Sediment core samples were collected from the Weihe River in February and August 2013. Cores were sectioned and analyzed for total Hg (THg) and methyl mercury (MeHg). THg in sediment cores ranged from 156 to 282 ng g(-1) in February, and from 172 to 300 ng g(-1) in August. MeHg concentrations ranged from 0.80 to 3.11 ng g(-1) in both seasons. Results showed that the diffusive fluxes were up to two orders of magnitude lower than the in situ benthic fluxes. Fluxes of MeHg measured in in situ experiments in August were positively correlated with [Formula: see text] (r = 0.930). THg and MeHg release were not strongly correlated with TOC in February. Patterns of MeHg flux differed greatly depending on oxidation-reduction potential (Eh) (r > 0.70) conditions in the two seasons.
Sulfate-driven anaerobic oxidation of methane (AOM) and anaerobic digestion (AD) with municipal wastewater sludge containing heavy metals may provide favorable conditions for the biogeochemical transformation of mercury (Hg) by methanogens and methanotrophs. However, it remains largely unclear what Hg-methylators functioned and what role Methanosarcina played in these processes. Here, we performed sulfate-driven AOM following AD with Hg-containing wastewater sludge and investigated the role of microbes, especially Methanosarcina, in the biogeochemical transformation of Hg based on 16S rRNA amplicon and metatranscriptomic sequencing.
The mercury(II) halide complex [1,3-di--butyl-2,4-bis-(-butyl-amino)-1,3,2λ,4λ-di-aza-diphosphetidine-2,4-diselone-κ ,']di-iodido-mercury(II),-di-methyl-formamide monosolvate, [HgI(CHNPSe)]·CHNO or ()HgI, , containing -[( BuNH)(Se)P(μ-N Bu)P(Se)(NH Bu)] () was synthesized and structurally characterized. The crystal structure of confirms the chelation of chalcogen donors to HgI with a natural bite angle of 112.95 (2)°.
North Slope Borough, Department of Wildlife Management, Utqiaġvik, AK 99723, USA; Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99708, USA.
Ringed (Pusa hispida), bearded (Erignathus barbatus), spotted (Phoca largha), and ribbon (Histriophoca fasciata) seals are ice-associated seals that are important subsistence resources for coastal Alaska Native people. These seals are also mid- to upper trophic level Arctic predators and primary prey of polar bears (Ursus maritimus). We analyzed concentrations of 19 trace elements in seal liver, kidney, muscle, and blubber, including arsenic, cadmium, lead, mercury, and vanadium due to their potential toxicity.
Mercury (Hg) has been recognized as a global pollutant with a toxic, mobile, and persistent nature. It adversely affects the ecosystem and human health. Already developed biosensors for Hg detection majorly suffer from poor sensitivity and specificity.
Texas A&M Agriculture, Food and Nutrition Evidence Center, Fort Worth, Texas, United States; Department of Nutrition, Texas A&M University, College Station, Texas, United States.
Background: Determining dietary recommendations for seafood consumed during pregnancy, lactation, and childhood requires consideration of the known nutritional benefits and potential harm due to toxicant exposure as they relate to child outcomes.
Objectives: To describe the scope of the evidence associated with seafood-related toxicant exposure and child outcomes and to identify toxicant-outcome pairs that may have sufficient evidence to conduct a systematic review.
Methods: We included studies examining seafood toxicant exposure during pregnancy, lactation, and childhood, and child outcomes.
