Rapid Monitoring of Mercury in Air from an Organic Chemical Factory in China Using a Portable Mercury Analyzer

A chemical factory, using a production technology of acetaldehyde with mercury catalysis, was located southeast of Qingzhen City in Guizhou Province, China. Previous research showed heavy mercury pollution through an extensive downstream area. A current investigation of the mercury distribution in ambient air, soils, and plants suggests that mobile mercury species in soils created elevated mercury concentrations in ambient air and vegetation. Mercury concentrations of up to 600 ng/m3 in air over the contaminated area provided evidence of the mercury transformation to volatile Hg(0). Mercury analysis of soil and plant samples demonstrated that the mercury concentrations in soil with vaporized and plant-absorbable forms were higher in the southern area, which was closer to the factory. Our results suggest that air monitoring using a portable mercury analyzer can be a convenient and useful method for the rapid detection and mapping of mercury pollution in advanced field surveys

Multi-model study of mercury dispersion in the atmosphere : Atmospheric processes and model evaluation

Current understanding of mercury (Hg) behavior in the atmosphere contains significant gaps. Some key characteristics of Hg processes, including anthropogenic and geogenic emissions, atmospheric chemistry, and air-surface exchange, are still poorly known. This study provides a complex analysis of processes governing Hg fate in the atmosphere involving both measured data from ground-based sites and simulation results from chemical transport models. A variety of long-term measurements of gaseous elemental Hg (GEM) and reactive Hg (RM) concentration as well as Hg wet deposition flux have been compiled from different global and regional monitoring networks. Four contemporary global-scale transport models for Hg were used, both in their state-of-the-art configurations and for a number of numerical experiments to evaluate particular processes. Results of the model simulations were evaluated against measurements. As follows from the analysis, the interhemispheric GEM gradient is largely formed by the prevailing spatial distribution of anthropogenic emissions in the Northern Hemisphere. The contributions of natural and secondary emissions enhance the south-to-north gradient, but their effect is less significant. Atmospheric chemistry has a limited effect on the spatial distribution and temporal variation of GEM concentration in surface air. In contrast, RM air concentration and wet deposition are largely defined by oxidation chemistry. The Br oxidation mechanism can reproduce successfully the observed seasonal variation of the RM=GEM ratio in the near-surface layer, but it predicts a wet deposition maximum in spring instead of in summer as observed at monitoring sites in North America and Europe. Model runs with OH chemistry correctly simulate both the periods of maximum and minimum values and the amplitude of observed seasonal variation but shift the maximum RM=GEM ratios from spring to summer. O3 chemistry does not predict significant seasonal variation of Hg oxidation. Hence, the performance of the Hg oxidation mechanisms under study differs in the extent to which they can reproduce the various observed parameters. This variation implies possibility of more complex chemistry and multiple Hg oxidation pathways occurring concurrently in various parts of the atmosphere

Mercury in gas and oil deposits: corrosion problem

Mercury naturally occurs in gas and oil deposits in a wide range of concentrations covering six orders of magnitude: up to 5 mg/m3 in natural gas and up to 600 ppm (mg/kg) in crude oil. Mercury in hydrocarbons poses a number of technological and environmental problems: contamination of equipment and products with this extremely toxic element, poisoning of catalysts, and initiates intensive corrosion of technological equipment, thereby enhancing accident risk. Metal mercury causes rapid electrochemical corrosion of aluminum alloys (e.g., heat exchangers) and liquid metal embrittlement (LME) of steel leading to heavy accidents. The novel technology based on Zeeman atomic absorption spectroscopy enables rapid selective mercury determination in crude oil, gas condensate, naphtha and natural gas. Examples of the technology application for gas, oil and oil products are presented

Rapid thermoscanning technique for direct analysis of mercury species in contaminated sediments: From pure compounds to real sample application

Mercury (Hg) in aquatic environments accumulates in sediments in several chemical forms, both inorganic and organic, which are often determined through time-consuming selective and sequential extraction procedures. Thermal desorption technique (pyrolysis) coupled with continuous determination by atomic absorption spectrometry (AAS) may be an easy-to-use alternative technique for the rapid identification and quantification of Hg species in the solid matrix. This technique is based on the gradual heating of a sample that releases Hg at different temperature intervals depending on its chemical form. Thus, a single Hg species that desorbs at a specific temperature may be identified via a thermogram of the sample. In this work, several commercial pure Hg compounds, natural Hg mineral species (red cinnabar, α-HgS) and one compound synthesised in the lab (α-FeOOH–––Hg) were mixed with synthetic calcium carbonate (CaCO3), silica (SiO2) and natural matrices (silicate and carbonate marine sediments) which were then desorbed in order to determine the desorption peak temperatures corresponding to each Hg species. Moreover, possible interference caused by the matrix was also considered. The results obtained from 52 desorbed MIX samples displayed different desorption temperatures for the same Hg species depending on the matrix used. Indeed, Hg species mixed with synthetic SiO2 desorbed at a temperature lower than the same species mixed with synthetic CaCO3 with a difference of approximately 100 ◦C. The analytical approach was applied to selected coastal sediments from the Gulf of Trieste (Northern Adriatic Sea, Italy), contaminated by Hg from the five centuries of cinnabar (α-HgS) mining activity from Idrija (Slovenia), in order to identify the unknown Hg species. The results revealed the presence of two peaks with a distinct temperature of desorption (~250 and 350 ◦C). The highest temperature corresponds to the mostly refractory red cinnabar (α-HgS) compound, whereas the lowest temperature is related to other species (e.g. β-HgS) that may also include Hg associated with more mobile and potentially bio-accessible species (e.g. α-FeOOH–––Hg) if compared to α-HgS. This methodological approach is a rapid and cost-effective technique useful to preliminarily quantify more stable Hg species (mainly α-HgS), underlining the relevance in considering the chemical form of the element rather than merely the total concentration for simplifying the environmental management of Hg-contaminated sediments

Five-year records of mercury wet deposition flux at GMOS sites in the Northern and Southern hemispheres

The atmospheric deposition of mercury (Hg) occurs via several mechanisms, including dry and wet scavenging by precipitation events. In an effort to understand the atmospheric cycling and seasonal depositional characteristics of Hg, wet deposition samples were collected for approximately 5 years at 17 selected GMOS monitoring sites located in the Northern and Southern hemispheres in the frameworkof the Global Mercury Observation System (GMOS) project. Total mercury (THg) exhibited annual and seasonal patterns in Hg wet deposition samples. Interannual differences in total wet deposition are mostly linked with precipitation volume, with the greatest deposition flux occurring in the wettest years. This data set provides a new insight into baseline concentrations of THg concentrations in precipitation worldwide, particularly in regions such as the Southern Hemisphere and tropical areas where wet deposition as well as atmospheric Hg species were not investigated before, opening the way for future and additional simultaneous measurements across the GMOS network as well as new findings in future modeling studies.JRC.D.2-Water and Marine Resource

Five-year records of Total Mercury Deposition flux at GMOS sites in the Northern and Southern Hemispheres

The atmospheric deposition of mercury (Hg) occurs via several mechanisms including dry and wet scavenging by precipitation events. In an effort to understand the atmospheric cycling and seasonal depositional characteristics of Hg, wet deposition samples were collected for approximately five years at 17 selected GMOS monitoring sites located in the Northern and Southern Hemispheres in the framework of the Global Mercury Observation System (GMOS) project. Total mercury (THg) exhibited annual and seasonal patterns in Hg wet deposition samples. Inter-annual differences in total wet deposition are mostly linked with precipitation volume, with the greatest deposition flux occurring in the wettest years. This data set provides a new insight into baseline concentrations of THg concentrations in precipitation worldwide, particularly in regions, such as the Southern Hemisphere and tropical areas where wet deposition as well as atmospheric Hg species were not investigated before, opening the way for future and additional simultaneous measurements across the GMOS network as well as new findings in future modeling studies.Fil: Sprovieri, Francesca. Institute of Atmospheric Pollution Research; ItaliaFil: Pirrone, Nicola. Institute of Atmospheric Pollution Research; ItaliaFil: Bencardino, Mariantonia. Institute of Atmospheric Pollution Research; ItaliaFil: D´Amore, Francesco. Institute of Atmospheric Pollution Research; ItaliaFil: Angot, Helene. Universite Joseph Fourier. Observatoire de Grenoble; FranciaFil: Barbante, Carlo. University Ca’ Foscari of Venice; Italia. Consiglio Nazionale delle Ricerche; ItaliaFil: Brunke, Ernst Günther. South African Weather Service; SudáfricaFil: Arcega Cabrera, Flor. Universidad Nacional Autónoma de México; MéxicoFil: Cairns, Warren. Institute for the Dynamics of Environmental Processes; ItaliaFil: Comero, Sara. Joint Research Centre; ItaliaFil: Dieguez, Maria del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Dommergue, Aurélien. Universite Joseph Fourier. Observatoire de Grenoble; FranciaFil: Ebinghaus, Ralf. Helmholtz Zentrum Geesthacht; AlemaniaFil: Feng, Xin Bin. Chinese Academy of Sciences; República de ChinaFil: Fu, Xuewu. Chinese Academy of Sciences; República de ChinaFil: Garcia, Patricia Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Gawlik, Bernd Manfred. Joint Research Centre; ItaliaFil: Hageström, Ulla. Swedish Environmental Research Inst. Ltd.; SueciaFil: Hansson, Katarina. Swedish Environmental Research Inst. Ltd.; SueciaFil: Horvat, Milena. Jožef Stefan Institute; EsloveniaFil: Kotnik, Jose. Jožef Stefan Institute; EsloveniaFil: Labuschagne, Casper. South African Weather Service; SudáfricaFil: Magand, Olivier. Laboratoire de Glaciologie et Géophysique de l’Environnement; FranciaFil: Martin, Lynwill. South African Weather Service; SudáfricaFil: Mashyanov, Nikolay. St. Petersburg State University; RusiaFil: Mkololo, Thumeka. South African Weather Service; SudáfricaFil: Munthe, John. Swedish Environmental Research Inst. Ltd.; SueciaFil: Obolkin, Vladimir. Siberian Branch of the Russian Academy of Sciences; RusiaFil: Islas, Martha Ramirez. Instituto Nacional de Ecología y Cambio Climático; MéxicoFil: Sena, Fabrizio. Joint Research Centre; ItaliaFil: Somerset, Vernon. South African Weather Service; SudáfricaFil: Spandow, Pia. Swedish Environmental Research Inst. Ltd.; SueciaFil: Vardè, Massimiliano. Institute of Atmospheric Pollution Research; Italia. Consiglio Nazionale delle Ricerche; ItaliaFil: Walters, Chavon. South African Weather Service; SudáfricaFil: Wängberg, Ingvar. Swedish Environmental Research Institute; SueciaFil: Weigelt, Andreas. Helmholtz Zentrum Geesthacht; AlemaniaFil: Yang, Xu. Chinese Academy of Sciences; República de ChinaFil: Zhang, Hui. Chinese Academy of Sciences; República de Chin