Using passive air samplers to quantify vertical gaseous elemental mercury concentration gradients within a forest and above soil

2021 ◽  
Author(s):  
Isabel M. Quant ◽  
Michelle Feigis ◽  
Shreya Mistry ◽  
Ying Duan Lei ◽  
Carl P. J. Mitchell ◽  
...  
Keyword(s):  
Mercury Concentration ◽  
Elemental Mercury ◽  
Concentration Gradients ◽  
Gaseous Elemental Mercury

scholarly journals Can the MerPAS Passive Air Sampler Discriminate Landscape, Seasonal, and Elevation Effects on Atmospheric Mercury? A Feasibility Study in Mississippi, USA

Atmosphere ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 617 ◽  
Author(s):  
Byunggwon Jeon ◽  
James V. Cizdziel
Keyword(s):  
Temporal Trends ◽  
Elemental Mercury ◽  
Atmospheric Mercury ◽  
Concentration Gradients ◽  
Gaseous Elemental Mercury ◽  
Passive Air Sampler ◽  
Air Sampler ◽  
Direct Mercury Analyzer ◽  
Close Proximity ◽  
Mercury Analyzer

Accurately measuring gaseous elemental mercury (GEM) concentrations in the atmosphere is important to understand its sources, cycling, distribution, and temporal trends. The MerPAS passive air sampler from Tekran Inc. (Toronto, ON, Canada) captures GEM on sulfur-impregnated activated carbon after it passes through a Radeillo diffusive barrier. Because they are small, relatively low in cost, and require no power, they can be deployed at multiple locations, yielding a much greater spatial resolution, albeit at coarser temporal resolution, compared to active sampling. In this study, we used the MerPAS to measure GEM concentration gradients at a mixed hardwood forest, wetland, pond, and a mowed (grass) field, all within close proximity (<500 m) to each other. Vertical profiles (0.5, 3.0, 5.5 m) were assessed during summer and winter. The sorbent was analyzed using a direct mercury analyzer. The samplers were captured between 0.90 to 2.2 ng over 2 weeks, well above the mean blank of 0.14 ng. We observed differences between the landscapes, elevation, and seasons. Nearest to the surface, GEM concentrations were lowest in the wetland (both seasons), where there was dense vegetation, and highest in the mowed field (both seasons). Generally, GEM levels increased with the elevation above the ground, except for the forest where the trend was slightly reversed. This suggests a possible net GEM deposition from the atmosphere to surfaces for three of the four landscapes. GEM concentrations were slightly higher in the winter than the summer at 5.5 m height where air masses were unimpeded by vegetation. Overall, we conclude that the MerPAS is indeed capable of measuring GEM gradients between landscapes, elevations, and seasons, if given sufficient collection time, good analytical precision, and low blank levels.

Dynamics of gaseous elemental mercury during polar spring and winter

2020 ◽  
Author(s):  
Fidel Pankratov ◽  
Alexander Mahura ◽  
Valentin Popov ◽  
Vladimir Masloboev
Keyword(s):  
Surface Layer ◽  
Solar Activity ◽  
Solar Radiation ◽  
Solar Energy ◽  
Mercury Concentration ◽  
Elemental Mercury ◽  
Ice Cover ◽  
Photochemical Reactions ◽  
High Solar Activity ◽  
Gaseous Elemental Mercury

&lt;p&gt;&lt;strong&gt;Dynamics of gaseous elemental mercury during polar spring and winter&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Since June 2001 the long-term monitoring of the gaseous elemental mercury (thereafter, mercury) in the surface layer of the atmospheric has been conducted near the Amderma settlement (69,72&lt;sup&gt;&amp;#208;&amp;#190;&lt;/sup&gt;N; 61,62&lt;sup&gt;o&lt;/sup&gt;E; Yugor Peninsula, Russia).&lt;/p&gt;&lt;p&gt;During this monitoring, variations of the lowered mercury concentrations (&lt;1.0 ng m&lt;sup&gt;-3&lt;/sup&gt;) were observed for spring (March&amp;#8211;May) period in 2005 and 2011. For spring 2005, the intensity of the solar radiation did not affect the number of low values of mercury concentrations. With an increase of solar activity during the day there was a reverse effect: i.e. from 9 until 15 h the number of lowered values of concentration decreased. For the evening hours, the highest number of lowered concentrations and atmospheric mercury depletion events, AMDEs (12 events) were observed. For 2005, upon reaching a daily high solar activity the processes of mercury depletion were not observed. It could be because lacking of a large number of marine aerosols in the atmospheric surface layer, although the processes of photochemical reactions did not stop. For spring 2011, during increased solar activity the number of AMDEs increased to 62 events. However, there was no ice cover observed in the coastal area, and consequently, large amounts of sea aerosol could be presented in the surface layer of the atmosphere.&lt;/p&gt;&lt;p&gt;For the winter (December-January) period, the maximum number (in total, 495) of lowered values of mercury concentration and AMDEs (32 events) were recorded in 2010&amp;#8211;2011. Such situation was previously observed only in winter of 2006&amp;#8211;2007 (13 events). As there is no direct sunlight in mentioned period, the removal of mercury from the atmosphere may be caused by combination of physical and chemical processes that are not related to photochemistry. Starting mid-January, although duration of the day increases, but solar energy is not enough to activate photochemical reactions and predominant type of solar radiation is diffuse rather than direct one. However, AMDEs were still reported at that time (18 events were registered in January 2011).&lt;/p&gt;&lt;p&gt;After mid-March, the angle of sun&amp;#8217;s declination increases and the incoming solar energy is sufficient to activate photochemistry. However, during March&amp;#8211;May there was no linear relationship identified for AMDEs. The maximum number (300) of lowered values of mercury concentration and AMDEs (21 events, with duration up to 66 hours) were registered in April. Such AMDEs are connected with presence of elevated concentrations of aerosols in the absence of ice cover in the marine coastal zone. Not excluded a possibility of contribution of anthropogenic aerosols (from burning of fossil fuels) in the process of mercury deposition from the atmosphere on the underlying surface.&lt;/p&gt;

Assessing the atmosphere-surface exchange of gaseous elemental mercury using passive air samplers

2020 ◽  
Author(s):  
Meng Si ◽  
Michelle Feigis ◽  
Isabel Quant ◽  
Shreya Mistry ◽  
Melanie Snow ◽  
...  
Keyword(s):  
Time Scales ◽  
Forest Canopy ◽  
Elemental Mercury ◽  
Permafrost Degradation ◽  
Concentration Gradients ◽  
Surface Exchange ◽  
Gaseous Elemental Mercury ◽  
The Earth ◽  
Long Time ◽  
The Impact

&lt;p&gt;The specific properties of gaseous elemental mercury (GEM) allow it to undergo bidirectional exchange between the atmosphere and the Earth&amp;#8217;s surface. Determining the direction and the magnitude of GEM&amp;#8217;s atmosphere-surface flux is possible and has been accomplished using micrometeorological and chamber techniques, but (i) is complex and labor-intensive, and (ii) often only yields fluxes over relatively short time scales. A recently developed passive air sampler for GEM has the precision required for identifying and quantifying vertical concentration gradients above the Earth&amp;#8217;s surface. The feasibility and performance of this approach is currently being tested in a number of field studies aimed at the: (i) measurement of GEM concentration gradients above both mercury-contaminated and background forest soils, (ii) quantification of vertical concentration gradients on a tower through a temperate deciduous forest canopy, and (iii) measurement of mercury concentration gradients over stable and thawing permafrost to determine the effect of permafrost degradation on GEM evasion. Contrasting with earlier flux studies, these investigations cover long time periods (up to 1.5 years) and have coarse temporal resolution (monthly to seasonally). Significant gradients of GEM air concentrations, both increasing and decreasing with height above ground, were observed, implying that at a minimum, the method is able to identify the flux direction of GEM. Under the right circumstances, this method can also be used to estimate the approximate magnitude of the GEM air-surface exchange flux. The measured gradients also reveal the impact of factors such as temperature, solar irradiance, and snow cover on air-surface exchange. The method holds promise for establishing the direction and size of exchange fluxes at long time scales of months to a year, especially in study areas where access, effort and cost are prohibitive to longer duration studies with existing approaches.&lt;/p&gt;

scholarly journals Measurement of Gaseous Elemental Mercury Concentration by Passive Sampler

2017 ◽  
Vol 46 (4) ◽  
pp. 208-214
Author(s):  
Toshihiko MATSUI ◽  
Nobuaki HARAI ◽  
Katsumi SAITOH ◽  
Koyomi NAKAZAWA ◽  
Osamu NAGAFUCHI
Keyword(s):  
Mercury Concentration ◽  
Elemental Mercury ◽  
Passive Sampler ◽  
Gaseous Elemental Mercury

scholarly journals Gaseous elemental mercury concentration in atmosphere at urban and remote sites in China

2007 ◽  
Vol 19 (2) ◽  
pp. 176-180 ◽  
Author(s):  
Zhang-wei WANG ◽  
Zuo-shuai CHEN ◽  
Ning DUAN ◽  
Xiao-shan ZHANG
Keyword(s):  
Mercury Concentration ◽  
Elemental Mercury ◽  
Gaseous Elemental Mercury ◽  
Remote Sites

Oxidation Removal of Elemental Mercury from Flue Gas by K2S2O8

2012 ◽  
Vol 209-211 ◽  
pp. 1549-1552
Author(s):  
Sheng Yu Liu ◽  
Ping Liu ◽  
Li Chao Nengzi ◽  
Wei Qiu ◽  
Cheng Wei Lu
Keyword(s):  
Mercury Concentration ◽  
Flue Gas ◽  
Removal Rate ◽  
Elemental Mercury ◽  
Chemical Form ◽  
Water Soluble ◽  
Mercury Removal ◽  
Reaction Velocity ◽  
Gaseous Elemental Mercury ◽  
Wet Scrubber

The important step for increasing gaseous elemental mercury (Hg0) removal in wet scrubber systems is altering the chemical form of the Hg0to a water-soluble oxidized species. This work focuses on the removal of elemental mercury from simulated flue gas by aqueous K2S2O8in a bubble reactor. In the system of K2S2O8oxidize Hg0, the reaction velocity of K2S2O8and Hg0is soon. Reached a higher removal rate after 10min. Increase the concentration of K2S2O8can remarkably improve the removal rate of Hg0to 85% With the rise of import mercury concentration has increased mercury removal rate to 89.5%.

scholarly journals Air Concentrations of Gaseous Elemental Mercury and Vegetation–Air Fluxes within Saltmarshes of the Tagus Estuary, Portugal

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 228
Author(s):  
Rute Cesário ◽  
Nelson J. O’Driscoll ◽  
Sara Justino ◽  
Claire E. Wilson ◽  
Carlos E. Monteiro ◽  
...  
Keyword(s):  
Leaf Area ◽  
Elemental Mercury ◽  
Ambient Air ◽  
Tagus Estuary ◽  
Contaminated Site ◽  
Gaseous Elemental Mercury ◽  
Mercury Flux ◽  
Sarcocornia Fruticosa ◽  
Air Concentrations

In situ air concentrations of gaseous elemental mercury (Hg(0)) and vegetation–atmosphere fluxes were quantified in both high (Cala Norte, CN) and low-to-moderate (Alcochete, ALC) Hg-contaminated saltmarsh areas of the Tagus estuary colonized by plant species Halimione portulacoides (Hp) and Sarcocornia fruticosa (Sf). Atmospheric Hg(0) ranged between 1.08–18.15 ng m−3 in CN and 1.18–3.53 ng m−3 in ALC. In CN, most of the high Hg(0) levels occurred during nighttime, while the opposite was observed at ALC, suggesting that photoreduction was not driving the air Hg(0) concentrations at the contaminated site. Vegetation–air Hg(0) fluxes were low in ALC and ranged from −0.76 to 1.52 ng m−2 (leaf area) h−1 for Hp and from −0.40 to 1.28 ng m−2 (leaf area) h−1 for Sf. In CN, higher Hg fluxes were observed for both plants, ranging from −9.90 to 15.45 ng m−2 (leaf area) h−1 for Hp and from −8.93 to 12.58 ng m−2 (leaf area) h−1 for Sf. Mercury flux results at CN were considered less reliable due to large and fast variations in the ambient air concentrations of Hg(0), which may have been influenced by emissions from the nearby chlor-alkali plant, or historical contamination. Improved experimental setup, the influence of high local Hg concentrations and the seasonal activity of the plants must be considered when assessing vegetation–air Hg(0) fluxes in Hg-contaminated areas.

scholarly journals An Integrated Investigation of Atmospheric Gaseous Elemental Mercury Transport and Dispersion Around a Chlor-Alkali Plant in the Ossola Valley (Italian Central Alps)

Toxics ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 172
Author(s):  
Laura Fantozzi ◽  
Nicoletta Guerrieri ◽  
Giovanni Manca ◽  
Arianna Orrù ◽  
Laura Marziali
Keyword(s):  
Elemental Mercury ◽  
Background Concentration ◽  
Dispersion Pattern ◽  
Central Alps ◽  
Gaseous Elemental Mercury ◽  
Mercury Transport ◽  
Close Proximity ◽  
Potential Impact ◽  
Hg Accumulation

We present the first assessment of atmospheric pollution by mercury (Hg) in an industrialized area located in the Ossola Valley (Italian Central Alps), in close proximity to the Toce River. The study area suffers from a level of Hg contamination due to a Hg cell chlor-alkali plant operating from 1915 to the end of 2017. We measured gaseous elemental Hg (GEM) levels by means of a portable Hg analyzer during car surveys between autumn 2018 and summer 2020. Moreover, we assessed the long-term dispersion pattern of atmospheric Hg by analyzing the total Hg concentration in samples of lichens collected in the Ossola Valley. High values of GEM concentrations (1112 ng m−3) up to three orders of magnitude higher than the typical terrestrial background concentration in the northern hemisphere were measured in the proximity of the chlor-alkali plant. Hg concentrations in lichens ranged from 142 ng g−1 at sampling sites located north of the chlor-alkali plant to 624 ng g−1 in lichens collected south of the chlor-alkali plant. A north-south gradient of Hg accumulation in lichens along the Ossola Valley channel was observed, highlighting that the area located south of the chlor-alkali plant is more exposed to the dispersion of Hg emitted into the atmosphere from the industrial site. Long-term studies on Hg emission and dispersion in the Ossola Valley are needed to better assess potential impact on ecosystems and human health.

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