisation of both dissolved and particulate forms of the chemical species. This article presents and discusses the current trends in analysis of nanoparticle behaviour in the gastrointestinal tract and formation and characterisation of biogenic nanoparticles

The role of selenium in mercury toxicity – current analytical techniques and future trends in analysis of selenium and mercury interactions in biological matrices

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Mercury Speciation and Distribution in an Egyptian Natural Gas Processing Plant

Mohamed F. Ezzeldin is very grateful for the financial support provided by the Ministry of Higher Education and Scientific Research (Egypt), for providing the samples and all logistics by the Ministry of Petroleum and Mineral Resources (Egypt) and the University of Aberdeen (UK) is also acknowledged for the support of this PhD project.Peer reviewedPostprintPostprin

Hg Speciation in Petroleum Hydrocarbons with Emphasis on the Reactivity of Hg Particles

Particulate HgS is generally thought to be the most abundant Hg species in stored petroleum hydrocarbons stocked on-shore. It is also assumed that due to its high stability constant, HgS is chemically inert. However, results from the current study would suggest otherwise. First, a comparison study of the analytical performance of ICP-MS and CV-AFS with respect to matrix effects showed no significant difference in the measured Hg concentrations in studied samples when CV-AFS is used in the alkali mode. Subsequently, the suitability of three quantification methods during Hg speciation was investigated. Both external calibration and standard addition methods proved troublesome with the former showing matrix dependence and the latter being hindered by the formation of an emulsion during the derivatization step. Results from species-specific isotope dilution (SS-ID-GC-ICP-MS), on the other hand, obtained at different equilibration times, showed a random variation in the calculated Hg²⁺ concentration (RSD 32%), suggesting that factors independent of equilibration time cause the observed variation. Further sedimentation of Hg particulate by means of ultracentrifugation improved the precision of SS-ID-GC-ICP-MS by 10-fold. These results would suggest that Hg particles in petroleum products are reactive at low temperature during Grignard alkylation

Mercury Speciation and Distribution in an Egyptian Natural Gas Processing Plant

Unprocessed petroleum hydrocarbons often contain high concentrations of mercury (Hg), which can severely damage the metal components of a processing plant and pose a health risk to the workers and the natural environment. Although Hg removal units can significantly reduce the Hg concentration in the export products, they are often installed in the final stage of the processing plant, thus failing to protect the production facilities. In this study, Hg distribution within a natural gas processing plant was studied to identify the most effective place for a Hg removal unit. Additionally, the impact of sampling container materials and their acidification was evaluated, and Hg species in the condensate were quantified. Total Hg concentration was significantly higher in all samples stored in glass in comparison to that with plastic containers. However, the acidification effect of the containers was more pronounced for Hg in nonpolar solutions. Interestingly, the assessment of Hg distribution within the gas plant showed that the export gas is being enriched in Hg, whose concentration rose from 1.25 to 4.11 μg/Sm³ during the processing steps. The second stage separator was identified as the source of excess Hg, which partitioned from the liquid phase of condensate to the gas phase as a result of reduced operational pressure and temperature. The dominant Hg species found in the analyzed gas condensates were elemental Hg (Hg⁰) and inorganic Hg with the methylmercury fraction comprising up to 18%. However, it was also found that the % fraction of individual Hg species varied along the plant units most likely as a result of Hg⁰ migration to the export gas. Therefore, to protect all treatment facilities from Hg contamination, the Hg removal unit should be installed after the second stage compressor

Possible link between Hg and Cd accumulation in the brain of long-finned pilot whales (Globicephala melas)

Acknowledgements M. M. Lawan for his helpful discussions about Se and advice on ICP-MS. C. C. Brombach for his introduction to CV-AFS and to D. Bellis for valuable comments and reviewing the English language in the manuscript. ZG would also like to thank the College of Physical Sciences at the University of Aberdeen and Chevron USA for the provided studentship. FLR and AB acknowledge Scottish Marine Animal Stranding Scheme and Marine Scotland for the funding.Peer reviewedPostprin