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1

Mercury baseline levels in Flemish soils (Belgium)  

Microsoft Academic Search

It is important to establish contaminant levels that are normally present in soils to provide baseline data for pollution studies. Mercury is a toxic element of concern. This study was aimed at assessing baseline mercury levels in soils in Flanders. In a previous study, mercury contents in soils in Oost-Vlaanderen were found to be significantly above levels reported elsewhere. For

Filip M. G. Tack; Thomas Vanhaesebroeck; Marc G. Verloo; Kurt Van Rompaey; Eric Van Ranst

2005-01-01

2

Investigation of mercury levels in soil around a municipal solid waste incinerator in Shenzhen, China  

Microsoft Academic Search

Within the management hierarchy of municipal solid waste (MSW), incineration with energy recovery is a desired and viable\\u000a option often used in densely populated and economically developed cities. The gaseous and particulate mercury (Hg) emitted\\u000a from MSW incinerators may accumulate in the soil entering via dry and wet deposition. To investigate the soil Hg level and\\u000a estimate the effects of

Jun-Jian Wang; Hong-Wei Zhao; Xiu-Ping Zhong; Si-Fang Kong; Yang-Sheng Liu; Hui Zeng

3

Bioavailability and stability of mercury sulfide in Armuchee (USA) soil  

SciTech Connect

Because of the adverse effects of elemental mercury and mercury compounds upon human health, the U.S. Department of Energy (DOE) is engaged in an on-going effort to monitor and remediate mercury-contaminated DOE sites. In order to more cost effectively implement those extensive remediation efforts, it is necessary to obtain an improved understanding of the role that mercury and mercury compounds play in the ecosystem. We have conducted pilot scale experiments to study the bioavailability of mercury sulfide in an Armuchee (eastern US ) soil. The effects of plants and incubation time on chemical stability and bioavailability of HgS under simulated conditions of the ecosystem have been examined, as has the dynamics of the dissolution of mercury sulfide by various extractants. The results show that mercury sulfide in contaminated Armuchee soil was still to some extent bioavailable to plants. After planting, soil mercury sulfide is more easily dissolved by both 4 M and 12 M nitric acid than pure mercury sulfide reagent. Dissolution kinetics of soil mercury sulfide and pure chemical reagent by nitric acid are different. Mercury release by EDTA from HgS-contaminated soil increased with time of reaction and soil mercury level. Chelating chemicals increase the solubility and bioavailability of mercury in HgS-contaminated soil. (authors)

Han, Fengxiang; Shiyab, Safwan; Su, Yi; Monts, David L.; Waggoner, Charles A. [Institute for Clean Energy Technology (ICET ), Mississippi State University, 205 Research Blvd. Starkville, MS 39759 (United States); Matta, Frank B. [Department of Plant and Soil Sciences, Mississippi State University, MS 39762 (United States)

2007-07-01

4

Mercury content of Illinois soils  

USGS Publications Warehouse

For a survey of Illinois soils, 101 cores had been collected and analyzed to determine the current and background elemental compositions of Illinois soils. Mercury and other elements were determined in six samples per core, including a surface sample from each core. The mean mercury content in the surface samples was 33 ?? 20 ??g/kg soil, and the background content was 20 ?? 9 ??g/kg. The most probable sources of mercury in these soils were the parent material, and wet and dry deposition of Hg0 and Hg2+ derived from coal-burning power plants, other industrial plants, and medical and municipal waste incinerators. Mercury-bearing sewage sludge or other fertilizers applied to agricultural fields could have been the local sources of mercury. Although the mercury content correlated with organic carbon content or clay content in individual cores, when all the data were considered, there was no strong correlation between mercury and either the organic carbon or the clay-size content.

Dreher, G.B.; Follmer, L.R.

2004-01-01

5

Assessment of Mercury Levels in Soils, Waters, Bottom Sediments and Fishes of Acre State in Brazilian Amazon  

Microsoft Academic Search

Mercury in the aquatic biota and geologic materials in areas without anthropogenic sources has been stimulating the discussion about the possibility of natural Hg occurrence in the Amazon region. In this study the dispersion of Hg in different geologic materials as well as its relationship with high Hg levels, detected in some species of carnivorous fish consumed in the Rio

E. S. Brabo; R. S. Angélica; A. P. Silva; K. R. F. Faial; A. F. S. Mascarenhas; E. C. O. Santos; I. M. Jesus; E. C. B. Loureiro

2003-01-01

6

OCCURRENCE OF MERCURY-RESISTANT MICROORGANISMS IN MERCURY-CONTAMINATED SOILS AND SEDIMENTS IN PAVLODAR, KAZAKHSTAN  

EPA Science Inventory

There is extensive mercury contamination of soil surrounding a chloralkali plant in Pavlodar, Kazakhstan that operated from 1970 to 1990. High-level mercury contamination exists within the confines of the plant, at nearby off-site waste storage and evaporation ponds, and in Balky...

7

OCCURRENCE OF MICROORGANISMS RESISTANT TO MERCURY IN MERCURY CONTAMINATED SOILS AND SEDIMENTS IN PAVLODAR, KAZAKHSTAN  

EPA Science Inventory

There is extensive mercury contamination of soil surrounding a chloralkali plant in Pavlodar, Kazakhstan that operated from 1970 to 1990. High-level mercury contamination exists within the confines of the plant, at nearby off-site waste storage and evaporation ponds, and in Balky...

8

ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL  

SciTech Connect

U.S. Department of Energy (DOE) used large quantities of mercury in the uranium separating process from the 1950s until the late 1980s in support of national defense. Some of this mercury, as well as other hazardous metals and radionuclides, found its way into, and under, several buildings, soil and subsurface soils and into some of the surface waters. Several of these areas may pose potential health or environmental risks and must be dealt with under current environmental regulations. DOE's National Energy Technology Laboratory (NETL) awarded a contract ''Alternative Field Methods to Treat Mercury in Soil'' to IT Group, Knoxville TN (IT) and its subcontractor NFS, Erwin, TN to identify remedial methods to clean up mercury-contaminated high-clay content soils using proven treatment chemistries. The sites of interest were the Y-12 National Security Complex located in Oak Ridge, Tennessee, the David Witherspoon properties located in Knoxville, Tennessee, and at other similarly contaminated sites. The primary laboratory-scale contract objectives were (1) to safely retrieve and test samples of contaminated soil in an approved laboratory and (2) to determine an acceptable treatment method to ensure that the mercury does not leach from the soil above regulatory levels. The leaching requirements were to meet the TC (0.2 mg/l) and UTS (0.025 mg/l) TCLP criteria. In-situ treatments were preferred to control potential mercury vapors emissions and liquid mercury spills associated with ex-situ treatments. All laboratory work was conducted in IT's and NFS laboratories. Mercury contaminated nonradioactive soil from under the Alpha 2 building in the Y-12 complex was used. This soils contained insufficient levels of leachable mercury and resulted in TCLP mercury concentrations that were similar to the applicable LDR limits. The soil was spiked at multiple levels with metallic (up to 6000 mg/l) and soluble mercury compounds (up to 500 mg/kg) to simulate expected ranges of mercury contamination and to increase the TCLP mercury values. IT/NFS investigated ambient temperature amalgamation/stabilization/fixation of mercury-contaminated soils to meet these objectives. Treatment ranged in size from a few ounces to 10 pounds. The treatability study philosophy was to develop working envelops of formulations where reasonable minimum and maximum amounts of each reagent that would successfully treat the contaminated soil were determined. The dosages investigated were based on ratios of stoichiometric reactions and applications of standard sets of formulations. The approach purposely identified formulations that failed short or longer cure-time performance criteria to define the limits of the envelope. Reagent envelops successfully met the project requirements one day after treatment and after greater than 30-day cures. The use of multiple levels of spikes allowed the establishment of reagent dosages that were successful across a broad range of mercury values, e.g., 50 to 6000 mg/kg mercury. The treatment products were damp to slightly wet material. Enough drying reagent, e.g., Portland cement or lime by-product, were added to some formulations to control the leachability of uranium and other hazardous metals and to ensure the product passed the paint filter test. Cost analyzes and conceptual designs for four alternatives for full-scale treatments were prepared. The alternatives included two in-situ treatments and two ex-situ treatments. The cost estimates were based on the results from the bench-scale study. All four alternatives treatment costs were well below the baseline costs.

Ernest F. Stine Jr; Steven T. Downey

2002-08-14

9

MERCURY RELEASE FROM DISTURBED ANOXIC SOILS  

SciTech Connect

The primary objectives of experiments conducted at the Energy & Environmental Research Center (EERC) were to provide information on the secondary release of mercury from contaminated anoxic sediments to an aqueous environment after disturbance/change of in situ physical conditions and to evaluate its migration and partitioning under controlled conditions, including implications of these processes for treatment of contaminated soils. Experimental work included (1) characterization of the mercury-contaminated sediment; (2) field bench-scale dredging simulation; (3) laboratory column study to evaluate a longer-term response to sediment disturbance; (4) mercury volatilization from sediment during controlled drying; (5) resaturation experiments to evaluate the potential for secondary release of residual mercury after disturbance, transport, drying, and resaturation, which simulate a typical scenario during soil excavation and transport to waste disposal facilities; and (6) mercury speciation and potential for methylation during column incubation experiments.

Jaroslav Solc; Bethany A. Bolles

2001-07-16

10

Mercury Levels in Infants Receiving Routine Immunizations  

MedlinePLUS

... Skip Content Marketing Share this: Main Content Area Mercury Levels in Infants Receiving Routine Immunizations Study I: Infant Metabolism of Thimerosal versus Methyl Mercury NIAID-supported studies at the University of Rochester ...

11

ABIOLOGICAL METHYLATION OF MERCURY IN SOIL  

EPA Science Inventory

This work defines several factors influencing the methylation of mercuric ion in soil. Two of the most important findings were that it is possible to extract the mercury methylating factor from soil with a solution of 0.5N sodium hydroxide and that this factor is responsible for ...

12

ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL  

SciTech Connect

The Department of Energy (DOE) currently has mercury (Hg) contaminated materials and soils at the various sites. Figure 1-1 (from http://www.ct.ornl.gov/stcg.hg/) shows the estimated distribution of mercury contaminated waste at the various DOE sites. Oak Ridge and Idaho sites have the largest deposits of contaminated materials. The majorities of these contaminated materials are soils, sludges, debris, and waste waters. This project concerns treatment of mercury contaminated soils. The technology is applicable to many DOE sites, in-particular, the Y-12 National Security Complex in Oak Ridge Tennessee and Idaho National Engineering and Environmental Laboratory (INEEL). These sites have the majority of the soils and sediments contaminated with mercury. The soils may also be contaminated with other hazardous metals and radionuclides. At the Y12 plant, the baseline treatment method for mercury contaminated soil is low temperature thermal desorption (LTTD), followed by on-site landfill disposal. LTTD is relatively expensive (estimated cost of treatment which exclude disposal cost for the collect mercury is greater than $740/per cubic yard [cy] at Y-12), does not treat any of the metal or radionuclides. DOE is seeking a less costly alternative to the baseline technology. As described in the solicitation (DE-RA-01NT41030), this project initially focused on evaluating cost-effective in-situ alternatives to stabilize or remove the mercury (Hg) contamination from high-clay content soil. It was believed that ex-situ treatment of soil contaminated with significant quantities of free-liquid mercury might pose challenges during excavation and handling. Such challenges may include controlling potential mercury vapors and containing liquid mercury beads. As described below, the focus of this project was expanded to include consideration of ex-situ treatment after award of the contract to International Technology Corporation (IT). After award of the contract, IT became part of Shaw E&I. The company will be denoted as ''IT'' for the rest of the document since the original contract was awarded to IT. This report details IT, Knoxville, TN and its subcontractor Nuclear Fuels Services (NFS) study to investigate alternative mercury treatment technology. The IT/NFS team demonstrated two processes for the amalgamation/stabilization/fixation of mercury and potentially Resource Conservation Recovery Act (RCRA) and radionuclide-contaminated soils. This project was to identify and demonstrate remedial methods to clean up mercury-contaminated soil using established treatment chemistries on soil from the Oak Ridge Reservation, Y-12 National Security Complex, the off-site David Witherspoon properties, and/or other similarly contaminated sites. Soil from the basement of Y-12 Plant Alpha 2 Building at the Oak Ridge Reservation was received at IT and NFS on December 20, 2001. Soils from the other locations were not investigated. The soil had background levels of radioactivity and had all eight RCRA metals well below the Toxicity Characteristic (TC) criteria. This project addresses the new DOE Environmental Management Thrust 2 ''Alternative Approaches to Current High Risk/High Cost Baselines''. Successful completion of this project will provide a step-change in DOE's treatment ability.

Ernie F. Stine

2002-08-14

13

Spatial distribution of mercury and arsenic levels in water, soil and cassava plants in a community with long history of gold mining in Tanzania.  

PubMed

This study examined the spatial distribution of total mercury (THg) and total arsenic (TAs) in water, soil and cassava (Manihot esculenta) (leaves and roots) samples taken from areas in Rwamagasa village in northwestern Tanzania where daily living activities occur in close proximity to extensive artisanal and small scale gold mining. Results indicated that 33.3 % of the water sources had THg levels above the WHO guideline of 1.0 µg/L for safe drinking water, and 12.5 % had TAs levels above 10 µg/L. Cassava leaves were found to have higher THg (ranging from 8.3 to 167 µg/kg) and TAs (ranging from 60 to 1,120 µg/kg) levels than cassava roots, which ranged between 1.2-8.3 µg/kg for THg and 25-310 µg/kg for TAs. Concentrations of THg and TAs in soil samples ranged between 5.8-1,759 and 183-20,298 µg/kg, respectively. Both THg and TAs were found to be distributed throughout Rwamagasa village. PMID:24923470

Nyanza, Elias C; Dewey, Deborah; Thomas, Deborah S K; Davey, Mark; Ngallaba, Sospatro E

2014-12-01

14

FACTORS INFLUENCING THE VOLATILIZATION OF MERCURY FROM SOIL  

EPA Science Inventory

Mercury volatilization from soils amended to 1 ppm mercury with mercuric nitrate ceased within 1 week after application. During the first week, 20% of the applied mercury was lost from a silty clay-loam soil and 43% was lost from a loamy sand soil. Volatilization of Hg from the l...

15

Mercury and plants in contaminated soils. 2: Environmental and physiological factors governing mercury flux to the atmosphere  

Microsoft Academic Search

The objective of this study was to evaluate the role of physiological and environmental factors in governing the flux of elemental mercury from plants to the atmosphere. Five species (Lepidium latifolium, Artemisia douglasiana, Caulanthus sp., Fragaria vesca, and Eucalyptus globulus) with different ecological and physiological attributes and growing in soils with high levels of mercury contamination were examined. Studies were

Todd L. Leonard; M. S. Gustin; G. C. J. Fernandez; G. E. Jr. Taylor

1998-01-01

16

Mercury and plants in contaminated soils. 2: Environmental and physiological factors governing mercury flux to the atmosphere  

SciTech Connect

The objective of this study was to evaluate the role of physiological and environmental factors in governing the flux of elemental mercury from plants to the atmosphere. Five species (Lepidium latifolium, Artemisia douglasiana, Caulanthus sp., Fragaria vesca, and Eucalyptus globulus) with different ecological and physiological attributes and growing in soils with high levels of mercury contamination were examined. Studies were conducted in a whole-plant, gas-exchange chamber providing precise control of environmental conditions, and mercury flux was estimated using the mass balance approach. Mercury flux increased linearly as a function of temperature within the range of 20 to 40 C, and the mean temperature coefficient (Q{sub 10}) was 2.04. The temperature dependence of mercury flux was attributed to changes in the contaminant`s vapor pressure in the leaf interior. Mercury flux from foliage increased linearly as a function of irradiance within the range of 500 to 1,500 {micro}mol m/s, and the light enhancement of mercury flux was within a factor of 2.0 to 2.5 for all species. Even though the leaf-to-atmosphere diffusive path for mercury vapor from foliage is similar to that of water vapor, stomatal conductance played a secondary role in governing mercury flux. In a quantitative comparison with other studies in both laboratory and field settings, a strong linear relationship is evident between mercury vapor flux and the natural logarithm of soil mercury concentration, and this relationship may have predictive value in developing regional- and continental-scale mercury budgets. The most critical factors governing mercury flux from plants are mercury concentration in the soil, leaf area index, temperature, and irradiance.

Leonard, T.L.; Gustin, M.S.; Fernandez, G.C.J. [Univ. of Nevada, Reno, NV (United States); Taylor, G.E. Jr. [George Mason Univ., Fairfax, VA (United States). Dept. of Biology

1998-10-01

17

The effect of redox potential on the electrokinetic remediation of mercury contaminated soils  

SciTech Connect

An electrokinetic process for remediation of mercury contaminated soils using an iodine-iodide lixiviant was developed. In this process, reduced forms of insoluble mercury are oxidized by iodine. Iodide then reacts with mercury to form the highly soluble HgI{sub 4}{sup 2-} complex, which in turn migrates toward the anode via electromigration. The objective was to determine the thermodynamic conditions under which mercury could be solubilized and transported from the soil. At the end of the electrokinetic treatment process, pH, pE, iodine, iodide, and soluble and total mercury were measured along the length of the soil. The process was tested on a soil contaminated with HgS (cinnabar) in the laboratory and a contaminated soil obtained from a hazardous waste site. Up to 99% overall removal of mercury could be achieved from the laboratory contaminated soil. Up to 84% of mercury was removed from some sections of the field contaminated soil, but overall removal was only 6%. The presence of iodine in the soil pore water was found to be the most important factor in solubilization of mercury. Residual levels of soluble Hg remaining in soil after treatment were greater than allowed by current regulations and far in excess of the solubility of Hg compounds present in the untreated soil.

Cox, C.D.; Shoesmith, M.A.; Ghosh, M.M. [Univ. of Tennessee, Knoxville, TN (United States)

1996-12-31

18

Ammonium thiosulphate enhanced phytoextraction from mercury contaminated soil--results from a greenhouse study.  

PubMed

According to the 'hard and soft' acid-base principle, mercury is a 'soft metal' and will preferentially form soluble chemical complexes with sulphur-containing ligands. In this work mercury uptake by Chenopodium glaucum L. growing on mercury-contaminated soil was promoted using ammonium thiosulphate. The relative geochemical fractionation of mercury in the soil was subsequently investigated as a function of plant growth with and without thiosulphate amendment. The results indicate that the solubility of mercury is significantly increased through the application of thiosulphate to the soil. Substantially higher mercury levels were found in C. glaucum L. treated with 2 g kg(-1) thiosulphate of soil when compared to the non-treated plants. Compared with initial soil, soluble and exchangeable fractions were increased both in planted and planted treated plants. However, no significant difference was observed between the soils of the planted and planted treated plants. The oxide-bound mercury concentration was significantly decreased for the planted soil (treated and non-treated) at the end of the experiment. Moreover, this fraction was highly correlated with the plant tissue mercury concentration. Taken together, thiosulphate assisted phytoextraction could be used to reduce environmental risk apparent for mercury-contaminated soil through reducing the oxide bound fractions, while managing the bioavailable fractions (compared with no treated plant). PMID:21122988

Wang, Jianxu; Feng, Xinbin; Anderson, Christopher W N; Qiu, Guangle; Ping, Li; Bao, Zhengduo

2011-02-15

19

The relationship between mental retardation and developmental delays in children and the levels of arsenic, mercury and lead in soil samples taken near their mother's residence during pregnancy  

PubMed Central

This study was designed to evaluate the association between lead, mercury, and arsenic in the soil near maternal residences during pregnancy and mental retardation or developmental disability (MR/DD) in children. The study was conducted using 6,048 mothers who did not move throughout their pregnancies and lived within six strips of land in South Carolina and were insured by Medicaid between January 1, 1997 and December 31, 2002. The mother child pairs were then followed until June 1, 2008, through their Medicaid reimbursement files, to identify children diagnosed with MR/DD. The soil was sampled for mercury (Hg), lead (Pb), and As based on a uniform grid, and the soil concentrations were Kriged to estimate chemical concentration at individual locations. We identified a significant relationship between MR/DD and As, and the form of the relationship was nonlinear, after controlling for other known risk factors. PMID:20045663

Liu, Yuan; McDermott, Suzanne; Lawson, Andrew; Aelion, C. Marjorie

2010-01-01

20

Mercury Binding and Mobilization in Post-fire Soil Horizons  

NASA Astrophysics Data System (ADS)

Fires affect watersheds in many ways, including through increased erosion and sediment transport, decreased water quality, and transport and cycling of nutrients and metals. This research addresses mercury (Hg) mobilization within post-fire stream systems, focusing on the influence of soil particle size on binding affinity and potential transport. Using a network of sampling sites within the Piru Creek watershed, affected by the Day Fire during September 2006, total mercury (THg) was measured in soils collected before, during, and after the 2006- 07 storm season. Unburned and burned soil samples from various levels of burn intensity were collected in one- inch increments to a depth of 6 inches and partitioned into fine, medium and coarse fractions. THg concentrations within each grain fraction were measured in triplicate using a Milestone Direct Mercury Analyzer. Initial findings indicate a loss of THg at the surface in the burned soils, as well as increased levels of THg at depths of 2-4 inches. We hypothesize this to be due to volatilization of Hg due to burning, which is either released upward into the atmosphere, or becomes bound to organic matter and settles just below the surface during the formation of a hydrophobic layer. Surface loss may also be attributed to post-fire erosional processes and storm transport. Additionally, analysis of the size fractionated soils reveals that the highest readings of THg in unburned soils occurred in the fine sediments in every case. THg concentrations in fine sediments in the burned soils were not significantly higher than THg concentrations in medium or coarse sands. More recently collected samples show evidence of continuing atmospheric deposition of Hg at the soil surface. Leaching tests are also being performed on this same set of soils to aid in evaluating potential mobilization of THg from transported soils during storm events.

Burke, M. P.; Navarro, B.; Mendez, C.; Lopez, S.; Ferreira, M.; Rademacher, L.; Jay, J.; Hogue, T. S.

2007-12-01

21

Mercury  

MedlinePLUS

Mercury is an element that is found in air, water and soil. It has several forms. Metallic mercury is a shiny, silver-white, odorless liquid. If ... with other elements to form powders or crystals. Mercury is in many products. Metallic mercury is used ...

22

Thermal-treated soil for mercury removal: Soil and phytotoxicity tests  

SciTech Connect

Mercury (Hg) contamination of soils and sediments is one of many environmental problems at the Oak Ridge Reservation, Oak Ridge, TN. Mercury-contaminated soil from the Lower East Fork Poplar Creek (LEFPC) at the Oak Ridge Reservation was treated thermally to reduce Hg concentration to a below target level (20 mg kg{sup {minus}1}) as a pilot scale thermal treatment demonstration. As a part of performance evaluation, the soil characteristics and plant growth response of the untreated and treated soil were examined. The soil treated at 350 C retained most of its original soil properties, but the soil treated at 600 C exhibited considerable changes in mineralogical composition and physicochemical characteristics. Growth and physiological response of the three plant species radish (Raphanus sativus L.), fescue (Festuca arundinacea Schreb.), and oat (Avena sativa L.) indicated adverse effects of the thermal treatment. The addition of N fertilizer had beneficial effects in the 350 C treated soil, but had little beneficial effect in the 600 C treated soil. Some changes of soil characteristics induced by thermal treatment cannot be avoided. Soil characteristics and phytotoxicity test results strongly suggest that changes occurring following the 350 C treatment do not limit the use of the treated soil to refill the excavated site for full-scale remediation. The only problem with the 350 C treatment is that small amounts of Hg compounds (<15 mg kg{sup {minus}1}) remain in the soil and a processing cost of $45/Mg.

Roh, Y.; Edwards, N.T.; Lee, S.Y.; Stiles, C.A.; Armes, S.; Foss, J.E.

2000-04-01

23

Mercury levels in fishes from some Missouri lakes with and without known mercury pollution  

Microsoft Academic Search

Mercurial fungicides used in golf greens can lead to elevated mercury levels in fish from lakes receiving greens drainage. The largemouth bass is the most sensitive indicator with levels ranging from 1-7 mg mercury\\/g of wet tissue in fish taken from lakes that receive drainage from treated greens. Many lakes with no known source of mercury contamination produce bass that

S. R. Koirtyohann; R. Meers; L. K. Graham

1974-01-01

24

Bench-scale studies with mercury contaminated SRS soil  

SciTech Connect

Bench-scale studies with mercury contaminated soil were performed at the SRTC to determine the optimum waste loading obtainable in the glass product without sacrificing durability, leach resistance, and processability. Vitrifying this waste stream also required offgas treatment for the capture of the vaporized mercury. Four soil glasses with slight variations in composition were produced, which were capable of passing the Product Consistency Test (PCT) and the Toxicity Characteristic Leaching Procedure (TCLP). The optimum glass feed composition contained 60 weight percent soil and produced a soda-lime-silica glass when melted at 1,350 C. The glass additives used to produce this glass were 24 weight percent Na{sub 2}CO{sub 3} and 16 weight percent CaCO{sub 3}. Volatilized mercury released during the vitrification process was released to the proposed mercury collection system. The proposed mercury collection system consisted of quartz and silica tubing with a Na{sub 2}S wash bottle followed by a NaOH wash bottle. Once in the system, the volatile mercury would pass through the wash bottle containing Na{sub 2}S, where it would be converted to Hg{sub 2}S, which is a stable form of mercury. However, attempts to capture the volatilized mercury in a Na{sub 2}S solution wash bottle were not as successful as anticipated. Maximum mercury captured was only about 3.24% of the mercury contained in the feed. Mercury capture efforts then shifted to condensing and capturing the volatilized mercury. These attempts were much more successful at capturing the volatile mercury, with a capture efficiency of 34.24% when dry ice was used to pack the condenser. This captured mercury was treated on a mercury specific resin after digestion of the volatilized mercury.

Cicero, C.A.

1995-12-31

25

Effects of mercury on soil microbial communities in tropical soils of French Guyana  

Microsoft Academic Search

In gold mining regions, the risk of soil pollution by mercury is a major environmental hazard, especially in tropical areas where soil microflora plays a major part in soil functioning, major bio-geochemical cycles and carbon turn-over. The impact of mercury pollution on soil microflora should thus be carefully assessed in such environments while taking into consideration the specificities of tropical

Jennifer Harris-Hellal; Tatiana Vallaeys; Evelyne Garnier-Zarli; Noureddine Bousserrhine

2009-01-01

26

Accumulation of mercury in selected plant species grown in soils contaminated with different mercury compounds  

SciTech Connect

The objective of our research is to screen and search for suitable plant species for phyto-remediation of mercury-contaminated soil. Currently our effort is specifically focused on mercury removal from the U.S. Department of Energy (DOE) sites, where mercury contamination is a major concern. In order to cost effectively implement mercury remediation efforts, it is necessary now to obtain an improved understanding of biological means of removing mercury and mercury compounds.. Phyto-remediation is a technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. In particular, phyto-extraction is the uptake of contaminants by plant roots and translocation within the plants to shoots or leaves. Contaminants are generally removed by harvesting the plants. We have investigated phyto-extraction of mercury from contaminated soil by using some of the known metal-accumulating plants since no natural plant species with mercury hyper-accumulating properties has yet been identified. Different natural plant species have been studied for mercury uptake, accumulation, toxicity and overall mercury removal efficiency. Various mercury compounds, such as HgS, HgCl{sub 2}, and Hg(NO{sub 3}){sub 2}, were used as contaminant sources. Different types of soil were examined and chosen for phyto-remediation experiments. We have applied microscopy and diffuse reflectance spectrometry as well as conventional analytical chemistry to monitor the phyto-remediation processes of mercury uptake, translocation and accumulation, and the physiological impact of mercury contaminants on selected plant species. Our results indicate that certain plant species, such as beard grass (Polypogon monospeliensis), accumulated a very limited amount of mercury in the shoots (<65 mg/kg), even though root mercury accumulation is significant (maximum 2298 mg/kg). Consequently, this plant species may not be suitable for mercury phyto-remediation. Other plant species, such as Indian mustard (Brassica juncea), a well-studied metal accumulator, exhibited severe chlorosis symptoms during some experiments. Among all the plant species studied, Chinese brake fern (Pteris vittata) accumulated significant amount of mercury in both roots and shoots and hence may be considered as a potential candidate for mercury phyto-extraction. During one experiment, Chinese brake ferns accumulated 540 mg/kg and 1469 mg/kg in shoots after 18 days of growing in soils treated with 500 parts-per-million (ppm) and 1000 ppm HgCl{sub 2} powder, respectively; no visual stress symptoms were observed. We also studied mercury phyto-remediation using aged soils that contained HgS, HgCl{sub 2}, or Hg(NO{sub 3}){sub 2}. We have found that up to hundreds of ppm mercury can be accumulated in the roots of Indian mustard plants grown with soil contaminated by mercury sulfide; HgS is assumed to be the most stable and also the predominant mercury form in flood plain soils. We have also started to investigate different mercury uptake mechanisms, such as root uptake of soil contaminant and foliar mercury accumulation from ambient air. We have observed mercury translocation from roots to shoot for Chinese fern and two Indian mustard varieties. (authors)

Su, Yi; Han, Fengxiang; Shiyab, Safwan; Chen, Jian; Monts, David L. [Institute for Clean Energy Technology (ICET), Mississippi State University, 205 Research Blvd, Starkville, MS 39759 (United States)

2007-07-01

27

Removal of Mercury from Clayey Soils Using Electrokinetics  

Microsoft Academic Search

Numerous sites have been polluted with mercury as a result of accidental spills and improper disposal practices, and these mercury-contaminated sites may have adverse effects on human health and the environment. Innovative and cost-effective remediation techniques are urgently needed, and this study was performed to investigate the use of electrokinetics for mercury-contaminated soils. Initially, batch tests were performed on two

Krishna R. Reddy; Carlos Chaparro; Richard E. Saichek

2003-01-01

28

Mercury in soils and plants in an abandoned cinnabar mining area (SW Spain)  

Microsoft Academic Search

An abandoned cinnabar mining area located in the South-West of Spain has been studied with the aim of assessing its mercury pollution level and enhancing the knowledge about the Hg soil\\/plant relationship. To do so, soils and plants were sampled near an inactive smelter and around two mining sites present in this area. Critical total Hg concentrations were found in

A. García-Sánchez; A. Murciego; E. Álvarez-Ayuso; I. Santa Regina; M. A. Rodríguez-González

2009-01-01

29

Binding of mercury in soils and attic dust in the Idrija mercury mine area (Slovenia)  

Microsoft Academic Search

Total Hg concentrations and Hg speciation were determined in soils and attic dust in a 160 km2 area around Idrija mercury mine. Attic dust as well as a sample of soil was collected at 100 locations. Mercury phases were separated into cinnabar and non-cinnabar compounds via a thermo-desorption technique. The amount of the non-cinnabar fraction is important since it is potentially

Mateja Gosar; Robert Šajn; Harald Biester

2006-01-01

30

Distribution of mercury species in soil from a mercury-contaminated site  

Microsoft Academic Search

The distribution of mercury species was determined in soil from a site with Hg contamination. Mercury contamination was primarily confined to the top 40 cm of soil, and the concentration of total Hg ranged from 0.5 to 3000 µg Hg g-1. Of total Hg present, we determined that 91% was inorganic, 0.01% organic (as methyl Hg), and 6% elemental Hg.

N. W. Revis; T. R. Osborne; G. Holdsworth; C. Hadden

1989-01-01

31

Bench-scale vitrification studies with Savannah River Site mercury contaminated soil  

SciTech Connect

The Savannah River Technology Center (SRTC) has been charted by the Department of Energy (DOE)--Office of Technology Development (OTD) to investigate vitrification technology for the treatment of Low Level Mixed Wastes (LLMW). In fiscal year 1995, mercury containing LLMW streams were targeted. In order to successfully apply vitrification technology to mercury containing LLMW, the types and quantities of glass forming additives necessary for producing homogeneous glasses from the wastes have to be determined and the treatment for the mercury portion must also be determined. Selected additives should ensure that a durable and leach resistant waste form is produced, while the mercury treatment should ensure that hazardous amounts of mercury are not released into the environment. The mercury containing LLMW selected for vitrification studies at the SRTC was mercury contaminated soil from the TNX pilot-plant facility at the Savannah River Site (SRS). Samples of this soil were obtained so bench-scale vitrification studies could be performed at the SRTC to determine the optimum waste loading obtainable in the glass product without sacrificing durability and leach resistance. Vitrifying this waste stream also required offgas treatment for the capture of the vaporized mercury.

Cicero, C.A.; Bickford, D.F.

1995-12-31

32

Impact of gold mining associated with mercury contamination in soil, biota sediments and tailings in Kenya.  

PubMed

This work considered the environmental impact of artisanal mining gold activity in the Migori-Transmara area (Kenya). From artisanal gold mining, mercury is released to the environment, thus contributing to degradation of soil and water bodies. High mercury contents have been quantified in soil (140 ?g kg(-1)), sediment (430 ?g kg(-1)) and tailings (8,900 ?g kg(-1)), as expected. The results reveal that the mechanism for transporting mercury to the terrestrial ecosystem is associated with wet and dry depositions. Lichens and mosses, used as bioindicators of pollution, are related to the proximity to mining areas. The further the distance from mining areas, the lower the mercury levels. This study also provides risk maps to evaluate potential negative repercussions. We conclude that the Migori-Transmara region can be considered a strongly polluted area with high mercury contents. The technology used to extract gold throughout amalgamation processes causes a high degree of mercury pollution around this gold mining area. Thus, alternative gold extraction methods should be considered to reduce mercury levels that can be released to the environment. PMID:24943890

Odumo, Benjamin Okang'; Carbonell, Gregoria; Angeyo, Hudson Kalambuka; Patel, Jayanti Purshottam; Torrijos, Manuel; Rodríguez Martín, José Antonio

2014-11-01

33

Total mercury, organic mercury and mercury fractionation in soil profiles from the Almadén mercury mine area.  

PubMed

Soil profiles located in the mining district of Almadén were investigated for total Hg, organic Hg fraction and Hg distribution by selective sequential extraction. A four-step sequential extraction method (labile Hg species, humic and fulvic complexes, elemental Hg and bound to crystalline oxides and Hg sulfide and refractory species) was performed. Total Hg concentrations ranged from 13 to 64 mg per kg dry mass. A clear relationship between the depth and Hg content was found since Hg concentration decreases downwards, which is indicative of anthropogenic contamination via deposition processes from nearby mine waste. Significant organic Hg concentrations were found in all the tested soil profiles ranging from 79 to 287 ?g kg(-1) (dry weight). It seems that organic Hg was strongly influenced by elemental Hg (r = 0.79) and to a lesser extent by the organic carbon content (r = 0.57). The fractionation revealed that Hg exists mainly as cinnabar in the studied soils, which is one of the least available and mobile Hg species, and as elemental Hg as well. The most mobile Hg fractions only accounted for 3.2 to 7.7% of the total Hg content, with the main contribution being the humic and fulvic complexes fraction. The elemental Hg fraction increased with depth indicating a migration to deeper soil layers. In contrast, the surface layers showed an enrichment in the fraction bound to sulfide, which means that Hg is mostly deposited as cinnabar particles from non-processed ore in this area. PMID:24441501

Fernández-Martínez, Rodolfo; Rucandio, Isabel

2014-02-01

34

Atmospheric emission and plant uptake of mercury from agricultural soils near the Almaden mercury mine  

Microsoft Academic Search

Surface soils collected near the Almaden, Spain, mercury mine reflected increasing concentrations of mercury (Hg) with proximity to the mine due to weathered mineral deposits and to atmospheric deposition of Hg from the smelter. Extractions with NaHCOâ or NHâOAc removed small amounts of Hg from both control (20 km from the mine; total Hg = 2.3 ..mu..g\\/g) and mine site

S. E. Lindberg; D. R. Jackson; J. W. Huckabee; S. A. Janzen; M. J. Levin; J. R. Lund

1979-01-01

35

The role of natural purified humic acids in modifying mercury accessibility in water and soil.  

PubMed

Contamination of soils with mercury can be a serious problem. It can be mobilized or stabilized by humic substances (HS) containing binding sites with reduced sulfur that can have different binding capacities for CH(3)Hg(+) and for Hg(2+). In this work we investigated the influence of different humic acids (HAs, extracted from lignite, compost, and forest soil) on mercury mobility and availability, both in a model solution and in soil samples from a mercury-polluted region. The technique of diffusive gradients in thin-films (DGT), which is capable of measuring: (i) free metal in solution; (ii) dissociated metal complexes previously mobilized by HA; (iii) mobilized metal-HA complexes that liberate metals by dissociation or by exchange reaction between the metal-HA complexes and the chelating groups on the resin-gel, was used in solutions and soils. The DGT measurements in solution, together with ultrafiltration, allowed estimation of the lability of Hg-HA complexes. Ultrafiltration results were also compared with predictions made by the windermere humic-aqueous model (WHAM). According to both these different approaches, Hg(2+) resulted nearly 100% complexed by HAs, whereas results from ultrafiltration showed that 32 to 72% of the CH(3)Hg(+) was bound to the HAs, with higher values for compost and lower values for forest and Aldrich HA. The DGT-measured mercury in soils was below 0.20 microg L(-1), irrespective of the extent of the contamination. Addition of HA increased the concentration of DGT-measured mercury in soil solution up to 100-fold in the contaminated soil and up to 30-fold in the control soil. The level of the increase also depended on the HA. The smallest increase (about 10 times) was found for lignite HA in both control and contaminated soils. The addition of forest HA gave the largest increases in DGT-measured mercury, in particular for the contaminated soil. Overall, the results demonstrated that DGT can be used for estimating the lability of mercury complexes in solution and for verifying enhanced mercury mobility when HA is added to contaminated soils. PMID:19202019

Cattani, I; Zhang, H; Beone, G M; Del Re, A A M; Boccelli, R; Trevisan, M

2009-01-01

36

Mercury uptake by Silene vulgaris grown on contaminated spiked soils.  

PubMed

Mercury is a highly toxic pollutant with expensive clean up, because of its accumulative and persistent character in the biota. The objective of this work was to evaluate the effectiveness of Silene vulgaris, facultative metallophyte which have populations on both non-contaminated and metalliferous soils, to uptake Hg from artificially polluted soils. A pot experiment was carried out in a rain shelter for a full growth period. Two soils (C pH = 8.55 O.M. 0.63% and A pH = 7.07 O.M. 0.16%) were used, previously contaminated with Hg as HgCl(2) (0.6 and 5.5 mg Hg kg(-1) soil). Plants grew healthy and showed good appearance throughout the study without significantly decreasing biomass production. Mercury uptake by plants increased with the mercury concentration found in both soils. Differences were statistically significant between high dosage and untreated soil. The fact that S. vulgaris retains more mercury in root than in shoot and also, the well known effectiveness of these plants in the recovering of contaminated soils makes S. vulgaris a good candidate to phytostabilization technologies. PMID:20708330

Pérez-Sanz, Araceli; Millán, Rocío; Sierra, M José; Alarcón, Remedios; García, Pilar; Gil-Díaz, Mar; Vazquez, Saúl; Lobo, M Carmen

2012-03-01

37

Kinetics of Mercury(II) Adsorption and Desorption on Soil  

E-print Network

Kinetics of Mercury(II) Adsorption and Desorption on Soil Y U J U N Y I N , H E R B E R T E . A L L of Delaware, Newark, Delaware 19716 D O N A L D L . S P A R K S Department of Plant and Soil Sciences kinetics of Hg(II) on four soils at pH 6 were investigated to discern the mechanisms controlling

Sparks, Donald L.

38

Natural mercury isotope variation in coal deposits and organic soils  

SciTech Connect

There is a need to distinguish among sources of Hg to the atmosphere in order to more fully understand global Hg pollution. In this study we investigate whether coal deposits within the United States, China, and Russia-Kazakhstan, which are three of the five greatest coal-producing regions, have diagnostic Hg isotopic fingerprints that can be used to discriminate among Hg sources. We also investigate the Hg isotopic composition of modern organic soil horizons developed in areas distant from point sources of Hg in North America. Mercury stored in coal deposits displays a wide range of both mass dependent fractionation and mass independent fractionation. {delta}{sup 202}Hg varies in coals by 3{per_thousand} and {Delta}{sup 201}Hg varies by 0.9{per_thousand}. Combining these two Hg isotope signals results in what may be a unique isotopic 'fingerprint' for many coal deposits. Mass independent fractionation of mercury has been demonstrated to occur during photochemical reactions of mercury. This suggests that Hg found in most coal deposits was subjected to photochemical reduction near the Earth's surface prior to deposition. The similarity in MDF and MIF of modern organic soils and coals from North America suggests that Hg deposition from coal may have imprinted an isotopic signature on soils. This research offers a new tool for characterizing mercury inputs from natural and anthropogenic sources to the atmosphere and provides new insights into the geochemistry of mercury in coal and soils. 35 refs., 2 figs., 1 tab.

Abir, Biswas; Joel D. Blum; Bridget A. Bergquist; Gerald J. Keeler; Zhouqing Xie [University of Michigan, Ann Arbor, MI (United States). Department of Geological Sciences

2008-11-15

39

Wavelengths, Energy Level Classifications, and Energy Levels for the Spectrum of Neutral Mercury  

E-print Network

Wavelengths, Energy Level Classifications, and Energy Levels for the Spectrum of Neutral Mercury E A comprehensive critically evaluated compilation of the most accurate wavelength measurements for classified lines wavelengths; atomic wave numbers; energy level classifications; infrared wavelengths; mercury; ultraviolet

Magee, Joseph W.

40

Mercury dispersion in soils of an abandoned lead-zinc-silver mine, San Quintín (Spain)  

NASA Astrophysics Data System (ADS)

The mine considered on this work, namely San Quintín, is a filonian field with hydrothermal ores exploited during almost fifty years (1887-1934), producing 550.000Tm of galena, 550Tm of silver and 5.000 of sphalerite. Some rewashing works of tailings muds was achieved in recent times (1973-1985), including flotation tests of cinnabar ore from Almadén mines. The main problems remaining on the site are an active acid mine drainage (with pH ~ 2) and heavy metal dispersion on soils including gaseous mercury emissions. We present here results of a survey including soils sampling with mercury analysis and other pedological parameters, as well as determinations of mercury inmission in the atmosphere, using a common sampling grid. Analysis of soils samples has been carried out using an atomic absorption spectrometer AMA254, while air determinations were made by the same technique, using a Lumex RA-915+. The maps have been obtained by means of SURFER 8 software, as well as by ArcGIS software, and puts forward dispersion of mercury from cinnabar ore dump (108 ?g×g-1) to nearby soils (0.3 ?g×g-1 at 700 m of distance). The dispersion of mercury vapor exceed WHO level for chronic exposure (200 ng×m-3) in a small area (250 meters from cinnabar dump).

Esbrí, José Maria; Martín-Crespo, T.; Gómez-Ortiz, D.; Monescillo, C. I.; Lorenzo, S.; Higueras, P.

2010-05-01

41

Estimations of historical atmospheric mercury concentrations from mercury refining and present-day soil concentrations of total mercury in Huancavelica, Peru.  

PubMed

Detailed Spanish records of cinnabar mining and mercury production during the colonial period in Huancavelica, Peru were examined to estimate historical health risks to the community from exposure to elemental mercury (Hg) vapor resulting from cinnabar refining operations. Between 1564 and 1810, nearly 17,000 metric tons of Hg were released to the atmosphere in Huancavelica from Hg production. AERMOD was used with estimated emissions and source characteristics to approximate historic atmospheric concentrations of mercury vapor. Modeled 1-hour and long-term concentrations were compared with present-day inhalation reference values for elemental Hg. Estimated 1-hour maximum concentrations for the entire community exceeded present-day occupational inhalation reference values, while some areas closest to the smelters exceeded present-day emergency response guideline levels. Estimated long-term maximum concentrations for the entire community exceeded the EPA Reference Concentration (RfC) by a factor of 30 to 100, with areas closest to the smelters exceeding the RfC by a factor of 300 to 1000. Based on the estimated historical concentrations of Hg vapor in the community, the study also measured the extent of present-day contamination throughout the community through soil sampling and analysis. Total Hg in soils sampled from 20 locations ranged from 1.75 to 698 mg/kg and three adobe brick samples ranging from 47.4 to 284 mg/kg, consistent with other sites of mercury mining and use. The results of the soil sampling indicate that the present-day population of Huancavelica is exposed to levels of mercury from legacy contamination which is currently among the highest worldwide, consequently placing them at potential risk of adverse health outcomes. PMID:22542225

Robins, Nicholas A; Hagan, Nicole; Halabi, Susan; Hsu-Kim, Heileen; Gonzales, Ruben Dario Espinoza; Morris, Mark; Woodall, George; Richter, Daniel deB; Heine, Paul; Zhang, Tong; Bacon, Allan; Vandenberg, John

2012-06-01

42

Bioavailability of mercury in East Fork Poplar Creek soils  

SciTech Connect

The initial risk assessment for the East Fork Poplar Creek (EFPC) floodplain in Oak Ridge, Tennessee, a superfund site heavily contaminated with mercury, was based upon a reference dose for mercuric chloride, a soluble mercury compound not expected to be present in the floodplain, which is frequently saturated with water. Previous investigations had suggested mercury in the EFPC floodplain was less soluble and therefore less bioavailable than mercuric chloride, possibly making the results of the risk assessment unduly conservative. A bioavailability study, designed to measure the amount of mercury available for absorption in a child`s digestive tract, the most critical risk endpoint and pathway, was performed on twenty soils from the EFPC floodplain. The average percentage of mercury released during the study for the twenty soils was 5.3%, compared to 100% of the compound mercuric chloride subjected to the same conditions. Alteration of the procedure to test additional conditions possible during soil digestion did not appreciably alter the results. Therefore, use of a reference dose for mercuric chloride in the EFPC risk assessment without inclusion of a corresponding bioavailability factor may be unduly conservative.

Barnett, M.O.; Turner, R.R.

1995-05-01

43

Organ mercury levels in infants with omphaloceles treated with organic mercurial antiseptic  

Microsoft Academic Search

Samples of fresh and fixed tissues from infants with exomphalos treated by thiomersal application were analysed for mercury content. The results showed that thiomersal can induce blood and organ levels of organic mercury which are well in excess of the minimum toxic level in adults and fetuses. The analysis of fresh and fixed tissues must be carefully controlled against normal

D. G. Fagan; J S Pritchard; T. W. Clarkson; M. R. Greenwood

1977-01-01

44

Mercury exposure in French Guiana: Levels and determinants  

SciTech Connect

Mercury is used widely for gold extraction in French Guiana and throughout the entire Amazon basin. To evaluate contamination among the general population, the authors chose individuals who attended 13 health centers and maternity hospitals dispersed geographically across the territory and served Guiana`s different populations. Five hundred individuals (109 pregnant women, 255 other adults, and 136 children) who received care at one of the centers were selected randomly for this study. Each individual answered a questionnaire and provided a hair sample. The authors determined mercury in hair with atomic absorption spectrometry. The following mean levels of mercury were observed: 1.6 {micro}g/g among pregnant women; 3.4 {micro}g/g among other adults; and 2.5 {micro}g/g among children. Diet factors contributed the most to mercury levels, especially consumption of freshwater fish and livers from game. Other factors, including age, dental amalgams, use of skin-lightening cosmetics, and residence near a gold-mining community, did not contribute significantly to mercury levels. Overall, 12% of the samples contained mercury levels in excess of 10 {micro}g/g, but in some Amerindian communities up to 79% of the children had hair mercury levels that exceeded 10 {micro}g/g. The results of this study indicated that (a) diet played a predominant role in total mercury burden, and (b) in some communities, mercury contamination exceeded safe levels.

Cordier, S.; Mandereau, L. [Inst. National de Sante et de Recherche Medicale, Villejuif (France); Grasmick, C. [Direction Generale de la Sante, Paris (France); Paquier-Passelaigue, M. [Direction Dept. des Affaires Sanitaires et Sociales, Cayenne (France); Weber, J.P. [Centre de Toxicologie du Quebec (Canada); Jouan, M. [Reseau National de Sante Publique, St. Maurice (France)

1998-07-01

45

Bench-scale studies with mercury contaminated SRS soil  

SciTech Connect

The Savannah River Technology Center (SRTC) has been charactered by the Department of Enregy (DOE) - Office of Technology Development (OTD) to investigate vitrification technology for the treatment of Low Level Mixed Wastes (LLMW). In fiscal year 1995, LLW streams containing mercury and organics were targeted. This report will present the results of studies with mercury contaminated waste. In order to successfully apply vitrification technology to LLMW, the types and quantities of glass forming additives necessary for producing homogeneous glasses from the wastes had to be determined, and the treatment for the mercury portion had to also be determined. The selected additives had to ensure that a durable and leach resistant waste form was produced, while the mercury treatment had to ensure that hazardous amounts of mercury were not released into the environment.

Cicero, C.A.

1996-05-08

46

Impact of Wildfire on Levels of Mercury in Forested Watershed Systems - Voyageurs National Park, Minnesota  

USGS Publications Warehouse

Atmospheric deposition of mercury to remote lakes in mid-continental and eastern North America has increased approximately threefold since the mid-1800s (Swain and others, 1992; Fitzgerald and others, 1998; Engstrom and others, 2007). As a result, concerns for human and wildlife health related to mercury contamination have become widespread. Despite an apparent recent decline in atmospheric deposition of mercury in many areas of the Upper Midwest (Engstrom and Swain, 1997; Engstrom and others, 2007), lakes in which fish contain levels of mercury deemed unacceptable for human consumption and possibly unacceptable for fish-consuming wildlife are being detected with increasing frequency. In northern Minnesota, Voyageurs National Park (VNP) (fig. 1) protects a series of southern boreal lakes and wetlands situated on bedrock of the Precambrian Canadian Shield. Mercury contamination has become a significant resource issue within VNP as high concentrations of mercury in loons, bald eagle eaglets, grebes, northern pike, and other species of wildlife and fish have been found. The two most mercury-contaminated lakes in Minnesota, measured as methylmercury in northern pike (Esox lucius), are in VNP. Recent multidisciplinary U.S. Geological Survey (USGS) research demonstrated that the bulk of the mercury in lake waters, soils, and fish in VNP results from atmospheric deposition (Wiener and others, 2006). The study by Wiener and others (2006) showed that the spatial distribution of mercury in watershed soils, lake waters, and age-1 yellow perch (Perca flavescens) within the Park was highly variable. The majority of factors correlated for this earlier study suggested that mercury concentrations in lake waters and age-1 yellow perch reflected the influence of ecosystem processes that affected within-lake microbial production and abundance of methylmercury (Wiener and others, 2006), while the distribution of mercury in watershed soils seemed to be partially dependent on forest disturbance, especially the historic forest fire pattern (Woodruff and Cannon, 2002). Forest fire has an essential role in the forest ecosystems of VNP (Heinselman, 1996). Because resource and land managers need to integrate both natural wildfire and prescribed fire in management plans, the potential influence of fire on an element as sensitive to the environment as mercury becomes a critical part of their decisionmaking. A number of recent studies have shown that while fire does have a significant impact on mercury at the landscape level, the observed effects of fire on aquatic environments are highly variable and unpredictable (Caldwell and others, 2000; Garcia and Carrigan, 2000; Kelly and others, 2006; Nelson and others, 2007). Caldwell and others (2000) described an increase in methylmercury in reservoir sediments resulting from mobilization and transport of charred vegetative matter following a fire in New Mexico. Krabbenhoft and Fink (2000) attributed increases in total mercury concentrations in young-of-the-year fish in the Florida Everglades to release of mercury resulting from peat oxidation following fires. A fivefold increase in whole-body mercury accumulation by rainbow trout (Oncorhynchus mykiss) following a fire in Alberta, Canada, apparently resulted from increased nutrient concentrations that enhanced productivity and restructured the food web of a lake within the fire's burn footprint (Kelly and others, 2006). For this study, we determined the short-term effects of forest fire on mercury concentrations in terrestrial and aquatic environments in VNP by comparing and contrasting mercury concentrations in forest soils, lake waters, and age-1 yellow perch for a burned watershed and an adjacent lake, with similar samples from watersheds and lakes with no fire activity (control watersheds and lakes). The concentration of total mercury in whole, 1-year-old yellow perch serves as a good biological indicator for monitoring trends in methylmercury conce

Woodruff, Laurel G.; Sandheinrich, Mark B.; Brigham, Mark E.; Cannon, William F.

2009-01-01

47

Phyto extraction and accumulation of mercury in selected plant species grown in soil contaminated with different mercury compounds  

SciTech Connect

The objective of our research is to screen and search for suitable plant species for phyto-remediation of mercury-contaminated soil. Currently our effort is specifically focused on mercury removal from the U.S. Department of Energy's (DOE) Oak Ridge Site, where mercury contamination is a major concern in the Y-12 Watershed area. In order to cost effectively implement those remediation efforts currently planned for FY09, it is necessary now to obtain an improved understanding of biological means of removing mercury and mercury compounds from the Oak Ridge ecosystem. Phyto-remediation is a technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. In particular, phyto-extraction is the uptake of contaminants by plant roots and translocation within the plants to shoots or leaves. Contaminants are generally removed by harvesting the plants. We have investigated phyto-extraction of mercury from contaminated soil by using some of the known metal accumulating wild plants since no natural plant species with mercury hyper-accumulating properties has yet been identified. Different natural plant species have been studied for mercury uptake, accumulation, toxicity and overall mercury removal efficiency. Various mercury compounds, such as HgS, HgCl{sub 2} and Hg(NO{sub 3}){sub 2}, were used as contaminant sources. Different types of soil were examined and chosen for phyto-remediation experiments. We have applied microscopy and diffuse reflectance spectrometry as well as conventional analytical chemistry to monitor the phyto-remediation processes of mercury uptake, translocation and accumulation; and the physiological impact of mercury contaminants on selected plant species. Our results indicate that certain plant species, such as beard grass (Polypogon monospeliensis), accumulated a very limited amount of mercury in the shoots (<65 mg/kg), even though root mercury accumulation is significant (maximum 2298 mg/kg). Consequently, this plant species may not be suitable for mercury phyto-remediation. Other plant species, such as Indian mustard (Brassica juncea), a well-studied metal accumulator, exhibited severe chlorosis symptoms during some experiments. Among all the plant species studied, Chinese brake fern (Pteris vittata) accumulated significant amount of mercury in both roots and shoots and hence may be considered as a potential candidate for mercury phyto-extraction. During one experiment, brake ferns accumulated 540 mg/kg and 1469 mg/kg in shoots after 18 days of growing in soils treated with 500 ppm and 1000 ppm HgCl{sub 2} powder, respectively; no visual stress symptoms were observed. We also studied mercury phyto-remediation using aged soils that contaminated HgS, HgCl{sub 2}, and Hg(NO{sub 3}){sub 2}. We have found that up to hundreds of ppm mercury can be accumulated in the roots of Indian mustard plants grown with soil contaminated by mercury sulfide; HgS is assumed to be the most stable and also the predominant mercury form in Oak Ridge flood plain soils. We have also started to investigate different mercury uptake mechanisms, such as root uptake of soil contaminant and foliar mercury accumulation from ambient air. (authors)

Su, Y.; Han, F.; Shiyab, S.; Monts, D.L. [Mississippi State Univ., Institute for Clean Energy Technology (ICET), Starkville, MS (United States)

2007-07-01

48

Changes in Mercury Volatilization between Planted and Unplanted Soils  

NASA Astrophysics Data System (ADS)

An important question with respect to the Hg biogeochemical cycle is how does the presence of plants affect the flux of Hg from a soil? Previous research has shown that with leaf development over a growing season and increased soil shading Hg emission decreases, while others have suggested that increased activity of rhizosphere bacteria due to the presence of plants would result in the increased Hg emission from soils. This study examined Hg release to the air associated with low Hg containing soils from three states—Indiana, Alabama, and Ohio over 24 h periods. Hg flux was quantified on a seasonal time step over one year for bare soil and for soil when planted with perennial rye grass (Lolium perennel). For the latter fluxes were measured 5 and 10 weeks after planting. Preliminary data assessment suggests that both planted and unplanted substrates in the summer are generally a net source of Hg to the atmosphere with total daily flux ranging from -50 to 1000 ng/m2 day. Fluxes observed for planted soils exhibited diel trends that were the opposite of that measured for bare soils, that is maximum Hg flux was observed during the night instead of at midday. Planted Indiana and Ohio soils emitted a lower Hg flux than the bare soils while the Alabama soils were not consistent. Good correlations were observed between flux versus soil moisture, soil temperature, local ozone concentration, and solar radiation for bare soils however correlation coefficients were not as strong for the planted materials. Mercury concentration of foliar material showed that plant uptake could not account for reduced flux at midday. This work suggests that the presence of plants does alter the flux of Hg occurring from soils.

Briggs, C.; Gustin, M. S.

2010-12-01

49

Mercury Mobilization in a Contaminated Industrial Soil for Phytoremediation  

Microsoft Academic Search

The aim of this work was to investigate the possibility of using plants for mercury (Hg) removal from a contaminated industrial soil, increasing the metal's bioaccessibility by using mobilizing agents: ammonium thiosulphate [(NH4)2S2O3] and potassium iodide (KI). The selected plant species were Brassica juncea and Poa annua. The addition of the mobilizing agents promoted Hg uptake by plants, with respect

Francesca Pedron; Gianniantonio Petruzzelli; Meri Barbafieri; Eliana Tassi; Paolo Ambrosini; Leonardo Patata

2011-01-01

50

Remediation aspect of microbial changes of plant rhizosphere in mercury contaminated soil  

Microsoft Academic Search

Phytoremediation, an approach that uses plants to remediate contaminated soil through degradation, stabilization or accumulation,\\u000a may provide an efficient solution to some mercury contamination problems. This paper presents growth chamber experiments that\\u000a tested the ability of plant species to stabilize mercury in soil. Several indigenous herbaceous species and Salix viminalis were grown in soil collected from a mercury-contaminated site in

Aleksandra Sas-Nowosielska; Regina Galimska-Stypa; Rafa? Kucharski; Urszula Zielonka; Eugeniusz Ma?kowski; Laymon Gray

2008-01-01

51

Trace-level mercury removal from surface water  

SciTech Connect

Many sorbents have been developed for the removal of mercury and heavy metals from waters; however, most of the data published thus far do not address the removal of mercury to the target levels represented in this project. The application to which these sorbents are targeted for use is the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Sorbents with thiouronium, thiol, amine, sulfur, and proprietary functional groups were selected for these studies. Mercury was successfully removed from surface water via adsorption onto Ionac SR-4 and Mersorb resins to levels below the target goal of 12 ng/L in batch studies. A thiol-based resin performed the best, indicating that over 200,000 volumes of water could be treated with one volume of resin. The cost of the resin is approximately $0.24 per 1,000 gal of water.

Klasson, K.T.; Bostick, D.T.

1998-06-01

52

Mercury in the surface soil and cassava, Manihot esculenta (flesh, leaves and peel) near goldmines at Bogoso and Prestea, Ghana.  

PubMed

Mercury amalgamation is used indiscriminately in the recovery of gold by small-scale native gem winners in Ghana. Mercury is released into the environment in the form of wastewater, tailing and vapor from the roasting of amalgam to separate gold. The study looked at the levels of total mercury concentration in surface soil and cassava crop from farms located within the vicinities of Bogoso and Prestea Goldmines. The surface soil total mercury concentrations ranged between 125.29 and 352.52 ?g/kg whiles cassava had between 66.60 and 195.47 ?g/kg. The results showed proportionately more deposits at higher distances in 15-30 cm soil zone and less deposits at higher distances on leaves with relatively high uptake of the metal occurred at higher distances from the mines into the peels. These results suggest serious mercury pollution to the surface soil and the cassava crop but the speciation exercise showed that mercury is not in the free state, rather bound to hydroxides and organic compounds as complexes. PMID:23052587

Adjorlolo-Gasokpoh, A; Golow, A A; Kambo-Dorsa, J

2012-12-01

53

Characterization of mercury forms in contaminated floodplain soils  

SciTech Connect

The chemical form or speciation of Hg in the floodplain soils of the East Fork Poplar Creek in Oak Ridge TN, a site contaminated from past industrial activity, was investigated. Hg speciation in the soils is an important factor in controlling the fate and effect of mercury at the site and in assessing human health and ecological risk. Application of 3 different sequential extraction speciation schemes indicated the Hg at the site was predominantly relatively insoluble mercuric sulfide or metallic Hg, though the relative proportions of each did not agree well between procedures. Application of x-ray and electron beam studies to site soils confirmed the presence of metacinnabar, a form of mercuric sulfide, the first known evidence of authigenic mercuric sulfide formation in soils.

Barnett, M.O.; Turner, R.R.; Henson, T.J. [Oak Ridge National Lab., TN (United States); Harris, L.A.; Melton, R.E.; Stevenson, R.J. [Oak Ridge K-25 Site, TN (United States)

1994-12-31

54

Mercury  

SciTech Connect

Papers are presented on future observations of and missions to Mercury, the photometry and polarimetry of Mercury, the surface composition of Mercury from reflectance spectrophotometry, the Goldstone radar observations of Mercury, the radar observations of Mercury, the stratigraphy and geologic history of Mercury, the geomorphology of impact craters on Mercury, and the cratering record on Mercury and the origin of impacting objects. Consideration is also given to the tectonics of Mercury, the tectonic history of Mercury, Mercury's thermal history and the generation of its magnetic field, the rotational dynamics of Mercury and the state of its core, Mercury's magnetic field and interior, the magnetosphere of Mercury, and the Mercury atmosphere. Other papers are on the present bounds on the bulk composition of Mercury and the implications for planetary formation processes, the building stones of the planets, the origin and composition of Mercury, the formation of Mercury from planetesimals, and theoretical considerations on the strange density of Mercury.

Vilas, F.; Chapman, C.R.; Matthews, M.S.

1988-01-01

55

Investigating the control of mercury volatilization from contaminated soil  

NASA Astrophysics Data System (ADS)

In previous investigations of growing earthworms, Lumbricus terrestris, in contaminated soil, we have found that volatilization of mercury (Hg) to be an active process. The question to be answered is what causes the reduction of Hg to a more volatile state in the soil, could it be the earthworms? A series of laboratory tests were conducted to determine the mechanism of Hg reduction. The tests revealed that earthworms bioaccumulate the Hg in their tissue, but do not aid in the reduction process. Microbial reduction of the Hg appears to be the mechanism. Two dissimilar soil types were tested; both were heated for 96 hours at 100oC. After cooling, both soil types were spiked with 100 mg of Hg per Kg of soil. Integrated Hg vapor samples were collected immediately above the soil surface over a 3 day period and analyzed by cold vapor atomic adsorption. After heat treatment both soil types had a statistically significantly higher rate of volatilization than unheated soils. We interpret this result as indicating that heating preferentially selected microbial spores that facilitated the Hg reduction.

Steffy, D. A.; Nichols, A.

2009-12-01

56

Wildfires threaten mercury stocks in northern soils Merritt R. Turetsky,1,2  

E-print Network

methylmercury, boreal wetlands might soon transition to hotspots for atmospheric mercury emissions. Estimates organic soil mercury stocks and burn areas across western, boreal Canada for use in fire emission models that explore controls of burn area, consumption severity, and fuel loading on atmospheric mercury emissions

Turetsky, Merritt

57

Potential bioremediation of mercury-contaminated substrate using filamentous fungi isolated from forest soil.  

PubMed

The use of filamentous fungi in bioremediation of heavy metal contamination has been developed recently. This research aims to observe the capability of filamentous fungi isolated from forest soil for bioremediation of mercury contamination in a substrate. Six fungal strains were selected based on their capability to grow in 25 mg/L Hg(2+)-contaminated potato dextrose agar plates. Fungal strain KRP1 showed the highest ratio of growth diameter, 0.831, thus was chosen for further observation. Identification based on colony and cell morphology carried out by 18S rRNA analysis gave a 98% match to Aspergillus flavus strain KRP1. The fungal characteristics in mercury(II) contamination such as range of optimum pH, optimum temperature and tolerance level were 5.5-7 and 25-35°C and 100 mg/L respectively. The concentration of mercury in the media affected fungal growth during lag phases. The capability of the fungal strain to remove the mercury(II) contaminant was evaluated in 100 mL sterile 10 mg/L Hg(2+)-contaminated potato dextrose broth media in 250 mL Erlenmeyer flasks inoculated with 10(8) spore/mL fungal spore suspension and incubation at 30°C for 7 days. The mercury(II) utilization was observed for flasks shaken in a 130 r/min orbital shaker (shaken) and non-shaken flasks (static) treatments. Flasks containing contaminated media with no fungal spores were also provided as control. All treatments were done in triplicate. The strain was able to remove 97.50% and 98.73% mercury from shaken and static systems respectively. A. flavus strain KRP1 seems to have potential use in bioremediation of aqueous substrates containing mercury(II) through a biosorption mechanism. PMID:25079829

Kurniati, Evi; Arfarita, Novi; Imai, Tsuyoshi; Higuchi, Takaya; Kanno, Ariyo; Yamamoto, Koichi; Sekine, Masahiko

2014-06-01

58

Mercury exposure may suppress baseline corticosterone levels in juvenile birds.  

PubMed

Mercury exposure has been associated with a wide variety of negative reproductive responses in birds, however few studies have examined the potential for chick impairment via the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis regulates corticosterone levels during periods of stress. We examined the relationship between baseline fecal corticosterone metabolite concentrations and mercury concentrations in down feathers of recently hatched (<3 days) and blood of older (15-37 days) Forster's tern (Sterna forsteri) chicks in San Francisco Bay, California. Baseline fecal corticosterone metabolite concentrations were negatively correlated with mercury concentrations in blood of older chicks (decreasing by 81% across the range of observed mercury concentrations) while accounting for positive correlations between corticosterone concentrations and number of fledgling chicks within the colony and chick age. In recently hatched chicks, baseline fecal corticosterone metabolite concentrations were weakly negatively correlated with mercury concentrations in down feathers (decreasing by 45% across the range of observed mercury concentrations) while accounting for stronger positive correlations between corticosterone concentrations and colony nest abundance and date. These results indicate that chronic mercury exposure may suppress baseline corticosterone concentrations in tern chicks and suggests that a juvenile bird's ability to respond to stress may be reduced via the downregulation of the HPA axis. PMID:22578153

Herring, Garth; Ackerman, Joshua T; Herzog, Mark P

2012-06-01

59

Mercury emission and dispersion models from soils contaminated by cinnabar mining and metallurgy.  

PubMed

The laboratory flux measurement system (LFMS) and dispersion models were used to investigate the kinetics of mercury emission flux (MEF) from contaminated soils. Representative soil samples with respect to total Hg concentration (26-9770 ?g g(-1)) surrounding a decommissioned mercury-mining area (Las Cuevas Mine), and a former mercury smelter (Cerco Metalúrgico de Almadenejos), in the Almadén mercury mining district (South Central Spain), were collected. Altogether, 14 samples were analyzed to determine the variation in mercury emission flux (MEF) versus distance from the sources, regulating two major environmental parameters comprising soil temperature and solar radiation. In addition, the fraction of the water-soluble mercury in these samples was determined in order to assess how MEF from soil is related to the mercury in the aqueous soil phase. Measured MEFs ranged from less than 140 to over 10,000 ng m(-2) h(-1), with the highest emissions from contaminated soils adjacent to point sources. A significant decrease of MEF was then observed with increasing distance from these sites. Strong positive effects of both temperature and solar radiation on MEF was observed. Moreover, MEF was found to occur more easily in soils with higher proportions of soluble mercury compared to soils where cinnabar prevails. Based on the calculated Hg emission rates and with the support of geographical information system (GIS) tools and ISC AERMOD software, dispersion models for atmospheric mercury were implemented. In this way, the gaseous mercury plume generated by the soil-originated emissions at different seasons was modeled. Modeling efforts revealed that much higher emissions and larger mercury plumes are generated in dry and warm periods (summer), while the plume is smaller and associated with lower concentrations of atmospheric mercury during colder periods with higher wind activity (fall). Based on the calculated emissions and the model implementation, yearly emissions from the "Cerco Metalúrgico de Almadenejos" decommissioned metallurgical precinct were estimated at 16.4 kg Hg y(-1), with significant differences between seasons. PMID:22037967

Llanos, Willians; Kocman, David; Higueras, Pablo; Horvat, Milena

2011-12-01

60

MERCURY DISTRIBUTION IN SOIL AROUND A LARGE COAL-FIRED POWER PLANT  

EPA Science Inventory

Seventy soil samples were collected on a radial grid employing sixteen evenly spaced radii and five logarithmically spaced circles, concentric around the Four Corners power plant. The soil samples were analyzed for total mercury using a Zeeman Atomic Absorption spectrophotometer....

61

MERCURY IN THE ENVIRONMENT  

EPA Science Inventory

Mercury is released from a variety of sources and exhibits a complicated chemistry. According to the Mercury Study Report to Congress, mercury fluxes and budgets in water, soil, and other media have increased by a factor of two to five over pre-industrial levels. The primary expo...

62

Decrease of soil fertility and release of mercury following deforestation in the Andean Amazon,  

E-print Network

Decrease of soil fertility and release of mercury following deforestation in the Andean Amazon erosion and degradation provoked by deforestation in the Amazon is a global concern, and recent studies propose a link between deforestation, soil erosion and the leaching of naturally occurring mercury (Hg

Long, Bernard

63

MERCURY RESIDUES IN SOIL AROUND A LARGE COAL-FIRED POWER PLANT  

EPA Science Inventory

Seventy soil samples were collected on a radial grid around the Four Corners power plant. The soil samples were analyzed for total mercury using a Zeeman atomic absorption spectrophotometer. Even though the plant emits 1-2% of all the mercury released by U.S. coal-fired utilities...

64

Comparison of immunoassay field tests and laboratory results for PCB, PAH, BTEX, and mercury contaminated soils  

Microsoft Academic Search

Immunoassay tests were used as in situ field screening tools for simultaneous assessment and remediation of soil contaminated with mercury and organics (polychlorinated biphenyls (PCB), polyaromatic hydrocarbons (PAH), and BTEX). Soil samples from approximately 200 sites including metering and compressor stations were investigated along gas pipelines. The suspected contamination originated from formerly used mercury manometers and pipeline liquids. An enzyme-linked

Hammes

1995-01-01

65

Soil and biomass mercury emissions during a prescribed fire in the Amazonian rain forest  

NASA Astrophysics Data System (ADS)

Mercury stored in forests can be volatilized to the atmosphere during fires. Many factors influence this process such as mercury concentration, vegetation loading and the soil temperature reached during the fire. We quantified mercury emissions from biomass and soil during a prescribed fire in Brazil using the difference in mercury burden in vegetation and soil before and after burning, and data were critically compared with those previously obtained in a similar experiment in another part of the Amazonia. The calculated mercury emission factor was 4.1 ± 1.4 g Hg ha-1, with the main part (78%) originating from litterfall and O-horizon, and only 14% associated with live biomass. When considering the fuel burned loading, the emission factor ranged from 40 to 53 ?g Hg kg-1. Data were also obtained on soil temperature profile and on Hg speciation in soil in an effort to relate these parameters to Hg emissions.

Melendez-Perez, Jose J.; Fostier, Anne H.; Carvalho, Joăo A.; Windmöller, Claudia C.; Santos, José C.; Carpi, Anthony

2014-10-01

66

Mercury  

Microsoft Academic Search

New findings on the environmental fate of Hg indicate that lakes can be contaminated by long distance transport on mercury vapor in the atmosphere and that higher levels of Me Hg in fish are associated with acidification of lakes and with the creation of hydroelectric reservoirs. Considerable progress has been made in the understanding of the disposition and metabolism of

Thomes W. Clarkson

1989-01-01

67

Egg mercury levels decline with the laying sequence in charadriiformes  

SciTech Connect

Whereas pollutants do not differ in concentration among eggs of one clutch in some bird species, in gulls, terns and grebes several organochlorines show intraclutch variation: Concentrations increase with the laying sequence. Heavy metals, however, are not so intensively studied with respect to intraclutch variation. In contrast to lead and cadmium, mercury is accumulated in great quantities in eggs. Variation in mercury levels between the eggs of one clutch were low compared to interclutch variability in the White-tailed Sea Eagle (Haliaeetus albicilla) and the Peregrine (Falco peregrinus). In gulls, however, intraclutch variation was significant and characterized by higher mercury levels in the first than in subsequently laid eggs, which is the opposite to the trend in organochlorine levels. In this paper, the author reports on investigations of intraclutch variation in mercury levels in three Charadriiform-species, Herring Gull, Common Tern and Oystercatcher (Haematopus ostralegus). The results confirm those previously reported in gulls and point to the importance of the egg in reducing the females' mercury burden. 23 refs, 2 tabs.

Becker, P.H. (Institut fuer Vogelforschung, Wilhelmshaven (Germany))

1992-05-01

68

Mercury and selected pesticide levels in fish and wildlife of Utah: I. levels of mercury, DDT, DDE, dieldrin and PCB in fish  

Microsoft Academic Search

Summary Levels of mercury and selected pesticides were determined in the muscle tissue of fish obtained from different regions in the state of Utah. The levels of mercury present were generally lower than the guideline limit (0.5 ppm) in most fish except those obtained from one localized area (Willard Bay Reservoir). Predators had the greatest accumulation of mercury. Only small

F. A. Smith; R. P. Sharma; R. I. Lynn; J. B. Low

1974-01-01

69

Subtask 1.17 - Subcritical Water Extraction of Mercury From Soils and Sediments  

SciTech Connect

The U.S. Environmental Protection Agency (EPA) "National Sediment Quality Survey" lists the top pollutants responsible for toxicity in watersheds as 1) PCBS (polychlorinated biphenyls), 2) mercury, and 3) other organics such as PAHs polycyclic aromatic hydrocarbons) and pesticides. In addition, these same pollutants are major contributors to chemical pollution on U.S. Department of Energy (DOE) and other contaminated sites (e.g., industrial sites and harbors). An ideal remediation method would allow cost-effective removal of both organic and mercury contamination using a single process. The Energy & Environmental Research Center (EERC) has demonstrated that controlling the temperature (and to a lesser extent, the pressure) of water can dramatically change its ability to extract organics and inorganic from matrices ranging from soils and sediments to waste sludges and coal. The dielectric constant of water can be changed from ca. 80 (a very polar solvent) to <5 (similar to a nonpolar organic solvent) by controlling the temperature (from ca. ambient to ca. 400oC) and pressure (from ea. 5 to 350 bar). The EERC has shown that hazardous organic pollutants such as pesticides, PAHs, and PCBS can be completely removed from soils, sludges, and sediments at temperatures (250"C) and pressures ( c 50 atrn) that are much milder than typically used for supercritical water processes (temperature > 374oC, pressure >221 atm). In addition, the process has been demonstrated to be particularly effective for samples containing very high levels of contaminants (e.g., parts per thousand). The EERC has also demonstrated that mercury can be extracted using supercritical water at much harsher conditions (400"C, and >300 atm). However, the removal of mercury from contaminated solids at the lower temperature and pressure conditions (e. g., 250"C, 50 atm) has not been investigated. If successful, this project will provide the basis for using hot/liquid water to extract both organic contaminants and mercury from contaminated solids in a single-step process.

Steven B. Hawthorne

1997-08-01

70

Total mercury and methylmercury levels in fish from hydroelectric reservoirs in Tanzania.  

PubMed

Total mercury (THg) and methylmercury (MeHg) levels have been determined in fish species representing various tropic levels in four major hydroelectric reservoirs (Mtera, Kidatu, Hale-Pangani, Nyumba ya Mungu) located in two distinct geographical areas in Tanzania. The Mtera and Kidatu reservoirs are located along the Great Ruaha River drainage basin in the southern central part of the country while the other reservoirs are located within the Pangani River basin in the north eastern part of Tanzania. Fish mercury levels ranged from 5 to 143 microg/kg (mean 40 microg/kg wet weight) in the Mtera Reservoir, and from 7 to 119 microg/kg (mean 21 microg/kg) in the Kidatu Reservoir downstream of the Great Ruaha River. The lowest THg levels, in the range 1-10 microg/kg (mean 5 microg/kg), were found in fish from the Nyumba ya Mungu (NyM) Reservoir, which is one of the oldest reservoirs in the country. Fish mercury levels in the Pangani and Hale mini-reservoirs, downstream of the NyM Reservoir, were in the order of 3-263 microg/kg, with an average level of 21 microg/kg. These THg levels are among the lowest to be reported in freshwater fish from hydroelectric reservoirs. Approximately 56-100% of the total mercury in the fish was methylmercury. Herbivorous fish species contained lower THg levels than the piscivorous species; this was consistent with similar findings in other fish studies. In general the fish from the Tanzanian reservoirs contained very low mercury concentrations, and differed markedly from fish in hydroelectric reservoirs of similar age in temperate and other regions, which are reported to contain elevated mercury concentrations. The low levels of mercury in the fish correlated with low background concentrations of THg in sediment and flooded soil (mean 2-8 microg/kg dry weight) in the reservoir surroundings. This suggested a relatively clean reservoir environment that has not been significantly impacted by mercury contamination from natural or anthropogenic sources. PMID:12663196

Ikingura, J R; Akagi, H

2003-03-20

71

Sulfur Polymer Stabilization/Solidification Treatability Study of Mercury Contaminated Soil from the Y-12 Site  

SciTech Connect

As a result of past operations, the Department of Energy’s (DOE) Oak Ridge Y-12 National Security Complex (Y-12 Plant) has extensive mercury-contamination in building structures, soils, storm sewer sediments, and stream sediments, which are a source of pollution to the local ecosystem. Because of mercury’s toxicity and potential impacts on human health and the environment, DOE continues to investigate and implement projects to support the remediation of the Y-12 site.URS and #9122;CH2M Oak Ridge LLC (UCOR) under its prime contract with DOE has cleanup responsibilities on the DOE Oak Ridge Reservation and is investigating potential mercury-contaminated soil treatment technologies through an agreement with Babcock and Wilcox (B and W) Y-12, the Y-12 operating contractor to DOE. As part of its investigations, UCOR has subcontracted with Brookhaven National Laboratory (BNL) to conduct laboratory-scale studies evaluating the applicability of the Sulfur Polymer Stabilization/Solidification (SPSS) process using surrogate and actual mixed waste Y-12 soils containing mercury (Hg) at 135, 2,000, and 10,000 ppm.SPSS uses a thermoplastic sulfur binder to convert Hg to stable mercury sulfide (HgS) and solidifies the chemically stable product in a monolithic solid final waste form to reduce dispersion and permeability. Formulations containing 40 – 60 dry wt% Y-12 soil were fabricated and samples were prepared in triplicate for Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP) testing by an independent laboratory. Those containing 50 and 60 wt% soil easily met the study criteria for maximum allowable Hg concentrations (47 and 1 ppb, respectively compared with the TCLP limit of 200 ppb Hg). The lowest waste loading of 40 wt% yielded TCLP Hg concentrations slightly higher (240 ppb) than the allowable limit. Since the Y-12 soil tended to form clumps, the improved leaching at higher waste loadings was probably due to reduction in particle size from friction of the soil mixing, which creates more surface area for chemical conversion. This was corroborated by the fact that the same waste loading pre-treated by ball milling to reduce particle size prior to SPSS processing yielded TCLP concentrations almost 30 times lower, and at 8.5 ppb Hg was well below EPA limits. Pre-treatment by ball milling also allowed a reduction in the time required for stabilization, thus potentially reducing total process times by 30%.Additional performance testing was conducted including measurement of compressive strength to confirm mechanical integrity and immersion testing to determine the potential impacts of storage or disposal under saturated conditions. For both surrogate and actual Y-12 treated soils, waste form compressive strengths ranged between 2,300 and 6,500 psi, indicating very strong mechanical integrity (a minimum of greater than 40 times greater than the NRC guidance for low-level radioactive waste). In general, compressive strength increases with waste loading as the soil acts as an aggregate in the sulfur concrete waste forms. No statistically significant loss in strength was recorded for the 30 and 40 wt% surrogate waste samples and only a minor reduction in strength was measured for the 43 wt% waste forms. The 30 wt% Y-12 soil did not show a significant loss in strength but the 50 wt% samples were severely degraded in immersion due to swelling of the clay soil. The impact on Hg leaching, if any, was not determined.

Kalb P.; Milian, L.; Yim, S. P.

2012-11-30

72

Accumulation of mercury and cadmium in rice from paddy soil near a mercury mine.  

PubMed

Paddy soil and rice (Oryza sativa L.) in the Wanshan mining area in Guizhou Province, China, have been contaminated by toxic trace metals such as cadmium (Cd) and mercury (Hg). The present study examined correlations between the types and physicochemical parameters of the soil and the contents of trace metals and the different forms of Hg in rice. The health risks of consuming contaminated rice from the Wanshan mining area were also assessed. Sequential extraction procedures were used to investigate the chemical behavior of Hg in the soil. The results showed that Hg and Cd were the most abundant trace metals in the Wanshan mining area. The toxic methylmercury (MeHg) content was substantial in brown rice, and the total amounts of total Hg (THg), diethylenetriaminepentaacetic acid-Hg, and water-soluble Hg varied in the rhizosphere and non-rhizosphere soils. An antagonistic interaction between Mn in brown rice, straw, and husk and MeHg in brown rice was also shown. An analysis of calculated dietary intake, target hazard quotients, and hazard indexes showed a potential risk of transferring Hg, MeHg, and Cd to humans when rice from the Wanshan mining area is consumed. Therefore, it must be concluded that consuming contaminated rice near the Wanshan mining area is a potential threat to human health. Environ Toxicol Chem 2014;33:2438-2447. © 2014 SETAC. PMID:25087518

Li, W C; Ouyang, Y; Ye, Z H

2014-11-01

73

Mercury in ambient air at the Oak Ridge Y-12 Plant, July 1986-December 1990.  

National Technical Information Service (NTIS)

At the Oak Ridge Y-12 Plant, airborne mercury levels are elevated over background levels as a result of mercury vaporization from mercury-contaminated soils, fugitive exhaust from Building 9201-4 (a former lithium isotope separation facility contaminated ...

R. R. Turner, M. A. Bogle, L. L. Heidel, L. M. McCain

1991-01-01

74

The Relationship between Adirondack Lake pH and Levels of Mercury in Yellow Perch  

Microsoft Academic Search

Levels of total mercury in yellow perch Perca flavescens from Adirondack lakes were studied in relation to characteristics of the lakes to determine why some lakes had fish with higher concentrations of mercury. Almost all mercury in fish is in the form of methylmercury, which can pose significant health hazards to humans who consume such fish. Fish mercury concentrations and

Donald Brown; Alexey Goncharov; Eric Paul; Howard Simonin; David O. Carpenter

2010-01-01

75

MERCURY IN MUSHROOMS AND SOIL FROM THE WIELU?SKA UPLAND IN SOUTH-CENTRAL POLAND  

Microsoft Academic Search

Concentrations of mercury were determined in the fruiting bodies of 15 species of higher mushrooms and underlying soil substrate collected from Wielu?ska Upland in northern part of Sandomierska Valley in south-central Poland in 1995. A total of 197 samples of caps, 197 stalks, 30 whole fruiting bodies and 227 soil (0–10 cm layer) were analyzed. Mean mercury concentrations in soil substrate

Jerzy Falandysz; Leszek Bielawski; Masahide Kawano; Andrzej Brzostowski; Krzysztof Chudzy?ski

2002-01-01

76

Canadian soil quality criteria for lead, copper, arsenic, cadmium and mercury  

SciTech Connect

National soil quality criteria for the protection of ecological receptors, including livestock and wildlife, are currently under development in Canada. Based on an evaluation of direct soil contact and soil and food ingestion pathways for sensitive species, soil quality criteria for lead, copper, arsenic, cadmium and mercury for three land use categories have been derived. The draft values, in mg/kg soil, for agricultural, residential/parkland, commercial/industrial land uses are: mercury, 4, 4, 30; copper, 62, 62, 100; cadmium, 10, 10, 27; lead, 70, 250, 400; arsenic, 17, 17, 26. Critical data requirements in developing soil quality criteria are also reviewed.

Gaudet, C.; Milne, D.; Teed, S.; Lin, J.; Raju, G.S.; Ouellet, S. [Environment Canada, Hull, Quebec (Canada)

1995-12-31

77

Survey of helium in soils and soil gases and mercury in soils at Roosevelt Hot Springs Known Geothermal Resource Area, Utah  

Microsoft Academic Search

The concentrations of helium and mercury in soils and of helium in soil gases were surveyed in part of the Roosevelt Hot Springs Known Geothermal Resource Area to see what relationship helium and mercury concentrations might have to geothermal features of the area. High concentrations of helium occurred over the producing geothermal field, in an area of high temperature gradients.

Hinkle

1980-01-01

78

Atmospheric mercury inputs in montane soils increase with elevation: evidence from mercury isotope signatures  

PubMed Central

The influence of topography on the biogeochemical cycle of mercury (Hg) has received relatively little attention. Here, we report the measurement of Hg species and their corresponding isotope composition in soil sampled along an elevational gradient transect on Mt. Leigong in subtropical southwestern China. The data are used to explain orography-related effects on the fate and behaviour of Hg species in montane environments. The total- and methyl-Hg concentrations in topsoil samples show a positive correlation with elevation. However, a negative elevation dependence was observed in the mass-dependent fractionation (MDF) and mass-independent fractionation (MIF) signatures of Hg isotopes. Both a MIF (?199Hg) binary mixing approach and the traditional inert element method indicate that the content of Hg derived from the atmosphere distinctly increases with altitude. PMID:24270081

Zhang, Hua; Yin, Run-sheng; Feng, Xin-bin; Sommar, Jonas; Anderson, Christopher W. N.; Sapkota, Atindra; Fu, Xue-wu; Larssen, Thorj?rn

2013-01-01

79

Mercury and plants in contaminated soils. 1: Uptake, partitioning, and emission to the atmosphere  

Microsoft Academic Search

The uptake, distribution, and subsequent emission of mercury to the atmosphere were investigated in five plant species (Lepidium latifolium [L.], Artemisia douglasiana [Bess in Hook], Caulanthus sp. [S. Watson], Fragaria vesca [L.], and Eucalyptus globulus [Labill]) with different ecological and physiological attributes. Transfer coefficients for mercury in the soil-plant system were calculated. Plant-to-atmosphere emissions of mercury were determined using a

Todd L. Leonard; M. S. Gustin; G. C. J. Fernandez; G. E. Jr. Taylor

1998-01-01

80

Mercury and plants in contaminated soils. 1: Uptake, partitioning, and emission to the atmosphere  

SciTech Connect

The uptake, distribution, and subsequent emission of mercury to the atmosphere were investigated in five plant species (Lepidium latifolium [L.], Artemisia douglasiana [Bess in Hook], Caulanthus sp. [S. Watson], Fragaria vesca [L.], and Eucalyptus globulus [Labill]) with different ecological and physiological attributes. Transfer coefficients for mercury in the soil-plant system were calculated. Plant-to-atmosphere emissions of mercury were determined using a controlled environment gas-exchange system and ranged from 10 to 93 mg/m{sup 2}/h in the light; emissions in the dark were an order of magnitude less. Transfer coefficients for mercury within the soil-plant system increased acropetally (root-to-leaf axis) by orders of magnitude. Estimated mercury emissions from plants in the Carson River Drainage Basin of Nevada over the growing season (0.5 mg/m{sup 2}) add to the previously reported soil mercury emissions (8.5 mg/m{sup 2}), resulting in total landscape emissions of 9 mg/m{sup 2}. For L. latifolium, 70% of the mercury taken up by the roots during the growing season was emitted to the atmosphere. For every one molecule of mercury retained in foliage of L. latifolium, 12 molecules of mercury were emitted. Within this arid ecosystem, mercury emissions are a dominant pathway of the mercury cycle. Plants function as conduits for the interfacial transport of mercury from the geosphere to the atmosphere, and this role is undervalued in models of the behavior of mercury in terrestrial exosystems and in the atmosphere on a global scale.

Leonard, T.L.; Gustin, M.S.; Fernandez, G.C.J. [Univ. of Nevada, Reno, NV (United States); Taylor, G.E. Jr. [George Mason Univ., Fairfax, VA (United States). Dept. of Biology

1998-10-01

81

High altitude artisanal small-scale gold mines are hot spots for Mercury in soils and plants.  

PubMed

Mercury releases from artisanal and small-scale gold mines (ASGM) condense and settle on plants, soils and water bodies. We collected soil and plant samples to add knowledge to the likely transfer of Hg from soils into plants and eventually predict Hg accumulation in livestock around ASGM in Bolivia. Mean contents of Hg in soils range from 0.5 to 48.6 mg Hg kg(-1) soil (5× to 60× more compared to control sites) and exceeded the soil Hg threshold levels in some European countries. The Hg contents ranged from 0.6 to 18 and 0.2 to 28.3 mg Hg kg(-1) leaf and root, respectively. The high Hg in Poaceae and Rosaceae may elevate Hg accumulation into the food chain because llama and alpaca solely thrive on these plants for food. Erosion of soils around ASGM in Bolivia contributes to the Hg contamination in lower reaches of the Amazon basin. PMID:23202639

Terán-Mita, Tania A; Faz, Angel; Salvador, Flor; Arocena, Joselito M; Acosta, Jose A

2013-02-01

82

Mercury Source Zone Identification using Soil Vapor Sampling and Analysis  

SciTech Connect

Development and demonstration of reliable measurement techniqes that can detect and help quantify the nature and extent of elemental mercury (Hg(0)) in the subsurface are needed to reduce certainties in the decision making process and increase the effectiveness of remedial actions. We conducted field tests at the Y-12 National Security Complex (NSC) in Oak Ridge, TN, to determine if sampling and analysis of Hg(0) vapors in the shallow subsurface (<0.3 m depth) can be used to as an indicator of the location and extent of Hg(0) releases in the subsurface. We constructed a rigid PVC pushprobe assembly, which was driven into the ground. Soil gas samples were collected through a sealed inner tube of the assembly and analyzed immediately in the field with a Lumex and/or Jerome Hg(0) analyzer. Time-series sampling showed that Hg vapor concentrations were fairly stable over time suggesting that the vapor phase Hg(0) was not being depleted and that sampling results were not dependent on the soil gas purge volume. Hg(0) vapor data collected at over 200 pushprobe locations at 3 different release sites correlated well to areas of known Hg(0) contamination. Vertical profiling of Hg(0) vapor concentrations conducted at 2 locations provided information on the vertical distribution of Hg(0) contamination in the subsurface. We concluded from our studies that soil gas sampling and analysis can be conducted rapidly and inexpensively at a large scale to help identify areas contaminated with Hg(0).

Watson, David B [ORNL] [ORNL; Miller, Carrie L [ORNL] [ORNL; Lester, Brian P [ORNL] [ORNL; Lowe, Kenneth Alan [ORNL] [ORNL; Southworth, George R [ORNL] [ORNL; Bogle, Mary Anna [ORNL] [ORNL; Liang, Liyuan [ORNL] [ORNL; Pierce, Eric M [ORNL] [ORNL

2014-01-01

83

A modified EK method with an I ? \\/I 2 lixiviant assisted and approaching cathodes to remedy mercury contaminated field soils  

Microsoft Academic Search

Wanshan mercury mine is the largest cinnabar deposit in Guizhou, China. Few effective methods had been achieved to remedy\\u000a Hg heavily contaminated field soils. In this paper, a modified EK method with approaching cathodes (AC-EK) and an I?\\/I2 lixiviant was described to remedy mercury-contaminated field soils near Wanshan mercury mine. Paddy Soil I and Paddy Soil\\u000a II were sampled and

Zhemin Shen; Jianda Zhang; Liya Qu; Zeqin Dong; Shenshen Zheng; Wenhua Wang

2009-01-01

84

[Correlation of fat content and dioxins, total mercury and methyl mercury levels in tuna].  

PubMed

In this study, we analyzed the concentrations of mercury and dioxins in tuna with various fat contents (akami; the leaner meat, Chutoro; the belly area of the tuna along the side of the fish between the akami and the otoro. Otoro; the fattiest portion of the tuna) in wild and farmed bluefin tuna and farmed southern bluefin tuna. In the three kinds of tuna, average dioxins concentrations in Akami, chutoro and otoro were 1.7, 4.7 and 9.6 pg TEQ/g, respectively. The dioxins concentration in all three regions of tuna was in direct proportion to the fat content. In the farmed bluefin tuna, the dioxins concentration was almost the same as that of the wild tuna, but differed from that of the farmed southern bluefin tuna. Average total mercury concentration based on wet weight in akami was 0.42 µg/g, being higher than the values of 0.36 µg/g of chutoro and 0.31 µg/g of otoro, and in inverse proportion to the fat content. In all three regions, the total mercury concentration of the wild bluefin tuna was equal to that of the farmed tuna. The total mercury concentration in the latter was two to three times higher than that of the farmed southern bluefin tuna. If the Japanese intake is one fin of tuna (80 g) a day, the daily intake levels of dioxins and methyl mercury can be estimated as 0.48-37 pg TEQ/kg bw and 0.21-0.90 µg/kg bw, respectively. PMID:21071911

Kawakami, Hiroyuki; Amakura, Yoshiaki; Tsutsumi, Tomoaki; Sasaki, Kumiko; Iketsu, Ayumi; Inasaki, Mizue; Kubota, Emi; Toyoda, Masatake

2010-01-01

85

Mercury  

NSDL National Science Digital Library

This site offers information on the planet Mercury. Some topics include: the atmosphere, surface, and interior of Mercury, missions to Mercury, recent discoveries, and myths and culture related to Mercury. There are also numerous pictures and additional websites to find more information.

2005-06-07

86

On-site mercury-contaminated soils remediation by using thermal desorption technology  

Microsoft Academic Search

In this study, the thermal desorption process was used to treat a mercury-contaminated soils in Taipei. A series of bench or pilot plant experiments were also performed the optimized operation condition. The results showed that the concentrations of residual mercury in all treated soils were below 2mg\\/kg, some even lower than 0.05mg\\/kg. The supernatant and exhaust gas stream of the

T. C. Chang; J. H. Yen

2006-01-01

87

Preparation and characterization of a soil reference material from a mercury contaminated site for comparability studies  

Microsoft Academic Search

The preparation and characterization of a soil reference material (SOIL-1) from a site polluted with mercury due to the past mercury mining in Idrija, Slovenia is reported. Homogeneity tests and intercomparison exercises for total (T-Hg) and methylmercury (MeHg) were performed. In addition, selective sequential extraction was applied for Hg fractionation, and multielemental analyses were performed by k0 standardization neutron activation

David Kocman; Nicolas S. Bloom; Hirokatso Akagi; Kevin Telmer; Lars Hylander; Vesna Fajon; Vesna Jereb; Radojko Ja?imovi?; Borut Smodiš; Justinian R. Ikingura; Milena Horvat

2006-01-01

88

Mercury in soil and perennial plants in a mining-affected urban area from Northwestern Romania.  

PubMed

The mercury (Hg) concentrations were evaluated in soils and perennial plants sampled in four districts of Baia Mare city, a historical mining and ore processing center in Northwestern Romania. The results showed that the Hg concentration exceeded the guideline value of 1.0 mg kg(-1) dry weight (dw) established by the Romanian Legislation, in 24 % of the analyzed soil samples, while the median Hg concentration (0.70 mg kg(-1) dw) was lower than the guideline value. However, Hg content in soil was generally higher than typical values in soils from residential and agricultural areas of the cities all over the world. The median Hg concentration was 0.22 mg kg(-1) dw in the perennial plants, and exceeded the maximum level of Hg (0.10 mg kg(-1)) established by European Directive 2002/32/EC for plants used in animal feed in order to prevent its transfer and further accumulation in the higher levels of food chain. No significant correlations were found between soil Hg and other analyzed metals (Cd, Cu, Pb, Zn) resulted from the non-ferrous smelting activities, probably due to the different physicochemical properties, that led to different dispersion patterns. PMID:22375545

Senil?, Marin; Levei, Erika A; Senil?, L?crimioara R; Oprea, Gabriela M; Roman, Cecilia M

2012-01-01

89

Lead and mercury levels in raccoons from Macon County, Alabama  

SciTech Connect

Heavy metal contamination in the environment has become a major concern of the scientific community. The ubiquitous present of heavy metals such as lead, mercury, and cadmium in wildlife animals has been reported. Although the understanding of the full significance of these metals is incomplete, it is known that some species contain concentrations of metals proportional to the levels present in their environments. Thus, wild animals can be used as biological indicators of environmental concentrations of metals. The behavior, omnivorous feeding habits, and adaptability of raccoons (Procyon lotor) qualify this animal as a useful indicator of environmental pollution. The purpose of this paper was to report some preliminary observations on lead and mercury levels in raccoons from Macon County, Alabama, a potential indicator species for wildlife. 19 refs., 3 tabs.

Khan, A.T.; Thompson, S.J. [Tuskegee Univ., AL (United States); Mieike, H.W. [Xavier Univ. of Louisiana, New Orleans, LA (United States)

1995-06-01

90

Quantifying the effects of soil temperature, moisture and sterilization on elemental mercury formation in boreal soils.  

PubMed

Soils are a source of elemental mercury (Hg(0)) to the atmosphere, however the effects of soil temperature and moisture on Hg(0) formation is not well defined. This research quantifies the effect of varying soil temperature (278-303 K), moisture (15-80% water filled pore space (WFPS)) and sterilization on the kinetics of Hg(0) formation in forested soils of Nova Scotia, Canada. Both, the logarithm of cumulative mass of Hg(0) formed in soils and the reduction rate constants (k values) increased with temperature and moisture respectively. Sterilizing soils significantly (p < 0.05, n = 10) decreased the percent of total Hg reduced to Hg(0). We describe the fundamentals of Hg(0) formation in soils and our results highlight two key processes: (i) a fast abiotic process that peaks at 45% WFPS and depletes a small pool of Hg(0) and; (ii) a slower, rate limiting biotic process that generates a large pool of reducible Hg(II). PMID:25016467

Pannu, Ravinder; Siciliano, Steven D; O'Driscoll, Nelson J

2014-10-01

91

Strong positive associations between seafood, vegetables, and alcohol with blood mercury and urinary arsenic levels in the Korean adult population.  

PubMed

Blood mercury and urinary arsenic levels are more than fivefold greater in the Korean population compared with those of the United States. This may be related to the foods people consumed. Therefore, we examined the associations between food categories and mercury and arsenic exposure in the Korean adult population. Data regarding nutritional, biochemical, and health-related parameters were obtained from a cross-sectional study, the 2008-2009 Korean National Health and Nutrition Examination Survey (3,404 men and women age ? 20 years). The log-transformed blood mercury and urinary arsenic levels were regressed against the frequency tertiles of each food group after covariate adjustment for sex, age, residence area, education level, smoking status, and drinking status using food-frequency data. Blood mercury levels in the high consumption groups compared to the low consumption groups were elevated by about 20 percents with salted fish, shellfish, whitefish, bluefish, and alcohol, and by about 9-14 percents with seaweeds, green vegetables, fruits and tea, whereas rice did not affect blood mercury levels. Urinary arsenic levels were markedly increased with consumption of rice, bluefish, salted fish, shellfish, whitefish, and seaweed, whereas they were moderately increased with consumption of grains, green and white vegetables, fruits, coffee, and alcohol. The remaining food categories tended to lower these levels only minimally. In conclusion, the typical Asian diet, which is high in rice, salted fish, shellfish, vegetables, alcoholic beverages, and tea, may be associated with greater blood mercury and urinary arsenic levels. This study suggests that mercury and arsenic contents should be monitored and controlled in soil and water used for agriculture to decrease health risks from heavy-metal contamination. PMID:23011092

Park, Sunmin; Lee, Byung-Kook

2013-01-01

92

Spatial distribution of mercury in the surface soils of the urban areas, arak, iran.  

PubMed

This study assessed the baseline concentrations and spatial distribution of total mercury (Hg) in urban soils of the city of Arak, Iran. Concentrations of Hg were determined in soil collected from urban areas, and the spatial distribution was analyzed using the semivariogram approach in geostatistical technology. Mercury in soil ranged from 66.3 to 581 µg/kg. The experimental variogram of soil mercury concentrations was best-fitted by a spherical model. A spatial distribution map revealed that Hg concentration showed decreasing trends from south to north, west to east and center to suburb. Overall, the results showed that Hg concentrations in urban soils of Arak may be considered medium or low. PMID:25344748

Solgi, Eisa; Esmaili-Sari, Abbas; Riyahi-Bakhtiari, Alireza

2014-12-01

93

REMOVAL OF MERCURY FROM CONTAMINATED SOILS AT THE PAVLODAR CHEMICAL PLANT.  

SciTech Connect

Soils beneath and adjacent to the Pavlodar Chemical Plant in Kazakhstan have been contaminated with elemental mercury as a result of chlor alkali processing using mercury cathode cell technology. The work described in this paper was conducted in preparation for a demonstration of a technology to remove the mercury from the contaminated soils using a vacuum assisted thermal distillation process. The process can operate at temperatures from 250-500 C and pressures of 0.13kPa-1.33kPa. Following vaporization, the mercury vapor is cooled, condensed and concentrated back to liquid elemental mercury. It will then be treated using the Sulfur Polymer Stabilization/Solidification process developed at Brookhaven National Laboratory as described in a companion paper at this conference. The overall project objectives include chemical and physical characterization of the contaminated soils, study of the influence of the soil's physical-chemical and hydro dynamical characteristics on process parameters, and laboratory testing to optimize the mercury sublimation rate when heating in vacuum. Based on these laboratory and pilot-scale data, a full-scale production process will be designed for testing. This paper describes the soil characterization. This work is being sponsored by the International Science and Technology Center.

KHRAPUNOV, V. YE.; ISAKOVA, R.A.; LEVINTOV, B.L.; KALB, P.D.; KAMBEROV, I.M.; TREBUKHOV, A.

2004-09-25

94

Glutathione level after long-term occupational elemental mercury exposure  

SciTech Connect

Many in vitro and in vivo studies have elucidated the interaction of inorganic mercury (Hg) and glutathione. However, human studies are limited. In this study, we investigated the potential effects of remote long-term intermittent occupational elemental Hg vapour (Hg{sup o}) exposure on erythrocyte glutathione levels and some antioxidative enzyme activities in ex-mercury miners in the period after exposure. The study included 49 ex-mercury miners divided into subgroups of 28 still active, Hg{sup o}-not-exposed miners and 21 elderly retired miners, and 41 controls, age-matched to the miners subgroup. The control workers were taken from 'mercury-free works'. Reduced glutathione (GSH) and oxidized disulphide glutathione (GSSG) concentrations in haemolysed erythrocytes were determined by capillary electrophoresis, while total glutathione (total GSH) and the GSH/GSSG ratio were calculated from the determined values. Catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities in erythrocytes were measured using commercially available reagent kits, while urine Hg (U-Hg) concentrations were determined by cold vapour atomic absorption (CVAAS). No correlation of present U-Hg levels, GSH, GSSG, and antioxidative enzymes with remote occupational biological exposure indices were found. The mean CAT activity in miners and retired miners was significantly higher (p<0.05) than in the controls. No differences in mean GPx activity among the three groups were found, whereas the mean GR activity was significantly higher (p<0.05) in miners than in retired miners. The mean concentrations of GSH (mmol/g Hb) in miners (13.03{+-}3.71) were significantly higher (p<0.05) than in the control group (11.68{+-}2.66). No differences in mean total GSH, GSSG levels, and GSH/GSSG ratio between miners and controls were found. A positive correlation between GSSG and present U-Hg excretion (r=0.41, p=0.001) in the whole group of ex-mercury miners was observed. The significantly lower GSH level (p<0.05) determined in the group of retired miners (9.64{+-}1.45) seems to be age-related (r=-0.39, p=0.001). Thus, the moderate but significantly increased GSH level, GR and CAT activity in erythrocytes in the subgroup of miners observed in the period after exposure to Hg{sup o} could be an inductive and additive response to maintain the balance between GSH and antioxidative enzymes in interaction with the Hg body burden accumulated during remote occupational exposure, which does not represent a severely increased oxidative stress.

Kobal, Alfred Bogomir [University Medical Centre Ljubljana, Institute of Clinical Chemistry and Biochemistry, Njegoseva 4, SI-1525 Ljubljana (Slovenia)], E-mail: abkobal@volja.net; Prezelj, Marija [University Medical Centre Ljubljana, Institute of Clinical Chemistry and Biochemistry, Njegoseva 4, SI-1525 Ljubljana (Slovenia); Horvat, Milena [Department of Environmental Sciences, Jozef Stefan Institute, Ljubljana (Slovenia); Krsnik, Mladen [University Medical Centre Ljubljana, Institute of Clinical Chemistry and Biochemistry, Njegoseva 4, SI-1525 Ljubljana (Slovenia); Gibicar, Darija [Department of Environmental Sciences, Jozef Stefan Institute, Ljubljana (Slovenia); Osredkar, Josko [University Medical Centre Ljubljana, Institute of Clinical Chemistry and Biochemistry, Njegoseva 4, SI-1525 Ljubljana (Slovenia)

2008-05-15

95

Selenium modulates mercury uptake and distribution in rice (Oryza sativa L.), in correlation with mercury species and exposure level.  

PubMed

Rice cultured in Hg- and/or Se-contaminated fields is an important food source of human Hg/Se intake. There are elevated Hg and Se levels in the soil of the Wanshan District, Guizhou Province. Here we attempted to explore how a Hg antagonist, Se, modulates the absorption and accumulation of inorganic mercury (IHg) and methylmercury (MeHg) in rice. The effects of Se on the content and transportation of Hg in hydroponic and soil cultured rice plants were examined. The results show that IHg mainly accumulated in the rice roots, but some also accumulated in the rice grain. In comparison to IHg, MeHg can be concentrated in the rice grain, and the proportion of MeHg in the rice grain may account for above 40% of the total Hg. Se can protect against Hg phytotoxicity in rice and inhibit IHg accumulation in rice tissues, but was not remarkable for MeHg at a low dosage exposure level in this study. These discrepancies imply mechanistic differences between IHg and MeHg absorption and accumulation in rice. This study illustrates that Se plays an important role in modulating Hg uptake, transportation and accumulation in rice. Therefore, Se is considered to be a naturally existing element that effectively reduces Hg accumulation in rice, which may have significant implications for food safety. PMID:25142173

Zhao, Jiating; Li, Yufeng; Li, Yunyun; Gao, Yuxi; Li, Bai; Hu, Yi; Zhao, Yuliang; Chai, Zhifang

2014-10-01

96

Mercury  

MedlinePLUS

... Releases and Spills Fish Consumption Advice Consumer Products Mercury News September 2014 – EPA has proposed effluent limitation ... 2014 press release News Archive Minimata Convention on Mercury EPA web page on the Minimata Convention United ...

97

Mercury  

NSDL National Science Digital Library

This lithograph shows mosaic images of Mercury, captured by the Mariner 10 spacecraft. The images are accompanied by a brief description and history, some statistical facts, and a list of significant dates in the exploration of Mercury.

98

Risk, Mercury Levels, and Birds: Relating Adverse Laboratory Effects to Field Biomonitoring  

Microsoft Academic Search

There is an abundance of field data on levels of mercury in a variety of organisms and there are a number of studies that demonstrate the adverse effects of mercury on laboratory animals, but few studies examine the relationship between the two. Thus it is often difficult to determine the ecological relevance of mercury concentrations found in nature, or to

Joanna Burger; Michael Gochfeld

1997-01-01

99

Biogeochemical factors affecting mercury methylation rate in two contaminated floodplain soils  

Microsoft Academic Search

An automated biogeochemical microcosm system allowing controlled variation of redox potential (EH) in soil suspensions was used to assess the effect of various factors on the mobility of mercury (Hg) as well as on the methylation of Hg in two contaminated floodplain soils with different Hg concentrations (approximately 5 mg kg-1 Hg and >30 mg kg-1 Hg). The experiment was

T. Frohne; J. Rinklebe; U. Langer; G. Du Laing; S. Mothes; R. Wennrich

2011-01-01

100

Characteristics of mercury exchange flux between soil and air in the heavily air-polluted area, eastern Guizhou, China  

NASA Astrophysics Data System (ADS)

To investigate the characteristics of mercury exchange between soil and air in the heavily air-polluted area, total gaseous mercury (TGM) concentration in air and Hg exchange flux were measured in Wanshan Hg mining area (WMMA) in November, 2002 and July-August, 2004. The results showed that the average TGM concentrations in the ambient air (17.8-1101.8 ng m -3), average Hg emission flux (162-27827 ng m -2 h -1) and average Hg dry deposition flux (0-9434 ng m -2 h -1) in WMMA were 1-4 orders of magnitude higher than those in the background area. It is said that mercury-enriched soil is a significant Hg source of the atmosphere in WMMA. It was also found that widely distributed roasted cinnabar banks are net Hg sources of the atmosphere in WMMA. Relationships between mercury exchange flux and environmental parameters were investigated. The results indicated that the rate of mercury emission from soil could be accelerated by high total soil mercury concentration and solar irradiation. Whereas, highly elevated TGM concentrations in the ambient air can restrain Hg emission from soil and even lead to strongly atmospheric Hg deposition to soil surface. A great amount of gaseous mercury in the heavily polluted atmosphere may cycle between soil and air quickly and locally. Vegetation can inhibit mercury emission from soil and are important sinks of atmospheric mercury in heavily air-polluted area.

Wang, Shaofeng; Feng, Xinbin; Qiu, Guangle; Fu, Xuewu; Wei, Zhongqing

101

Mercury and selected pesticide levels in fish and wildlife of Utah: II. levels of mercury, DDT, DDE, dieldrin and PCB in chukars, pheasants and waterfowl  

Microsoft Academic Search

Summary Levels of mercury and selected pesticides were determined in muscle tissue of chukars, pheasants and waterfowl collected from various regions within the state of Utah. None of the chukar tissue 6% of the pheasant tissue and 4% of the waterfowl tissue analyzed contained mercury concentrations greater than the FDA limit of 0.5 ppm. None of the chukars or pheasants

F. A. Smith; R. P. Sharma; R. I. Lynn; J. B. Low

1974-01-01

102

Relationship between dietary mercury intake and blood mercury level in Korea.  

PubMed

This study was performed to evaluate the effect of dietary factors for mercury exposure by comparing with blood mercury concentration. Study population consisted of 1,866 adults (839 men and 1,027 women) in randomly-selected 30 districts in southeast Korea. Dietary mercury intake was calculated from food frequency questionnaire (FFQ) on seafood items and 24 hr recall record. Blood mercury concentration was measured with atomic absorption spectrometry. Mean age of the subjects was 43.5 ± 14.6 yr. The FFQ showed that mercury-laden fish (tuna, shark) and frequently-eating fish (squid, belt fish, mackerel) were important in mercury intake from fish species. The recall record suggested that fish and shellfish was a highest group (63.1%) of mercury intake and had a wide distribution in the food groups. In comparison with the blood mercury concentration, age group, sex, household income, education, drinking status and coastal area were statistically significant (P < 0.001). In multiple regression analysis, coefficient from the FFQ (? = 0.003) had greater effect on the blood mercury than the recall record (? = 0.002), but the effect was restricted (adjusted R(2) = 0.234). Further studies with more precise estimation of dietary mercury intake were required to evaluate the risk for mercury exposure by foods and assure risk communication with heavily-exposed group. PMID:24550642

You, Chang-Hun; Kim, Byoung-Gwon; Kim, Yu-Mi; Lee, Sang-Ah; Kim, Rock-Bum; Seo, Jeong-Wook; Hong, Young-Seoub

2014-02-01

103

STATE FISH SURVEY FINDS MERCURY LEVELS DOWN By Alex Breitler  

E-print Network

as mercury. Some mercury occurs naturally, and some has persisted in the environment since the Gold Rush days, when it was used to extract gold from rocks. Some is also deposited into our waterways from the air

104

A laboratory based experimental study of mercury emission from contaminated soils in the River Idrijca catchment  

NASA Astrophysics Data System (ADS)

Results obtained by a laboratory flux measurement system (LFMS) focused on investigating the kinetics of the mercury emission flux (MEF) from contaminated soils of the Idrija Hg-mine region, Slovenia are presented. Representative soil samples with respect to total Hg concentrations (4-417 ?g g-1) and land cover (forest, meadow and alluvial soil) alongside the River Idrijca were analysed to determine the variation in MEF versus distance from the source, regulating three major environmental parameters comprising soil temperature, soil moisture and solar radiation. MEFs ranged from less than 2 to 530 ng m-2 h-1, with the highest emissions from contaminated alluvial soils and soils near the mining district in the town of Idrija. A significant decrease of MEF was then observed with increasing distance from these sites. The results revealed a strong positive effect of all three parameters investigated on momentum MEF. The light-induced flux was shown to be independent of the soil temperature, while the soil aqueous phase seems to be responsible for recharging the pool of mercury in the soil available for both the light- and thermally-induced flux. The overall flux response to simulated environmental conditions depends greatly on the form of Hg in the soil. Higher activation energies are required for the overall process to occur in soils where insoluble cinnabar prevails compared to soils where more mobile Hg forms and forms available for transformation processes are dominant.

Kocman, D.; Horvat, M.

2009-11-01

105

A laboratory based experimental study of mercury emission from contaminated soils in the River Idrijca catchment  

NASA Astrophysics Data System (ADS)

Results obtained by a laboratory flux measurement system (LFMS) focused on investigating the kinetics of the mercury emission flux (MEF) from contaminated soils of the Idrija Hg-mine region, Slovenia are presented. Representative soil samples with respect to total Hg concentrations (4-417 ?g g-1) and land cover (forest, meadow and alluvial soil) alongside the River Idrijca were analysed to determine the variation in MEF versus distance from the source, regulating three major environmental parameters comprising soil temperature, soil moisture and solar radiation. MEFs ranged from less than 2 to 530 ng m-2 h-1, with the highest emissions from contaminated alluvial soils and soils near the mining district in the town of Idrija. A significant decrease of MEF was then observed with increasing distance from these sites. The results revealed a strong positive effect of all three parameters investigated on momentum MEF. The light-induced flux was shown to be independent of the soil temperature, while the soil aqueous phase seems to be responsible for recharging the pool of mercury in the soil available for both the light- and thermally-induced flux. The overall flux response to simulated environmental conditions depends greatly on the form of Hg in the soil. Higher activation energies are required for the overall process to occur in soils where insoluble cinnabar prevails compared to soils where more mobile Hg forms and forms available for transformation processes are dominant.

Kocman, D.; Horvat, M.

2010-02-01

106

USEPA'S RESEARCH PROGRAM ON REMEDIATION AND CONTAINMENT OF ARSENIC AND MERCURY IN SOILS, INDUSTRIAL WASTES, AND GROUNDWATER  

EPA Science Inventory

In the U.S. and around the world, mercury and arsenic contaminated soils, industrial wastes, and groundwater are difficult to effectively and cheaply remediate and contain. Mercury is a serious health concern and has been identified as a contaminant in the air, soil, sediment, su...

107

Volcanism and soil mercury on Mars - Consequences for terrestrial microorganisms  

NASA Technical Reports Server (NTRS)

An earth-Mars depletion formula proposed by Anders and Owen for volatiles is used to calculate a range of putative Hg levels for Martian volcanic soils based upon analyzed samples from Hawaii. The range is about 50-150 microgram per kg. When applied either in conventional or special media (e.g., basalt powder), these levels of Hg are effective inhibitors of the growth of earth microorganisms. Taken together with other hostile chemical and physical factors, volcanic toxicants would appear to provide a further deterrent to the accidental establishment of terrestrial microbiota on Mars.

Siegel, B. Z.; Siegel, S. M.

1978-01-01

108

Bench-scale vitrification studies with Savannah River Site mercury contaminated soil  

Microsoft Academic Search

The Savannah River Technology Center (SRTC) has been charted by the Department of Energy (DOE)--Office of Technology Development (OTD) to investigate vitrification technology for the treatment of Low Level Mixed Wastes (LLMW). In fiscal year 1995, mercury containing LLMW streams were targeted. In order to successfully apply vitrification technology to mercury containing LLMW, the types and quantities of glass forming

C. A. Cicero; D. F. Bickford

1995-01-01

109

Mercury and Selenium in Fish from the Savannah River: Species, Trophic Level, and Locational Differences  

Microsoft Academic Search

Levels of contaminants in fish are of considerable interest because of potential effects on the fish themselves, as well as on other organisms that consume them. In this article we compare the mercury levels in muscle tissue of 11 fish species from the Savannah River, as well as selenium levels because of its known protective effect against mercury toxicity. We

Joanna Burger; Karen F. Gaines; C. Shane Boring; Warren L. Stephens; Joel Snodgrass; Michael Gochfeld

2001-01-01

110

Soil radon and elemental mercury distribution and relation to magmatic resurgence at long valley caldera.  

PubMed

The response of a large geothermal system to magmatic resurgence was analyzed by a survey of soil gas radon and elemental mercury at 600 sites in the silicic Long Valley Caldera, California. The broad geochemical anomaly over the caldera has superimposed on it a small zone of pronounced radon enrichment and mercury depletion coincident with the surface projection of a postulated dike of rising magma. Soil gas geochemistry studies can complement traditional geophysical and geodetical methods in the evaluation of potential volcanic eruption hazards. PMID:17732438

Williams, S N

1985-08-01

111

Effects of low dietary levels of methyl mercury on mallard reproduction  

USGS Publications Warehouse

Mallard ducks were fed a control diet or a diet containing 0.5 ppm or 3 ppm mercury (as methylmercury dicyandiamide). Health of adults and reproductive success were studied. The dietary level of 3 ppm mercury had harmful effects on reproduction, although it did not appear to affect the health of the adults during the 12 months of dosage. Ducks that were fed the diet containing 0.5 ppm mercury reproduced as well as controls, and ducklings from parents fed 0.5 ppm mercury grew faster in the first week of life than did controls....The greatest harm to reproduction associated with the diet containing 3 ppm mercury was an increase in duckling mortality, but reduced egg laying and increased embryonic mortality also occurred....During the peak of egg laying, eggs laid by controls tended to be heavier than eggs laid by ducks fed either level of mercury; however, there seemed to be no eggshell thinning associated with mercury treatment. Levels of mercury reached about 1 ppm in eggs from ducks fed a dietary dosage of 0.5 ppm mercury and between 6 and 9 ppm in the eggs from ducks fed 3 ppm mercury.

Heinz, G.

1974-01-01

112

An Assessment of health risk associated with mercury in soil and sediment from East Fork Poplar Creek, Oak Ridge, Tennessee. Final report  

SciTech Connect

This report presents results from a study conducted to determine the toxicity of Mercury in soils sediments samples. Mice were fed via diet, soils and sediment, from various locations along the East Fork Poplar creek. Tissue distribution of pollutants was determined at various intervals. The tissue level relative to toxicity was used to determine the effect of a complex matrix on the gastrointestinal absorption and tissue distribution of the pollutants (other pollutants included cadmium and selenium).

Revis, N.; Holdsworth, G.; Bingham, G.; King, A.; Elmore, J.

1989-04-01

113

Gaseous mercury fluxes from forest soils in response to forest harvesting intensity: A field manipulation experiment.  

PubMed

Forest harvesting leads to changes in soil moisture, temperature and incident solar radiation, all strong environmental drivers of soil-air mercury (Hg) fluxes. Whether different forest harvesting practices significantly alter Hg fluxes from forest soils is unknown. We conducted a field-scale experiment in a northern Minnesota deciduous forest wherein gaseous Hg emissions from the forest floor were monitored after two forest harvesting prescriptions, a traditional clear-cut and a clearcut followed by biomass harvest, and compared to an un-harvested reference plot. Gaseous Hg emissions were measured in quadruplicate at four different times between March and November 2012 using Teflon dynamic flux chambers. We also applied enriched Hg isotope tracers and separately monitored their emission in triplicate at the same times as ambient measurements. Clearcut followed by biomass harvesting increased ambient Hg emissions the most. While significant intra-site spatial variability was observed, Hg emissions from the biomass harvested plot (180±170ngm(-2)d(-1)) were significantly greater than both the traditional clearcut plot (-40±60ngm(-2)d(-1)) and the un-harvested reference plot (-180±115ngm(-2)d(-1)) during July. This difference was likely a result of enhanced Hg(2+) photoreduction due to canopy removal and less shading from downed woody debris in the biomass harvested plot. Gaseous Hg emissions from more recently deposited Hg, as presumably representative of isotope tracer measurements, were not significantly influenced by harvesting. Most of the Hg tracer applied to the forest floor became sequestered within the ground vegetation and debris, leaf litter, and soil. We observed a dramatic lessening of tracer Hg emissions to near detection levels within 6months. As post-clearcutting residues are increasingly used as a fuel or fiber resource, our observations suggest that gaseous Hg emissions from forest soils will increase, although it is not yet clear for how long such an effect will persist. PMID:24993512

Mazur, M; Mitchell, C P J; Eckley, C S; Eggert, S L; Kolka, R K; Sebestyen, S D; Swain, E B

2014-10-15

114

Unified Science Information Model for SoilSCAPE using the Mercury Metadata Search System  

NASA Astrophysics Data System (ADS)

SoilSCAPE (Soil moisture Sensing Controller And oPtimal Estimator) introduces a new concept for a smart wireless sensor web technology for optimal measurements of surface-to-depth profiles of soil moisture using in-situ sensors. The objective is to enable a guided and adaptive sampling strategy for the in-situ sensor network to meet the measurement validation objectives of spaceborne soil moisture sensors such as the Soil Moisture Active Passive (SMAP) mission. This work is being carried out at the University of Michigan, the Massachusetts Institute of Technology, University of Southern California, and Oak Ridge National Laboratory. At Oak Ridge National Laboratory we are using Mercury metadata search system [1] for building a Unified Information System for the SoilSCAPE project. This unified portal primarily comprises three key pieces: Distributed Search/Discovery; Data Collections and Integration; and Data Dissemination. Mercury, a Federally funded software for metadata harvesting, indexing, and searching would be used for this module. Soil moisture data sources identified as part of this activity such as SoilSCAPE and FLUXNET (in-situ sensors), AirMOSS (airborne retrieval), SMAP (spaceborne retrieval), and are being indexed and maintained by Mercury. Mercury would be the central repository of data sources for cal/val for soil moisture studies and would provide a mechanism to identify additional data sources. Relevant metadata from existing inventories such as ORNL DAAC, USGS Clearinghouse, ARM, NASA ECHO, GCMD etc. would be brought in to this soil-moisture data search/discovery module. The SoilSCAPE [2] metadata records will also be published in broader metadata repositories such as GCMD, data.gov. Mercury can be configured to provide a single portal to soil moisture information contained in disparate data management systems located anywhere on the Internet. Mercury is able to extract, metadata systematically from HTML pages or XML files using a variety of methods including OAI-PMH [3]. The Mercury search interface then allows users to perform simple, fielded, spatial and temporal searches across a central harmonized index of metadata. Mercury supports various metadata standards including FGDC, ISO-19115, DIF, Dublin-Core, Darwin-Core, and EML. This poster describes in detail how Mercury implements the Unified Science Information Model for Soil moisture data. References: [1]Devarakonda R., et al. Mercury: reusable metadata management, data discovery and access system. Earth Science Informatics (2010), 3(1): 87-94. [2]Devarakonda R., et al. Daymet: Single Pixel Data Extraction Tool. http://daymet.ornl.gov/singlepixel.html (2012). Last Accesses 10-01-2013 [3]Devarakonda R., et al. Data sharing and retrieval using OAI-PMH. Earth Science Informatics (2011), 4(1): 1-5.

Devarakonda, Ranjeet; Lu, Kefa; Palanisamy, Giri; Cook, Robert; Santhana Vannan, Suresh; Moghaddam, Mahta Clewley, Dan; Silva, Agnelo; Akbar, Ruzbeh

2013-12-01

115

The influence of depth on mercury levels in pelagic fishes and their prey  

PubMed Central

Mercury distribution in the oceans is controlled by complex biogeochemical cycles, resulting in retention of trace amounts of this metal in plants and animals. Inter- and intra-specific variations in mercury levels of predatory pelagic fish have been previously linked to size, age, trophic position, physical and chemical environmental parameters, and location of capture; however, considerable variation remains unexplained. In this paper, we focus on differences in ecology, depth of occurrence, and total mercury levels in 9 species of commercially important pelagic fish (Thunnus obesus, T. albacares, Katsuwonus pelamis, Xiphias gladius, Lampris guttatus, Coryphaena hippurus, Taractichthys steindachneri, Tetrapturus audax, and Lepidocybium flavobrunneum) and in numerous representatives (fishes, squids, and crustaceans) of their lower trophic level prey sampled from the central North Pacific Ocean. Results indicate that total mercury levels of predatory pelagic fishes and their prey increase with median depth of occurrence in the water column and mimic concentrations of dissolved organic mercury in seawater. Stomach content analysis results from this study and others indicate a greater occurrence of higher-mercury containing deeper-water prey organisms in the diets of the deeper-ranging predators, X. gladius, T. obesus, and L. guttatus. While present in trace amounts, dissolved organic mercury increases with depth in the water column suggesting that the mesopelagic habitat is a major entry point for mercury into marine food webs. These data suggest that a major determinant of mercury levels in oceanic predators is their depth of forage. PMID:19666614

Choy, C. Anela; Popp, Brian N.; Kaneko, J. John; Drazen, Jeffrey C.

2009-01-01

116

The influence of depth on mercury levels in pelagic fishes and their prey.  

PubMed

Mercury distribution in the oceans is controlled by complex biogeochemical cycles, resulting in retention of trace amounts of this metal in plants and animals. Inter- and intra-specific variations in mercury levels of predatory pelagic fish have been previously linked to size, age, trophic position, physical and chemical environmental parameters, and location of capture; however, considerable variation remains unexplained. In this paper, we focus on differences in ecology, depth of occurrence, and total mercury levels in 9 species of commercially important pelagic fish (Thunnus obesus, T. albacares, Katsuwonus pelamis, Xiphias gladius, Lampris guttatus, Coryphaena hippurus, Taractichthys steindachneri, Tetrapturus audax, and Lepidocybium flavobrunneum) and in numerous representatives (fishes, squids, and crustaceans) of their lower trophic level prey sampled from the central North Pacific Ocean. Results indicate that total mercury levels of predatory pelagic fishes and their prey increase with median depth of occurrence in the water column and mimic concentrations of dissolved organic mercury in seawater. Stomach content analysis results from this study and others indicate a greater occurrence of higher-mercury containing deeper-water prey organisms in the diets of the deeper-ranging predators, X. gladius, T. obesus, and L. guttatus. While present in trace amounts, dissolved organic mercury increases with depth in the water column suggesting that the mesopelagic habitat is a major entry point for mercury into marine food webs. These data suggest that a major determinant of mercury levels in oceanic predators is their depth of forage. PMID:19666614

Choy, C Anela; Popp, Brian N; Kaneko, J John; Drazen, Jeffrey C

2009-08-18

117

Impact of forested fallows on fertility and mercury content in soils of the Tapajós River region, Brazilian Amazon.  

PubMed

Recent research on slash-and-burn agriculture conducted in the Amazonian basin has suggested that soils must be left under forested fallows for at least 10 to 15 years to regain fertility levels comparable to non-disturbed forests in order to allow for short cycle crop cultivation. However, small scale farmers tend nowadays to re-burn secondary forests as soon as after 3 to 5 years, thus could contribute to further reduce soil fertility and could enhance the transfer of mercury (Hg) naturally present in soils of the region towards water courses. The present research project sets out to characterize the impact of forested fallows of differing age and land-use history on soils properties (fertility and Hg contents) in the region of the Tapajós River, an active pioneer front of the Brazilian Amazon. To do this, soil samples in forested fallows of variable age and in control primary forests were retrieved. In general, soil fertility of grouped forested fallows of different ages was similar to that of the primary forests. But when discriminating soils according to their texture, forested fallows on coarse grained soils still had much higher NH4/NO3 ratios, NH4 and Ca contents than primary forests, this even 15 years after burning. The impact of repeated burnings was also assessed. Fallows on coarse grained soils showed an impoverishment for all variables related to fertility when the number of burnings was 5 or more. For fallows on fine grained soils that underwent 5 or more burnings, NO3 contents were low although a cation enrichment was observed. Total soil Hg content was also sensitive to repeated burnings, showing similar losses for forested fallows established on both types of soil. However, Hg linked to coarse particles appeared to migrate back towards fine particles at the surface of coarse grained soils in fallows older than 7 years. PMID:23651778

Patry, Cynthia; Davidson, Robert; Lucotte, Marc; Béliveau, Annie

2013-08-01

118

Mercury levels and potential risk from subsistence foods from the Aleutians  

Microsoft Academic Search

Considerable attention has been devoted to contaminants (mainly PCBs and mercury) in subsistence foods (particularly fish) from various parts of the world. However, relatively little attention has been devoted to examining mercury levels in a full range of subsistence foods from a particular region. While managers and scientists compute risk based on site-specific data on contaminant levels and consumption rates,

Joanna Burger; Michael Gochfeld; Christian Jeitner; Sean Burke; Tim Stamm; Ronald Snigaroff; Dan Snigaroff; Robert Patrick; Jim Weston

2007-01-01

119

A Prospective Clinical Study on Blood Mercury Levels Following Endodontic Root-end Surgery with Amalgam  

PubMed Central

Introduction The purpose of this clinical study was to compare the blood mercury levels before and after endodontic surgery using amalgam as a root-end filling material. Materials and Methods Fourteen patients requiring periradicular surgery participated in this prospective clinical study. A zinc-free amalgam was employed as root-end filling material. Blood samples were collected at three intervals: immediately before, immediately after and one week postoperatively. Mercury content of the blood was determined using gold amalgamation cold-vapor atomic absorption spectrometry. Obtained data were analyzed using analysis of variance for repeated measures and paired t-test. Results The mean (SD) of blood mercury levels was 2.20 (0.24) ng/mL immediately before surgery, 2.24 (0.28) ng/mL immediately after surgery and 2.44 (0.17) ng/mL one week after the periradicular surgery. The blood mercury level one week post-operative was significantly higher than both blood mercury levels immediately before (P<0.001) and immediately after (P=0.005) the surgery. Conclusion Placement of an amalgam retroseal during endodontic surgery can increase blood mercury levels after one week. The mercury levels however, are still lower than the toxic mercury levels. We suggest using more suitable and biocompatible root-end filling materials. PMID:23922566

Saatchi, Masoud; Shadmehr, Elham; Talebi, Seyed Morteza; Nazeri, Mohsen

2013-01-01

120

Mercury  

MedlinePLUS

... enters the air from mining ore deposits, burning coal and waste, and from manufacturing plants. It enters ... to cause cancer? There are inadequate human cancer data available for all forms of mercury. Mercuric chloride ...

121

SEVERAL MECHANISMS OF MERCURY RESISTANCE FOUND IN SOIL ISOLATES FROM PAVLODAR, KAZAKHSTAN  

EPA Science Inventory

Abdrashitova, Svetlava A., M.A. Ilyushchenko, A. Yu Kalmykv, S.A. Aitkeldieva, Wendy J. Davis-Hoover and Richard Devereux. In press. Several Mechanisms of Mercury Resistance Found in Soil Isolates from Pavlodar, Kazakhstan (Abstract). To be presented at the Battelle Conference on...

122

Latent Effect of Soil Organic Matter Oxidation on Mercury Cycling within a Southern Boreal Ecosystem  

EPA Science Inventory

The focus of this study is to investigate processes causing the observed spatial variation of total mercury (THg) in the soil O horizon of watersheds within the Superior National Forest (Minnesota) and to determine if results have implications toward understanding long-term chang...

123

Vertical profile measurements of soil air suggest immobilization of gaseous elemental mercury in mineral soil.  

PubMed

Evasion of gaseous elemental Hg (Hg(0)g) from soil surfaces is an important source of atmospheric Hg, but the volatility and solid-gas phase partitioning of Hg(0) within soils is poorly understood. We developed a novel system to continuously measure Hg(0)g concentrations in soil pores at multiple depths and locations, and present a total of 297 days of measurements spanning 14 months in two forests in the Sierra Nevada mountains, California, U.S. Temporal patterns showed consistent pore Hg(0)g concentrations below levels measured in the atmosphere (termed Hg(0)g immobilization), ranging from 66 to 94% below atmospheric concentrations throughout multiple seasons. The lowest pore Hg(0)g concentrations were observed in the deepest soil layers (40 cm), but significant immobilization was already present in the top 7 cm. In the absence of sinks or sources, pore Hg(0)g levels would be in equilibrium with atmospheric concentrations due to the porous nature of the soil matrix and gas diffusion. Therefore, we explain decreases in pore Hg(0)g in mineral soils below atmospheric concentrations--or below levels found in upper soils as observed in previous studies--with the presence of an Hg(0)g sink in mineral soils possibly related to Hg(0)g oxidation or other processes such as sorption or dissolution in soil water. Surface chamber measurements showing daytime Hg(0)g emissions and nighttime Hg(0)g deposition indicate that near-surface layers likely dominate net atmospheric Hg(0)g exchange resulting in typical diurnal cycles due to photochemcial reduction at the surface and possibly Hg(0)g evasion from litter layers. In contrast, mineral soils seem to be decoupled from this surface exchange, showing consistent Hg(0)g uptake and downward redistribution--although our calculations indicate these fluxes to be minor compared to other mass fluxes. A major implication is that once Hg is incorporated into mineral soils, it may be unlikely subjected to renewed Hg(0)g re-emission from undisturbed, background soils emphasizing the important role of soils in sequestering past and current Hg pollution loads. PMID:24428735

Obrist, Daniel; Pokharel, Ashok K; Moore, Christopher

2014-02-18

124

Spatial and vertical distribution of mercury in upland forest soils across the northeastern United States  

PubMed Central

Assessing current Hg pools in forest soils of the northeastern U.S. is important for monitoring changes in Hg cycling. The forest floor, upper and lower mineral horizons were sampled at 17 long-term upland forest sites across the northeastern U.S. in 2011. Forest floor Hg concentration was similar across the study region (274 ± 13 ?g kg?1) while Hg amount at northern sites (39 ± 6 g ha?1) was significantly greater than at western sites (11 ± 4 g ha?1). Forest floor Hg was correlated with soil organic matter, soil pH, latitude and mean annual precipitation and these variables explained approximately 70% of the variability when multiple regressed. Mercury concentration and amount in the lower mineral soil was correlated with Fe, soil organic matter and latitude, corresponding with Bs horizons of Spodosols (Podzols). Our analysis shows the importance of regional and soil properties on Hg accumulation in forest soils. PMID:23911621

Richardson, Justin B.; Friedland, Andrew J; Engerbretson, Teresa R.; Kaste, James M.; Jackson, Brian P.

2013-01-01

125

Application of controlled mesocosms for understanding mercury air-soil-plant exchange.  

PubMed

Whole system elemental mercury (Hg0) flux was measured for approximately 1.5 years using two large gas exchange mesocosms containing approximately 100 two-year old aspen trees (Populus tremuloides) planted in soil with elevated mercury concentrations (12.3 microg/g). We hypothesized that during leafout, whole mesocosm Hg0 flux would increase due to movement of Hg0 in the transpiration stream from the soil to the air. This hypothesis was not supported; plants were found to assimilate Hg0 from the contaminated air, and whole system Hg0 emissions were reduced as plants leafed-out due to shading of the soil. Surface disturbance, watering, and increases in soil moisture, light, and temperature were all found to increase whole system Hg0 flux, with light being a more significant factor. Although surface soils were maintained at 15-20% moisture, daily watering caused pulses of Hg0 to be released from the soil throughout the experiment. Data developed in this experiment suggested that those processes acting on the soil surface are the primary influence on Hg emissions and that the presence of vegetation, which shields soil surfaces from incident light, reduces Hg emissions from enriched soils. PMID:15573605

Gustin, M S; Ericksen, J A; Schorran, D E; Johnson, D W; Lindberg, S E; Coleman, J S

2004-11-15

126

Chapter A5. Section 6.4.B. Low-Level Mercury  

USGS Publications Warehouse

Collecting and processing water samples for analysis of mercury at a low (subnanogram per liter) level requires use of ultratrace-level techniques for equipment cleaning, sample collection, and sample processing. Established techniques and associated quality-assurance (QA) procedures for the collection and processing of water samples for trace-element analysis at the part-per-billion level (NFM 3-5) are not adequate for low-level mercury samples. Modifications to the part-per-billion procedures are necessary to minimize contamination of samples at a typical ambient mercury concentration, which commonly is at the subnanogram-per-liter level.

Lewis, Michael Edward; Brigham, Mark E.

2004-01-01

127

Glutathione enzyme and selenoprotein polymorphisms associate with mercury biomarker levels in Michigan dental professionals  

SciTech Connect

Mercury is a potent toxicant of concern to both the general public and occupationally exposed workers (e.g., dentists). Recent studies suggest that several genes mediating the toxicokinetics of mercury are polymorphic in humans and may influence inter-individual variability in mercury accumulation. This work hypothesizes that polymorphisms in key glutathione synthesizing enzyme, glutathione s-transferase, and selenoprotein genes underlie inter-individual differences in mercury body burden as assessed by analytical mercury measurement in urine and hair, biomarkers of elemental mercury and methylmercury, respectively. Urine and hair samples were collected from a population of dental professionals (n = 515), and total mercury content was measured. Average urine (1.06 {+-} 1.24 ug/L) and hair mercury levels (0.49 {+-} 0.63 ug/g) were similar to national U.S. population averages. Taqman assays were used to genotype DNA from buccal swab samples at 15 polymorphic sites in genes implicated in mercury metabolism. Linear regression modeling assessed the ability of polymorphisms to modify the relationship between mercury biomarker levels and exposure sources (e.g., amalgams, fish consumption). Five polymorphisms were significantly associated with urine mercury levels (GSTT1 deletion), hair mercury levels (GSTP1-105, GSTP1-114, GSS 5 Prime ), or both (SEPP1 3 Prime UTR). Overall, this study suggests that polymorphisms in selenoproteins and glutathione-related genes may influence elimination of mercury in the urine and hair or mercury retention following exposures to elemental mercury (via dental amalgams) and methylmercury (via fish consumption). -- Highlights: Black-Right-Pointing-Pointer We explore the influence of 15 polymorphisms on urine and hair Hg levels. Black-Right-Pointing-Pointer Urine and hair Hg levels in dental professionals were similar to the US population. Black-Right-Pointing-Pointer GSTT1 and SEPP1 polymorphisms associated with urine Hg levels. Black-Right-Pointing-Pointer Accumulation of Hg in hair following exposure from fish was modified by genotype. Black-Right-Pointing-Pointer GSTP1, GSS, and SEPP1 polymorphisms influenced Hg accumulation in hair.

Goodrich, Jaclyn M.; Wang, Yi [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)] [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Gillespie, Brenda [Department of Biostatistics, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)] [Department of Biostatistics, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Werner, Robert [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States) [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Department of Physical Medicine and Rehabilitation, University of Michigan, 325 E. Eisenhower Parkway Suite 100, Ann Arbor, MI 48108 (United States); Franzblau, Alfred [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)] [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Basu, Niladri, E-mail: niladri@umich.edu [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)] [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)

2011-12-15

128

Human hair mercury levels in the Wanshan mercury mining area, Guizhou Province, China  

Microsoft Academic Search

The total mercury (T-Hg) and methyl mercury (Me-Hg) concentrations in the hair were measured to evaluate mercury (Hg) exposure\\u000a for the residents in Da-shui-xi Village (DSX) and Xia-chang-xi Village (XCX) in the Wanshan Hg mining area, Guizhou Province,\\u000a Southwestern China. The mean concentrations in the hair of DSX residents were 5.5 ± 2.7 ?g\\/g and 1.9 ± 0.9 ?g\\/g for T-Hg and\\u000a Me-Hg, respectively. The concentrations

Ping Li; Xinbin Feng; Guangle Qiu; Lihai Shang; Guanghui Li

2009-01-01

129

Complexation of mercury(II) ions with humic acids in tundra soils  

NASA Astrophysics Data System (ADS)

The interaction mechanisms of mercury(II) ions with preparations of humic acids (HAs) isolated from organic horizons of surface-gleyed soils (Haplic Stagnosol (Gelic, Siltic)) of shrub tundra and hydromorphic peat gley soils (Histic Cryosol (Reductaquic, Siltic)) of moss-lichen tundra have been studied. The particular features of the interactions between the mercury(II) ions and the HAs are related to the molecular structure of the HAs, the mercury concentration range, and the environmental parameters. The fixation of mercury(II) ions into stable coordination compounds is most efficient in the pH range of 2.5-3.5. At the element concentrations below 0.50 ?mol/dm3, the main complexing sites of HAs are their peripheral aminoacid functional groups. Pyrocatechol, salicylate, and phenolic groups from the nuclear moiety of molecules interact in the concentration range of 0.0005-0.50 mmol/dm3; the physical sorption of mercury hydroxo complexes by the surface of HAs is the main process occurring in the system.

Vasilevich, R. S.; Beznosikov, V. A.; Lodygin, E. D.; Kondratenok, B. M.

2014-03-01

130

Efficiency of white lupin in the removal of mercury from contaminated soils: soil and hydroponic experiments.  

PubMed

This study examined the ability of the white lupin to remove mercury (Hg) from a hydroponic system (Hg concentrations 0, 1.25, 2.5, 5 and 10 micromol/L) and from soil in pots and lysimeters (total Hg concentration (19.2 +/- 1.9) mg/kg availability 0.07%, and (28.9 +/- 0.4) mg/kg availability 0.09%, respectively), and investigated the accumulation and distribution of Hg in different parts of the plant. White lupin roots efficiently took up Hg, but its translocation to the harvestable parts of the plant was low. The Hg concentration in the seeds posed no risk to human health according to the recommendations of the World Health Organization, but the shoots should not be used as fodder for livestock, at least when unmixed with other fodder crops. The accumulation of Hg in the hydroponically-grown plants was linear over the concentration range tested. The amount of Hg retained in the roots, relative to the shoots, was almost constant irrespective of Hg dose (90%). In the soil experiments, Hg accumulation increased with exposure time and was the greater in the lysimeter than in the pot experiments. Although Hg removal was the greater in the hydroponic system, revealing the potential of the white lupin to extract Hg, bioaccumulation was the greatest in the lysimeter-grown plants; the latter system more likely reflects the true behaviour of white lupin in the field when Hg availability is a factor that limits Hg removal. The present results suggest that the white lupin could be used in long-term soil reclamation strategies that include the goal of profitable land use in Hg-polluted areas. PMID:20614785

Zornoza, Pilar; Millán, Rocío; Sierra, M José; Seco, Almudena; Esteban, Elvira

2010-01-01

131

Mercury Release from Soils and Sediments in the Sacramento River Watershed  

NASA Astrophysics Data System (ADS)

Mercury released into water from soils and sediments contaminated by cinnabar (HgS) and gold mining is a major environmental concern in the Sacramento-San Joaquin Delta, California. To better understand the conditions resulting in Hg solubilization from these contaminated materials, six soil and sediment samples from the Coastal Range and the Sierra Nevada were subject to batch leaching experiments under varying conditions. Sequential extraction analyses of the soils and sediments indicated that most of the mercury was present as (1) Hg as HgS in samples affected by HgS mining, which occurred in the Coastal Range, (2) Hg bound to metal oxides in a background serpentine soil from the Coastal Range, (3) Hg bound to sediment organic matter in lake sediments from Camp Far West Reservoir, and (4) elemental Hg in a sluice sediment from Starr Tunnel. The effects of pH, ionic strength, inorganic ions (chloride, calcium), simple organic ligands (mercaptoacetic acid, salicylic acid, EDTA), and dissolved organic matter (DOM) on the release of Hg were investigated. Leaching experiments confirmed that the water-soluble fraction was small (9 to 350 ng/L) compared to the amounts of Hg associated with the solid samples (1 to 36 ?g/g total mercury); however, these concentrations would be sufficient to result in increased methylation by sulfate-reducing bacteria in wetland systems. An increase in mercury release was observed with (1) increasing pH due to solubilization of soil organic matter, (2) decreasing ionic strength due to colloid stabilization, and (3) increasing chloride concentration due to the formation of complexes with mercury. The presence of calcium strongly inhibited mercury release. Among the organic ligands, mercaptoacetic acid, which binds Hg very strongly, was the most effective at solubilizing Hg. DOM, in the form of organic matter isolates, was also very effective at solubilizing Hg for all samples except the lake sediment sample, with the most aromatic organic matter isolates being the most reactive. The results of this study indicate that DOM is very important in the mobilization of Hg from soils and sediments and will influence the dissolution, mobilization, and bioavailability of mercury in wetlands associated with the Sacramento-San Joaquin Delta area.

Suess, E.; Aiken, G. R.; Ryan, J. N.; Gasper, J. D.

2007-12-01

132

A simple spectrophotometric determination of trace level mercury using 1,5-diphenylthiocarbazone solubilized in micelle.  

PubMed

A very simple, ultra-sensitive and fairly selective non-extractive spectrophotmetric method is presented for the rapid determination of mercury(II) at ultra-trace level using 1,5-diphenylthiocarbazone (dithizone) as a new micellar spectrophotometric reagent (lambdamax = 490 nm) in a slightly acidic (0.07 - 0.17 M H2SO4) aqueous solution. The presence of a micellar system avoids the previous steps of solvent extraction and reduces the cost, toxicity while enhancing the sensitivity, selectivity and the molar absorptivity. The reaction is instantaneous and the absorbance remains stable for over 24 h. The average molar absorption coefficient and Sandell's sensitivity were found to be 5.02 x 10(4) L mol(-1) cm(-1) and 10 ng cm(-2) of Hg, respectively. Linear calibration graphs were obtained for 0.05 - 10 mg L(-1) of Hg; the stoichiometric composition of the chelate is 1:2 (Hg:dithizone). The method is characterized by a detection limit of 1 microg L(-1) of Hg. Large excesses of over 60 cations, anions and complexing agents (e.g. EDTA, tartrate, oxalate, citrate, phosphate, thiourea, azide, SCN-) do not interfere in the determination. The method was successfully applied to a number of environmental water samples (potable and polluted), biological samples (human blood and urine; milk and fish) and soils; solutions contained both mercury(I) and mercury(II) as well as complex synthetic mixtures. The method has high precision and accuracy (s = +/-0.01 for 0.1 mg L(-1)). PMID:15913137

Khan, Humaira; Ahmed, M Jamaluddin; Bhanger, M Iqbal

2005-05-01

133

Comparative Analysis for Polluted Agricultural Soils with Arsenic, Lead, and Mercury in Mexico  

SciTech Connect

The use of mercury in Mexico has been associated with the mining industry of Zacatecas. This activity has polluted several areas currently used for agriculture. The main objective of this study was to investigate the heavy metal concentration (Hg, As and Pb) in soil of Guadalupe Zacatecas in order to justify a further environmental risk assessment in the site. A 2X3 km grid was used for the sampling process and 20 soil samples were taken. The analysis was developed using EPA SW 846: 3050B/6010B method for arsenic and metals and EPA SW 846: 7471A for total mercury. It was concluded that there are heavy metals in agricultural soils used for corn and bean farming. For this it is required to make an environmental risk assessment and a bioavailability study in order to determine if there's a risk for heavy metals bioaccumulation in animals or human beings or metal lixiviation to aquifers.

Yarto-Ramirez, Mario; Santos-Santos, Elvira; Gavilan-Garcia, Arturo; Castro-Diaz, Jose; Gavilan-Garcia, Irma Cruz; Rosiles, Rene; Suarez, Sara

2004-03-31

134

Field analytical techniques for mercury in soils technology evaluation. Topical report, November 1994--March 1997  

SciTech Connect

This report presents the evaluation of the four field analytical techniques for mercury detection in soils, namely (1) an anodic stripping voltametry technique (ASV) developed and tested by General Electric Corporation; (2) a static headspace analysis (SHSA) technique developed and tested by Dr. Ralph Turner of Oak Ridge National Laboratory; (3) the BiMelyze{reg_sign} Mercury Immunoassay (Bio) developed and tested by BioNebraska, Inc.; and (4) a transportable x-ray fluorescence (XRF) instrument/technique developed and tested by Spectrace, Inc.

Solc, J.; Harju, J.A.; Grisanti, A.A.

1998-02-01

135

Mercury Levels in Locally Manufactured Mexican Skin-Lightening Creams  

PubMed Central

Mercury is considered one of the most toxic elements for plants and animals. Nevertheless, in the Middle East, Asia and Latin America, whitening creams containing mercury are being manufactured and purchased, despite their obvious health risks. Due to the mass distribution of these products, this can be considered a global public health issue. In Mexico, these products are widely available in pharmacies, beauty aid and health stores. They are used for their skin lightening effects. The aim of this work was to analyze the mercury content in some cosmetic whitening creams using the cold vapor technique coupled with atomic absorption spectrometry (CV-AAS). A total of 16 skin-lightening creams from the local market were investigated. No warning information was noted on the packaging. In 10 of the samples, no mercury was detected. The mercury content in six of the samples varied between 878 and 36,000 ppm, despite the fact that the U.S. Food and Drug Administration (FDA) has determined that the limit for mercury in creams should be less than 1 ppm. Skin creams containing mercury are still available and commonly used in Mexico and many developing countries, and their contents are poorly controlled. PMID:21776243

Peregrino, Claudia P.; Moreno, Myriam V.; Miranda, Silvia V.; Rubio, Alma D.; Leal, Luz O.

2011-01-01

136

Mercury levels in Great Lakes herring gull eggs, 1972--1992  

SciTech Connect

Since 1971, the herring gull (Larus argentatus) has been used as a sentinel species for monitoring the levels of persistent contaminants in the Great Lakes ecosystem. In this study, 21 herring gull colonies in the Great Lakes and connecting channels were sampled for years 1972--1976, 1981--1983, 1985 and 1992. For each year, 10 eggs (usually) were collected from each colony site and analyzed for total mercury (ppm, wet weight). Results indicated that eggs from Lake Ontario displayed the highest mercury levels, mean = 0.28 (s.d. = 0.08) to 0.73 (0.23). Lake Erie typically displayed the lowest egg mercury levels, 0.18 (0.08) to 0.24 (0.11). Overall, mercury levels ranged from 0.12 (0.02) in 1985 to 0.88 (0.23) in 1982 for Channel-Shelter Island (Lake Huron) and Pigeon Island (Lake Ontario), respectively. Generally, all colony sites showed peak mercury levels in 1982. A significant decline in egg mercury levels was observed in six colony sites between 1972 and 1992 and in three colony sites between 1981 and 1992. The mean herring gull egg mercury levels observed in the early and mid 1970s and in 1982 for some colony sites were within the range found which potentially reduces hatchability in other fish-eating bird species.

Weseloh, D.V.; Koster, M.D.; Ryckman, D.P.; Struger, J. [Canadian Wildlife Service, Burlington, Ontario (Canada). Canada Centre for Inland Waters

1995-12-31

137

Dry deposition of gaseous elemental mercury to plants and soils using mercury stable isotopes in a controlled environment  

NASA Astrophysics Data System (ADS)

Uptake of gaseous elemental mercury (Hg 0(g)) by three plant species and two soil types was measured using mercury vapor enriched in the 198 isotope ( 198Hg 0(g)). The plant species and soil types were: White Ash ( Fraxinus Americana; WA); White Spruce ( Picea Glauca; WS); Kentucky Bluegrass ( Poa Partensis; KYBG); Plano Silt Loam (4% organic matter; PSL); and Plainfield Sand/Sparta Loamy Sand (1.25-1.5% organic matter: PS). The plants and soils were exposed to isotopically enriched Hg 0(g) in a 19 m 3 controlled environment room for 7 days under optimal plant growth conditions (20 °C, 140 Wm -2 between 300 nm and 700 nm; 70% RH) and atmospherically relevant Hg 0(g) concentrations. Mercury was recovered from the samples using acidic digestions and surface leaches, and then analyzed for enrichments in 198Hg by ICPMS. The method was sensitivity enough that statistically significant enrichments in 198Hg were measured in the plant foliage at the end of Day 1. Whole leaf digestions and surface-selective leaches revealed that accumulative uptake was predominantly to the interior of the leaf under the conditions studied. Uptake fluxes for WA increased between the first and third days and remained constant thereafter (WA; Day 1 = 7 ± 2 × 10 -5 ng m -2 s -1; Days 3-7 = 1.3 ± 0.1 × 10 -4 ng m -2 s -1; where m 2 refers to one sided leaf area). KYBG demonstrated similar behavior although no Day 3 measurement was available (Day 1 = 7.5 ± 0.5 × 10 -5 ng m -2 s -1; Day 7 = 1.2 ± 0.1 × 10 -4 ng m -2 s -1). Fluxes to White Spruce were lower, with little difference between Days 1 and 3 followed by a decrease at Day 7 (WS; Days 1-3 = 5 ± 2 × 10 -5 ng m -2 s -1; Day 7 = 2.4 ± 0.2 × 10 -5 ng m -2 s -1). Uptake of Hg to soils was below the method detection limit for those media (PSL = 3 × 10 -2 ng m -2 s -1; PS = 3 × 10 -3 ng m -2 s -1) over the 7 day study period. Foliar resistances calculated for each species compared well to previous studies.

Rutter, Andrew P.; Schauer, James J.; Shafer, Martin M.; Creswell, Joel E.; Olson, Michael R.; Robinson, Michael; Collins, Ryan M.; Parman, Andrew M.; Katzman, Tanya L.; Mallek, Justin L.

2011-02-01

138

Behavior of Mercury in Soil Profiles: Impact of Increased Precipitation, Acidity, and Fertilization on Mercury Methylation  

Microsoft Academic Search

The behaviour of Hg in mineral pine forest (Pinussylvestris soil profiles (0–16 cm) was studied usinga lysimeter experimental design combined with thelabeling technique with 203HgCl2. Thelabeled surface soils were exposed to four differenttreatments: (i) normal precipitation (600 mma-1), (ii) four-fold precipitation, (iii) soilP-K fertilizing with normal precipitation, and (iv) the increased acidity in the rainwater with normalamount of precipitation. After

T. Matilainen; M. Verta; H. Korhonen; A. Uusi-Rauva; M. Niemi

2001-01-01

139

Latent effect of soil organic matter oxidation on mercury cycling within a southern boreal ecosystem.  

PubMed

The focus of this study is to investigate processes causing the observed spatial variation of total mercury (THg) in the soil O horizon of watersheds within the Superior National Forest (Minnesota) and to determine if results have implications toward understanding long-term changes in THg concentrations for resident fish. Principal component analysis was used to evaluate the spatial relationships of 42 chemical elements in three soil horizons over 10 watersheds. Results indicate that soil organic carbon is the primary factor controlling the spatial variation of certain metals (Hg, Tl, Pb, Bi, Cd, Sn, Sb, Cu, and As) in the O and A soil horizons. In the B/E horizon, organic carbon appeared to play a minor role in metal spatial variation. These characteristics are consistent with the concentration of soil organic matter and carbon decreasing from the O to the B/E horizons. We also investigated the relationship between percent change in upland soil organic content and fish THg concentrations across all watersheds. Statistical regression analysis indicates that a 50% reduction in age-one and age-two fish THg concentration could result from an average 10% decrease in upland soil organic content. Disturbances that decrease the content of THg and organic matter in the O and A horizons (e.g., fire) may cause a short-term increase in atmospherically deposited mercury but, over the long term, may lead to decreased fish THg concentrations in affected watersheds. PMID:22370412

Gabriel, Mark; Kolka, Randy; Wickman, Trent; Woodruff, Laurel; Nater, Ed

2012-01-01

140

Mercury  

NSDL National Science Digital Library

This NASA (National Aeronautics and Space Administration) planet profile provides data and images of the planet Mercury. These data include planet size, distance from the Sun, rotation and revolution times, temperature, atmospheric composition, density, and albedo. Images of the planet include general surface features such as crater basins, the Caloris Basin, and other images taken by the Mariner 10 spacecraft.

141

Mercury  

Microsoft Academic Search

Mercury is the least-explored planet except for Pluto. The Mariner 10 mission yielded much information about the planet, but raised new questions. Groundbased observations of the polar craters and atmosphere have also raised new questions. The Messenger mission will address many of these, but in order to maximize the return from this mission, a program of laboratory, observational, and theoretic

A. E. Potter; R. M. Killen; B. Hapke

2002-01-01

142

Mercury levels in a 21-year-old black-crowned night heron (Nycticorax nycticorax)  

Microsoft Academic Search

Mercury levels in a 21-year-old black crowned night heron were measured. Concentrations were: breast muscle (0.9 ppm), liver (3.1 ppm), brain (0.5ppm), and primary wing feathers (17.9 ppm). These levels were not substantially different from those found in much younger birds. These data imply that either the kind had been feeding in an area with low levels of mercury contaminations

Hoffman

1976-01-01

143

Gaseous mercury emissions from soil following forest loss and land use changes: Field experiments in the United States and Brazil  

NASA Astrophysics Data System (ADS)

Forest ecosystems are a sink of atmospheric mercury, trapping the metal in the canopy, and storing it in the forest floor after litter fall. Fire liberates a portion of this mercury; however, little is known about the long-term release of mercury post deforestation. We conducted two large-scale experiments to study this phenomenon. In upstate New York, gaseous mercury emissions from soil were monitored continually using a Teflon dynamic surface flux chamber for two-weeks before and after cutting of the canopy on the edge of a deciduous forest. In Brazil, gaseous mercury emissions from soil were monitored in an intact Ombrophilous Open forest and an adjacent field site both before and after the field site was cleared by burning. In the intact forest, gaseous mercury emissions from soil averaged -0.73 ± 1.84 ng m-2 h-1 (24-h monitoring) at the New York site, and 0.33 ± 0.09 ng m-2 h-1 (daytime-only) at the Brazil site. After deforestation, gaseous mercury emissions from soil averaged 9.13 ± 2.08 ng m-2 h-1 in New York and 21.2 ± 0.35 ng m-2 h-1 at the Brazil site prior to burning. Gaseous mercury emissions averaged 74.9 ± 0.73 ng m-2 h-1 after burning of the cut forest in Brazil. Extrapolating our data, measured over several weeks to months, to a full year period, deforested soil is estimated to release an additional 2.30 g ha-1 yr-1 of gaseous mercury to the atmosphere in the Brazilian experiment and 0.41 g ha-1 yr-1 in the New York experiment. In Brazil, this represents an additional 50% of the mercury load released during the fire itself.

Carpi, Anthony; Fostier, Anne H.; Orta, Olivia R.; dos Santos, Jose Carlos; Gittings, Michael

2014-10-01

144

MERCURY LEVELS IN HAWAIIAN PREDATORY PEI-AGIC FISHES AND THEIR PREY ASA FUNCTION OF DEPTH AND ECOLOGY  

E-print Network

MERCURY LEVELS IN HAWAIIAN PREDATORY PEI-AGIC FISHES AND THEIR PREY ASA FUNCTION OF DEPTH Gregory F,. P.av:.zza N{argaretA. N.,Icl\\{anus #12;ABSTRACT Mercury is drstributedthroughout the Earth in plants and animals. Inter- and intra-specific variations in mercury levels of predatory pelagic fish have

Luther, Douglas S.

145

Health effects in the Flemish population in relation to low levels of mercury exposure: from organ to transcriptome level.  

PubMed

Due to possible health risks, quantification of mercury accumulation in humans was included in the Flemish biomonitoring programmes FLEHS I (2002-2006) and FLEHS II (2007-2011). The general objective of FLEHS I was to assess regional exposure levels in order to link possible differences in these internal exposure levels to different types of local environmental pressure. Therefore, Hg and MMHg (methylmercury) were only measured in pooled blood samples per region and per age class. In FLEHS II, mercury concentrations were measured in hair of each participant. About 200 adolescents and 250 mothers (reference group) and two times 200 adolescents (2 hotspots) were screened. The main objectives of the FLEHS II study were: (1) to determine reference levels of mercury in hair for Flanders; (2) to assess relations between mercury exposure and possible sources like fish consumption; (3) to assess dose-effect relations between mercury exposure and health effect markers. The results showed that mercury concentrations in the Flemish population were rather low compared to other studies. Mercury levels in the Flemish populations were strongly related to the age of the participants and consumption of fish. Significant negative associations were observed between mercury in hair and asthma, having received breast feeding as a newborn, age at menarche in girls, allergy for animals and free testosterone levels. Significant correlations were also observed between mercury in hair and genes JAK2, ARID4A, Hist1HA4L (boys) and HLAdrb5, PIAS2, MANN1B1, GIT and ABCA1 (girls). PMID:23920476

Croes, Kim; De Coster, Sam; De Galan, Sandra; Morrens, Bert; Loots, Ilse; Van de Mieroop, Els; Nelen, Vera; Sioen, Isabelle; Bruckers, Liesbeth; Nawrot, Tim; Colles, Ann; Den Hond, Elly; Schoeters, Greet; van Larebeke, Nicolas; Baeyens, Willy; Gao, Yue

2014-03-01

146

Cytogenetic damage related to low levels of methyl mercury contamination in the Brazilian Amazon  

E-print Network

, Mitotic Index, Cytogenetics. INTRODUCTION Since the late seventies extensive gold mining op- erations, from mining operations and lixiviation of soils after deforesta- tion, is considered to be the main clinical signs and symptoms of mercury poisoning occur. The first apparent biological effect

Long, Bernard

147

Spatial and Temporal Evolution of Mercury in Post-fire Soils in Southern California Watersheds  

NASA Astrophysics Data System (ADS)

Wildfires are well known sources of mercury (Hg) to the atmosphere, but there is a paucity of data characterizing how fire impacts the transport of Hg to surface waters where methylation can occur. Because post-fire storm events have the potential to carry large sediment loads to a stream system, it is important to understand the effects of wildfire on Hg binding and relative variability in terrestrial soils in order to assess its transport potential in burned watersheds. It has been widely reported that Hg stored in surface soils is lost to the atmosphere due to volatilization during wildfire and that higher metal concentrations are associated with fine-grained particle fractions due to higher surface area/volume ratios, and consequently, available binding sites. Following southern California's September 2006 Day Fire, seasonal terrestrial sampling was undertaken at burned and unburned soils over a 1.5 year period to assess both immediate and long term impacts of the fire on Hg binding in the soils of Piru Creek watershed. Freshly burned soils exhibited the loss of Hg at the surface that would be expected due to volatilization during the fire, but this was followed by a sharp increase in [Hg] in surface soils over the subsequent recovery period that was not seen in the unburned soils. Soils were also size-fractionated and Hg was measured on each grain size. Mercury in the fine grained soil fraction (<250 um) was not significantly higher than that measured in the coarser grain size fractions. This is contrary to the behavior observed in the unburned soils and has implications for modeling Hg transport to surface waters as a function of hill slope erosional processes and sediment re- distribution in burned watersheds.

Burke, M. P.; Ferreira, M.; Mendez, C. B.; Navarro, B. I.; Jay, J. A.; Hogue, T. S.

2008-12-01

148

Bench- and pilot-scale demonstration of thermal desorption for removal of mercury from the Lower East Fork Poplar Creek floodplain soils  

SciTech Connect

Thermal desorption is an innovative technology that has seen significant growth in applications to organically contaminated soils and sludges for the remediation of hazardous, radioactive and mixed waste sites. This paper will present the results of a bench and pilot-scale demonstration of this technology for the removal of mercury from the Lower East Fork Poplar Creek floodplain soil. Results demonstrate that the mercury in this soil can be successfully removed to the target treatment levels of 10 milligrams per kilogram (mg/kg) and that all process residuals could be rendered RCRA-nonhazardous as defined by the Resource Conservation and Recovery Act. Sampling and analyses of the desorber off-gas before and after the air pollution control system demonstrated effective collection of mercury and organic constituents. Pilot-scale testing was also conducted to verify requirements for material handling of soil into and out of the process. This paper will also present a conceptual design and preliminary costs of a full-scale system, including feed preparation, thermal treatment, and residuals handling for the soil.

Morris, M.I. [Oak Ridge National Lab., TN (United States); Sams, R.J.; Gillis, G. [Oak Ridge Y-12 Plant, TN (United States); Helsel, R.W.; Alperin, E.S.; Geisler, T.J.; Groen, A.; Root, D. [IT Corp., Knoxville, TN (United States)

1995-04-01

149

Elevated mercury levels in a wintering population of common eiders (Somateria mollissima) in the northeastern United States.  

PubMed

In North America and Europe, sea ducks are important indicators of ecological health and inshore marine pollution. To explore spatial variation in mercury accumulation in common eiders in the northeastern United States, we compared concentrations of total mercury in common eider blood at several New England locations between 1998 and 2013. Eider food items (mollusks) were collected and analyzed to determine if mercury concentrations in eider blood were indicative of local mercury bioavailability. Eiders from Plum Island Sound, MA had a significantly higher mean blood mercury concentration (0.83 ?g/g) than those in other locations. Mean mercury levels in this population were also nearly three times higher than any blood mercury concentrations reported for common eiders in published literature. We observed consistent patterns in eider blood mercury and blue mussel mercury concentrations between sites, suggesting a tentative predictive quality between the two species. PMID:25066457

Meattey, Dustin E; Savoy, Lucas; Beuth, Josh; Pau, Nancy; O'Brien, Kathleen; Osenkowski, Jason; Regan, Kevin; Lasorsa, Brenda; Johnson, Ian

2014-09-15

150

Temporal characterization of mercury accumulation at different trophic levels and implications for metal biomagnification along a coastal food web.  

PubMed

The main goal of this study was to assess temporal mercury variations along an estuarine food web to evaluate the mercury contamination level of the system and the risks that humans are exposed to, due to mercury biomagnification. The highest mercury concentrations in the sediments and primary producers (macrophytes) were observed during winter sampling. Instead, the highest mercury concentrations in the water, suspended particulate matter as well as in the zooplanktonic and suprabenthic communities were observed during summer sampling. Evidences of mercury biomagnification along the food web were corroborated by the positive biomagnification factors, particularly for omnivorous macrobenthic species. Comparing the mercury levels at distinct components with several environmental quality criteria it suggests that sediments, water and edible species (e.g., bivalve Scrobicularia plana and the crustacean Carcinus maenas) presented higher mercury levels than the values accepted by legislation which represent a matter of concern for the environment and human health. PMID:25172612

Cardoso, P G; Pereira, E; Duarte, A C; Azeiteiro, U M

2014-10-15

151

Importance of Forest Composition on Mercury Deposition through Litterfall and Accumulation in Soils  

NASA Astrophysics Data System (ADS)

Upland forests receive greater atmospheric deposition of mercury (Hg) than non-forested areas. In addition to wet deposition of Hg, forests are subjected to Hg deposition in throughfall and litterfall: dry deposition to leaves may be subsequently leached in throughfall; elemental Hg may enter leaves and be later deposited in the leaf litter (litterfall). This research evaluated the importance of forest type on the Total Hg (THg) flux in litterfall and on THg accumulation in organic soil horizons. Eighteen research sites were sampled throughout Vermont, USA. Mercury concentration was measured in senescing leaves of dominant tree species (16 species in total) in three forest types (low-elevation coniferous, mixed, and deciduous/Northern Hardwood forest). Leaf traps were used to measure the litterfall flux. Upper soil horizons were sampled and analyzed for mercury and carbon. Mercury concentration in senescing leaves varied significantly between tree species. Some hardwood species had higher THg concentration in leaves than coniferous species. Striped maple (Acer pensylvanicum) had significantly higher THg concentration than any other species. Total Hg concentration was negatively correlated with leaf height on the tree. Leaf surface-to-weight ratio was positively correlated with THg. The calculated THg flux in litterfall varied from 12 to 28 ug/m2/yr; there was no significant difference between forest types. Results showed an unexpectedly high THg concentration in understory trees. The assumption that needles have greater THg concentration than leaves needs to be revisited; forest structure needs to be taken into account. Total Hg concentration and THg to carbon ratio were consistent within soil horizons but differed among horizons. Similar to other studies, THg concentration was lower in the Oi horizon (litter layer) and peaked in the Oe horizon (fermentation layer) before declining in the humified Oa and/or A horizons. Mineral soil (A horizons) tended to have greater THg pools due to their greater bulk density compared with organic soil horizons (e.g. Oa). Deciduous sites had on average thinner Oe horizons and shallower mineral A horizons compared to sites with more coniferous species. Because of these two factors, deciduous sites had greater THg pools in the upper soil profile (9 cm) than sites with more coniferous species. These results indicate that factors affecting the depth of organic soil horizons need to be taken into account when comparing THg pools between sites. Soil pools are affected both by the THg concentration and the density of the soil.

Juillerat, J. I.; Ross, D. S.

2010-12-01

152

Mercury  

NASA Technical Reports Server (NTRS)

Prior to the flight of the Mariner 10 spacecraft, Mercury was the least investigated and most poorly known terrestrial planet (Kuiper 1970, Devine 1972). Observational difficulties caused by its proximity to the Sun as viewed from Earth caused the planet to remain a small, vague disk exhibiting little surface contrast or details, an object for which only three major facts were known: 1. its bulk density is similar to that of Venus and Earth, much greater than that of Mars and the Moon; 2. its surface reflects electromagnetic radiation at all wavelengths in the same manner as the Moon (taking into account differences in their solar distances); and 3. its rotation period is in 2/3 resonance with its orbital period. Images obtained during the flyby by Mariner 10 on 29 March 1974 (and the two subsequent flybys on 21 September 1974 and 16 March 1975) revealed Mercury's surface in detail equivalent to that available for the Moon during the early 1960's from Earth-based telescopic views. Additionally, however, information was obtained on the planet's mass and size, atmospheric composition and density, charged-particle environment, and infrared thermal radiation from the surface, and most significantly of all, the existence of a planetary magnetic field that is probably intrinsic to Mercury was established. In the following, this new information is summarized together with results from theoretical studies and ground-based observations. In the quantum jumps of knowledge that have been characteristic of "space-age" exploration, the previously obscure body of Mercury has suddenly come into sharp focus. It is very likely a differentiated body, probably contains a large Earth-like iron-rich core, and displays a surface remarkably similar to that of the Moon, which suggests a similar evolutionary history.

Gault, D. E.; Burns, J. A.; Cassen, P.; Strom, R. G.

1977-01-01

153

Mercury levels and its chemical form in tissues and organs of seabirds  

Microsoft Academic Search

Liver, muscle, kidney, and feather samples from nine species of seabirds were analyzed for total and organic (methyl) mercury (MM). Total mercury (TM) levels in liver showed great intra- and inter-species variations, with the concentrations varied from 306 µg\\/g (dry weight) in black-footed albatross (Diomedea nigripes) to 4.9 µg\\/g in arctic tern (Sterna paradisaea), while MM levels were less relatively

E. Y. Kim; T. Murakami; K. Saeki; R. Tatsukawa

1996-01-01

154

An Exploration of Mercury Soils Treatment Technologies for the Y-12 Plant - 13217  

SciTech Connect

There are a number of areas at the Y-12 National Security Complex (Y-12) that have been contaminated with mercury due to historical mercury use and storage. Remediation of these areas is expected to generate large volumes of waste that are Resource Conservation and Recovery Act (RCRA) characteristically hazardous. These soils will require treatment to meet RCRA Land Disposal Restrictions (LDR) prior to disposal. URS - CH2M Oak Ridge LLC (UCOR) performed a feasibility assessment to evaluate on-site and off-site options for the treatment and disposal of mercury-contaminated soil from the Y-12 Site. The focus of the feasibility assessment was on treatment for disposal at the Environmental Management Waste Management Facility (EMWMF) located on the Oak Ridge Reservation. A two-phase approach was used in the evaluation process of treatment technologies. Phase 1 involved the selection of three vendors to perform treatability studies using their stabilization treatment technology on actual Y-12 soil. Phase II involved a team of waste management specialists performing an in-depth literature review of all available treatment technologies for treating mercury contaminated soil using the following evaluation criteria: effectiveness, feasibility of implementation, and cost. The result of the treatability study and the literature review revealed several viable on-site and off-site treatment options. This paper presents the methodology used by the team in the evaluation of technologies especially as related to EMWMF waste acceptance criteria, the results of the physical treatability studies, and a regulatory analysis for obtaining regulator approval for the treatment/disposal at the EMWMF. (authors)

Wrapp, John [UCOR, P.O. Box 4699, Oak Ridge, TN 37831 (United States)] [UCOR, P.O. Box 4699, Oak Ridge, TN 37831 (United States); Julius, Jonathon [DOE Oak Ridge (United States)] [DOE Oak Ridge (United States); Browning, Debbie [Strata-G, LLC, 2027 Castaic Lane, Knoxville, TN, 37932 (United States)] [Strata-G, LLC, 2027 Castaic Lane, Knoxville, TN, 37932 (United States); Kane, Michael [RSI, P.O. Box 4699, Oak Ridge, TN 37831 (United States)] [RSI, P.O. Box 4699, Oak Ridge, TN 37831 (United States); Whaley, Katherine [RSI, P.O. Box 4699, Oak Ridge, TN 37831 (United States)] [RSI, P.O. Box 4699, Oak Ridge, TN 37831 (United States); Estes, Chuck [EnergySolutions, P.O. Box 4699, Oak Ridge, TN 37831 (United States)] [EnergySolutions, P.O. Box 4699, Oak Ridge, TN 37831 (United States); Witzeman, John [RSI, P.O. Box 4699, Oak Ridge, TN, 37831 (United States)] [RSI, P.O. Box 4699, Oak Ridge, TN, 37831 (United States)

2013-07-01

155

Increased mercury in forest soils under elevated carbon dioxide  

Microsoft Academic Search

Fossil fuel combustion is the primary anthropogenic source of both CO2 and Hg to the atmosphere. On a global scale, most Hg that enters ecosystems is derived from atmospheric Hg that deposits\\u000a onto the land surface. Increasing concentrations of atmospheric CO2 may affect Hg deposition to terrestrial systems and storage in soils through CO2-mediated changes in plant and soil properties.

Susan M. Natali; Sergio A. Sańudo-Wilhelmy; Richard J. Norby; Hong Zhang; Adrien C. Finzi; Manuel T. Lerdau

2008-01-01

156

Electrochemically enhanced oxidation reactions in sandy soil polluted with mercury  

Microsoft Academic Search

For remediation of soils contaminated with heavy metals, the electrodialytic remediation (EDR) method is a highly relevant method, see e.g. Hansen et al. (Hansen HK, Ottosen LM, Kliem BK, Villumsen A. Electrodialytic remediation of soils polluted with Cu, Cr, Hg, Pb, and Zn. J Chem Tech Biotechnol 1997;70:67–73). During the process the heavy metals are transferred to the pore water

Jorg Thöming; Bodil K. Kliem; Lisbeth M. Ottosen

2000-01-01

157

Cinnabar is different from mercuric chloride in mercury absorption and influence on the brain serotonin level.  

PubMed

The toxicity of cinnabar, a naturally occurring mercury sulphide (HgS), has long been referred to soluble mercury chloride (HgCl2 ). To investigate whether the speciation of mercury plays a role in its disposition and toxicity, we hereby investigated and compared cinnabar with soluble HgCl2 and pure insoluble HgS in mice on mercury absorption, tissue distribution and in relation to the biological effects. The male C57BL/6J mice were treated by oral administration of various doses of cinnabar, with 0.01 g/kg of HgCl2 for comparison, or the same dose of cinnabar or pure HgS (0.1 g/kg), once a day for 10 consecutive days. The total mercury contents in serum and tissue (brain, kidney, liver) were measured by atomic fluorescence spectrometer (AFS). The biological effects investigated involved monoamine neurotransmitters (serotonin, 5-HT) in brain as an indicator of therapeutic function, and serum alanine transaminase (ALT) as a marker of hepatic damage, blood urea nitrogen (BUN) and serum creatinine as markers for renal function. The mercury absorption of cinnabar or HgS was much less than that of HgCl2 . The mercury levels in brains of the cinnabar group were only slightly changed and kept in a steady-state with the dose elevated. Cinnabar or HgS suppressed brain 5-HT levels. HgCl2 could not cause any changes in brain 5-HT although the mercury level increased considerably. The results revealed that cinnabar or HgS is markedly different from HgCl2 in mercury absorption, tissue distribution and influence on brain 5-HT levels, which suggests that the pharmacological and/or toxicological effects of cinnabar undertake other pathways from mercuric ions. PMID:23302034

Wang, Qi; Yang, Xiaoda; Zhang, Baoxu; Yang, Xiuwei; Wang, Kui

2013-06-01

158

A reactive transport model for mercury fate in soil-application to different anthropogenic pollution sources.  

PubMed

Soil systems are a common receptor of anthropogenic mercury (Hg) contamination. Soils play an important role in the containment or dispersion of pollution to surface water, groundwater or the atmosphere. A one-dimensional model for simulating Hg fate and transport for variably saturated and transient flow conditions is presented. The model is developed using the HP1 code, which couples HYDRUS-1D for the water flow and solute transport to PHREEQC for geochemical reactions. The main processes included are Hg aqueous speciation and complexation, sorption to soil organic matter, dissolution of cinnabar and liquid Hg, and Hg reduction and volatilization. Processes such as atmospheric wet and dry deposition, vegetation litter fall and uptake are neglected because they are less relevant in the case of high Hg concentrations resulting from anthropogenic activities. A test case is presented, assuming a hypothetical sandy soil profile and a simulation time frame of 50 years of daily atmospheric inputs. Mercury fate and transport are simulated for three different sources of Hg (cinnabar, residual liquid mercury or aqueous mercuric chloride), as well as for combinations of these sources. Results are presented and discussed with focus on Hg volatilization to the atmosphere, Hg leaching at the bottom of the soil profile and the remaining Hg in or below the initially contaminated soil layer. In the test case, Hg volatilization was negligible because the reduction of Hg(2+) to Hg(0) was inhibited by the low concentration of dissolved Hg. Hg leaching was mainly caused by complexation of Hg(2+) with thiol groups of dissolved organic matter, because in the geochemical model used, this reaction only had a higher equilibrium constant than the sorption reactions. Immobilization of Hg in the initially polluted horizon was enhanced by Hg(2+) sorption onto humic and fulvic acids (which are more abundant than thiols). Potential benefits of the model for risk management and remediation of contaminated sites are discussed. PMID:24928379

Leterme, Bertrand; Blanc, Philippe; Jacques, Diederik

2014-11-01

159

The Effect of Wildfire on Soil Mercury Concentrations in Southern California Watersheds  

PubMed Central

Mercury (Hg) stored in vegetation and soils is known to be released to the atmosphere during wildfires, increasing atmospheric stores and altering terrestrial budgets. Increased erosion and transport of sediments is well-documented in burned watersheds, both immediately post-fire and as the watershed recovers; however, understanding post-fire mobilization of soil Hg within burned watersheds remains elusive. The goal of the current study is to better understand the impact of wildfire on soil-bound Hg during the immediate post-fire period as well as during recovery, in order to assess the potential for sediment-driven transport to and within surface waters in burned watersheds. Soils were collected from three southern California watersheds of similar vegetation and soil characteristics that experienced wildfire. Sampling in one of these watersheds was extended for several seasons (1.5 years) in order to investigate temporal changes in soil Hg concentrations. Laboratory analysis included bulk soil total Hg concentrations and total organic carbon of burned and unburned samples. Soils were also fractionated into a subset of grain sizes with analysis of Hg on each fraction. Low Hg concentrations were observed in surface soils immediately post-fire. Accumulation of Hg coincident with moderate vegetative recovery was observed in the burned surface soils 1 year following the fire, and mobilization was also noted during the second winter (rainy) season. Hg concentrations were highest in the fine-grained fraction of unburned soils; however, in the burned soils, the distribution of soil-bound Hg was less influenced by grain size. The accelerated accumulation of Hg observed in the burned soils, along with the elevated risk of erosion, could result in increased delivery of organic- or particulate-bound Hg to surface waters in post-fire systems. PMID:20936165

Ferreira, Marcia; Mendez, Carolina B.; Navarro, Bridget; Lopez, Sonya; Jay, Jennifer A.

2010-01-01

160

Study on the reduction of atmospheric mercury emissions from mine waste enriched soils through native grass cover in the Mt. Amiata region of Italy  

SciTech Connect

Atmospheric mercury emissions from mine-waste enriched soils were measured in order to compare the mercury fluxes of bare soils with those from other soils covered by native grasses. Our research was conducted near Mt. Amiata in central Italy, an area that was one of the largest and most productive mining centers in Europe up into the 1980s. To determine in situ mercury emissions, we used a Plexiglas flux chamber connected to a portable mercury analyzer (Lumex RA-915+). This allowed us to detect, in real time, the mercury vapor in the air, and to correlate this with the meteorological parameters that we examined (solar radiation, soil temperature, and humidity). The highest mercury flux values (8000 ng m{sup ?2} h{sup ?1}) were observed on bare soils during the hours of maximum insulation, while lower values (250 ng m{sup ?2} h{sup ?1}) were observed on soils covered by native grasses. Our results indicate that two main environmental variables affect mercury emission: solar radiation intensity and soil temperature. The presence of native vegetation, which can shield soil surfaces from incident light, reduced mercury emissions, a result that we attribute to a drop in the efficiency of mercury photoreduction processes rather than to decreases in soil temperature. This finding is consistent with decreases in mercury flux values down to 3500 ng m{sup ?2} h{sup ?1}, which occurred under cloudy conditions despite high soil temperatures. Moreover, when the soil temperature was 28 °C and the vegetation was removed from the experimental site, mercury emissions increased almost four-fold. This increase occurred almost immediately after the grasses were cut, and was approximately eight-fold after 20 h. Thus, this study demonstrates that enhancing wild vegetation cover could be an inexpensive and effective approach in fostering a natural, self-renewing reduction of mercury emissions from mercury-contaminated soils. -- Highlights: ? Mercury air/surface exchange from grass covered soil is different from bare soil. ? Light enhances mercury emissions and is the main parameter driving the process. ? The presence of wild vegetation covering the soil reduces mercury emission. ? Vegetative covers could be a solution to reduce atmospheric mercury pollution.

Fantozzi, L., E-mail: l.fantozzi@iia.cnr.it [CNR-Institute of Atmospheric Pollution Research, c/o: UNICAL-Polifunzionale, 87036 Rende (Italy); Ferrara, R., E-mail: romano.ferrara@pi.ibf.cnr.it [CNR-Institute of Biophysics, San Cataldo Research Area, Via G. Moruzzi 1, 56124 Pisa (Italy); Dini, F., E-mail: fdiniprotisti@gmail.com [University of Pisa, Department of Biology, Via A. Volta 4, 56126 Pisa (Italy); Tamburello, L., E-mail: ltamburello@biologia.unipi.it [University of Pisa, Department of Biology, Via Derna 1, I-56126 Pisa (Italy); Pirrone, N.; Sprovieri, F. [CNR-Institute of Atmospheric Pollution Research, c/o: UNICAL-Polifunzionale, 87036 Rende (Italy)] [CNR-Institute of Atmospheric Pollution Research, c/o: UNICAL-Polifunzionale, 87036 Rende (Italy)

2013-08-15

161

40 CFR Table 5 to Subpart IIIii of... - Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans  

Code of Federal Regulations, 2012 CFR

...2011-07-01 true Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans...Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Pt. 63, Subpt....

2012-07-01

162

40 CFR Table 5 to Subpart IIIii of... - Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans...Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Pt. 63, Subpt....

2011-07-01

163

40 CFR Table 5 to Subpart IIIii of... - Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans...Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Pt. 63, Subpt....

2013-07-01

164

A comparison of mercury levels in feathers and eggs of osprey (Pandion haliaetus) in the North American Great Lakes.  

PubMed

Osprey (Pandion haliaetus) eggs and chick feathers were collected for mercury analysis from nests at four Great Lakes study areas in Ontario (three "naturally formed" lakes in southern Ontario and one reservoir in northern Ontario) and two New Jersey study areas in 1991-1994. Adult osprey feathers were sampled from three Great Lakes study areas in 1991. Feathers sampled from chicks (approximately 28-35 days old) appear to be better indicators of local contaminant conditions since spatial patterns of mercury in known prey, yellow perch (Perca flavescens), also collected in these areas, were more similar to chick feathers than to eggs. Mercury levels were less variable in chick feathers than in eggs. Estimates of biomagnification factors using prey of known size at these areas were also less variable in feathers than in eggs. At naturally formed lakes, no significant correlation in mercury levels between eggs and chick feathers from the same nest was apparent, suggesting that the source of mercury contamination was not the same in these two tissues: mercury levels in eggs reflect mercury acquired on the breeding grounds, wintering grounds, and migratory route; mercury levels in chick feathers reflect local dietary conditions on the breeding grounds. Mercury levels in both osprey eggs and chick feathers were higher at the Ogoki Reservoir than at naturally formed lakes. Adult osprey feathers had higher mercury concentrations than chick feathers. Mercury levels in osprey eggs, chick feathers, and adult feathers did not approach levels associated with toxic reproductive effects. PMID:9419264

Hughes, K D; Ewins, P J; Clark, K E

1997-11-01

165

Mercury Levels in Michigan River Otters, Lutra canadensis  

Microsoft Academic Search

Mercury (Hg) concentrations were examined in kidney and\\/or liver tissues of 43 river otters collected from the upper and northern lower peninsulas of Michigan from 1987–1989. In general, Hg concentrations in Michigan's otters were lower than reported for other localities in the United States but higher than concentrations reported in Michigan fish species. Concentrations were significantly higher in liver tissue

Ramona M. Ropek; Robert K. Neely

1993-01-01

166

Mercury levels of Nelson's and saltmarsh sparrows at wintering grounds in Virginia, USA.  

PubMed

Nelson's and saltmarsh sparrows (Ammodramus nelsoni and A. caudacutus) have recently been recognized as separate species, and because of their limited distributions and the susceptibility of their wetland habitats to climate change, these two new species are of conservation concern. Both species are known to bioaccumulate mercury at breeding sites in New England, USA where their ranges overlap, with the saltmarsh sparrow reported to have twice the concentration of blood total mercury. In this study we sampled both species on their shared wintering grounds, and documented that mercury exposure is lower than that reported for the breeding range, with saltmarsh sparrow blood mercury 2.6 times higher than in Nelson's sparrow. Feather mercury, which is incorporated on the breeding grounds, confirmed that saltmarsh sparrows had incorporated 2.3 times more mercury than Nelson's sparrows during the previous breeding season. A comparison of stable isotopes of nitrogen and carbon suggests that the higher exposure of saltmarsh sparrows may be not due to feeding at a higher trophic level, as previously hypothesized, but rather could be related to a difference in the carbon source at the base of each species' food chain. This study, along with recently published data from both species on additional breeding and wintering grounds, provides a more complete picture of relative mercury exposure. Saltmarsh sparrows are exposed to mercury levels that warrant concern, with the highest exposure being during the breeding season. Areas set aside for the long-term conservation of this species should be carefully assessed for mercury bioaccumulation. PMID:21698442

Cristol, Daniel A; Smith, Fletcher M; Varian-Ramos, Claire W; Watts, Bryan D

2011-11-01

167

Mercury release from deforested soils triggered by base cation enrichment  

E-print Network

-use 1. Introduction In many tropical regions of the world, forests have nearly disappeared or are being-rich ashes from the burning of the vegetation biomass for cultivation to be successful, which leads to forest. Since these soils are naturally very poor in base cations, the burning of the forest biomass suddenly

Long, Bernard

168

Blood Mercury Level and Its Determinants among Dental Practitioners in Hamadan, Iran  

PubMed Central

Objective: Exposure to mercury can occur in occupational and environmental settings. During clinical work with dental amalgam, the dental personnel are exposed to both metallic mercury and mercury vapor. The aim of the present study was to investigate blood mercury level (BML) and its determinants among dentists practicing in Hamadan city, Iran. Materials and Methods: This cross sectional study was done on all dental practitioners of Hamadan (n=43). Dentists were asked to complete a questionnaire, and then 5 ml blood samples were obtained from them. After preparation, mercury concentration of each sample was measured by cold vapor atomic absorption device. Pearson correlation test and regression models served for statistical analysis. Results: The mean blood concentration of mercury was 6.3 ?g/l (SD=1.31 range 4.15–8.93). BML was positively associated with age, years in practice, working hours per day, number of amalgam restorations per day, number of amalgam removal per week, sea food consumption, working years in present office, using amalgam powder, using diamond bur for amalgam removal, dry sterilization of amalgam contaminated instruments, and deficient air ventilation. Conclusion: BML of dentists in Hamadan was higher than standards. Working hours and number of amalgam restorations per day were significantly correlated with blood mercury. PMID:21998776

Kasraei, Sh.; Mortazavi, H.; Vahedi, M.; Bakianian Vaziri, P.; Assary, MJ.

2010-01-01

169

Mercury in polluted soils: speciation using micro-XRF, micro-XRD, and micro- and bulk XAFS.  

NASA Astrophysics Data System (ADS)

In this research, mercury speciation was assessed for soil samples collected inside and outside an industrial polluted area of National environmental interest located in "Val Basento" (Basilicata, Italy). Hg concentration in these soil samples ranged from 12 up to 240 mg/kg. Mercury chemical forms in these samples were identified by a combination of sequential extraction procedures, thermal desorption analyses, and different bulk- and micro-analytical techniques exploiting high intensity synchrotron generated X-rays. Bulk XANES (X-ray Absorption Near Edge Structure) and EXAFS (Extended X-ray Absorption Fine Structure) spectra were collected for direct Hg-speciation in soil samples sieved at 2mm as well as in the clay fraction (<2um), where the highest amount of mercury was concentrated. The interpretation of the complex mixture of Hg-chemical forms in the soil samples was made simpler by performing, beside bulk XAS investigations, microanalyses on soil thin sections by combined u-XRF/u-XRD (micro X-ray Fluorescence/micro X-ray Diffraction) and u-XANES, with a resolution of 20 um. The information deriving from the micro-scale was then used to understand the bulk data. m-XRF maps were collected to localize microscopic Hg-containing particles in areas of several hundreds of mm2. Simultaneous to u-XRF spectra, microdiffraction patterns were collected in each point of the map, to identify possible crystalline Hg-mineral forms or mineral associations. Once points of interest were localized, u-XANES spectra were also collected. In general, two main representative XANES spectra (S1 and S2) were observed from Hg-rich spots at the microscopic level. Interestingly, all the bulk XANES spectra from all soil samples could be fitted by a linear combination of the microscopic S1 and S2 spectra. Therefore, by fitting the S1 and S2 spectra by means of known standard spectra it was then possible to decipher Hg-speciation for all the soil samples. In conclusion, the main constituents in the soil samples were cinnabar (HgS), metacinnabar, corderoite (Hg3S2Cl2), and amorphous Hg-S-Cl phases, in different proportions. The presence of these amorphous forms was suggested by EXAFS and XRD structural analyses. The speciation obtained is also in agreement with the chemical behaviour of the soil samples as assessed by sequential extractions and thermal desorption analyses. The chemical species identified are typical of soils contaminated with wastes produced by chlor-alkali plants. Actually, a chlor-alkali plant was active in the area during the 1960-80's, and now is no more existing. In conclusion, notwithstanding the diffuse Hg-pollution in the investigated area, it seems that Hg is speciated in scarcely soluble and hardly mobilisable forms. The determination of the chemical forms of toxic elements in polluted soils is an indispensable step to identify the source of pollution, to formulate a correct risk assessment and to develop effective remediation strategies.

Terzano, R.; Santoro, A.; Spagnuolo, M.; Vekemans, B.; Medici, L.; Janssens, K.; Goettlicher, J.; Denecke, M. A.; Mangold, S.; Ruggiero, P.

2009-04-01

170

The relationship between Adirondack lake pH and levels of mercury in yellow perch.  

PubMed

Levels of total mercury in yellow perch Perca flavescens from Adirondack lakes were studied in relation to characteristics of the lakes to determine why some lakes had fish with higher concentrations of mercury. Almost all mercury in fish is in the form of methylmercury, which can pose significant health hazards to humans who consume such fish. Fish mercury concentrations and water chemistry data were analyzed from eight Adirondack lakes. Four lakes (Halfmoon Lake, Sand Pond, Rock Pond, and Upper Sister Lake) had pH values of less than 5.0. Four other lakes (Lake Adirondack, Kings Flow, Harris Lake, and Lake Kushaqua) had pH values of more than 7.0. The acidic lakes also had high levels of aluminum and low acid-neutralizing capacity relative to the neutral lakes. Yellow perch (n = 100) from the acidic lakes had significantly higher levels of mercury than did those (n = 102) from the neutral lakes (P < 0.001), and the total mercury concentration increased with both length and weight of the fish. We conclude that the pH of the lake water is a major factor in determining the concentration of methylmercury in yellow perch. PMID:21413513

Brown, Donald; Goncharov, Alexey; Paul, Eric; Simonin, Howard; Carpenter, David O

2010-12-01

171

Water and soil biotic relations in Mercury distribution  

NASA Technical Reports Server (NTRS)

The distribution of Hg is considered both in terms of its availability in soil fractions and the relationship between Hg in plant samples and Hg in ambient soils or other supportive media. The plants were grouped by habitat into epipedic-epiphytic (mosses, lichens) and endopedic-aquatic-marine (Basidiomycetes and algae) samples; nonvascular and vascular forms were also distinguished. Sources included Alaska, Hawaii, New England and Iceland. Brief consideration was also given to Hg distribution in a plant-animal-soil community. Data were expressed in terms of plant Hg content and plant substratum concentration ratio. Average Hg contents and concentration ratios, and modal ranges for the ratios were determined. The results showed similar average Hg contents in all groups (126 to 199 ppb) but a low value (84 ppb) in the lichens; terrestrial forms had ratios of 3.5 to 7.6 whereas the marine algae yielded a figure of 78.7. A secondary mode in the range 0 to 0.1 appeared only in the Alaska-New England Group, over 500 km distant from active thermal sites. Evidence for both exclusion and concentration behavior was obtained.

Siegel, S. M.; Siegel, B. Z.; Puerner, N.; Speitel, T.; Thorarinsson, F.

1975-01-01

172

Relation between Cord Blood Mercury Levels and Early Child Development in a World Trade Center Cohort  

PubMed Central

Objective This study was designed to determine whether prenatal mercury exposure, including potential releases from the World Trade Center (WTC) disaster, adversely affects fetal growth and child development. Methods We determined maternal and umbilical cord blood total mercury of nonsmoking women who delivered at term in lower Manhattan after 11 September 2001, and measured birth outcomes and child development. Results Levels of total mercury in cord and maternal blood were not significantly higher for women who resided or worked within 1 or 2 miles of the WTC in the month after 11 September, compared with women who lived and worked farther away. Average cord mercury levels were more than twice maternal levels, and both were elevated in women who reported eating fish/seafood during pregnancy. Regression analyses showed no significant association between (ln) cord or maternal blood total mercury and birth outcomes. Log cord mercury was inversely associated with the Bayley Scales of Infant Development psychomotor score [Psychomotor Development Index (PDI)] at 36 months (b = –4.2, p = 0.007) and with Performance (b = –3.4, p = 0.023), Verbal (b = –2.9, p = 0.023), and Full IQ scores (b = –3.8, p = 0.002) on the Wechsler Preschool and Primary Scale of Intelligence, Revised (WPPSI-R), at 48 months, after controlling for fish/seafood consumption and other confounders. Fish/seafood consumption during pregnancy was significantly associated with a 5.6- to 9.9-point increase in 36-month PDI, and 48-month Verbal and Full IQ scores. Conclusions Blood mercury was not significantly raised in women living or working close to the WTC site in the weeks after 11 September 2001. Higher cord blood mercury was associated with reductions in developmental scores at 36 and 48 months, after adjusting for the positive effects of fish/seafood consumption during pregnancy. PMID:18709170

Lederman, Sally Ann; Jones, Robert L.; Caldwell, Kathleen L.; Rauh, Virginia; Sheets, Stephen E.; Tang, Deliang; Viswanathan, Sheila; Becker, Mark; Stein, Janet L.; Wang, Richard Y.; Perera, Frederica P.

2008-01-01

173

The development and testing of technologies for the remediation of mercury-contaminated soils, Task 7.52. Topical report, December 1992--December 1993  

SciTech Connect

The release of elemental mercury into the environment from manometers that are used in the measurement of natural gas flow through pipelines has created a potentially serious problem for the gas industry. Regulations, particularly the Land Disposal Restrictions (LDR), have had a major impact on gas companies dealing with mercury-contaminated soils. After the May 8, 1993, LDR deadline extension, gas companies were required to treat mercury-contaminated soils by designated methods to specified levels prior to disposal in landfills. In addition, gas companies must comply with various state regulations that are often more stringent than the LDR. The gas industry is concerned that the LDRs do not allow enough viable options for dealing with their mercury-related problems. The US Environmental Protection Agency has specified the Best Demonstrated Available Technology (BDAT) as thermal roasting or retorting. However, the Agency recognizes that treatment of certain wastes to the LDR standards may not always be achievable and that the BDAT used to set the standard may be inappropriate. Therefore, a Treatability Variance Process for remedial actions was established (40 Code of Federal Regulations 268.44) for the evaluation of alternative remedial technologies. This report presents evaluations of demonstrations for three different remedial technologies: a pilot-scale portable thermal treatment process, a pilot-scale physical separation process in conjunction with chemical leaching, and a bench-scale chemical leaching process.

Stepan, D.J.; Fraley, R.H.; Charlton, D.S.

1994-02-01

174

Where does the mercury in gaseous fluxes from soil come from? An applied stable isotope experiment  

NASA Astrophysics Data System (ADS)

The flux of gaseous mercury from soils is controlled by a number of physico-chemical factors including temperature, soil mercury concentration, boundary layer conditions, soil moisture, and often most notably, solar radiation. It has been presumed that the shallowest soils constitute the main source of Hg for evasion since this Hg is closer to the surface and since the organic horizon and shallow A-horizon soils generally have the most organic matter, where Hg is sorbed and accumulated. The evidence for the predominance of near surface soil as the principal source of Hg for evasion has generally been correlational in nature however and no direct experimental evidence currently exists. This experimental laboratory study directly assessed the depth from which Hg evades by labeling different soil layers (1cm in thickness) with an enriched Hg stable isotope and measuring Hg fluxes under constant, but relatively low light conditions. Fluxes were measured using a dynamic flux chamber coupled to high-precision air pumps and gold traps. The gold traps were thermally desorbed and Hg isotopes were measured by ICP-MS. Under dry soil conditions, we found that most labeled Hg fluxes were very low, with no discernible pattern in relation to tracer depth. In some dry condition measurements where tracer fluxes were significant (up to 69 ng/m2 h), they were four or more times less than measurements made with wetter soils. When soils were wetted to field capacity and then allowed to dry over time, measured surface fluxes peaked approximately 24 hours after wetting and quickly declined. The largest fluxes (270 ng/m2 h) measured after wetting were observed when the isotope enriched layer constituted the surface layer. Significant fluxes were measured after wetting when the enriched layer was at 0, 1 and 2 cm, and fluxes generally decreased exponentially with depth. Fluxes after wetting, when the enriched layer was 5cm below the surface, were non-significant. Our data provide direct evidence to corroborate previous assumptions that the upper 2 cm of soil do indeed constitute the principal zone of Hg source and Hg transport for soil Hg emissions to the atmosphere.

Mazur, Maxwell; Eckley, Chris; Mitchell, Carl

2013-04-01

175

Barium Levels in Soils and Centella asiatica  

PubMed Central

In this study, Centella asiatica and surface soils were collected from 12 sampling sites in Peninsular Malaysia, and the barium (Ba) concentrations were determined. The Ba concentration [?g/g dry weight (dw)] was 63.72 to 382.01 ?g/g in soils while in C. asiatica, Ba concentrations ranged from 5.05 to 21.88 ?g/g for roots, 3.31 to 11.22 ?g/g for leaves and 2.37 to 6.14 ?g/g for stems. In C. asiatica, Ba accumulation was found to be the highest in roots followed by leaves and stems. The correlation coefficients (r) of Ba between plants and soils were found to be significantly positively correlated, with the highest correlation being between roots-soils (r=0.922, p<005), followed by leaves-soils (r=0.890, p<005) and stems-soils (r=0.848, p<005). This indicates that these three parts of C. asiatica are good biomonitors of Ba pollution. For the transplantation study, four sites were selected as unpolluted [(Universiti Putra Malaysia (UPM)], semi-polluted (Seri Kembangan and Balakong) and polluted sites (Juru). Based on the transplantation study under experimental field and laboratory conditions, Ba concentrations in C. asiatica were significantly (p<0.05) higher after three weeks of exposure at Seri Kembangan, Balakong and Juru. Thus, these experimental findings confirm that the leaves, stems and roots of C. asiatica can reflect the Ba levels in the soils where this plant is found. Three weeks after back transplantation to clean soils, the Ba levels in C. asiatica were still higher than the initial Ba level even though Ba elimination occurred. In conclusion, the leaves, stems and roots of C. asiatica are good biomonitors of Ba pollution. PMID:24575242

Ong, Ghim Hock; Yap, Chee Kong; Mahmood, Maziah; Tan, Soon Guan; Hamzah, Suhaimi

2013-01-01

176

Barium Levels in Soils and Centella asiatica.  

PubMed

In this study, Centella asiatica and surface soils were collected from 12 sampling sites in Peninsular Malaysia, and the barium (Ba) concentrations were determined. The Ba concentration [?g/g dry weight (dw)] was 63.72 to 382.01 ?g/g in soils while in C. asiatica, Ba concentrations ranged from 5.05 to 21.88 ?g/g for roots, 3.31 to 11.22 ?g/g for leaves and 2.37 to 6.14 ?g/g for stems. In C. asiatica, Ba accumulation was found to be the highest in roots followed by leaves and stems. The correlation coefficients (r) of Ba between plants and soils were found to be significantly positively correlated, with the highest correlation being between roots-soils (r=0.922, p<005), followed by leaves-soils (r=0.890, p<005) and stems-soils (r=0.848, p<005). This indicates that these three parts of C. asiatica are good biomonitors of Ba pollution. For the transplantation study, four sites were selected as unpolluted [(Universiti Putra Malaysia (UPM)], semi-polluted (Seri Kembangan and Balakong) and polluted sites (Juru). Based on the transplantation study under experimental field and laboratory conditions, Ba concentrations in C. asiatica were significantly (p<0.05) higher after three weeks of exposure at Seri Kembangan, Balakong and Juru. Thus, these experimental findings confirm that the leaves, stems and roots of C. asiatica can reflect the Ba levels in the soils where this plant is found. Three weeks after back transplantation to clean soils, the Ba levels in C. asiatica were still higher than the initial Ba level even though Ba elimination occurred. In conclusion, the leaves, stems and roots of C. asiatica are good biomonitors of Ba pollution. PMID:24575242

Ong, Ghim Hock; Yap, Chee Kong; Mahmood, Maziah; Tan, Soon Guan; Hamzah, Suhaimi

2013-08-01

177

Mapping of mercury contents in soil and air in a decommissioned mining and metallurgical area from the Almadén mercury mining district (Spain): The Almadenejos area.  

NASA Astrophysics Data System (ADS)

Almadenejos is a small town located some 14 km to the East of Almadén, and has been the site of mining and metallurgical activity, linked to the world-class Almadén mercury mining district: the now-abandoned cinnabar (HgS) mines of Vieja Concepción (active in 1699-1800), Nueva Concepción (active in 1794-1861, 1943-1945 and 1960-1967) and El Entredicho (active in Arabs times, and 1981-1997) are located on its neighbourhood, as well as the Almadenejos decommissioned metallurgical precinct (active 1794-1861),what makes the area one of the most contaminated ones of the district. We present here results and maps of a survey including soils sampling with mercury analysis and other pedological parameters, as well as determinations of mercury inmission in the atmosphere, using a common sampling grid. Analysis of soils samples has been carried out using a LUMEX RA-915+ mercury analyser, with RA-91 pyrolysis chamber, and air determinations, using the same RA-915+ device in air analysis mode. The maps have been obtained by means of SURFER 8 software, as well as by ArcGIS software, and puts forward contaminated areas centred inside the metallurgical precinct, with up to 1.5% Hg in soils and up to 20.000 ng Hg•m-3 in the atmosphere.

Martínez-Coronado, A.; Llanos, W.; Oyarzun, R.; Esbrí, J. M.; Higueras, P.

2009-04-01

178

X-ray fluorescence mercury determination using cation selective membranes at sub-ppb levels.  

PubMed

In the present work a method for the determination of mercury at trace levels by energy dispersive X-ray fluorescence (EDXRF) is introduced. Mercury ions were concentrated on cation selective membranes that have been prepared on Mylar(®) thin film substrate, immobilized on plastic cups. The produced membranes were immersed in water solutions containing low concentrations of mercury. The membranes were left to equilibrate in 1000 mL of mercury solutions and were analyzed by EDXRF. The effects of various experimental parameters were examined. Minimum detection limits of pg mL(-1) (ppt) (0.069 ng mL(-1) for ASTM Type I water and 0.064 ng mL(-1) for seawater) and good linearity were achieved. PMID:24418129

Hatzistavros, Vasilios S; Kallithrakas-Kontos, Nikolaos G

2014-01-27

179

Potential risks of natural mercury levels to wild predator fish in an Amazon reservoir.  

PubMed

Mercury (Hg) is a toxic metal that bioaccumulates in aquatic organisms and along food chain. Many studies have reported the problem of mercury exposure in aquatic systems from Amazon basin, but very few have focused on the potential risks to wild fish. The present study reports the bioaccumulation of mercury and alterations in target organs of the predator fish Hoplias malabaricus (traíra) from Samuel reservoir, Amazon basin, Northern Brazil. About 18% of fish had mercury levels in muscle exceeding the safe limit for ingestion through food, established by WHO (0.5 ?g Hg g(-1)). Fish were separated in two groups according to mercury bioaccumulation in liver (<0.2 ?g Hg g(-1)-group I and >0.2 ?g Hg g(-1)-group II) for biomarker comparisons. Catalase activity and number of macrophage centers were statistically higher in group II, confirming the potential of Hg to interfere with redox balance and to recruit defense cells to the liver. Conversely, erythrocyte nuclear alterations were less frequent in group II, indicating a more rigorous selection of erythrocytes or hormesis pattern of response. Glutathione S-transferase activity, lipid peroxidation, and histopathological analyses were not statistically different in the liver and gills of both groups. Comparison of lipid peroxidation levels of these fish with others captured in Southern Brazil during another study and the high incidence of morphological alterations in the liver and gills suggest that the bioaccumulation of mercury during continuous exposure is posing potential risks to the species. PMID:21927790

da Silva, Grazyelle Sebrenski; Filipak Neto, Francisco; Silva de Assis, Helena Cristina; Bastos, Wanderley Rodrigues; de Oliveira Ribeiro, Ciro Alberto

2012-08-01

180

A simulation study of mercury release fluxes from soils in wet-dry rotation environment.  

PubMed

A simulative mesocosm study was conducted to evaluate the influence of wet-dry rotation on mercury (Hg) flux from soil/water to air and the distribution of Hg species in water as well as Hg chemical fractions in soil. Three types of soil were employed including two kinds of paddy soil, Typic Purpli-Udic Cambosols (TPUC) and Xanthi-Udic Ferralosols (XUF), as well as the Alluvial Soil (AS) from Three Gorge reservoir area in Chongqing, China. The results showed that Hg fluxes in wetting periods were significantly higher than that in drying periods. It might be due to the formation of a layer of stable air over the water surface in which some redox reactions promote evasion processes over the water surface. This result indicated that more Hg would be evaporated from the Three Gorge reservoir and paddy soil field during the flooding season. Hg fluxes were positively correlated with air temperature and solar irradiation, while negatively correlated with air humidity and the electronic conductivity of water. Hg fluxes from AS and TPUC were significantly higher than that from XUF, which might be due to the higher organic matter (OM) contents in XUF than TPUC and AS. The reduction processes of oxidized Hg were restrained due to the strong binding of Hg to OM, resulting in the decrease in Hg flux from the soil. PMID:25079993

Liang, Peng; Zhang, Cheng; Yang, Yongkui; Wang, Dingyong

2014-07-01

181

Distributions of Mercury and Phosphorous in Everglades Soils From Water Conservation Area 3A, Florida, U.S.A  

Microsoft Academic Search

Soils in the southern half of Water Conservation Area3A are mostly peats with some organic-rich marls. Mercury contents of 64 surface samples over a500 km2 area average 28.7 ng cc-1 (209 ppb drysediment), which is typical of organic-rich soils. High Hg contents in Everglades fish are therefore notcaused by anomalously high soil Hg. Hg contents showno systematic lateral variation, consistent

Cleone Arfstrom; Andrew W. Macfarlane; Ronald D. Jones

2000-01-01

182

Mercury speciation in a tropical soil association; Consequence of gold mining on Hg distribution in French Guiana  

Microsoft Academic Search

Mercury (Hg) speciation was compared in French Guiana pristine soils and in Hg-contaminated soils impacted by former (~1950's) gold mining activities which used Hg for gold amalgamation. Four selective extractions were performed on soil samples to assess the fraction of Hg present as Hg(II) and bond to organic matter (extracted by NH4OH and KOH), to amorphous iron oxides (ascorbate) and

Stéphane Guedron; Sylvain Grangeon; Bruno Lanson; Michel Grimaldi

2009-01-01

183

40 CFR Table 5 to Subpart IIIii of... - Required Elements of Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans  

Code of Federal Regulations, 2010 CFR

...Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans 5 Table 5 to...Pollutants: Mercury Emissions From Mercury Cell Chlor-Alkali Plants Pt. 63, Subpt...Floor-Level Mercury Vapor Measurement and Cell Room Monitoring Plans Your...

2010-07-01

184

Characterization of soils from an industrial complex contaminated with elemental mercury  

SciTech Connect

Historical use of liquid elemental mercury (Hg(0){sub l}) at the Y-12 National Security Complex in Oak Ridge, TN, USA, resulted in large deposits of Hg(0){sub l} in the soils. The fate and distribution of the spilled Hg(0) are not well characterized. In this study we evaluated analytical tools for characterizing the speciation of Hg in the contaminated soils and then used the analytical techniques to examine the speciation of Hg in two soil cores collected at the site. These include x-ray fluorescence (XRF), soil Hg(0) headspace analysis, and total Hg determination by acid digestion coupled with cold vapor atomic absorption (HgT). XRF was not found to be suitable for evaluating Hg concentrations in heterogeneous soils containing low concentration of Hg or Hg(0) because Hg concentrations determined using this method were lower than those determined by HgT analysis and the XRF detection limit is 20 mg/kg. Hg(0){sub g} headspace analysis coupled with HgT measurements yielded good results for examining the presence of Hg(0){sub l} in soils and the speciation of Hg. The two soil cores are highly heterogeneous in both the depth and extent of Hg contamination, with Hg concentrations ranging from 0.05 to 8400 mg/kg. In the first core, Hg(0){sub l} was distributed throughout the 3.2 m depth, whereas the second core, from a location 12 m away, contained Hg(0){sub l} in a 0.3 m zone only. Sequential extractions showed organically associated Hg dominant at depths with low Hg concentration. Soil from the zone of groundwater saturation showed reducing conditions and the Hg is likely present as Hg-sulfide species. At this depth, lateral Hg transport in the groundwater may be a source of Hg detected in the soil at the deeper soil depths. Overall, characterization of soils containing Hg(0){sub l} is difficult because of the heterogeneous distribution of Hg within the soils. This is exacerbated in industrial facilities where fill materials make up much of the soils and historical and continued reworking of the subsurface has remobilized the Hg. -- Highlights: • Presence of Hg(0) and chemical transformations control the Hg speciation in soil. • Redox reactions can result in the mobilization and sequestration of Hg in soils. • Analysis of soils containing Hg(0) is complex due to sample heterogeneity.

Miller, Carrie L., E-mail: millercl@ornl.gov; Watson, David B.; Lester, Brian P.; Lowe, Kenneth A.; Pierce, Eric M.; Liang, Liyuan

2013-08-15

185

Comparative observations on levels of mercury in scalp hair of humans from different Islands  

NASA Astrophysics Data System (ADS)

Following the Minamata events, an extraordinary number of studies concerning mercury toxicity and human health have been undertaken. Particular attention has been given to the evaluation of the dose-response relationship, i.e., the body burden at which (evaluated through the mercury analyses in blood or hair) the risk of poisoning begins. The results of a comparative study concerning levels of mercury in the hair of fishermen living in small islands who eat seafood more than four times per week show that in two areas only, and only in a few cases in these areas, the mercury in the hair exceeds the limit at which a possible risk could exist. In fact, the limit of 50 mg/g of total mercury in the hair (indicated as the lower limit above which a possible risk could occur) is surpassed by nine fishermen out of a total of 39 at station 1 and by four fishermen out of a total of 26 at station 3. The average value at station 1 is 36.38 mg/g and that at station 3 is 30.31 mg. Many countries have set legal limits of mercury for seafood, but evidently the system does not offer a true protection for man. Only the provisional tolerable weekly intake (PTWI), as repeatedly suggested by WHO, should be considered the best guideline to prevent possibly harmful consequences.

Renzoni, Aristeo

1992-09-01

186

Achieving very low mercury levels in refinery wastewater by membrane filtration.  

SciTech Connect

Microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) membranes were evaluated for their ability to achieve the world's most stringent Hg discharge criterion (<1.3 ng/L) in an oil refinery's wastewater. The membrane processes were operated at three different pressures to demonstrate the potential for each membrane technology to achieve the targeted effluent mercury concentrations. The presence of mercury in the particulate form in the refinery wastewater makes the use of MF and UF membrane technologies more attractive in achieving very low mercury levels in the treated wastewater. Both NF and RO were also able to meet the target mercury concentration at lower operating pressures (20.7 bar). However, higher operating pressures ({ge}34.5 bar) had a significant effect on NF and RO flux and fouling rates, as well as on permeate quality. SEM images of the membranes showed that pore blockage and narrowing were the dominant fouling mechanisms for the MF membrane while surface coverage was the dominant fouling mechanism for the other membranes. The correlation between mercury concentration and particle size distribution was also investigated to understand mercury removal mechanisms by membrane filtration. The mean particle diameter decreased with filtration from 1.1 {+-} 0.0 {micro}m to 0.74 {+-} 0.2 {micro}m after UF.

Urgun Demirtas, M.; Benda, P.; Gillenwater, P. S.; Negri, M. C.; Xiong, H.; Snyder, S. W. (Center for Nanoscale Materials); ( ES)

2012-05-15

187

Chronic effects of low-level mercury and cadmium to goldfish (Carassius Auratus)  

SciTech Connect

During this five and one half year investigation, experiments were performed to determine the effects of nanogram levels of cadmium and mercury on reproductive performance, growth, and tissue residues of goldfish. In addition, embryo-larval bioassays were conducted on these metals to compare the effects of a short-term exposure to a sensitive life-cycle stage (i.e., eggs and larvae) with a sustained exposure to a relatively insensitive life-cycle period (i.e., adult). Reproduction was blocked by the long-term exposure to 0.25 ..mu..g/l mercury and 0.27 ..mu..g/l cadmium. Over the 1972 days, the control fish spawned on eleven occasions, but the experimentals failed to spawn. The metal-induced reproductive impairment continued in the experimentals even after six months in clean water. Growth of the populations exposed to mercury and cadmium was significantly less than that of the control population (P < 0.001). The mercury, cadmium and control populations grew by 229%, 232% and 353%, respectively. Mercury and cadmium continuously accumulated in fish tissues over the entire 1789 days of whole body exposure. Despite exposure to mercury as inorganic metal, organomercury also accumula

Westerman, A.G.

1984-01-01

188

Patterns of bacterial diversity along a long-term mercury-contaminated gradient in the paddy soils.  

PubMed

Mercury (Hg) pollution is usually regarded as an environmental stress in reducing microbial diversity and altering bacterial community structure. However, these results were based on relatively short-term studies, which might obscure the real response of microbial species to Hg contamination. Here, we analysed the bacterial abundance and community composition in paddy soils that have been potentially contaminated by Hg for more than 600 years. Expectedly, the soil Hg pollution significantly influenced the bacterial community structure. However, the bacterial abundance was significantly correlated with the soil organic matter content rather than the total Hg (THg) concentration. The bacterial alpha diversity increased at relatively low levels of THg and methylmercury (MeHg) and subsequently approached a plateau above 4.86 mg kg(-1) THg or 18.62 ng g(-1) MeHg, respectively. Contrasting with the general prediction of decreasing diversity along Hg stress, our results seem to be consistent with the intermediate disturbance hypotheses with the peak biological diversity under intermediate disturbance or stress. This result was partly supported by the inconsistent response of bacterial species to Hg stress. For instance, the relative abundance of Nitrospirae decreased, while that of Gemmatimonadetes increased significantly along the increasing soil THg and MeHg concentrations. In addition, the content of SO4 (2-), THg, MeHg and soil depth were the four main factors influencing bacterial community structures based on the canonical correspondence analysis (CCA). Overall, our findings provide novel insight into the distribution patterns of bacterial community along the long-term Hg-contaminated gradient in paddy soils. PMID:24827389

Liu, Yu-Rong; Wang, Jian-Jun; Zheng, Yuan-Ming; Zhang, Li-Mei; He, Ji-Zheng

2014-10-01

189

Mercury in the soil of two contrasting watersheds in the eastern United States.  

PubMed

Soil represents the largest store of mercury (Hg) in terrestrial ecosystems, and further study of the factors associated with soil Hg storage is needed to address concerns about the magnitude and persistence of global environmental Hg bioaccumulation. To address this need, we compared total Hg and methyl Hg concentrations and stores in the soil of different landscapes in two watersheds in different geographic settings with similar and relatively high methyl Hg concentrations in surface waters and biota, Fishing Brook, Adirondack Mountains, New York, and McTier Creek, Coastal Plain, South Carolina. Median total Hg concentrations and stores in organic and mineral soil samples were three-fold greater at Fishing Brook than at McTier Creek. Similarly, median methyl Hg concentrations were about two-fold greater in Fishing Brook soil than in McTier Creek soil, but this difference was significant only for mineral soil samples, and methyl Hg stores were not significantly different among these watersheds. In contrast, the methyl Hg/total Hg ratio was significantly greater at McTier Creek suggesting greater climate-driven methylation efficiency in the Coastal Plain soil than that of the Adirondack Mountains. The Adirondack soil had eight-fold greater soil organic matter than that of the Coastal Plain, consistent with greater total Hg stores in the northern soil, but soil organic matter - total Hg relations differed among the sites. A strong linear relation was evident at McTier Creek (r(2)?=?0.68; p<0.001), but a linear relation at Fishing Brook was weak (r(2)?=?0.13; p<0.001) and highly variable across the soil organic matter content range, suggesting excess Hg binding capacity in the Adirondack soil. These results suggest greater total Hg turnover time in Adirondack soil than that of the Coastal Plain, and that future declines in stream water Hg concentrations driven by declines in atmospheric Hg deposition will be more gradual and prolonged in the Adirondacks. PMID:24551042

Burns, Douglas A; Woodruff, Laurel G; Bradley, Paul M; Cannon, William F

2014-01-01

190

Mercury in the Soil of Two Contrasting Watersheds in the Eastern United States  

PubMed Central

Soil represents the largest store of mercury (Hg) in terrestrial ecosystems, and further study of the factors associated with soil Hg storage is needed to address concerns about the magnitude and persistence of global environmental Hg bioaccumulation. To address this need, we compared total Hg and methyl Hg concentrations and stores in the soil of different landscapes in two watersheds in different geographic settings with similar and relatively high methyl Hg concentrations in surface waters and biota, Fishing Brook, Adirondack Mountains, New York, and McTier Creek, Coastal Plain, South Carolina. Median total Hg concentrations and stores in organic and mineral soil samples were three-fold greater at Fishing Brook than at McTier Creek. Similarly, median methyl Hg concentrations were about two-fold greater in Fishing Brook soil than in McTier Creek soil, but this difference was significant only for mineral soil samples, and methyl Hg stores were not significantly different among these watersheds. In contrast, the methyl Hg/total Hg ratio was significantly greater at McTier Creek suggesting greater climate-driven methylation efficiency in the Coastal Plain soil than that of the Adirondack Mountains. The Adirondack soil had eight-fold greater soil organic matter than that of the Coastal Plain, consistent with greater total Hg stores in the northern soil, but soil organic matter – total Hg relations differed among the sites. A strong linear relation was evident at McTier Creek (r2?=?0.68; p<0.001), but a linear relation at Fishing Brook was weak (r2?=?0.13; p<0.001) and highly variable across the soil organic matter content range, suggesting excess Hg binding capacity in the Adirondack soil. These results suggest greater total Hg turnover time in Adirondack soil than that of the Coastal Plain, and that future declines in stream water Hg concentrations driven by declines in atmospheric Hg deposition will be more gradual and prolonged in the Adirondacks. PMID:24551042

Burns, Douglas A.; Woodruff, Laurel G.; Bradley, Paul M.; Cannon, William F.

2014-01-01

191

Characterization of soils from an industrial complex contaminated with elemental mercury  

SciTech Connect

Historic use of liquid elemental mercury (Hg(0)l) at the Y-12 National Security Complex in Oak Ridge, TN, USA resulted in large deposits of Hg(0)l in the soils. An evaluation of analytical tools for characterizing the speciation of Hg in the soils at the Y-12 facility was conducted and these tequniques were used to examine the speciation of Hg in two soil cores collect at the site. These include X-ray fluorescence (XRF), soil Hg(0) headspace analysis, and total Hg determination by acid digestion coupled with cold vapor atomic absorption. Hg concentrations determined using XRF, a tool that has been suggestions for quick onsite characterization of soils, were lower than concentrations determined by HgT analysis and as a result this technique is not suitable for the evaluation of Hg concentrations in heterogeneous soils containing Hg(0)l. Hg(0)g headspace analysis can be used to examine the presence of Hg(0)l in soils and when coupled with HgT analysis an understanding of the speciation of Hg in soils can be obtained. Two soil cores collected within the Y-12 complex highlight the heterogeneity in the depth and extent of Hg contamination, with Hg concentrations ranging from 0.05 to 8400 mg/kg. At one location Hg(0)l was distributed throughout 3.2 meters of core whereas the core from a location only 12 meters away only contained Hg(0)l in 0.3 m zone of the core. Sequential extractions, used to examine the forms of Hg in the soils, indicated that at depths within the core that have low Hg concentrations organically associated Hg is dominant. Soil from the zone of groundwater inundation showed reduced characteristics and the Hg is likely present as Hg-sulfide species. At this location it appears that Hg transported within the groundwater is a source of Hg to the soil. Overall the characterization of Hg in soils containing Hg(0) l is difficult due to the heterogeneous distribution within the soils and this challenge is enhanced in industrial facilities in which fill material comprise most of the soils and historical and continuing reworking of the subsurface has remobilized the Hg.

Miller, Carrie L [ORNL; Watson, David B [ORNL; Liang, Liyuan [ORNL; Lester, Brian P [ORNL; Lowe, Kenneth Alan [ORNL; Pierce, Eric M [ORNL

2013-01-01

192

Electronic Characterization of Defects in Narrow Gap Semiconductors-Comparison of Electronic Energy Levels and Formation Energies in Mercury Cadmium Telluride, Mercury Zinc Telluride, and Mercury Zinc Selenide  

NASA Technical Reports Server (NTRS)

We have used a Green's function technique to calculate the energy levels and formation energy of deep defects in the narrow gap semiconductors mercury cadmium telluride (MCT), mercury zinc telluride (MZT) and mercury zinc selenide (MZS). The formation energy is calculated from the difference between the total energy with an impurity cluster and the total energy for the perfect crystal. Substitutional (including antisite), interstitial (self and foreign), and vacancy deep defects are considered. Relaxation effects are calculated (with molecular dynamics). By use of a pseudopotential, we generalize the ideal vacancy model so as to be able to consider relaxation for vacancies. Different charge states are considered and the charged state energy shift (as computed by a modified Haldane-Anderson model) can be twice that due to relaxation. Different charged states for vacancies were not calculated to have much effect on the formation energy. For all cases we find deep defects in the energy gap only for cation site s-like orbitals or anion site p-like orbitals, and for the substitutional case only the latter are appreciably effected by relaxation. For most cases for MCT, MZT, MZS, we consider x (the concentration of Cd or Zn) in the range appropriate for a band gap of 0.1 eV. For defect energy levels, the absolute accuracy of our results is limited, but the precision is good, and hence chemical trends are accurately predicted. For the same reason, defect formation energies are more accurately predicted than energy level position. We attempt, in Appendix B, to calculate vacancy formation energies using relatively simple chemical bonding ideas due to Harrison. However, these results are only marginally accurate for estimating vacancy binding energies. Appendix C lists all written reports and publications produced for the grant. We include abstracts and a complete paper that summarizes our work which is not yet available.

Patterson, James D.

1996-01-01

193

Levels of Cadmium, Lead, Mercury and 137Caesium in Caribou (Rangifer tarandus) Tissues from Northern Québec  

Microsoft Academic Search

Levels of cadmium (Cd), lead (Pb) and total mercury (Hg) were assessed in samples of muscle, kidney, and liver from caribou (Rangifer tarandus; n = 317) harvested in two regions of northern Québec between 1994 and 1996. Levels of 137 caesium (137Cs) were also examined in muscle samples. Log concentration of the three metals varied significantly among tissues and was

S. ROBILLARD; G. BEAUCHAMP; G. PAILLARD; D. BÉLANGER

2002-01-01

194

Relating Land Cover Characteristics and Common Loon Mercury Levels Using Geographic Information Systems  

Microsoft Academic Search

This effort models the relationship between mercury (Hg) levels in the common loon (Gavia immer) and land cover types as defined by the National Land Cover Database (NLCD). We constructed the model within the framework of a GIS to analyze the spatial relationships between land cover types and blood Hg levels in male common loons. Thiessan polygons were used to

David Kramar; Wing M. Goodale; L. M. Kennedy; L. W. Carstensen; Taranjat Kaur

2005-01-01

195

The Level of Mercury in Human Dental Plaque and Interaction in vitro between Biofilms of Streptococcus mutans and Dental Amalgam  

Microsoft Academic Search

Mercury levels (ug\\/mg dry weight) in dental plaque from amalgam and enamel surfaces in human subjects with amalgam restorations were (range, mean, SD) 0.5-1.31, 0.72,0.34 and 0.01-0.54, 0.2, 0.19, respectively. The levels of mercury in plaque from amalgam surfaces were significantly higher than those from plaque on enamel (p < 0.001). No mercury was detected in plaque from subjects without

H. A. Lyttle; G. H. Bowden

1993-01-01

196

Risk, mercury levels, and birds: relating adverse laboratory effects to field biomonitoring.  

PubMed

There is an abundance of field data on levels of mercury in a variety of organisms and there are a number of studies that demonstrate the adverse effects of mercury on laboratory animals, but few studies examine the relationship between the two. Thus it is often difficult to determine the ecological relevance of mercury concentrations found in nature, or to predict the ecosystem consequences of current levels. In this paper we review the levels in tissues that are associated with adverse effects in birds from laboratory studies and compare these with levels found in wild bird populations in the New York Bight to provide a basis for interpreting values in avian populations. We use feathers from fledgling birds which would have been fed on locally obtained food to eliminate the problem of where toxic burdens were acquired by more mobile adult birds. Laboratory studies indicate that in some species mercury levels of 1.5 ppm in eggs and/or 5 to 40 ppm in the feathers of birds are associated with adverse effects, including impaired reproduction. We report egg levels in birds that range as high as 3.8 ppm and feather levels that range as high as 10.3 ppm, although means are much lower. The levels in eggs of some wild birds in the New York Bight are within the range known to lower hatchability, embryo and chick survival, and chick weight, all variables that reduce reproductive success. Species with high egg levels include Forster's tern (Sterna forsteri) and black skimmer (Rynchops niger). Levels in feathers of some young wild birds from the New York Bight are within the range associated with reduced hatchability of eggs, behavioral abnormalities of adults, and infertility. Species with dangerously elevated mercury levels in feathers include great egret (Ardea [=Egretta] alba), snowy egret [Egretta thula), and black skimmers. PMID:9417847

Burger, J; Gochfeld, M

1997-11-01

197

Pituitary gland levels of mercury, selenium, iron, and zinc in an Alzheimer`s disease study  

SciTech Connect

Mercury, iron, selenium, and zinc imbalances have been observed in comparisons between Alzheimer`s disease (AD) and control subject brains. Analyses of the pituitary gland have demonstrated that this organ retains relatively high concentrations of trace elements, including mercury, iron, and zinc. Our previous work has shown that the pituitary glands of AD and control subjects are typically higher in these trace elements than brain samples from the same subject. Instrumental neutron activation analysis (INAA) was used to compare the pituitary trace element levels of AD and control subjects. This study also describes the intrasubject relationships of brain trace element levels to those in the pituitary gland of AD and control subjects.

Cornett, C.R.; Markesbery, W.R.; Wekstein, D.R.; Ehmann, W.D. [Univ. of Kentucky, Lexington, KY (United States)

1996-12-31

198

Mercury accumulation in grass and forb species as a function of atmospheric carbon dioxide concentrations and mercury exposures in air and soil.  

PubMed

The goal of this study was to investigate the potential for atmospheric Hg degrees uptake by grassland species as a function of different air and soil Hg exposures, and to specifically test how increasing atmospheric CO(2) concentrations may influence foliar Hg concentrations. Four common tallgrass prairie species were germinated and grown for 7 months in environmentally controlled chambers using two different atmospheric elemental mercury (Hg major; 3.7+/-2.0 and 10.2+/-3.5 ng m(-3)), soil Hg (<0.01 and 0.15+/-0.08 micro g g(-1)), and atmospheric carbon dioxide (CO(2)) (390+/-18, 598+/-22 micro mol mol(-1)) exposures. Species used included two C4 grasses and two C3 forbs. Elevated CO(2) concentrations led to lower foliar Hg concentrations in plants exposed to low (i.e., ambient) air Hg degrees concentrations, but no CO(2) effect was apparent at higher air Hg degrees exposure. The observed CO(2) effect suggests that leaf Hg uptake might be controlled by leaf physiological processes such as stomatal conductance which is typically reduced under elevated CO(2). Foliar tissue exposed to elevated air Hg degrees concentrations had higher concentrations than those exposed to low air Hg degrees , but only when also exposed to elevated CO(2). The relationships for foliar Hg concentrations at different atmospheric CO(2) and Hg degrees exposures indicate that these species may have a limited capacity for Hg storage; at ambient CO(2) concentrations all Hg absorption sites in leaves may have been saturated while at elevated CO(2) when stomatal conductance was reduced saturation may have been reached only at higher concentrations of atmospheric Hg degrees . Foliar Hg concentrations were not correlated to soil Hg exposures, except for one of the four species (Rudbeckia hirta). Higher soil Hg concentrations resulted in high root Hg concentrations and considerably increased the percentage of total plant Hg allocated to roots. The large shifts in Hg allocation patterns-notably under soil conditions only slightly above natural background levels-indicate a potentially strong role of plants in belowground Hg transformation and cycling processes. PMID:16631233

Millhollen, A G; Obrist, D; Gustin, M S

2006-10-01

199

Projections of atmospheric mercury levels and their effect on air quality in the United States  

NASA Astrophysics Data System (ADS)

The individual and combined effects of global climate change and emissions changes from 2000 to 2050 on atmospheric mercury levels in the United States are investigated by using the global climate-chemistry model, CAM-Chem, coupled with a mercury chemistry-physics mechanism (CAM-Chem/Hg). Three future pathways from the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) are considered, with the A1FI, A1B and B1 scenarios representing the upper, middle and lower bounds of potential climate warming, respectively. The anthropogenic and biomass burning emissions of mercury are projected from the energy use assumptions in the IPCC SRES report. Natural emissions from both land and ocean sources are projected by using dynamic schemes. TGM concentration increases are greater in the low latitudes than they are in the high latitudes, indicative of a larger meridional gradient than in the present day. In the A1FI scenario, TGM concentrations in 2050 are projected to increase by 2.1-4.0 ng m-3 for the eastern US and 1.4-3.0 ng m-3 for the western US. This spatial difference corresponds to potential increases in wet deposition of 10-14 ?g m-2 for the eastern US and 2-4 ?g m-2 for the western US. The increase in Hg(II) emissions tends to enhance wet deposition and hence increase the risk of higher mercury entering the hydrological cycle and ecosystem. In the B1 scenario, mercury concentrations in 2050 are similar to present level concentrations; this finding indicates that the domestic reduction in mercury emissions is essentially counteracted by the effects of climate warming and emissions increases in other regions. The sensitivity analyses show that changes in anthropogenic emissions contribute 32-53% of projected changes in mercury air concentration, while the independent contribution by climate change and its induced natural emissions change accounts for 47-68%.

Lei, H.; Wuebbles, D. J.; Liang, X.-Z.; Tao, Z.; Olsen, S.; Artz, R.; Ren, X.; Cohen, M.

2014-01-01

200

The effects of land use change on mercury distribution in soils of Alta Floresta, Southern Amazon.  

PubMed

This study presents the spatial distribution, degree of contamination and storage capacity of Hg in surface forest and pasture soils from Alta Floresta, Southern Amazon, a significant gold mining site from 1980 to 1996. During that period, average annual gold production was about 6.5 tons, with an estimated Hg annual emission to the environment of about 8.8 tons, 60-80% of it being emitted to the atmosphere. Mercury sources to the region are mining sites and gold-dealer shops at the city of Alta Floresta, where gold is smelted and commercialized. Mercury concentrations in forest soils (15-248 ng g(-1), average=61.9 ng g(-1)) were 1.5-3.0 times higher than in pasture soils (10-74 ng g(-1), average=33.8 ng g(-1)), suggesting strong re-mobilization after deforestation. Highest Hg concentrations were found within a distance of 20-30 km from mining sites in both soil types. The influence of the refining operations within the city of Alta Floresta, however, was less clear. Somewhat higher concentrations were observed only within a 5 km radius from the city center where gold-dealer shops are located. Wind direction controls the spatial distribution of Hg. Background concentrations (15-50 ng g(-1)) were generally found at the outer perimeter of the sampling grid, about 40 km from sources. This suggests that Hg released from mining and refining activities undergoes rapid deposition. Estimated cumulative Hg burdens for the first 10 cm of soil averaged 8.3 mg m(-2) and 4.9 mg m(-2), for forest and pasture soils respectively and compare well with ultisols and hydromorphic oxisols, but were lower than those found in yellow-red and yellow latosols and podsols from other Amazonian areas. Our results show that changing land use in the Amazon is a strong re-mobilizing agent of Hg deposited on soils from the atmosphere. PMID:14987810

Lacerda, Luiz D; de Souza, Margareth; Ribeiro, Mario G

2004-05-01

201

Mercury level in fish caught in Indian River Lagoon higher than it should be?  

E-print Network

Mercury level in fish caught in Indian River Lagoon higher than it should be? Harbor Branch launches new study of humans who eat fish and live around the estuary By Scott Wyland Tuesday, May 22, 2012 INDIAN RIVER COUNTY -- A 20-year-old man fishes local waters every day for his meals and scoffs

Belogay, Eugene A.

202

Human hair mercury levels in Tucuruí area, State of Pará, Brazil.  

PubMed

The environmental mercury contamination at the Tucuruí water reservoir was studied by measuring the amount of mercury in human hair samples collected from fishermen and their families. Samples were also collected from the Parakană Indian reservation in the vicinity to give information about the background levels in the area. The mercury concentrations in hair samples ranged from 0.9 to 240 mg/kg. The mean value in the main reservoir was 65 mg/kg. Seven values exceeded 100 mg/kg and 31 values exceeded 50 mg/kg. The hair Hg concentrations amongst the fishermen in Tucuruí reservoir are high enough to cause health effects. The fetal exposure is especially alarming. Changes in gold mining practises and in the human diet are recommended. PMID:8560241

Leino, T; Lodenius, M

1995-12-11

203

Mercury levels and potential risk from subsistence foods from the Aleutians.  

PubMed

Considerable attention has been devoted to contaminants (mainly PCBs and mercury) in subsistence foods (particularly fish) from various parts of the world. However, relatively little attention has been devoted to examining mercury levels in a full range of subsistence foods from a particular region. While managers and scientists compute risk based on site-specific data on contaminant levels and consumption rates, a first step in making risk decisions by subsistence peoples is knowledge about the relative levels of mercury in the foods they eat. This study examined levels of mercury in subsistence foods (edible components) from several islands in the western Aleutians of Alaska, including algae (4 species), invertebrates (9 species), fish (15 species) and birds (5 species). Samples were gathered by both subsistence hunters/fishers and by scientists using the same equipment. Another objective was to determine if there were differences in mercury levels in subsistence foods gathered from different Aleutian islands. We tested the null hypotheses that there were no interspecific and interisland differences in mercury levels. Because of variation in distribution and the nature of subsistence hunting and fishing, not all organisms were collected from each of the islands. There were significant and important differences in mercury levels among species, but the locational differences were rather small. There was an order of magnitude difference between algae/some invertebrates and fish/birds. Even within fish, there were significant differences. The highest mean mercury levels were in flathead sole (Hippoglossoides elassodon, 0.277 ppm), yellow irish lord (Hemilepidotus jardani, 0.281 ppm), great sculpin (Myoxocephalus polyacanthocephalus, 0.366 ppm), glaucous-winged gull (Larus glaucescens, 0.329 ppm) and its eggs (0.364 ppm), and pigeon guillemot (Cepphus columba, 0.494 ppm). Mercury levels increased with increasing weight of the organisms for limpets (Tectura scutum), and for 11 of the 15 fish species examined. Nine of the 15 fish species had some samples over the 0.3 ppm level, and 7 of 15 fish had some samples over 0.5 ppm. For birds, 95% of the pigeon guillemot muscle samples were above the 0.3 ppm, and 43% were above 0.5 ppm. While health professionals may argue about the risk and benefits of eating fish, and of eating alternative protein sources, the public should be provided with enough information for them to make informed decisions. This is particularly true for subsistence people who consume large quantities of self-caught foods, particularly for sensitive sub-populations, such as pregnant women. We argue that rather than giving people blanket statements about the health benefits or risks from eating fish, information on mean and maximum mercury levels should also be provided on a wide range of subsistence foods, allowing informed decisions, especially by those most at risk. PMID:17590413

Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Burke, Sean; Stamm, Tim; Snigaroff, Ronald; Snigaroff, Dan; Patrick, Robert; Weston, Jim

2007-10-01

204

Air-surface exchange of mercury with soils amended with ash materials  

SciTech Connect

Air-surface exchange of mercury (Hg) was measured from soil low in Hg amended with four different ash materials: a wood ash containing {approximately} 10% coal ash, amixture of two subbituminous coal fly ashes, a subbituminous coal ash containing {approximately} 10% petroleum coke ash and an ash from incinerated municipal sewage sludge (4.3 mg/kg Hg) using a dynamic flux chamber. Ash was added to soil to simulate agricultural supplements, soil stabilization, and pad layers used in livestock areas. For the agricultural amendment, {approximately} 0.4% ash was well mixed into the soil. To make the stabilized soil that could be used for construction purposes, {approximately} 20% ash was mixed into soil with water. The pad layer consisted of a wetted 1-cm layer of ash material on the soil surface. Diel trends of Hg flux were observed for all of the substrates with significantly higher Hg emissions during the day and negligible flux or deposition of Hg during the night. Hg fluxes, which were measured in the summer months, were best correlated with solar radiation, temperature, and air O{sub 3} concentrations. Mean Hg fluxes measured outdoors for unamended soils ranged from 19 to 140 ng/m{sup 2} day, whereas those for soil amended with ash to simulate an agricultural application ranged from 7.2 to 230 ng/m{sup 2} day. Fluxes for soil stabilized with ash ranged from 77 to 530 ng/m{sup 2} day and for soil with pads constructed of ash ranged from -50 to 90 ng/m{sup 2} day. Simple analytical tests were performed to assess whether algorithms based on these tests could be used to predict Hg fluxes observed outdoors using the flux chamber. Based on this study, no consistent relationships could be developed. More work is needed to assess long-term and seasonal variations in Hg flux from substrates before annual estimates of emissions can be developed. 45 refs., 8 figs., 3 tabs.

Jody Ericksen; Mae Sexauer Gustin [University of Nevada-Reno, Reno, NV (United States). Department of Natural Resources and Environmental Sciences

2006-07-15

205

Air-surface exchange of mercury with soils amended with ash materials.  

PubMed

Air-surface exchange of mercury (Hg) was measured from soil low in Hg (0.013 mg/kg) amended with four different ash materials: a wood ash containing -10% coal ash (0.070 mg/kg Hg), a mixture of two subbituminous coal fly ashes (0.075 mg/kg Hg), a subbituminous coal ash containing -10% petroleum coke ash (1.2 mg/kg Hg), and an ash from incinerated municipal sewage sludge (4.3 mg/kg Hg) using a dynamic flux chamber. Ash was added to soil to simulate agricultural supplements, soil stabilization, and pad layers used in livestock areas. For the agricultural amendment, -0.4% ash was well mixed into the soil. To make the stabilized soil that could be used for construction purposes, -20% ash was mixed into soil with water. The pad layer consisted of a wetted 1-cm layer of ash material on the soil surface. Diel trends of Hg flux were observed for all of the substrates with significantly higher Hg emissions during the day and negligible flux or deposition of Hg during the night. Hg fluxes, which were measured in the summer months, were best correlated with solar radiation, temperature, and air O3 concentrations. Mean Hg fluxes measured outdoors for unamended soils ranged from 19 to 140 ng/m2 day, whereas those for soil amended with ash to simulate an agricultural application ranged from 7.2 to 230 ng/m2 day. Fluxes for soil stabilized with ash ranged from 77 to 530 ng/m2 day and for soil with pads constructed of ash ranged from -50 to 90 ng/m2 day. Simple analytical tests (i.e., total Hg content, synthetic precipitation leaching procedure, heating, and indoor gas-exchange experiments) were performed to assess whether algorithms based on these tests could be used to predict Hg fluxes observed outdoors using the flux chamber. Based on this study, no consistent relationships could be developed. More work is needed to assess long-term and seasonal variations in Hg flux from (intact and disturbed) substrates before annual estimates of emissions can be developed. PMID:16878589

Ericksen, Jody; Gustin, Mae Sexauer

2006-07-01

206

Bioaccumulation of trace mercury in trophic levels of benthic, benthopelagic, pelagic fish species, and sea birds from Arvand River, Iran.  

PubMed

In this study, concentration of mercury was determined in the trophic levels of benthic, benthopelagic, pelagic fish species, and river birds from Arvand River, located in the Khuzestan province in the lowlands of southwestern Iran at the head of the Persian Gulf. The order of mercury concentrations in tissues of the fish species was as follows: liver>gill>muscle and in tissues of the kingfisher species was as follows: feather>liver>kidney>muscle. Therefore, liver in fish and feather in kingfisher exhibited higher mercury concentration than the other tissues. There was a positive correlation between mercury concentrations in fish and kingfisher species with size of its food items. We expected to see higher mercury levels in tissues of female species because they are larger and can eat larger food items. The results of this study show that the highest mean mercury level were found in the kingfisher (Anas crecca), followed by benthic (Epinephelus diacanthus), benthopelagic (Chanos chanos), and pelagic fish (Strongylura strongylura). Mean value of mercury in fish species, S. strongylura were (0.61 ?g g(-1) dry weight), C. chanos (0.45 ?g g(-1) dry weight), E. diacanthus (0.87 ?g g(-1) dry weight), and in kingfisher species A. crecca was (2.64 ?g g(-1) dry weight). Significant correlation between mercury concentration in fish and kingfisher may be related to high variability of mercury in the fish. PMID:24174062

Hosseini, Mehdi; Nabavi, Seyed Mohammad Bagher; Parsa, Yaghob

2013-12-01

207

Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques.  

PubMed

Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg(-1). Hg chemical forms were identified and quantified by sequential extractions and bulk- and micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as mu-XRF, mu-XRD and mu-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 microm. The main Hg-species found in the soil samples were metacinnabar (beta-HgS), cinnabar (alpha-HgS), corderoite (Hg(3)S(2)Cl(2)), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 microm. No interaction among Hg-species and soil components was observed. All the observed Hg-species originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution. PMID:20605298

Terzano, Roberto; Santoro, Anna; Spagnuolo, Matteo; Vekemans, Bart; Medici, Luca; Janssens, Koen; Göttlicher, Jörg; Denecke, Melissa A; Mangold, Stefan; Ruggiero, Pacifico

2010-08-01

208

Immobilization of mercury in field soil and sediment using carboxymethyl cellulose stabilized iron sulfide nanoparticles  

NASA Astrophysics Data System (ADS)

Mercury (Hg) is one of the most pervasive and bio-accumulative metals in the environment. Yet, effective in situ remediation technologies have been lacking. This study investigated the effectiveness of a class of soil-deliverable FeS nanoparticles for in situ immobilization of Hg in two field-contaminated soils from a New Jersey site and one sediment from an Alabama site. The nanoparticles were prepared using sodium carboxymethyl cellulose (CMC) as a stabilizer. Transmission electron microscopy measurements revealed a particle size of 34.3 ± 8.3 nm (standard deviation), whereas dynamic light scattering gave a hydrodynamic diameter of 222.5 ± 3.2 nm. Batch tests showed that at an FeS-to-Hg molar ratio of 28:1-118:1, the nanoparticles reduced water-leachable Hg by 79%-96% and the TCLP (toxicity characteristic leaching procedure) based leachability by 26%-96%. Column breakthrough tests indicated that the nanoparticles were deliverable in the sediment/soil columns under moderate injection pressure. However, once the external pressure was removed, the delivered nanoparticles remained virtually mobile under typical groundwater flow conditions. When the Hg-contaminated soil and sediment were treated with 52-95 pore volumes of a 500 mg l-1 FeS nanoparticle suspension, water-leachable Hg was reduced by 90%-93% and TCLP-leachable Hg was reduced by 65%-91%. The results warrant further field demonstration of this promising in situ remediation technology.

Gong, Yanyan; Liu, Yuanyuan; Xiong, Zhong; Kaback, Dawn; Zhao, Dongye

2012-07-01

209

Mercury concentrations in forest soils and stream waters in northeast and south China.  

PubMed

Atmospheric deposition of mercury (Hg) is generally higher in China than in North America and Europe. Transport and methylation of Hg deposited in forest ecosystems may cause health risks to humans. We collected water samples from 117 small streams, and soil samples from 25 sites in forested areas in northeast and south China during 2011-2013 to investigate the spatial distribution of Hg. Results showed that Hg concentration in surface soil (0-5 cm in depth) was generally higher in south China (97.8 ± 36.0 ?g/kg) than that in the northeast (44.0 ± 14.1 ?g/kg). In contrast, the Hg concentration in stream water was higher in northeast China (17.2 ± 11.0 ng/L) than that in the south (6.2 ± 6.4 ng/L). Hg concentrations in surface soil were positively correlated with Hg concentrations in the overlying litter Oe/Oa horizon (r(2)=0.84). Hg concentrations in stream water were positively correlated to DOC (dissolved organic carbon) concentrations (r(2)=0.43) and to the Hg concentration in the litter Oe/Oa horizon (r(2)=0.69). Because the litter Oe/Oa horizon represents Hg accumulated by foliage, the positive correlations indicate that atmospheric Hg deposition was an important factor affecting Hg concentrations in soils and stream water. PMID:25063712

Luo, Yao; Duan, Lei; Wang, Long; Xu, Guangyi; Wang, Shuxiao; Hao, Jiming

2014-10-15

210

Feasibility study of the use of different extractant agents in the remediation of a mercury contaminated soil from Almaden  

Microsoft Academic Search

The soil of Almaden mining district in Spain has a high concentration of mercury (1000mgkg?1), therefore decontamination activities are necessary. This paper studies the effectiveness of some chelant agents (thiosulfate, EDTA, iodide and HNO3) for the remediation of this soil which has been polluted for several millennia. The risk assessment of the contamination and the feasibility study (RA-FS) of the

J. D. Subirés-Muńoz; A. García-Rubio; C. Vereda-Alonso; C. Gómez-Lahoz; J. M. Rodríguez-Maroto; F. García-Herruzo; J. M. Paz-García

2011-01-01

211

A gravimetric approach to providing SI traceability for concentration measurement results of mercury vapor at ambient air levels  

NASA Astrophysics Data System (ADS)

Current measurement and calibration capabilities for mercury vapor in air are maintained at levels of 0.2–40??g?Hg?m?3. In this work, a mercury vapor generator has been developed to establish metrological traceability to the international system of units (SI) for mercury vapor measurement results ?15?ng?Hg?m?3, i.e. closer to realistic ambient air concentrations (1–2?ng?Hg?m?3) [1]. Innovations developed included a modified type of diffusion cell, a new measurement method to weigh the loss in (mercury) mass of these diffusion cells during use (ca. 6–8??g mass difference between successive weighings), and a new housing for the diffusion cells to maximize flow characteristics and to minimize temperature variations and adsorption effects. The newly developed mercury vapor generator system was tested by using diffusion cells generating 0.8 and 16?ng?Hg?min?1. The results also show that the filter system, to produce mercury free air, is working properly. Furthermore, and most importantly, the system is producing a flow with a stable mercury vapor content. Some additional improvements are still required to allow the developed mercury vapor generator to produce SI traceable mercury vapor concentrations, based upon gravimetry, at much lower concentration levels and reduced measurement uncertainties than have been achieved previously. The challenges to be met are especially related to developing more robust diffusion cells and better mass measurement conditions. The developed mercury vapor generator will contribute to more reliable measurement results of mercury vapor at ambient and background air levels, and also to better safety standards and cost reductions in industrial processes, such as the liquefied natural gas field, where aluminum main cryogenic heat exchangers are used which are particularly prone to corrosion caused by mercury.

Ent, Hugo; van Andel, Inge; Heemskerk, Maurice; van Otterloo, Peter; Bavius, Wijnand; Baldan, Annarita; Horvat, Milena; Brown, Richard J. C.; Quétel, Christophe R.

2014-11-01

212

Mercury contamination in human hair and fish from Cambodia: levels, specific accumulation and risk assessment.  

PubMed

Mercury (Hg) concentrations in human hair and fish samples from Phnom Penh, Kien Svay, Tomnup Rolork and Batrong, Cambodia, collected in November 1999 and December 2000 were determined to understand the status of contamination, and age- and sex-dependent accumulation in humans and to assess the intake of mercury via fish consumption. Mercury concentrations in human hair ranged from 0.54 to 190mug/g dry wt. About 3% of the samples contained Hg levels exceeding the no observed adverse effects level (NOAEL) of WHO (50mug/g) and the levels in some hair samples of women also exceeded the NOAEL (10mug/g) associated with fetus neurotoxicity. A weak but significant positive correlation was observed between age and Hg levels in hair of residents. Mercury concentrations in muscle of marine and freshwater fish from Cambodia ranged from <0.01 to 0.96mug/g wet wt. Mercury intake rates were estimated on the basis of the Hg content in fish and daily fish consumption. Three samples of marine fish including sharp-tooth snapper and obtuse barracuda, and one sample of sharp-tooth snapper exceeded the guidelines by US EPA and by Joint FAO/WHO Expert Committee on Food Additives (JECFA), respectively, which indicates that some fish specimens examined (9% and 3% for US EPA and JECFA guidelines, respectively) were hazardous for consumption at the ingestion rate of Cambodian people (32.6g/day). It is suggested that fish is probably the main source of Hg for Cambodian people. However, extremely high Hg concentrations were observed in some individuals and could not be explained by Hg intake from fish consumption, indicating some other contamination sources of Hg in Cambodia. PMID:15572226

Agusa, Tetsuro; Kunito, Takashi; Iwata, Hisato; Monirith, In; Tana, Touch Seang; Subramanian, Annamalai; Tanabe, Shinsuke

2005-03-01

213

Risks associated with the transfer of toxic organo-metallic mercury from soils into the terrestrial feed chain.  

PubMed

Although the transfer of organo-metallic mercury (OrgHg) in aquatic food webs has long been studied, it has only been recently recognized that there is also accumulation in terrestrial systems. There is still however little information about the exposure of grazing animals to OrgHg from soils and feed as well as on risks of exposure to animal and humans. In this study we collected 78 soil samples and 40 plant samples (Lolium perenne and Brassica juncea) from agricultural fields near a contaminated industrial area and evaluated the soil-to-plant transfer of Hg as well as subsequent trophic transfer. Inorganic Hg (IHg) concentrations ranged from 0.080 to 210mgkg(-1) d.w. in soils, from 0.010 to 84mgkg(-1) d.w. in roots and from 0.020 to 6.9mgkg(-1) d.w. in shoots. OrgHg concentrations in soils varied between 0.20 and 130?gkg(-1) d.w. representing on average 0.13% of the total Hg (THg). In root and shoot samples OrgHg comprised on average 0.58% (roots) and 0.66% (shoots) of THg. Average bioaccumulation factors (BAFs) for OrgHg in relation to soil concentrations were 3.3 (for roots) and 1.5 (for shoots). The daily intake (DI) of THg in 33 sampling sites exceeded the acceptable daily intake (ADI) of THg of both cows (ADI=1.4mgd(-1)) and sheep (ADI=0.28mgd(-1)), in view of food safety associated with THg in animal kidneys. Estimated DI of OrgHg for grazing animals were up to 220?gd(-1) (for cows) and up to 33?gd(-1) (for sheep). This study suggested that solely monitoring the levels of THg in soils and feed may not allow to adequately taking into account accumulation of OrgHg in feed crops and properly address risks associated with OrgHg exposure for animals and humans. Hence, the inclusion of limits for OrgHg in feed quality and food safety legislation is advised. PMID:23917441

Henriques, Bruno; Rodrigues, S M; Coelho, C; Cruz, N; Duarte, A C; Römkens, P F A M; Pereira, E

2013-09-01

214

Urinary mercury levels in females: Influence of skin-lightening creams and dental amalgam fillings  

Microsoft Academic Search

The influence of application of skin-lightening creams and dental amalgam fillings on the urinary mercury (Hg) level was evaluated in 225 females (ages 17 to 58 years) living in Riyadh, capital of Saudi Arabia. The arithmetic mean of the urinary Hg level was 6.96 ± 20.43 µg l, in the range 0 to 204.8 µg l. The mean urinary Hg

Iman Al-Saleh; Neptune Shinwari

1997-01-01

215

Impact of soil properties on critical concentrations of cadmium, lead, copper, zinc, and mercury in soil and soil solution in view of ecotoxicological effects.  

PubMed

Risk assessment for metals in terrestrial ecosystems, including assessments of critical loads, requires appropriate critical limits for metal concentrations in soil and soil solution. This chapter presents an overview of methodologies used to derive critical (i) reactive and total metal concentrations in soils and (ii) free metal ion and total metal concentrations in soil solution for Cd, Pb, Cu, Zn, and Hg, taking into account the effect of soil properties related to ecotoxicological effects. Most emphasis is given to the derivation of critical free and total metal concentrations in soil solution, using available NOEC soil data and transfer functions relating solid-phase and dissolved metal concentrations. This approach is based on the assumption that impacts on test organisms (plants, microorganisms, and soil invertebrates) are mainly related to the soil solution concentration (activity) and not to the soil solid-phase content. Critical Cd, Pb, Cu, Zn, and Hg concentrations in soil solution vary with pH and DOC level. The results obtained are generally comparable to those derived for surface waters based on impacts to aquatic organisms. Critical soil metal concentrations, related to the derived soil solution limits, can be described as a function of pH and organic matter and clay content, and varying about one order of magnitude between different soil types. PMID:17708072

de Vries, Wim; Lofts, Steve; Tipping, Ed; Meili, Markus; Groenenberg, Jan E; Schütze, Gudrun

2007-01-01

216

Parameterizing soil emission and atmospheric oxidation-reduction in a model of the global biogeochemical cycle of mercury.  

PubMed

Using the GEOS-Chem atmosphere-land-ocean coupled mercury model, we studied the significances of two processes, soil emission and atmospheric oxidation-reduction, in the global biogeochemical cycling of mercury and their parametrization to improve model performance. Implementing an empirical equation for soil emission flux (Esoil) including soil mercury concentration, solar radiation, and surface air temperature as parameters enabled the model to reproduce the observed seasonal variations of Esoil, whereas the default setting, which uses only the former two parameters, failed. The modified setting of Esoil also increased the model-simulated atmospheric concentration in the summertime surface layer of the lower- and midlatitudes and improved the model reproducibility for the observations in Japan and U.S. in the same period. Implementing oxidation of atmospheric gaseous elemental mercury (Hg(0)) by ozone with an updated rate constant, as well as the oxidation by bromine atoms (Br) in the default setting, improved the model reproducibility for the dry deposition fluxes observed in Japan. This setting, however, failed to reproduce the observed seasonal variations of atmospheric concentrations in the Arctic sites due to the imbalance between oxidation and reduction, whereas the model with Br as the sole Hg(0) oxidant in the polar atmosphere could capture the variations. PMID:24053722

Kikuchi, Tetsuro; Ikemoto, Hisatoshi; Takahashi, Katsuyuki; Hasome, Hisashi; Ueda, Hiromasa

2013-11-01

217

Changes in premature infant mercury and lead blood levels after blood transfusions.  

PubMed

Objective?To describe the blood level changes of mercury and lead after packed red blood cell (PRBC) transfusions in???750?g birth weight infants. Study Design?Heavy metal blood levels were measured in infants in PRBC units on 1st, 4th, 5th, and 7th days (D1, D4, D5, and D7) of life and in urine on D1, D4, and D7. Results?A total of 10 infants were enrolled with a mean birth weight of 632?±?72 g. Out of which nine infants received one or more PRBC transfusions, with an average of 2.9?±?2.5 transfusions per infant. Heavy metals were detected in all the transfusions. The average mercury level was 1.33 µg/L on D1 and 1.66 µg/L on D7, p?>?0.05. The average lead level was 0.32 µg/dL on D1 and 0.56 µg/dL on D7, p?>?0.05. Urinary mercury excretion increased in infants with no bowel movements. Urinary excretion of lead decreased over time as blood levels increased. Conclusions?After receiving blood transfusions, the blood levels of mercury and lead were maintained at the end of the 1st week of life. As there is no evidence of a proportionate increase in excretory amounts of these heavy metals, there is a concern that they are retained and potentially exert toxic effects. PMID:24347256

Elabiad, Mohamad T; Christensen, Michael

2014-11-01

218

SPATIAL VARIATION AND CORRELATIONS OF MERCURY LEVELS IN THE TERRESTRIAL AND AQUATIC COMPONENTS OF A  

E-print Network

of Kejimkujik Park, Nova Scotia. Mercury concentrations in five-year-old yellow perch (age based on regression with mercury in lake waters and yellow perch. No correlations were observed between mercury in terrestrial components and mercury in yellow perch; however, mercury in yellow perch was correlated with P in leaf

O'Driscoll, Nelson

219

Estimation and Mapping of Wet and Dry Mercury Deposition Across Northeastern North America  

Microsoft Academic Search

Whereas many ecosystem characteristics and processes influence mercury accumulation in higher trophic-level organisms, the mercury flux from the atmosphere to a lake and its watershed is a likely factor in potential risk to biota. Atmospheric deposition clearly affects mercury accumulation in soils and lake sediments. Thus, knowledge of spatial patterns in atmospheric deposition may provide information for assessing the relative

Eric K. Miller; Alan Vanarsdale; Gerald J. Keeler; Ann Chalmers; Laurier Poissant; Neil C. Kamman; Raynald Brulotte

2005-01-01

220

MERCURY FLUX MEASUREMENTS OVER AIR AND WATER IN KEJIMKUJIK NATIONAL PARK, NOVA SCOTIA  

E-print Network

MERCURY FLUX MEASUREMENTS OVER AIR AND WATER IN KEJIMKUJIK NATIONAL PARK, NOVA SCOTIA F. S. BOUDALA. Mercury flux measurements were conducted at two lakes and three soil sites in Kejimkujik National Park, located in the eastern Canadian province of Nova Scotia. One of the lakes had high levels of both mercury

Folkins, Ian

221

Concentration and spatial variability of mercury and other heavy metals in surface soil samples of periurban waste mine tailing along a transect in the Almadén mining district (Spain)  

NASA Astrophysics Data System (ADS)

Mercury (Hg) is one of the elements with increasing environmental significance. A total of 22 samples (soils, rocks and gels) were collected along a 6 km transect around the Valdeazogues River valley in the southwest of the Iberian Peninsula (Almadén, Spain). Samples were characterized by different soil types of depositional sequences associated with mining tailings, type and system tracts: 15 surface soil samples included in the transect; 3 of a Haploxerept soil profile developed on slates; 2 of quartzite and slates rocks (reference rocks in the area). Moreover, two of a gel substance (in the lower tract of the river). Soil samples were analyzed for Hg, Cu, Ni, Cr, V, Pb, Cd and As, as well as for organic matter, pH abrasion and calcium carbonate content. All samples were collected from the Almadén mining district. The level of occurrence of the elements (especially Hg) and the effect of some properties on its concentration distributions were investigated. The total mercury contents varied in the range 7,315-3.44 mg kg-1. The mean concentration of total mercury in soils and rocks was 477.03 mg kg-1dry mass. This value is very high compared to the regional background value of other areas. Only rarely is it higher than 1%: in one sample (7,315 mg kg-1) it was almost eight times in comparison with the affected zones, with a high value of 1,000 mg kg-1. Significant differences between samples were found in the total content of mercury. A large percentage of the samples registered detectable levels of V, Cr, Ni, Pb, As and Cu. Cd readings were below the detectable range for all samples tested. Cr mean concentration was 216.95 mg kg-1 (minimun concentration 86, maximun 358); V mean concentration was 119.09 mg kg-1 (minimun concentration 69, maximun 1,209); As mean concentration was 51.24 mg kg-1 (minimun 13.3 and maximun 319.4); Ni mean concentration was 45.64 mg kg-1 (minimun concentration 21.2 and maximun 125.6); Cu mean concentration was 33.25 mg kg-1 (minimun concentration 19.3 and maximun 135); Pb mean concentration was 15.19 mg kg-1 (minimun 1.12 and maximun 1013). Metal distribution generally showed spatial variability ascribed to significant anthropogenic perturbation by mining tailing type. Hg showed vertical profile characterized by surface enrichment, with concentrations in the upper layer (93.7-82.2 mg kg-1 in front of 3.4 of the rock value) exceeding, in several occasions, the background value. The results obtained denote a potential toxicity of some heavy metals in some of the studied samples. Water-soluble mercury could enter the aquatic system and accumulate in sediments. Mercury and other heavy metals contamination depended on the duration and intensity of mining activities.

Bueno, P. Conde; Bellido, E.; Rubí, J. A. Martín; Ballesta, R. Jiménez

2009-01-01

222

Soil organic carbon buffers heavy metal contamination on semiarid soils: Effects of different metal threshold levels on soil microbial activity  

Microsoft Academic Search

Traditionally, three threshold levels have been accepted for heavy metal concentrations in agricultural soils, depending on soil pH. The aim of this work was to ascertain how the three threshold values proposed for Cd (3, 6.5, and 12.5 mg kg?1) and Zn (300, 650, and 1300 mg kg?1) really affect soil microbial activity. Two soils, a scrubland soil and a forest soil, differing widely

J. L. Moreno; F. Bastida; M. Ros; T. Hernández; C. García

2009-01-01

223

Mercury Contamination of Aquatic Ecosystems  

NSDL National Science Digital Library

This United States Geological Survey (USGS) factsheet contains information about US mercury contamination. Issues discussed include how mercury becomes a toxicological problem through bioaccumulation, human effects of mercury toxicity, and levels of atmospheric mercury. Mercury levels in fish are examined to determine how mercury gets into the environment and into the food chain.

Krabbenhoft, D. P.; Rickert, D. A.

224

FIELD MEASUREMENT TECHNOLOGY FOR MERCURY IN SOIL AND SEDIMENT OHIO LUMEX'S RA-915+/RP-91C MERCURY ANALYZER  

EPA Science Inventory

Ohio Lumex's RA915+/91 C mercury analyzer was demonstrated under the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation Program in May 2003, at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The purpose of the Demonstration was to c...

225

DNA barcodes reveal species-specific mercury levels in tuna sushi that pose a health risk to consumers  

PubMed Central

Excessive ingestion of mercury—a health hazard associated with consuming predatory fishes—damages neurological, sensory-motor and cardiovascular functioning. The mercury levels found in Bigeye Tuna (Thunnus obesus) and bluefin tuna species (Thunnus maccoyii, Thunnus orientalis, and Thunnus thynnus), exceed or approach levels permissible by Canada, the European Union, Japan, the US, and the World Health Organization. We used DNA barcodes to identify tuna sushi samples analysed for mercury and demonstrate that the ability to identify cryptic samples in the market place allows regulatory agencies to more accurately measure the risk faced by fish consumers and enact policies that better safeguard their health. PMID:20410032

Lowenstein, Jacob H.; Burger, Joanna; Jeitner, Christian W.; Amato, George; Kolokotronis, Sergios-Orestis; Gochfeld, Michael

2010-01-01

226

Critical levels of atmospheric pollution: criteria and concepts for operational modelling of mercury in forest and lake ecosystems  

Microsoft Academic Search

Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European efforts

Markus Meili; Kevin Bishop; Lage Bringmark; Kjell Johansson; John Munthe; Harald Sverdrup; Wim de Vries

2003-01-01

227

Characterization of mercury species in soils by HPLC-ICP-MS and measurement of fraction removed by diffusive gradient in thin films.  

PubMed

The properties and behaviour of Hg depend on both the oxidation state and the chemical form: the bioavailability, toxicity, persistence and accumulation of mercury in the food web are strongly influenced by chemical speciation. The present work aims to determine the chemical forms of mercury present in soil and to evaluate the fraction of mercury in soil solution available to plants. In order to do this, we analyzed eight samples of contaminated soils with Hg concentrations ranging from 1.31 to 21.7 mg kg(-1), collected from different depths (0-10 and 40-50 cm) close to an abandoned industrial site in Val Basento (southern Italy). Two innovative analytical techniques were used: HPLC-ICP-MS and diffusive gradient in thin films (DGT). The analytical procedure was validated using ERM 580-certified sediment and spiked samples in the case of HPLC-ICP-MS, and by a performance test in the case of DGT. In all samples, the only species found in soil and soil solution was MeHg(+) and Hg(2+). In soil, the MeHg(+)/Hg(tot) ratio ranged from 0.05% to 0.82%; total mercury in soil solution was less than 0.01% of total mercury in soil. The percentage of MeHg(+) in soil solution varied considerably (from 0% to 50%), with a maximum concentration of 0.02 mg L(-1). The root available concentration evaluated by DGT is comparable to the total mercury content of the soil solution measured by HPLC-ICP-MS. The DGT results suggest that all mercury in solution is available for uptake in DGT, and that mercury is supplied from soil to solution. However, for all samples the soluble and root available (DGT-labile) fractions of mercury are generally very low with respect to the total mercury concentration. This study confirmed that both HPLC-ICP-MS and DGT techniques are suitable tools for the estimation of Hg root availability and in assessing the risk from contaminated soils. PMID:18371812

Cattani, I; Spalla, S; Beone, G M; Del Re, A A M; Boccelli, R; Trevisan, M

2008-02-15

228

Fate and transport of mercury in soil systems : a numerical model in HP1 and sensitivity analysis  

NASA Astrophysics Data System (ADS)

Mercury (Hg) poses threats for human health and the environment, notably due to its persistence and its ability to bioaccumulate in ecosystems. Anthropogenic activities are major contributors of mercury release to soils. Main sources of contamination include manufacturing (chlor-alkali plants, manometer spill), mine tailings from mercury, gold and silver mining industries, wood preservation. The objective of this study was to develop a reactive transport model for simulating mercury fate and transport in the unsaturated zone, and to gain insight in the fate and transport of Hg following anthropogenic soil contamination. The present work is done in the framework of the IMaHg project, which aims at providing recommendations to improve management of sites contaminated by mercury within the SNOWMAN funding framework. A model of mercury fate and transport in soil systems was developed using the reactive transport code HP1 (Jacques and Šim?nek, 2010). The geochemical database THERMODDEM (Blanc et al., 2012) is used, augmented with some speciation data from (Skyllberg, 2012). The main processes accounted for in the model are : Hg aqueous speciation (including complexation with dissolved organic matter (DOM) - humic and fulvic acids, and thiol groups), Hg sorption to solid organic matter (SOM), dissolution of solid phase Hg (e.g. cinnabar HgS(s)), dissolution of Hg non-aqueous liquid phase (NAPL), sunlight-driven Hg(II) reduction to Hg(0), Hg(0) diffusion in the gas phase and volatilization, DOM sorption to soil minerals. Colloid facilitated transport is implicitly accounted for by solute transport of Hg-DOM complexes. Because we focused on soil systems having a high Hg contamination, some processes showing relatively smaller Hg fluxes could be neglected such as vegetation uptake and atmospheric wet and dry deposition. NAPL migration and entrapment is not modelled, as pollution is assumed to be historical and only residual NAPL to be present. Mercury methylation and demethylation was not implemented, because it could be neglected in an oxidising environment. However, if the model is to be tested in more reducing conditions (e.g. shallow groundwater table), methyl- and dimethylmercury formation can be non negligible. Using 50 year time series of daily weather observations in Dessel (Belgium) and a typical sandy soil with deep groundwater (free drainage, oxic conditions), a sensitivity analysis was performed to assess the relative importance of processes and parameters within the model. We used the elementary effects method (Morris, 1991; Campolongo et al., 2007), which draws trajectories across the parameter space to derive information on the global sensitivity of the selected input parameters. The impact of different initial contamination phases (solid, NAPL, aqueous and combinations of these) was also tested. Simulation results are presented in terms of (i) Hg volatilized to the atmosphere; (ii) Hg leached out of the soil profile; (iii) Hg still present in the soil horizon originally polluted; and (iv) Hg still present in the soil profile but below the original contaminated horizon. Processes and parameters identified as critical based on the sensitivity analysis differ from one scenario to the other ; depending on pollution type (cinnabar, NAPL, aqueous Hg), on the indicator assessed and on time (after 5, 25 or 50 years). However, in general DOM in soil water was the most critical parameter. Other important parameters were those related to Hg sorption on SOM (thiols, and humic and fulvic acids), and to Hg complexation with DOM. Initial Hg concentration was also often identified as a sensitive parameter. Interactions between factors and non linear effects as measured by the elementary effect method were generally important, but also dependent on the type of contamination and on time. No model calibration was performed until now. The numerical tool could greatly benefit from partial model calibration and/or validation. Ideally, detailed speciation data on a contaminated sites would be required, together with a good characteriz

Leterme, Bertrand; Jacques, Diederik

2013-04-01

229

The effects of endosulfan and fertilizer source on soil fertility 2. Available soil nutrient levels and soil organic matter  

Microsoft Academic Search

A lab incubation study was conducted on three Quebec soils over 29 months. Soils amended with either inorganic or organic fertilizer (composted manure) were sprayed 0, 2, 4, 8 or 16 times per year with endosulfan as Thiodan (2.2 kg\\/ha). Application of the endosulfan affected extractable soil levels of Ca and P in two of the above soils, but the

P. R. Warman; G. Fairchild

1984-01-01

230

Mercury Air\\/Surface Exchange Kinetics of Background Soils of the Tahquamenon River Watershed in the Michigan Upper Peninsula  

Microsoft Academic Search

Air\\/surface exchange of mercury was investigated over background soils at five sites in the Tahquamenon River watershed in the Michigan Upper Peninsula in the summer of 1998. Measurements of Hg fluxes were performed during middayperiods using the ORNL Teflon dynamic flux chamber. Mean Hg emission fluxes were 1.4±0.3–2.4±1.0 ng m-2 hr-1 for three shaded forest sites and 7.6±1.7 ng m-2

H. Zhang; S. E. Lindberg; F. J. Marsik; G. J. Keeler

2001-01-01

231

The soil–air exchange characteristics of total gaseous mercury from a large-scale municipal landfill area  

Microsoft Academic Search

The cycle of mercury (Hg) from a gigantic landfill area (area ?2.72km2) was investigated by conducting micrometeorological measurements of its exchange rates across soil–air boundary during the spring season of 2000. Based on this field campaign, we attempted to provide various insights into the Hg exchange processes, especially with respect to the decoupling of the mixed signatures of complex source

Ki-Hyun Kim; Min-Young Kim; Gangwoong Lee

2001-01-01

232

Water-air and soil-air exchange rate of total gaseous mercury measured at background sites  

Microsoft Academic Search

In order to evaluate and understand the processes of water-air and soil-air exchanges involved at background sites, an intensive field measurement campaign has been achieved during the summer of 1995 using high-time resolution techniques (10 min) at two sites (land and water) in southern Québec (Canada). Mercury flux was measured using a dynamic flux chamber technique coupled with an automatic

Laurier Poissant; Alain Casimir

1998-01-01

233

Menopause and Blood Mercury Levels: The Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011.  

PubMed

This study aimed to evaluate the association between menopause and blood mercury concentrations in South Korean women. Women aged ?20 years who participated in the Korean National Health and Nutrition Examination Survey 2008-2011 were included in this study. Primary and secondary analyses included women aged ?20 years (n?=?1,642) and 45-55 years (i.e., perimenopausal; n?=?325), respectively. For all analyses, the mercury levels were log-transformed. The linear regression model for mercury levels was adjusted for age, body mass index, household income, menopausal status, hormone replacement therapy, use of oral contraceptives, smoking history, alcohol intake, physical activity, number of pregnancies, serum ferritin levels, and fish consumption. After adjusting for covariates, log-transformed blood mercury levels were significantly lower in women who were menopausal [?-coefficient -0.1488; 95 % confidence interval -0.2586, -0.0389; P?=?0.01) than in those who were premenopausal. A similar relationship was identified in perimenopausal women (?-coefficient -0.1753; 95 % confidence interval -0.3357, -0.015; P?=?0.03). The blood mercury concentration was lower in postmenopausal women than in premenopausal women. There was a significant positive correlation between blood mercury concentrations and both the frequency of alcohol intake and serum ferritin levels. PMID:25382663

Yuk, Jin-Sung; Lee, Jung Hun; Jeon, Jin-Dong; Kim, Tai June; Lee, Myung-Hwa; Park, Won I

2014-12-01

234

Atmospheric Deposition and Fate of Mercury in High-altitude Watersheds of the Rocky Mountains.  

NASA Astrophysics Data System (ADS)

Despite the potential for cold high-altitude ecosystems to act as sinks in the global mercury cycle, atmospheric deposition and fate of mercury have not been measured extensively at mountain sites in the Western United States. At Buffalo Pass in northwestern Colorado (the highest site in the national Mercury Deposition Network at 3234 m elevation), mercury in wet deposition was 9 ? gm-2 in 2000, comparable to many sites in the upper Midwestern United States where fish consumption advisories are widespread because of elevated levels of mercury from atmospheric deposition. Similar levels of mercury deposition were measured about 90 km east of Buffalo Pass at Loch Vale in Rocky Mountain National Park (RMNP) during 2002. Concentrations of total mercury in headwater streams in RMNP averaged 2-4 ngL-1 during spring and summer of 2001-2002. Higher concentrations were observed during snowmelt and rainfall events. Dissolved mercury was generally greater than particulate mercury in these clear mountain streams. Mercury and dissolved organic carbon peaked as soils were flushed during early snowmelt and rainy summer periods. Overall, mercury deposition was greater than mercury export, indicating accumulation in alpine/subalpine ecosystems; however, the mercury exported in streamflow may contribute substantially to mercury loading in downstream lakes and reservoirs where fish consumption advisories have increased. Methyl mercury concentrations measured in the streams in 2002 were generally near or less than detection limits, however, extreme drought conditions limited hydrologic flushing of soils and wetlands that may be sources of methyl mercury. In 2003, surface and ground water from various alpine and subalpine landscapes were sampled to determine sources and transport of total and methyl mercury. The elevated levels of mercury in atmospheric deposition indicate a need for better understanding of mercury cycling and transport in high-altitude ecosystems of Western North America.

Campbell, D. H.; Mast, M. A.; Ingersoll, G. P.; Manthorne, D. J.; Krabbenhoft, D. P.; Taylor, H. E.; Aiken, G. R.; Schuster, P. F.; Reddy, M. M.

2003-12-01

235

Phosphorus Runoff: Effect of Tillage and Soil Phosphorus Levels  

Microsoft Academic Search

The transport of AAP in surface runoff and sediments is dependent on the erosion potential and the surface Continued inputs of fertilizer and manure in excess of crop require- soil P content (Sibbensen and Sharpley, 1997). The ments have led to a build-up of soil phosphorus (P) levels and in- creased P runoff from agricultural soils. The objectives of this

I. C. Daverede; A. N. Kravchenko; R. G. Hoeft; E. D. Nafziger; D. G. Bullock; J. J. Warren; L. C. Gonzini

236

Determination of Ultratrace Levels of Mercury in SRM 2781 Domestic Sludge by Combustion RNAA  

SciTech Connect

The domestic sludge SRM 2781 was collected from Denver, Colorado, sewage disposal district 1 (DMSDD) in the early 1990s. The DMSDD calls this material 'domestic' because only light industry is present in this district. The term 'domestic' differs from an 'industrial' label by the amount of heavy industry present in the area. The determination of mercury and other toxic elements in these sludges is important to monitor the sources and pathways of environmental exposure to these materials. Analytical results for the determination of total mercury in SRM 2781, domestic sludge, by radiochemical neutron activation analysis (RNAA) are listed in Table I. These analyses were made to measure the total mercury for use in the certification process of this reference material. The control sample data agreed well with the certified values and confirm the methods, procedures, and corrections used. This RNAA combustion procedure is effective in producing high-quality analytical data at the microgram/kilogram concentration level in both the organic and inorganic matrices of these samples. The procedure has both high sensitivity and freedom from significant reagent blanks when properly performed.

Bruce R. Norman; Donald A. Becker; Richard T. Lostritto

2000-11-12

237

Mercury interferes with endogenous antioxidant levels in Yukon River subsistence-fed sled dogs  

NASA Astrophysics Data System (ADS)

Before adopting modern corn-and-grain-based western processed diets, circumpolar people had a high fat and protein subsistence diet and exhibited a low incidence of obesity, diabetes and cardiovascular disease. Some health benefits are attributable to a subsistence diet that is rich in omega-3 fatty acids and antioxidants. Pollution, both global and local, is a threat to wild foods, as it introduces contaminants into the food system. Northern indigenous people and their sled dogs are exposed to a variety of contaminants, including mercury, that accumulate in the fish and game that they consume. The sled dogs in Alaskan villages are maintained on the same subsistence foods as their human counterparts, primarily salmon, and therefore they can be used as a food systems model for researching the impact of changes in dietary components. In this study, the antioxidant status and mercury levels were measured for village sled dogs along the Yukon River. A reference kennel, maintained on a nutritionally balanced commercial diet, was also measured for comparison. Total antioxidant status was inversely correlated with the external stressor mercury.

Dunlap, Kriya L.; Reynolds, Arleigh J.; Gerlach, S. Craig; Duffy, Lawrence K.

2011-10-01

238

Mercury levels in mink (Mustela vison) and river otter (Lontra canadensis) from northeastern North America.  

PubMed

Aquatic ecosystems have received mercury released from anthropogenic sources. The northeast region of North America is at especially high risk because of local and regional emission sources, prevailing wind patterns, and certain hydrological and biogeochemical features. Here we examine regional variation in total mercury (Hg) in brain, liver, and fur from otter and mink collected across New York, New England, and Nova Scotia. Gender and age are examined as factors potentially affecting Hg tissue levels. In addition, temporal relationships are analyzed for New York as well as correlative relationships for tissues from Maine. Animals were collected from 1982 to 2003, mostly from licensed trappers. Liver was the only tissue from otter that exhibited significant regional variation (New York versus Maine) in Hg concentration. Mercury concentration was significantly related to age but not to gender for otter. All tissues in mink exhibited significant, but inconsistent, regional variation in total Hg concentration, with the highest mean Hg concentration in liver samples from Massachusetts/Connecticut. Female mink had significantly greater Hg concentrations in liver than males. Total Hg concentration in the liver of both otter and mink from New York decreased significantly with time. Correlations among tissues for Hg concentration were stronger for male and female mink and male otter than female otter from Maine. PMID:15931971

Yates, David E; Mayack, David T; Munney, Kenneth; Evers, David C; Major, Andrew; Kaur, Taranjit; Taylor, Robert J

2005-03-01

239

Applications of Organic and Inorganic Amendments Induce Changes in the Mobility of Mercury and Macro- and Micronutrients of Soils  

PubMed Central

Both soil organic matter and sulfur (S) can reduce or even suppress mercury (Hg) mobility and bioavailability in soil. A batch incubation experiment was conducted with a Chernozem and a Luvisol artificially contaminated by 440?mg·kg?1?Hg showing wide differences in their physicochemical properties and available nutrients. The individual treatments were (i) digestate from the anaerobic fermentation of biowaste; (ii) fly ash from wood chip combustion; and (iii) ammonium sulfate, and every treatment was added with the same amount of S. The mobile Hg portion in Chernozem was highly reduced by adding digestate, even after 1 day of incubation, compared to control. Meanwhile, the outcome of these treatments was a decrease of mobile Hg forms as a function of incubation time whereas the contents of magnesium (Mg), potassium (K), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), and phosphorus (P) were stimulated by the addition of digestate in both soils. The available calcium (Ca) contents were not affected by the digestate addition. The experiment proved digestate application as the efficient measure for fast reduction of mobile Hg at extremely contaminated soils. Moreover, the decrease of the mobile mercury portion was followed by improvement of the nutrient status of the soils.

Garcia-Sanchez, Mercedes; Sipkova, Adela; Szakova, Jirina; Kaplan, Lukas; Ochecova, Pavla; Tlustos, Pavel

2014-01-01

240

Response of rice to soil phosphorus levels  

E-print Network

~ ~ ~ Relationship of soil test phosphorus with the peroent yield (grain and straw) and. total up- take of phosphorus on Lake Charles oiay ~ ~ . . +, ~ 52 Vy SUMMARY ND CONCLUSIORS ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ o ~ ~ ~ o ~ ~ o ~ ~ a ~ boise 59 VIe LITERATURE CITED... the following three soil types was used during this study' (1) Rockley fine sandy loam~ a greyish brown sandy loam over a sandy olay su'bsoil. Its surface and internal d. rainsge is slow, but adequate for the growth of all common field crops, This soil...

Quddus, Mohammad Abdul

2012-06-07

241

Targeting geothermal exploration sites in the Mount St. Helens area using soil mercury surveys  

SciTech Connect

The background mercury level was determined for the areas studied, providing preliminary information for future work. Identification of areas which might merit more intensive sampling was also accomplished. The clusters of samples with high Hg concentrations in both areas may indicate high heat flow and should be investigated further. Problems involving the use of this method in the Cascades were also identified. Both areas north and south of the mountain had approximately the same standard deviation (expressed as a percentage of the mean), even though the sampling horizons seemed much more consistent and less disturbed in the Marble Mountain area than in the Green River Soda Springs area. This may indicate that for these areas, secondary controls are more important, or that Hg anomalies are much smaller than indicated in studies of other areas.

Holmes, J.; Waugh, K.

1983-11-01

242

Mercury and selenium levels in 19 species of saltwater fish from New Jersey as a function of species, size, and season.  

PubMed

There are few data on risks to biota and humans from mercury levels in saltwater fish. This paper examines mercury and selenium levels in muscle of 19 species of fish caught by recreational fisherfolk off the New Jersey shore, as a function of species of fish, size, and season, and risk of mercury to consumers. Average mercury levels ranged from 0.01 ppm (wet weight) (Menhaden Brevoortia tyrannus) to 1.83 ppm (Mako Shark Isurus oxyrinchus). There were four categories of mercury levels: very high (only Mako), high (averaging 0.3-0.5 ppm, 3 species), medium (0.14-0.20 ppm, 10 species), and low (below 0.13 ppm, 5 species). Average selenium levels for the fish species ranged from 0.18 ppm to 0.58 ppm, and had lower variability than mercury (coefficient of variation=38.3 vs 69.1%), consistent with homeostatic regulation of this essential element. The correlation between mercury and selenium was significantly positive for five and negative for two species. Mercury levels showed significant positive correlations with fish size for ten species. Size was the best predictor of mercury levels. Selenium showed no consistent relationship to fish length. Over half of the fish species had some individual fish with mercury levels over 0.3 ppm, and a third had fish with levels over 0.5 ppm, levels that pose a human health risk for high end consumers. Conversely several fish species had no individuals above 0.5 ppm, and few above 0.3 ppm, suggesting that people who eat fish frequently, can reduce their risk from mercury by selecting which species (and which size) to consume. Overall, with the exception of shark, Bluefin Tuna (Thunnus thynnus), Bluefish (Pomatomus saltatrix) and Striped Bass (Morone saxatilis), the species sampled are generally medium to low in mercury concentration. Selenium:mercury molar ratios were generally above 1:1, except for the Mako shark. PMID:21292311

Burger, Joanna; Gochfeld, Michael

2011-03-15

243

Critical levels of atmospheric pollution: criteria and concepts for operational modelling of mercury in forest and lake ecosystems.  

PubMed

Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European efforts to limit transboundary air pollution is the development of emission-exposure-effect relationships, with the aim of determining the critical level of atmospheric pollution (CLAP, cf. critical load) causing harm or concern in sensitive elements of the environment. This requires a quantification of slow ecosystem dynamics from short-term collections of data. Aiming at an operational tool for assessing the past and future metal contamination of terrestrial and aquatic ecosystems, we present a simple and flexible modelling concept, including ways of minimizing requirements for computation and data collection, focusing on the exposure of biota in forest soils and lakes to Hg. Issues related to the complexity of Hg biogeochemistry are addressed by (1) a model design that allows independent validation of each model unit with readily available data, (2) a process- and scale-independent model formulation based on concentration ratios and transfer factors without requiring loads and mass balance, and (3) an equilibration concept that accounts for relevant dynamics in ecosystems without long-term data collection or advanced calculations. Based on data accumulated in Sweden over the past decades, we present a model to determine the CLAP-Hg from standardized values of region- or site-specific synoptic concentrations in four key matrices of boreal watersheds: precipitation (atmospheric source), large lacustrine fish (aquatic receptor and vector), organic soil layers (terrestrial receptor proxy and temporary reservoir), as well as new and old lake sediments (archives of response dynamics). Key dynamics in watersheds are accounted for by quantifying current states of equilibration in both soils and lakes based on comparison of contamination factors in sediment cores. Future steady-state concentrations in soils and fish in single watersheds or entire regions are then determined by corresponding projection of survey data. A regional-scale application to southern Sweden suggests that the response of environmental Hg levels to changes in atmospheric Hg pollution is delayed by centuries and initially not proportional among receptors (atmosphere > soils not equal sediments>fish; clearwater lakes > humic lakes). This has implications for the interpretation of common survey data as well as for the implementation of pollution control strategies. Near Hg emission sources, the pollution of organic soils and clearwater lakes deserves attention. Critical receptors, however, even in remote areas, are humic waters, in which biotic Hg levels are naturally high, most likely to increase further, and at high long-term risk of exceeding the current levels of concern: soil organic matter. If environmental Hg concentrations are to be reduced and kept below these critical limits, virtually no man-made atmospheric Hg emissions can be permitted. PMID:12663174

Meili, Markus; Bishop, Kevin; Bringmark, Lage; Johansson, Kjell; Munthe, John; Sverdrup, Harald; de Vries, Wim

2003-03-20

244

A new, catchment-scale model for simulating methyl and total mercury in soils and surface waters  

NASA Astrophysics Data System (ADS)

Mercury (Hg) is a potent and persistent neurotoxin. It is subject to long-range atmospheric transport, accumulates in catchment soils, and can pose health risks to humans and animals both at the point of use as well as in remote locations. Elevated concentrations of methyl mercury (MeHg) in fish are related to atmospheric Hg deposition and have resulted in fish consumption advisories in many parts of North America and Fennoscandia. After more than 150 years of elevated Hg deposition in Europe and North America, there remains a large inventory of Hg in the terrestrial catchments of lakes, which continues to be exported to receiving waters despite decreasing atmospheric inputs. While a substantial Hg pool exists in boreal catchment soils, fluxes of Hg from catchments via stream runoff tend to be much lower than atmospheric Hg inputs. Terrestrial catchments receiving similar atmospheric Hg inputs can have markedly different patterns of Hg output in stream water. Considering the importance of catchment processes in determining Hg flux to lakes and subsequent MeHg concentrations in fish, there is a need to characterize Hg cycling and transport in boreal and temperate forest-covered catchments. We present a new, catchment-scale, process-based dynamic model for simulating Hg in soils and surface waters. The Integrated Catchments Model for Mercury (INCA-Hg) simulates transport of gaseous, dissolved and solid Hg and transformations between elemental (Hg0), ionic (Hg(II)) and MeHg in natural and semi-natural landscapes. The mathematical description represents the model as a series of linked, first-order differential equations describing chemical and hydrological processes in catchment soils and waters which control surface water Hg dynamics and subsequent fluxes to lakes and other receiving waters. The model simulates daily time series between one and one hundred years long and can be applied to catchments ranging in size from <1 to ~10000 km2. Here we present applications of the model to two boreal forest headwater catchments in central Canada where we were able to reproduce observed patterns of stream water total mercury (THg) and MeHg fluxes and concentrations. Model performance was assessed using Monte Carlo techniques. Simulated in-stream THg and MeHg concentrations were sensitive to hydrologic controls and terrestrial and aquatic process rates. Our results show the need for new research to better quantify in-situ methylation and demethylation rates in soils and surface waters and for additional surveys of soil Hg concentrations. These data are needed for constraining model simulations of the effects of changing climate, Hg deposition and land management on fluxes of THg and MeHg.

Futter, M. N.; Poste, A. E.; Whitehead, P. G.; Dillon, P. J.

2012-04-01

245

Review of State Soil Cleanup Levels for Dioxin (December 2009)  

EPA Science Inventory

This final report summarizes a survey of state soil cleanup levels for dioxin and characterizes the science underlying these values. The objective of this project was to summarize existing state cleanup levels for dioxin in soil, together with their scientific bases where availa...

246

Boron Levels in Soils Cropped to Coffee and their Relationships to some Soil Properties in Ghana  

Microsoft Academic Search

Studies on boron levels in soils cropped to coffee were carried out in Ghana due to widespread reports on boron deficiency in soils of some coffee producing countr ies. Leaves and soils were sampled from Cocobod coffee plantations at Bogoso, Suhuma, Manso-Mim, Bunso and Bepong, which represent the main coffee growing areas in the Western, Ashanti and Eastern regions of

A. A. Afrifa; K. Ofori-Frimpong; M. K. Abekoe

247

Arsenic and mercury in the soils of an industrial city in the Donets Basin, Ukraine  

USGS Publications Warehouse

Soil and house dust collected in and around Hg mines and a processing facility in Horlivka, a mid-sized city in the Donets Basin of southeastern Ukraine, have elevated As and Hg levels. Surface soils collected at a former Hg-processing facility had up to 1300 mg kg?1 As and 8800 mg kg?1 Hg; 1M HCl extractions showed 74–93% of the total As, and 1–13% of the total Hg to be solubilized, suggesting differential environmental mobility between these elements. In general, lower extractability of As and Hg was seen in soil samples up to 12 km from the Hg-processing facility, and the extractable (1M HCl, synthetic precipitation, deionized water) fractions of As are greater than those for Hg, indicating that Hg is present in a more resistant form than As. The means (standard deviation) of total As and Hg in grab samples collected from playgrounds and public spaces within 12 km of the industrial facility were 64 (±38) mg kg?1 As and 12 (±9.4) mg kg?1 Hg; all concentrations are elevated compared to regional soils. The mean concentrations of As and Hg in dust from homes in Horlivka were 5–15 times higher than dust from homes in a control city. Estimates of possible exposure to As and Hg through inadvertent soil ingestion are provided.

Conko, Kathryn M.; Landa, Edward R.; Kolker, Allan; Kozlov, Kostiantyn; Gibb, Herman J.; Centeno, Jose; Panov, Boris S.; Panov, Yuri B.

2013-01-01

248

Mercury in soil near a long-term air emission source in southeastern Idaho  

USGS Publications Warehouse

At the Idaho National Engineering and Environmental Laboratory in southeastern Idaho, a 500??C fluidized bed calciner was intermittently operated for 37 years, with measured Hg emission rates of 9-11 g/h. Surface soil was sampled at 57 locations around the facility to determine the spatial distribution of Hg fallout and surface Hg variability, and to predict the total residual Hg mass in the soil from historical emissions. Measured soil concentrations were slightly higher (p<0.05) within 5 km of the source but were overall very low (15-20 ng/g) compared to background Hg levels published for similar soils in the USA (50-70 ng/g). Concentrations decreased 4%/cm with depth and were found to be twice as high under shrubs and in depressions. Mass balance calculations accounted for only 2.5-20% of the estimated total Hg emitted over the 37-year calciner operating history. These results suggest that much of the Hg deposited from calciner operations may have been reduced in the soil and re-emitted as Hg(0) to the global atmospheric pool.

Abbott, M.L.; Susong, D.D.; Olson, M.; Krabbenhoft, D.P.

2003-01-01

249

Mercury in ground water, septage, leach-field effluent, and soils in residential areas, New Jersey coastal plain  

USGS Publications Warehouse

Water samples were collected from domestic wells at an unsewered residential area in Gloucester County, New Jersey where mercury (Hg) concentrations in well water were known to exceed the USEPA maximum contaminant level (MCL) of 2000 ng/L. This residential area (the CSL site) is representative of more than 70 such areas in southern New Jersey where about 600 domestic wells, sampled previously by State and county agencies, yielded water containing Hg at concentrations that exceed the MCL. Recent studies indicate that background concentrations of Hg in water from this unconfined sand and gravel aquifer system are < 10 ng/L. Additional sampling was conducted at the CSL site in order to better understand sources of Hg and potential Hg transport mechanisms in the areas with Hg-contaminated ground water. At the CSL site, concentrations of Hg were substantially lower (although still exceeding the MCL in some cases) in filtered water samples than in the unfiltered water samples collected previously from the same wells. Surfactants and elevated concentrations of sodium, chloride, nitrate, ammonium, and phosphate in water from domestic and observation wells indicated septic-system effects on water quality; detections of sulfide indicated localized reducing conditions. Hg concentrations in septage and leach-field effluent sampled at several other households in the region were low relative to the contaminant-level Hg concentrations in water from domestic wells. Relations of Hg concentrations in leach-field effluent to iron concentrations indicate that reductive dissolution of iron hydroxides in soils may release Hg to the percolating effluent. ?? 2005 Elsevier B.V. All rights reserved.

Barringer, J. L.; Szabo, Z.; Schneider, D.; Atkinson, W. D.; Gallagher, R. A.

2006-01-01

250

Determination of the potential for release of mercury from combustion product amended soils: Part 1 - Simulations of beneficial use  

SciTech Connect

This paper describes a project that assessed the potential for mercury (Hg) release to air and water from soil amended with combustion products to simulate beneficial use. Combustion products (ash) derived from wood, sewage sludge, subbituminous coal, and a subbituminous coal-petroleum coke mixture were added to soil as agricultural supplements, soil stabilizers, and to develop low permeability surfaces. Hg release was measured from the latter when intact and after it was broken up and mixed into the soil. Air-substrate Hg exchange was measured for all materials six times over 24 hr, providing data that reflected winter, spring, summer, and fall meteorological conditions. Dry deposition of atmospheric Hg and emission of Hg to the atmosphere were both found to be important fluxes. Measured differences in seasonal and diel (24 hr) fluxes demonstrated that to establish an annual estimate of air-substrate flux from these materials data on both of these time steps should be collected. Air-substrate exchange was highly correlated with soil and air temperature, as well as incident light. Hg releases to the atmosphere from coal and wood combustion product-amended soils to simulate an agricultural application were similar to that measured for the unamended soil, whereas releases to the air for the sludge-amended materials were higher. Hg released to soil solutions during the Synthetic Precipitation Leaching Procedure for ashamended materials was higher than that released from soil alone. On the basis of estimates of annual releases of Hg to the air from the materials used, emissions from coal and wood ash-amended soil to simulate an agricultural application could simply be re-emission of Hg deposited by wet processes from the atmosphere; however, releases from sludge-amended materials and those generated to simulate soil stabilization and disturbed low-permeability pads include Hg indigenous to the material. 37 refs., 5 figs., 4 tabs.

Mae Sexauer Gustin; Jody Ericksen; George C. Fernandez [University of Nevada-Reno, Reno, NV (United States). Department of Natural Resources and Environmental Sciences

2008-05-15

251

When are fetuses and young children most susceptible to soil metal concentrations of arsenic, lead and mercury?  

PubMed

This study was designed to analyze when, during pregnancy and early childhood, the association between soil metal concentrations of arsenic (As), lead (Pb) and mercury (Hg) and the outcome of intellectual disability (ID) is statistically significant. Using cluster analysis, we identified ten areas of land that contained a cluster of ID and areas of average risk for ID. We analyzed soil for As, Pb, and Hg and estimated the soil metal concentration at the residential sites where the woman and children lived during pregnancy and early childhood using a Bayesian Kriging model. Arsenic concentrations were associated with ID during the first trimester of pregnancy and Hg was associated with ID early in pregnancy and the first two years of childhood. The covariates that remained in the final models were also temporally associated with ID. PMID:22749212

McDermott, Suzanne; Bao, Weichao; Marjorie Aelion, C; Cai, Bo; Lawson, Andrew

2012-09-01

252

When are fetuses and young children most susceptible to soil metal concentrations of arsenic, lead and mercury?  

PubMed Central

This study was designed to analyze when, during pregnancy and early childhood, the association between soil metal concentrations of arsenic (As), lead (Pb) and mercury (Hg) and the outcome of intellectual disability (ID) is statistically significant. Using cluster analysis, we identified ten areas of land that contained a cluster of ID and areas of average risk for ID. We analyzed soil for As, Pb, and Hg and estimated the soil metal concentration at the residential sites where the woman and children lived during pregnancy and early childhood using a Bayesian Kriging model. Arsenic concentrations were associated with ID during the first trimester of pregnancy and Hg was associated with ID early in pregnancy and the first two years of childhood. The covariates that remained in the final models were also temporally associated with ID. PMID:22749212

McDermott, Suzanne; Bao, Weichao; Aelion, C. Marjorie; Cai, Bo; Lawson, Andrew

2012-01-01

253

Mercury distribution in the foliage and soil profiles of the Tibetan forest: processes and implications for regional cycling.  

PubMed

Remote forests are considered a pool of Mercury (Hg) in the global Hg cycle. However, notably few studies have investigated the fate of Hg in the Tibetan forest. In this study, fifty-two foliage samples and seven litter/soil profiles were collected throughout the Tibetan forest. The concentrations of total Hg (THg) in foliage were positively correlated with longitude and negatively correlated with altitude, indicating that the emission of Hg is expected to decrease with increasing distance from emission sources to the Tibetan forest. The deposition flux of THg in the Tibetan forest (with an air-to-forest ground flux of 9.2 ?g/m(2)/year) is ?2 times the flux in clearings, which is suggestive of enhanced Hg deposition by the forest. The depositional Hg is eventually stored in the forest soil, and the soil acts as a net 'sink' for Hg. PMID:24568793

Gong, Ping; Wang, Xiao-ping; Xue, Yong-gang; Xu, Bai-qing; Yao, Tan-dong

2014-05-01

254

Mercury storage in surface soils in a central Washington forest and estimated release during the 2001 Rex Creek Fire.  

PubMed

Recent investigations indicate that wildfires provide a significant flux of mercury (Hg) from terrestrial ecosystems to the atmosphere. However, little is known about how geographic location, climate, stand age, and tree species affect Hg accumulation prior to burning and loss during burning. Soil cores collected in sites burned during the summer 2001 Rex Creek Fire in the eastern Cascade Mountains (Washington State, USA) and in adjacent unburned control sites indicate that Hg loss from soils during the Rex Creek Fire averaged 6.7 (+/-2.5) g Hg ha(-1). This soil profile-based estimate of Hg release is higher than a previous estimate for the same fire based on airborne measurements of Hg and CO concentrations in smoke. This study has implications for global estimates of Hg storage in forests and release to the atmosphere during wildfires. PMID:18640702

Biswas, Abir; Blum, Joel D; Keeler, Gerald J

2008-10-01

255

Levels of total mercury in marine organisms from Adriatic Sea, Italy.  

PubMed

The presence of total mercury in fish, crustacean and cephalopod from Adriatic Sea, was investigated. The highest concentrations were observed in decreasing order in: Norway lobster (0.97 +/- 0.24 mg/kg; mean +/- SE), European hake (0.59 +/- 0.14 mg/kg), red mullet (0.48 +/- 0.09 mg/kg), blue whiting (0.38 +/- 0.09 mg/kg), Atlantic mackerel (0.36 +/- 0.08 mg/kg) and European flying squid (0.25 +/- 0.03 mg/kg). A significant difference (p < 0.01) was found between the levels of total mercury in Norway lobster and those detected in all other species. The 25% of all samples exceeded the maximum limit fixed by Commission Regulation (EC) No 1881/2006. The results show that fish and fishery products can exceed the maximum levels and stress the need of more information for consumers in particular for people that eat large amount of fish. PMID:19434348

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Zaccaroni, Annalisa; Olivieri, Vincenzo; Amorena, Michele

2009-08-01

256

MERGANSER- Predicting Mercury Levels in Fish and Loons in New England Lakes  

EPA Science Inventory

MERGANSER (MERcury Geo-spatial AssesmentS for the New England Region) is an empirical least squares multiple regression model using atmospheric deposition of mercury (Hg) and readily obtainable lake and watershed features to predict fish and common loon Hg (as methyl mercury) in ...

257

Projecting the Population-level Effects of Mercury on the Common Loon in the Northeast  

NASA Astrophysics Data System (ADS)

The Common Loon (Gavia immer) is a top-level predator in aquatic systems and is at risk to mercury contamination. This risk is of particular concern in the Northeast, the region of North America in which loons have the highest mean body concentration of methylmercury (MeHg). We used matrix population models to project the population-level effects of mercury on loons in four states in the Northeast (New York, Vermont, New Hampshire, and Maine) exhibiting different levels of risk to MeHg. Four categories of risk to MeHg (low, moderate, high, and extra high) were established based on MeHg levels observed in loons and associated effects observed at the individual and population levels in the field (e.g., behavior and reproductive success). We parameterized deterministic matrix population models using survival estimates from a 12-year band-resight data set and productivity estimates from a 25-year data set of nesting loon observations in NH. The juvenile loon survival rate was 0.55 (minimum) and 0.63 (maximum) (ages 1-3), and the adult loon survival rate was 0.95 (ages 4-30). The mean age at first reproduction was 7. The mean fertility was 0.26 fledgelings per individual at low to moderate risk; there were 53% fewer fledged young per individual at high to extra high risk. Productivity was weighted by risk for each state. The portion of the breeding population at high to extra high risk was 10% in NY, 15% in VT, 17% in NH, and 28% in ME. We also constructed a stochastic model in which productivity was randomly selected in each time step from the 25 estimates in the NH data set. Model results indicated a negative population growth rate for some states. There was a decreasing trend in population growth rate as the percentage of the loon population at high to extra high risk increased. The stochastic model showed that the population growth rate varied over a range of about 0.05 from year to year, and this range decreased as the percentage of the loon population at high to extra high risk increased. These results suggest that an increase in risk to mercury that effects a change in reproductive success may have a negative population-level effect on loons.

Evers, D. C.; Mitro, M. G.; Gleason, T. R.

2001-05-01

258

Successful Characterization and Remedial Contour of Highly Contaminated Mercury Soil at the Y-12 National Security Complex - 13593  

SciTech Connect

An area known as the 81-10 pad within the footprint of the Y-12 National Security Complex, suspected to be heavily contaminated with mercury, was slated for characterization in support of a Federal Facilities Agreement (FFA) milestone to be accomplished by September 30, 2012. A full remedial design report (RDR) required the soil in Exposure Unit -9 (EU-9) to be fully characterized for a number of contaminates of concern including mercury. The goal of this characterization effort was to determine what soil, if any, would need to be removed for the protection of industrial workers and impacts to the surface and ground water. Funding for this project was made available using buy-back scope under the American Recovery and Reinvestment Act (ARRA). The EU-9 soil unit involved 3 different classifications which were determined as follows: Class 1: Known to have been impacted, contamination is likely; Class 2: Suspected to have been impacted, contamination is unknown; Class 3: Area not known to have been impacted, contamination unlikely. Due to various sampling and analysis events since the 1980's, significant mercury contamination was expected under the concrete pad of an area known as 81-10. Mercury contamination outside of the boundary of this pad within the EU-9 footprint was not known and therefore an original planned estimate of 1,461 cubic meters of material were expected to be heavily contaminated with mercury requiring removal, treatment and disposal. Through the use of a highly effective nature and extent sampling and analysis design that involved a hybrid of statistically-based and judgmental sampling, the actual remedial contour requiring removal was approximately 717 cubic meters, roughly 12% of the original estimate. This characterization approach was executed in full compliance with the Record of Decision (ROD) [1] documents that were agreed upon by the U.S. Department of Energy, Environmental Protection Agency and Tennessee Department of Environment and Conservation. In addition, the RDR was completed ahead of the FFA milestone date of September 30, 2012. (authors)

White, Aaron; Rigas, Michael [U.S. Department of Energy Oak Ridge Operations, Oak Ridge, TN 37830 (United States)] [U.S. Department of Energy Oak Ridge Operations, Oak Ridge, TN 37830 (United States); Birchfield, Joseph W. III [1528 Paxton Drive Knoxville, TN 37918 (United States)] [1528 Paxton Drive Knoxville, TN 37918 (United States)

2013-07-01

259

Atmospheric mercury emissions from mine wastes and surrounding geologically enriched terrains  

USGS Publications Warehouse

Waste rock and ore associated with Hg, precious and base metal mining, and their surrounding host rocks are typically enriched in mercury relative to natural background concentrations (<0.1 ??g Hg g-1). Mercury fluxes to the atmosphere from mineralized areas can range from background rates (0-15 ng m-2 h-1) to tens of thousands of ng m-2 h-1. Mercury enriched substrate constitutes a long-term source of mercury to the global atmospheric mercury pool. Mercury emissions from substrate are influenced by light, temperature, precipitation, and substrate mercury concentration, and occur during the day and night. Light-enhanced emissions are driven by two processes: desorption of elemental mercury accumulated at the soil:air interface, and photo reduction of mercury containing phases. To determine the need for and effectiveness of regulatory controls on short-lived anthropogenic point sources the contribution of mercury from geologic non-point sources to the atmospheric mercury pool needs to be quantified. The atmospheric mercury contribution from small areas of mining disturbance with relatively high mercury concentrations are, in general, less than that from surrounding large areas of low levels of mercury enrichment. In the arid to semi-arid west-ern United States volatilization is the primary means by which mercury is released from enriched sites.

Gustin, M. S.; Coolbaugh, M. F.; Engle, M. A.; Fitzgerald, B. C.; Keislar, R. E.; Lindberg, S. E.; Nacht, D. M.; Quashnick, J.; Rytuba, J. J.; Sladek, C.; Zhang, H.; Zehner, R. E.

2003-01-01

260

Mercury contamination in the oil and gas industry  

Microsoft Academic Search

Mercury contamination of surficial soils and building structures is concern to the oil, natural gas, and utility industries. Spillage from mercury-filled manometers that measure pipeline pressures is a major source of mercury contamination. Because of its chemical characteristics, the mobility of mercury within the soil posed significant health and environmental impacts. Inorganic mercury strongly adsorbs onto fine soil particles and

W. Oberle; L. Warfield; J. Manship

1993-01-01

261

Mercury retorting of calcine waste, contaminated soils and railroad ballast at the Idaho National Egineering Laboratory  

SciTech Connect

The Idaho National Engineering Laboratory (INEL) has been involved in nuclear reactor research and development for over 40 years. One of the earliest major projects involved the development of a nuclear powered aircraft engine, a long-term venture which used mercury as a shielding medium. Over the course of several years, a significant amount of mercury was spilled along the railroad tracks where the test engines were transported and stored. In addition, experiments with volume reduction of waste through a calcine process employing mercury as a catalyst resulted in mercury contaminated calcine waste. Both the calcine and Test Area North wastes have been identified in Department of Energy Action Memorandums to be retorted, thereby separating the mercury from the various contaminated media. Lockheed Idaho Technologies Company awarded the Mercury Retort contract to ETAS Corporation and assigned Parsons Engineering Science, Inc. to manage the treatment field activities. The mercury retort process entails a mobile unit which consists of four trailer-mounted subsystems requiring electricity, propane, and a water supply. This mobile system demonstrates an effective strategy for retorting waste and generating minimal secondary waste.

Cotten, G.B.; Rothermel, J.S. [Parsons Engineering Science, Inc., Houston, TX (United States); Sherwood, J. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Heath, S.A.; Lo, T.Y.R. [ETAS Corporation (United States)

1996-02-28

262

Potential effect of land-leveling on soil fertility in a Brazilian rice soil  

Microsoft Academic Search

Land-leveling to improve water management in lowland rice (Oryza sativa L.) production is becoming common in many countries. This technique exposes subsoil by removal and deposition of surface soil from high- to low-lying areas. The potential effect of land-leveling on soil fertility was studied in samples from an alluvial soil at depths of 0- to 5-, 5- to 15-, and

Ricardo E. Preve; D. C. Martens

1990-01-01

263

Mercury in municipal solid wastes and New Jersey mercury prevention and reduction program  

SciTech Connect

Mercury is a very toxic heavy metal which accumulates in the brain causing neurological damages involving psychasthenic and vegetative syndrome. At high exposure levels it causes behavioral and personality changes, loss of memory and insomnia. Long-term exposure or exposure during pregnancy to mercury or mercury compounds can permanently damage the kidney and fetus. In addition to potential effects on human health, mercury poisoning can also affect other living organisms. Mercury is different than other heavy metals. It consistently biomagnifies and bioaccumulates within the aquatic food chain. Global sources of mercury release are both natural and anthropogenic. Natural sources include volatilization of gaseous-mercury iron soils ana rocks, volcanic releases, evaporation from the ocean and other water bodies. Anthropogenic sources are fuel and coal combustion, mining, smelting, manufacturing activities, disposal of sludge, pesticides, animal and food waste, and incineration of municipal solid waste. Worldwide combustion of municipal solid waste is the second largest source of atmospheric emission of mercury. In New Jersey, incineration of solid waste is the largest source of atmospheric emission of mercury. The New Jersey Department of Environmental Protection and Energy (NJDEPE) has developed a comprehensive program to control and prevent emission of mercury resulting from combustion municipal solid waste.

Erdogan, H.; Stevenson, E. [New Jersey Department of Environmental Protection, Trenton, NJ (United States). Division of Science and Research

1994-12-31

264

Electronic characterization of defects in narrow gap semiconductors: Comparison of electronic energy levels and formation energies in mercury cadmium telluride, mercury zinc telluride, and mercury zinc selenide  

NASA Technical Reports Server (NTRS)

The project has evolved to that of using Green's functions to predict properties of deep defects in narrow gap materials. Deep defects are now defined as originating from short range potentials and are often located near the middle of the energy gap. They are important because they affect the lifetime of charge carriers and hence the switching time of transistors. We are now moving into the arena of predicting formation energies of deep defects. This will also allow us to make predictions about the relative concentrations of the defects that could be expected at a given temperature. The narrow gap materials mercury cadmium telluride (MCT), mercury zinc telluride (MZT), and mercury zinc selenide (MZS) are of interest to NASA because they have commercial value for infrared detecting materials, and because there is a good possibility that they can be grown better in a microgravity environment. The uniform growth of these crystals on earth is difficult because of convection (caused by solute depletion just ahead of the growing interface, and also due to thermal gradients). In general it is very difficult to grow crystals with both radial and axial homogeneity.

Patterson, James D.; Li, Wei-Gang

1995-01-01

265

Can mercury in fish be reduced by water level management? Evaluating the effects of water level fluctuation on mercury accumulation in yellow perch (Perca flavescens).  

PubMed

Mercury (Hg) contamination of fisheries is a major concern for resource managers of many temperate lakes. Anthropogenic Hg contamination is largely derived from atmospheric deposition within a lake's watershed, but its incorporation into the food web is facilitated by bacterial activity in sediments. Temporal variation in Hg content of fish (young-of-year yellow perch) in the regulated lakes of the Rainy-Namakan complex (on the border of the United States and Canada) has been linked to water level (WL) fluctuations, presumably through variation in sediment inundation. As a result, Hg contamination of fish has been linked to international regulations of WL fluctuation. Here we assess the relationship between WL fluctuations and fish Hg content using a 10-year dataset covering six lakes. Within-year WL rise did not appear in strongly supported models of fish Hg, but year-to-year variation in maximum water levels (?maxWL) was positively associated with fish Hg content. This WL effect varied in magnitude among lakes: In Crane Lake, a 1 m increase in ?maxWL from the previous year was associated with a 108 ng increase in fish Hg content (per gram wet weight), while the same WL change in Kabetogama was associated with only a 5 ng increase in fish Hg content. In half the lakes sampled here, effect sizes could not be distinguished from zero. Given the persistent and wide-ranging extent of Hg contamination and the large number of regulated waterways, future research is needed to identify the conditions in which WL fluctuations influence fish Hg content. PMID:25134675

Larson, James H; Maki, Ryan P; Knights, Brent C; Gray, Brian R

2014-10-01

266

Can mercury in fish be reduced by water level management? Evaluating the effects of water level fluctuation on mercury accumulation in yellow perch (Perca flavescens)  

USGS Publications Warehouse

Mercury (Hg) contamination of fisheries is a major concern for resource managers of many temperate lakes. Anthropogenic Hg contamination is largely derived from atmospheric deposition within a lake’s watershed, but its incorporation into the food web is facilitated by bacterial activity in sediments. Temporal variation in Hg content of fish (young-of-year yellow perch) in the regulated lakes of the Rainy–Namakan complex (on the border of the United States and Canada) has been linked to water level (WL) fluctuations, presumably through variation in sediment inundation. As a result, Hg contamination of fish has been linked to international regulations of WL fluctuation. Here we assess the relationship between WL fluctuations and fish Hg content using a 10-year dataset covering six lakes. Within-year WL rise did not appear in strongly supported models of fish Hg, but year-to-year variation in maximum water levels (?maxWL) was positively associated with fish Hg content. This WL effect varied in magnitude among lakes: In Crane Lake, a 1 m increase in ?maxWL from the previous year was associated with a 108 ng increase in fish Hg content (per gram wet weight), while the same WL change in Kabetogama was associated with only a 5 ng increase in fish Hg content. In half the lakes sampled here, effect sizes could not be distinguished from zero. Given the persistent and wide-ranging extent of Hg contamination and the large number of regulated waterways, future research is needed to identify the conditions in which WL fluctuations influence fish Hg content.

Larson, James H.; Maki, Ryan P.; Knights, Brent C.; Gray, Brian R.

2014-01-01

267

Overview of investigations into mercury in ground water, soils, and septage, New Jersey coastal plain  

USGS Publications Warehouse

Since the early 1980s, investigations by health departments of eight counties in southern New Jersey, by the NJ Department of Environmental Protection (NJDEP), and subsequently by the US Geological Survey (USGS), have shown that Hg concentrations in water tapped by about 600 domestic wells exceed the maximum contaminant level (MCL) of 2 ??g/L. The wells are finished in the areally extensive unconfined Kirkwood-Cohansey aquifer system of New Jersey's Coastal Plain; background concentrations of Hg in water from this system are < 0.01 ??g/L. Evidence of contributions from point sources of Hg, such as landfills or commercial and industrial hazardous-waste sites, is lacking. During 1996-2003, the USGS collected water samples from 203 domestic, irrigation, observation, and production wells using ultraclean techniques; septage, leach-field effluent, soils, and aquifer sediments also were sampled. Elevated concentrations of NH4, B, Cl, NO3, and Na and presence of surfactants in domestic-well water indicate that septic-system effluent can affect water quality in unsewered residential areas, but neither septage nor effluent appears to be a major Hg source. Detections of hydrogen sulfide in ground water at a residential area indicate localized reducing conditions; undetectable SO4 concentrations in water from other residential areas indicate that reducing conditions, which could be conducive to Hg methylation, may be common locally. Volatile organic compounds (VOCs), mostly chlorinated solvents, also are found in ground water at the affected areas, but statistically significant associations between presence of Hg and VOCs were absent for most areas evaluated. Hg concentrations are lower in some filtered water samples than in paired unfiltered samples, likely indicating that some Hg is associated with particles or colloids. The source of colloids may be soils, which, when undisturbed, contain higher concentrations of Hg than do disturbed soils and aquifer sediments. Soil disturbance during residential development and inputs from septic systems are hypothesized to mobilize Hg from soils to ground water. ?? Springer 2006.

Barringer, J.L.; Szabo, Z.

2006-01-01

268

Check on level of environmental contamination by mercury and cleanup of Abetina Mining area (Grosseto-Italia)  

SciTech Connect

The purpose of the study was to check on the level of environmental contamination and to design a project for cleaning up the Abetina Mine area at Piancastagnaio (Grosseto, Italy). Contamination of this area had occurred during the mining and treatment of cinnabar (HgS) over a prolonged period. The aim of the project is to remove the sources of contamination or render them harmless. Mining of the Piancastagnaio deposit started in 1840, mercury metal being extracted from the ore by thermal treatment. Together with Spain, Italy was the first country to produce this metal and was the world leader in this field between 1936 and 1943. Though mercury production in the Monte Amiata region of Tuscany ceased in 1974 the ensuing environmental impact is very evident, taking the form of rusty old mining and processing works, plus waste tips which still contain considerable amount of mercury even after the ore had been subject to thermal extraction treatment. The research which has been conducted included mapping the area to identify the main sources of mercury and arsenic pollution, as well as the level of environmental contamination. Mercury and arsenic values in excess of 16,000 and 150 ppm respectively are encountered in the most highly-contaminated places. 11 refs., 6 figs., 2 tabs.

Belardi, G.; Marabini, A.M.; Passariello, B. [Institute for Minerals Treatment, Rome (Italy)] [and others

1996-12-31

269

Mercury, arsenic and selenium exposure levels in relation to fish consumption in the Mediterranean area.  

PubMed

In order to assess mercury (Hg), selenium (Se) and arsenic (As) exposure in the Mediterranean area, total mercury (THg), monomethylmercury (MeHg), Se and As levels were measured in umbilical cord blood and breast milk from Italian (n=900), Slovenian (n=584), Croatian (n=234) and Greek (n=484) women. THg, MeHg, As, and Se levels were also determined in blood samples of the same mothers from Italy and Croatia. In addition, THg and MeHg were determined in the same women's hair from all the countries involved in this study and As and Se levels were determined in the mother's urine samples from Italy, Croatia and Greece. Besides recording the consumption of other food items, the frequencies of fish consumption were assessed by detailed food frequency questionnaires, since fish represents an important source of Hg, Se and As in humans. The highest levels of THg and As were found in cord blood (Med((THg))=5.8 ng/g; Med((As))=3.3 ng/g) and breast milk (Med((THg))=0.6 ng/g; Med((As))=0.8 ng/g) from Greek women, while the highest Se levels were found in cord blood (Med=113 ng/g) from Italy. Significant linear correlations were found between Hg, Se and As in blood, cord blood and breast milk. In addition, significant relations were found between the frequencies of total fish consumption and biomarkers of As, MeHg and Se exposure, with the strongest Spearman rank coefficients between frequencies of total fish consumption and THg levels in cord blood (r(s)=0.442, p<0.001) or THg levels in hair (r(s)=0.421, p<0.001), and between frequencies of total fish consumption and As levels in cord blood (r(s)=0.350, p<0.001). The differences in Hg and As exposure between countries were probably due to different amounts of fish consumption and the consumption of different species of fish of different origin, while the highest Se levels in women from Italy were probably the consequence of the more frequent consumption of different non specific food items. Moreover, fish consumption, the possible common source of As, Hg and Se intake, could explain the correlations between the elements determined in cord blood, mother's blood or breast milk. PMID:22999706

Miklav?i?, Ana; Casetta, Anica; Snoj Tratnik, Janja; Mazej, Darja; Krsnik, Mladen; Mariuz, Marika; Sofianou, Katia; Spiri?, Zdravko; Barbone, Fabio; Horvat, Milena

2013-01-01

270

Perchlorate levels in soil and waters from the Atacama Desert.  

PubMed

Perchlorate is an anion that originates as a contaminant in ground and surface waters. The presence of perchlorate in soil and water samples from northern Chile (Atacama Desert) was investigated by ion chromatography-electrospray mass spectrometry. Results indicated that perchlorate was found in five of seven soils (cultivated and uncultivated) ranging from 290 ± 1 to 2,565 ± 2 ?g/kg. The greatest concentration of perchlorate was detected in Humberstone soil (2,565 ± 2 ?g/kg) associated with nitrate deposits. Perchlorate levels in Chilean soils are greater than those reported for uncultivated soils in the United States. Perchlorate was also found in superficial running water ranging from 744 ± 0.01 to 1,480 ± 0.02 ?g/L. Perchlorate water concentration is 30-60 times greater than levels established by the United States Environmental Protection Agency (24.5 ?g/L) for drinking. PMID:24165784

Calderón, R; Palma, P; Parker, D; Molina, M; Godoy, F A; Escudey, M

2014-02-01

271

Seasonal, locational and size variations in mercury and selenium levels in striped bass (Morone saxatilis) from New Jersey  

PubMed Central

We examined total mercury and selenium levels in muscle of striped bass (Morone saxatilis) collected from 2005 to 2008 from coastal New Jersey. Of primary interest was whether there were differences in mercury and selenium levels as a function of size and location, and whether the legal size limits increased the exposure of bass consumers to mercury. We obtained samples mainly from recreational anglers, but also by seine and trawl. For the entire sample (n = 178 individual fish), the mean (± standard error) for total mercury was 0.39 ± 0.02 ?g/g (= 0.39 ppm, wet weight basis) with a maximum of 1.3 ?g/g (= 1.3 ppm wet weight). Mean selenium level was 0.30 ± 0.01 ?g/g (w/w) with a maximum of 0.9 ?g/g). Angler-caught fish (n = 122) were constrained by legal size limits to exceed 61 cm (24 in.) and averaged 72.6 ± 1.3 cm long; total mercury averaged 0.48 ± 0.021 ?g/g and selenium averaged 0.29 ± 0.01 ?g/g. For comparable sizes, angler-caught fish had significantly higher mercury levels (0.3 vs 0.21 ?g/g) than trawled fish. In both the total and angler-only samples, mercury was strongly correlated with length (Kendall tau = 0.37; p < 0.0001) and weight (0.38; p < 0.0001), but was not correlated with condition or with selenium. In the whole sample and all subsamples, total length yielded the highest r2 (up to 0.42) of any variable for both mercury and selenium concentrations. Trawled fish from Long Branch in August and Sandy Hook in October were the same size (68.9 vs 70.1 cm) and had the same mercury concentrations (0.22 vs 0.21 ppm), but different selenium levels (0.11 vs 0.28 ppm). The seined fish (all from Delaware Bay) had the same mercury concentration as the trawled fish from the Atlantic coast despite being smaller. Angler-caught fish from the North (Sandy Hook) were larger but had significantly lower mercury than fish from the South (mainly Cape May). Selenium levels were high in small fish, low in medium-sized fish, and increased again in larger fish, but overall selenium was correlated with length (tau = 0.14; p = 0.006) and weight (tau = 0.27; p < 0.0001). Length-squared contributed significantly to selenium models, reflecting the non-linear relationship. Inter-year differences were explained partly by differences in sizes. The selenium:mercury molar ratio was below 1:1 in 20% of the fish and 25% of the angler-caught fish. Frequent consumption of large striped bass can result in exposure above the EPA’s reference dose, a problem particularly for fetal development. PMID:22226733

Gochfeld, Michael; Burger, Joanna; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

2014-01-01

272

Mercury levels in raccoons (Procyon lotor) from the Warta Mouth National Park, northwestern Poland.  

PubMed

This is the first report on mercury (Hg) levels in the liver, kidney, skeletal muscle, and brain of raccoon in Europe. It studied Hg concentration in 24 raccoons from the Warta Mouth National Park, northwestern Poland by atomic absorption spectroscopy (AAS). The highest total Hg concentrations in the raccoon were found in the liver (maximum, 18.45 mg/kg dry weight), while the lowest in the brain (maximum, 0.49 mg/kg dw). In adult raccoons, Hg concentrations in the liver, kidney, and brain were higher than in immature individuals (p<0.001), while similar in skeletal muscle in both age groups. Our results are consistent with studies by other authors conducted in North America in areas with similar environmental conditions. PMID:24736978

Lanocha, Natalia; Kalisinska, Elzbieta; Kosik-Bogacka, Danuta I; Budis, Halina; Podlasinska, Joanna; Jedrzejewska, Ewa

2014-06-01

273

Glutathione enzyme and selenoprotein polymorphisms associate with mercury biomarker levels in Michigan dental professionals  

Microsoft Academic Search

Mercury is a potent toxicant of concern to both the general public and occupationally exposed workers (e.g., dentists). Recent studies suggest that several genes mediating the toxicokinetics of mercury are polymorphic in humans and may influence inter-individual variability in mercury accumulation. This work hypothesizes that polymorphisms in key glutathione synthesizing enzyme, glutathione s-transferase, and selenoprotein genes underlie inter-individual differences in

Jaclyn M. Goodrich; Yi Wang; Brenda Gillespie; Robert Werner; Alfred Franzblau; Niladri Basu

274

Using native epiphytic ferns to estimate the atmospheric mercury levels in a small-scale gold mining area of West Java, Indonesia.  

PubMed

Mercury pollution is caused by artisanal and small-scale gold mining (ASGM) operations along the Cikaniki River (West Java, Indonesia). The atmosphere is one of the primary media through which mercury can disperse. In this study, atmospheric mercury levels are estimated using the native epiphytic fern Asplenium nidus complex (A. nidus) as a biomonitor; these estimates shed light on the atmospheric dispersion of mercury released during mining. Samples were collected from 8 sites along the Cikaniki Basin during September-November, 2008 and September-November, 2009. The A. nidus fronds that were attached to tree trunks 1-3m above the ground were collected and measured for total mercury concentration using cold vapor atomic absorption spectrometry (CVAAS) after acid-digestion. The atmospheric mercury was collected using porous gold collectors, and the concentrations were determined using double-amalgam CVAAS. The highest atmospheric mercury concentration, 1.8 × 10(3) ± 1.6 × 10(3) ngm(-3), was observed at the mining hot spot, and the lowest concentration of mercury, 5.6 ± 2.0 ngm(-3), was observed at the remote site from the Cikaniki River in 2009. The mercury concentrations in A. nidus were higher at the mining village (5.4 × 10(3) ± 1.6 × 10(3) ngg(-1)) than at the remote site (70 ± 30 ngg(-1)). The distribution of mercury in A. nidus was similar to that in the atmosphere; a significant correlation was observed between the mercury concentrations in the air and in A. nidus (r=0.895, P<0.001, n=14). The mercury levels in the atmosphere can be estimated from the mercury concentration in A. nidus using a regression equation: log (Hg(A.nidu)/ngg(-1))=0.740 log (Hg(Air)/ngm (-3)) - 1.324. PMID:22595529

Kono, Yuriko; Rahajoe, Joeni S; Hidayati, Nuril; Kodamatani, Hitoshi; Tomiyasu, Takashi

2012-09-01

275

Mercury in municipal solid waste in China and its control: a review.  

PubMed

Although a potentially significant and preventable source of environmental pollution, mercury in municipal solid waste (MSW) has not received adequate attention in China. Discarded mercury-containing products, if not recycled, ultimately release mercury to air, soil, and groundwater, even after being properly collected and disposed of in MSW management facilities. This review presents an overview on mercury in MSW and describes the emissions associated with landfilling, incineration, and composting in China. Besides end-of-pipe technologies for controlling mercury emissions from MSW management, strategies for controlling mercury in MSW are also discussed, focusing on mercury source reduction and recycling. Batteries and fluorescent lamps contribute to approximately three-quarters of mercury in MSW, and are expected to remain as significant sources of mercury in the near future. Reducing or eliminating the mercury contents in household products, particularly batteries and fluorescent lamps, should be the top priority in controlling mercury in MSW, while it is also important to set mercury contents in consumer products at acceptable and achievable levels based on a life-cycle approach. Meanwhile, cost-effective recycling programs should be developed targeting products containing elemental mercury, such as medical thermometers and sphygmomanometers, and waste products with high mercury contents (e.g., button cells) as well. PMID:22136661

Cheng, Hefa; Hu, Yuanan

2012-01-17

276

Graphite-furnace atomic absorption method for trace-level determination of total mercury  

SciTech Connect

A method is described to determine mercury in water and urine that employs a carbon-furnace atomizer atomic absorption technique. Findings show that a matrix of 5% nitric acid (HNO/sub 3/) and 0.1% potassium dichromate (K/sub 2/Cr/sub 2/O/sub 7/) stabilize the mercury, allowing a pyrolyzation temperature of up to 300/sup 0/C. In this procedure the mercury is atomized before most of the matrix, thereby minimizing potential interferences. The applicability of this method for the determination of organic mercurials is investigated.

Keller, B.J.; Peden, M.E.; Rattonetti, A.

1984-12-01

277

High levels of mercury in biota of a new Prairie irrigation reservoir with a simplified food web in Southern Alberta, Canada  

Microsoft Academic Search

This study examined mercury levels in northern pike (Esox lucius) from the Twin Valley Reservoir in southern Alberta, 2 years after construction in 2003. The hypothesis was tested that mercury\\u000a concentrations in pike from the reservoir are significantly higher than in pike from the nearby Oldman River. Mercury concentrations\\u000a in muscle tissue (0.37–1.54 ppm) generally exceeded the consumption guideline of 0.5 ppm total

Lars BrinkmannJoseph; Joseph B. Rasmussen

2010-01-01

278

Recent changes in levels of persistent organochlorines and mercury in eggs of seabirds from the Barents Sea  

Microsoft Academic Search

Eggs of ten seabird species were collected from six regions in North Norway, Svalbard and NW Russia in 1993, and were analyzed for organochlorines (OCs) and mercury. Significant declines in levels of PCBs, p,p?-DDE, HCB, ?-HCH, ?-HCH and oxychlordane were documented in nearly half the data set since a similar study in 1983 in six of the seabird species breeding

R. T. Barrett; J. U. Skaare; G. W. Gabrielsen

1996-01-01

279

Behavior of mercury in bio-systems. II. Depuration of /sup 203/Hg/sup 2 +/ in various trophic levels  

SciTech Connect

Using radiotracer techniques, the depuration rates for methylmercury at three trophic levels in an aquatic ecosystem are examined. Bacteria (decomposers), mosquito larvae (primary consumers), and fish (secondary consumers) were studied. Results indicated that depuration rates for mercury were temperature dependent - the rate of depuration increased with increase in temperature (up to 45/sup 0/C)

Hamdy, M.K.; Prabhu, N.V.

1984-01-01

280

POPULATION-LEVEL RESPONSE OF THE COMMON LOON TO MERCURY IN TWO CANADIAN PROVINCES: A MATRIX MODELING APPROACH  

EPA Science Inventory

We used data collected from Common Loon Gavia immer populations in two Canadian provinces to demonstrate a matrix population modeling approach for evaluating population-level responses to stressors and to understand how these populations may have responded to mercury contaminatio...

281

Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield  

USGS Publications Warehouse

The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO3--N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman ?? = 0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r = 0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r2 = 0.73, with an overall 10??ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem. ?? 2009 Elsevier B.V.

Gabriel, M. C.; Kolka, R.; Wickman, T.; Nater, E.; Woodruff, L.

2009-01-01

282

Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield.  

PubMed

The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO(3)(-)-N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman rho=0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r=0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r(2)=0.73, with an overall 10 ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem. PMID:19349066

Gabriel, Mark C; Kolka, Randy; Wickman, Trent; Nater, Ed; Woodruff, Laurel

2009-06-15

283

A modified EK method with an I-/I2 lixiviant assisted and approaching cathodes to remedy mercury contaminated field soils  

NASA Astrophysics Data System (ADS)

Wanshan mercury mine is the largest cinnabar deposit in Guizhou, China. Few effective methods had been achieved to remedy Hg heavily contaminated field soils. In this paper, a modified EK method with approaching cathodes (AC-EK) and an I-/I2 lixiviant was described to remedy mercury-contaminated field soils near Wanshan mercury mine. Paddy Soil I and Paddy Soil II were sampled and contained 576.73 ± 45.50 and 491.35 ± 4.73 mg/kg Hg, respectively. Although they contained 6.9 and 9.4% organic matter respectively, more than 92 and 89% Hg were removed by AC-EK within 5 days. Removal ratio increased by 0.21 and 0.68 times using EK process with ACs over that with one single cathode (SC-EK). AC-EK method saved nearly 26.4-28.1% electric power as compared to SC-EK method. As an I-/I2 lixiviant solution was used to solubilize HgS(HgO) during EK process, the bonding of Hg to organic functional S groups should be less important than the binding to inner sites of organic matter in soil. The relationship between EK remediation effect and soil organic matter content was fitted to a linear model. It turned out that when soil OM increased by 1.0%, EK removal ratio (%) of Hg would decrease by 2.63%.

Shen, Zhemin; Zhang, Jianda; Qu, Liya; Dong, Zeqin; Zheng, Shenshen; Wang, Wenhua

2009-05-01

284

Relating land cover characteristics and common loon mercury levels using geographic information systems.  

PubMed

This effort models the relationship between mercury (Hg) levels in the common loon (Gavia immer) and land cover types as defined by the National Land Cover Database (NLCD). We constructed the model within the framework of a GIS to analyze the spatial relationships between land cover types and blood Hg levels in male common loons. Thiessan polygons were used to generate the territory for each loon. We created 150, 300, and 600-m buffers around the Thiessan polygons and modeled the relationships that existed in each distance class. Within the 150-m buffer, three cover types, crop land, shrub land, and wetland were significantly related to blood Hg levels (r2 = 0.552, p < 0.001), which may indicate that the proximity of these cover types influences Hg availability in loon territories. Cropland exhibited a negative relationship with blood Hg levels and may play a role in reducing the amount of available Hg within the study area while wetlands and shrub lands exhibit a positive relationship. The study area consisted of five major lakes and eleven smaller ponds in northwest Maine, and data included a total of 61 male common loon blood Hg samples. PMID:15931970

Kramar, David; Goodale, Wing M; Kennedy, L M; Carstensen, L W; Kaur, Taranjit

2005-03-01

285

Acute effects of mercuric chloride on intracellular GSH levels and mercury distribution in the fish Oreochromic aureus  

SciTech Connect

In recent years there has been much interest in the effects of trace metals on intracellular levels of reduced glutathione (GSH). Most of the research has been performed on rats. As GSH is ubiquitous in living organisms it is of interest to establish a relationship between mercury intoxication and intracellular GSH levels in fish; especially as fish living in rivers and coastal areas are often expose to mercury as an aquatic pollutant. The role of GSH in fish trace metal toxicity has not been thoroughly investigated. The distribution of total glutathione (oxidized + reduced) in selected black sea bass organs seems to follow the established pattern for mammalian organs. Thus, it would appear that teleostian and mammalian glutathione metabolism may have many similarities. There are few reports concerning the effects of mercury during the first few hours of exposure. The aim of this investigation is to establish any changes in organ GSH and mercury levels following just 2 h exposure to mercuric chloride (HgCl/sub 2/).

Allen, P.; Min, S.Y.; Keong, W.M.

1988-02-01

286

Mercury Levels in Mink ( Mustela vison ) and River Otter ( Lontra canadensis ) from Northeastern North America  

Microsoft Academic Search

Aquatic ecosystems have received mercury released from anthropogenic sources. The northeast region of North America is at especially high risk because of local and regional emission sources, prevailing wind patterns, and certain hydrological and biogeochemical features. Here we examine regional variation in total mercury (Hg) in brain, liver, and fur from otter and mink collected across New York, New England,

David E. Yates; David T. Mayack; Kenneth Munney; David C. Evers; Andrew Major; Taranjit Kaur; Robert J. Taylor

2005-01-01

287

Relationship between blood mercury levels and components of male song in Nelson's sparrows (Ammodramus nelsoni).  

PubMed

Mercury (Hg) adversely affects the health and behavior of exposed wildlife; however, behavioral effects remain largely unknown. Changes in avian singing behavior may affect a male's fitness because song reveals male quality and thus influences female mate choice and male territory-holding ability. Nelson's sparrows (Ammodramus nelsoni) live exclusively on salt marshes and risk high levels of Hg exposure and bioaccumulation. We recorded songs of male Nelson's sparrows at two locations with different Hg exposure to determine if total blood Hg concentration was related to song characteristics, as previously reported for other species. Males with higher blood Hg levels sang at higher maximum tonal frequency, but blood Hg and site location did not influence low tonal frequency and bout duration, contrary to predictions based on other species. Within the contaminated site, Hg levels were related to bouts per minute and gap duration, such that males at that site sang faster songs. Hg influences hormones and alters brain development, raising questions about specific effects on the brains and singing behavior of male Nelson's sparrows. PMID:22945769

McKay, Jennifer L; Maher, Christine R

2012-11-01

288

SMOS CATDS Level 3 products, Soil Moisture and Brightness Temperature  

NASA Astrophysics Data System (ADS)

The ESA's (European Space Agency) SMOS (Soil Moisture and Ocean Salinity) mission, operating since november 2009, is the first satellite dedicated to measuring the surface soil moisture and the ocean salinity. The CNES (Centre National d'Etudes Spatiales) has developed the CATDS (Centre Aval de Traitement des Données SMOS) ground segment. The CATDS provides temporal synthesis products (referred to as level 3) of soil moisture, which are now covering the whole SMOS period, i.e. since January 2010. These products have different time resolutions: daily products, 3-day global products (insuring a complete coverage of the Earth surface), 10-day composite products, and monthly averaged products. Moreover, a new product provides brightness temperatures at H and V polarizations which are computed at fixed incidence angles every 5 degrees. As the instrument measures L-band brightness temperatures at the antenna frame (X/Y polarizations), a rotation is applied to transform the observations to V/H polarizations. All the CATDS products are presented in the NetCDF format and on the EASE grid (Equal Area Scalable Earth grid) with a spatial resolution of ~ 25*25 km2 The soil moisture level 3 algorithm is based on ESA's (European Space Agency) level 2 retrieval scheme with the improvement of using several overpasses (3 at most) over a 7-day window. The use of many revisits is expected to improve the retrieved soil moisture. This communication aims at presenting the soil moisture and brightness temperature products from the CATDS as well as the other geophysical parameters retrieved, such as the vegetation optical depth or the dielectric constant of the surface. SMOS Level 3 soil moisture. 3-days aggregation product, the best estimation of soil moisture is chosen.

Berthon, L.; Mialon, A.; Al Bitar, A.; Cabot, F.; Kerr, Y. H.

2012-12-01

289

Mercury availability by operationally defined fractionation in granulometric distributions of soils and mine wastes from an abandoned cinnabar mine.  

PubMed

Mercury contamination from historic cinnabar mines represents a potential risk to the environment. Asturias, in Northern Spain, was one of the largest metallurgic and mining producer areas of Hg in Europe during the 20th century until the end of activities in 1974. Mining operations have caused Hg release and dispersion throughout the area. In this study, soils collected from calcine piles and surrounding soils at an abandoned Hg mine and metallurgical plant in Mieres (Asturias, Spain) were distributed in different particle-size subsamples. Fractionation of Hg was performed by means of a Hg-specific sequential extraction procedure complemented with the selective determination of organic Hg fraction by a specific extraction method. Extremely high concentrations of total Hg were found in calcine piles. Concentrations and mobility of Hg decreased markedly with the distance in soils located 25 m both above and below the chimney of the metallurgical plant. The sequential extraction results indicated that Hg is primarily found as elemental Hg followed by sulfide Hg in the finest subsamples. However, this distribution is inverted in the coarser grain fractions where sulfide Hg prevails. Calcine piles exhibited exceptionally high values of mobile Hg (up to 5350 ?g g(-1) in the finest subsample). Accumulation of Hg in the elemental Hg fraction was observed at decreasing grain size which is indicative of deposition of Hg vapors from the metallurgical plant. Enrichment of sulfide Hg was found in the finest subsamples of soils sampled below the chimney (up to 99 ?g g(-1)). Significant organic Hg contents were observed in the soil samples (up to 2.8 ?g g(-1)), higher than those found in other abandoned Hg mining sites. A strong correlation was observed between organic Hg and Hg humic and fulvic complexes, as well as with the elemental Hg fraction. This indicates that both humic and fulvic material and elemental Hg must be the primary variables controlling Hg methylation in these soils. PMID:24664209

Fernández-Martínez, R; Loredo, J; Ordóńez, A; Rucandio, I

2014-05-01

290

A coupled monitoring network to conduct an assessment of mercury transformation and mobilization in floodplain soils: South River, Virginia  

NASA Astrophysics Data System (ADS)

Mercury (Hg) was used between 1929 and 1950 by the DuPont plant in the production of rayon acetate fiber in Waynesboro, Virginia and released into the South River. The contamination of Hg was discovered in the 1970s and remained elevated in water, soil, sediments, and biota. The primary goal of this study is to investigate the processes that govern biogeochemical transformation and mobilization of Hg in floodplain soils at South River Mile 3.5, characterize geochemical gradients in soils and how they change over time, and to enable targeted sampling at Hg loading hot spots. The biogeochemical data will play a supporting role and be used to further develop our understanding of the processes controlling the leaching of Hg and our conceptual model. Our over-arching hypothesis is to test if leaching of bank soils is a significant source of dissolved or colloidal inorganic Hg. This effort requires an interdisciplinary geochemical approach and sensor technology to understand the interactions between floodplain soil, groundwater, and river. Our investigation will include 10 months' worth data from a number of state-of-the-art in-situ monitoring sensors, such as custom-designed redox probes, soil moisture, temperature, pressure, and conductivity installed at the site. Our preliminary results showed that the concentration of total Hg in soils was up to 900 mg/kg (wet weight).There is a significant redox gradient across the floodplain soil profile. Within the top 40 -70 cm, major changes in redox conditions from oxidizing (Eh ?+600 mV) to very reducing (Eh ?-300 mV) corresponded to heavy rainfall and overbank flooding events. High variations in stream stage may govern the surface water - groundwater exchange facilitating the downward or upward movement of the capillary fringe and saturated zone through the soil horizons, affecting soil redox potential, stability of Hg-bearing minerals and leaching of inorganic Hg into dissolved and colloidal phases. These phases may be directly transported to the South River or methylated within the saturated zone of the bank and subsequently released.

Lazareva, O.; Sparks, D. L.; Landis, R.; Ptacek, C. J.; Hicks, S.; Montgomery, D.

2013-12-01

291

Development and test application of a screening-level mercury fate model and tool for evaluating wildlife exposure risk for surface waters with mercury-contaminated sediments (SERAFM)  

Microsoft Academic Search

Complex chemical cycling of mercury in aquatic ecosystems means that tracing the linkage between anthropogenic and natural loadings of mercury to watersheds and water bodies and associated concentrations in the environment are difficult to establish without the assistance of numerical models that describe biogeochemical controls on mercury distribution and availability to organisms. This paper presents an overview of a process-based,

Christopher D. Knightes

2008-01-01

292

Hair mercury and urinary cadmium levels in Belgian children and their mothers within the framework of the COPHES/DEMOCOPHES projects.  

PubMed

A harmonized human biomonitoring pilot study was set up within the frame of the European projects DEMOCOPHES and COPHES. In 17 European countries, biomarkers of some environmental pollutants, including urinary cadmium and hair mercury, were measured in children and their mothers in order to obtain European-wide comparison values on these chemicals. The Belgian participant population consisted in 129 school children (6-11 years) and their mothers (? 45 years) living in urban or rural areas of Belgium. The geometric mean levels for mercury in hair were 0.383 ?g/g and 0.204 ?g/g for respectively mothers and children. Cadmium in mother's and children's urine was detected at a geometric mean concentration of respectively 0.21 and 0.04 ?g/l. For both biomarkers, levels measured in the mothers and their child were correlated. While the urinary cadmium levels increased with age, no trend was found for hair mercury content, except the fact that mothers hold higher levels than children. The hair mercury content increased significantly with the number of dental amalgam fillings, explaining partially the higher levels in the mothers by their higher presence rate of these amalgams compared to children. Fish or seafood consumption was the other main parameter determining the mercury levels in hair. No relationship was found between smoking status and cadmium or mercury levels, but the studied population included very few smokers. Urinary cadmium levels were higher in both mothers and children living in urban areas, while for mercury this difference was only significant for children. Our small population showed urinary cadmium and hair mercury levels lower than the health based guidelines suggested by the WHO or the JECFA (Joint FAO/WHO Expert Committee on Food Additives). Only 1% had cadmium level slightly higher than the German HBM-I value (1 ?g/l for adults), and 9% exceeded the 1 ?g mercury/g hair suggested by the US EPA. PMID:24333995

Pirard, Catherine; Koppen, Gudrun; De Cremer, Koen; Van Overmeire, Ilse; Govarts, Eva; Dewolf, Marie-Christine; Van De Mieroop, Els; Aerts, Dominique; Biot, Pierre; Casteleyn, Ludwine; Kolossa-Gehring, Marike; Schwedler, Gerda; Angerer, Jürgen; Koch, Holger M; Schindler, Birgit K; Castańo, Argelia; Esteban, Marta; Schoeters, Greet; Den Hond, Elly; Sepai, Ovnair; Exley, Karen; Horvat, Milena; Bloemen, Louis; Knudsen, Lisbeth E; Joas, Reinhard; Joas, Anke; Van Loco, Joris; Charlier, Corinne

2014-02-15

293

Sensitivity of Soil Carbon Stock Estimates in Alaska to Soil Taxonomic Level  

NASA Astrophysics Data System (ADS)

Soil carbon stock estimates will help calibrate models of soil carbon change, including fluxes of carbon between the land and the atmosphere. Warming in Alaska in the last several decades has been more rapid than global averages, and is leading to a variety of ecological changes. In particular, increased respiration of soil carbon may lead to a positive feedback for climate change by releasing carbon dioxide and methane from the land to the atmosphere. Better estimates of carbon stocks are needed to more accurately model fluxes of greenhouse gases between the land and the atmosphere. New estimates of the stocks of soil organic carbon in Alaska were made by linking spatial and field data developed by the U.S. Department of Agriculture Natural Resources Conservation Service. The spatial data are from the State Soil Geographic (STATSGO) database, and the field data are from the Soil Characterization Database, also known as the pedon database. Many more sampled pedons are available now than when the original STATSGO data were compiled. Analysis of the STATSGO data alone, as distributed in 1994, provides a soil carbon stock estimate for Alaska of less than 20 petagrams. The new estimates range from 35 to 50 petagrams of soil organic carbon for Alaska, depending on the choice of methods for linking the spatial and pedon data. The higher estimates are based on linking at more generalized taxonomic levels such as soil order or suborder. The lower estimates are based on linking at more detailed soil taxonomic levels, and are likely more precise for the areas that match, but have larger areas with no match between the pedon and spatial databases. The carbon estimates are summarized by soil taxonomic unit, by regions with similar geomorphic processes, by elevation, and by land cover type.

Bliss, N. B.; Maursetter, J.

2006-12-01

294

Tolerance of soil flagellates to increased NaCl levels.  

PubMed

The ability of heterotrophic flagellates to survive and adapt to increasing salinities was investigated in this study. Whole soil samples were subjected to salinities corresponding to marine conditions and clonal cultures were used to perform growth and adaptation experiments at a wide range of different salinities (0-50 ppm). More morphotypes tolerant to elevated NaCl levels were found in road verge soil that was heavily exposed to de-icing salt than in less exposed soils, though there were fewer tolerant than intolerant morphotypes in all soils examined. Heterotrophic flagellates isolated on a freshwater medium from a non-exposed soil were unable to thrive at salinities above 15 ppt, and showed reduced growth rates even at low salt salinities (1-5 ppt). The findings suggest that heterotrophic soil flagellates are less tolerant to NaCl than their aquatic relatives, possibly due to their long evolutionary history in soil, and support the idea that identical morphospecies may differ considerably with respect to physiology PMID:12188223

Ekelund, Flemming

2002-01-01

295

Total mercury, methylmercury, and selected elements in soils of the Fishing Brook watershed, Hamilton County, New York, and the McTier Creek watershed, Aiken County, South Carolina, 2008  

USGS Publications Warehouse

Mercury is an element of on-going concern for human and aquatic health. Mercury sequestered in upland and wetland soils represents a source that may contribute to mercury contamination in sensitive ecosystems. An improved understanding of mercury cycling in stream ecosystems requires identification and quantification of mercury speciation and transport dynamics in upland and wetland soils within a watershed. This report presents data for soils collected in 2008 from two small watersheds in New York and South Carolina. In New York, 163 samples were taken from multiple depths or soil horizons at 70 separate locations near Fishing Brook, located in Hamilton County. At McTier Creek, in Aiken County, South Carolina, 81 samples from various soil horizons or soil depths were collected from 24 locations. Sample locations within each watershed were selected to characterize soil geochemistry in distinct land-cover compartments. Soils were analyzed for total mercury, selenium, total and carbonate carbon, and 42 other elements. A subset of the samples was also analyzed for methylmercury.

Woodruff, Laurel G.; Cannon, William F.; Knightes, Christopher D.; Chapelle, Francis H.; Bradley, Paul M.; Burns, Douglas A.; Brigham, Mark E.; Lowery, Mark A.

2010-01-01

296

[Distribution and species of mercury in water and sediments from Xiangjiang River section flowing through Zhuzhou, Xiangtan, Changsha].  

PubMed

Total mercury content in water in dry season is (1.881 +/- 1.854) microg x L(-1) in Xiangjiang River section flowing through Zhuzhou, Xiangtan, Changsha. Mercury in water is mainly in the form of particle mercury. The maxima of total mercury and soluble mercury content discovered in Xiawan attenuating rapidly in section of Xiawan-Xiangtan but slowly in section of Xiangtan-Lake Dongting. The average content of total mercury in sediment is 0.846 mg x kg(-1) up to the highest level in rivers of China. The highest content of total mercury discovered in Xiawan is 3.268 mg x kg(-1) which far more exceeds III-level soil pollution norms of China. In the section of Xiawan-Majiahe mercury mainly exists in sediment and average content total mercury (in sediments) is 2.218 mg x kg(-1). With coming down by a big margin total mercury content is 0.442 mg x kg(-1) in section of Yijiawan-Juzizhou. In the downstream of Changsha total mercury attenuating slowly. The mercury average content in pore-water of sediments is 0.035 microg x L(-1). There is no significant correlation between pore-water mercury and total mercury. Mercury (in sediments) is mainly in the form of residue, soluble plus exchangeable ions,and organic matter bound that will become active and pollution again. From upstream to downstream the fraction bound to organic matter decreases, but residue mercury increases to a small extent that indicates the change of mercury form from the organic matter bounded to the form of residue. In the section analysis of mercury (in sediments), Hg reaches 65 cm deep. As the locations close to sediments top, total mercury content increases until the distance to sediment top is 30-25 cm. PMID:21404673

Guo, Zhen-Hua; Peng, Qing-Lin; Liu, Chun-Hua; Liu, Zhi-Hua

2011-01-01

297

Heavy metal concentrations in feathers of common loons (Gavia immer) in the Northeastern United States and age differences in mercury levels.  

PubMed

Feathers serve as a useful, non-destructive approach for biomonitoring some aspects of environmental quality. Birds can eliminate over 90% of their body burden of mercury by sequestration in growing feathers, and they molt their feathers at least annually. Thus mercury concentrations should not vary in avian feathers as a function of age. We tested the null hypothesis that there are no age differences in the concentrations of mercury, lead, cadmium, selenium, copper, chromium and manganese in the feathers of immature and adult common loons Gavia immer from the Northeastern United States where the species is declining. Adults had significantly higher mean levels of mercury (20245 ppb) than immature loons (9677 ppb), but there were no age-related differences for other elements. Even with the small number of immatures, females had significantly higher levels of mercury than males, although the gender difference was not significant for adults. PMID:24213705

Burger, J; Pokras, M; Chafel, R; Gochfeld, M

1994-03-01

298

The processing of simulated high-level radioactive waste sludges containing nitrites and mercury  

SciTech Connect

The reaction of formic acid with simulated alkaline sludge containing mercury and nitrite was studied in an engineering-scale facility. Quantification of offgas production was performed, with the major offgases being CO{sub 2} and NO{sub x}. A small amount of CO was also found. The NO{sub x} was scrubbed in the offgas condenser and formed very acidic solutions of nitrous and nitric acids. These acids dissolved mercury that was stripped from the sludge. However, the overall efficiency of mercury stripping was greater than expected, and the final mercury concentration in the sludge was lower than expected. The NO{sub x} in the offgas also caused large temperature rises in the offgas system due to the exothermic reaction of NO with O{sub 2}. This temperature rise had a detrimental effect on the performance of the Formic Acid Vent Condenser, such that redesign is being contemplated. 6 refs., 6 figs., 3 tabs.

Zamecnik, J.R.; Hutson, N.D.; Ritter, J.A.; Carter, J.T.

1991-01-01

299

Behavior of mercury, lead, cesium, and uranyl ions on four SRS soils  

SciTech Connect

Samples of four Savannah River Site (SRS) soils were tested for sorption behavior with Hg{sup 2+}, Pb{sup 2+}, UO{sub 2}{sup 2+}, and Cs{sup +} ions. The purpose of the study was to determine the selectivity of the different soils for these ions alone and in the presence of the competing cations, H{sup +} and Ca{sup 2+}. Distribution constants, Kd`s, for the test ions in various solutions have been determined for the four soils. In general, sorption by all of the soils appeared to be more complex than a simple ion exchange or adsorption process. In particular, the presence of organic matter in soil increased the capacity of the soil due to its chelating ability. Similar soils did not react similarly toward each metal cation.

Bibler, J.P.; Marson, D.B.

1992-03-20

300

Behavior of mercury, lead, cesium, and uranyl ions on four SRS soils  

SciTech Connect

Samples of four Savannah River Site (SRS) soils were tested for sorption behavior with Hg[sup 2+], Pb[sup 2+], UO[sub 2][sup 2+], and Cs[sup +] ions. The purpose of the study was to determine the selectivity of the different soils for these ions alone and in the presence of the competing cations, H[sup +] and Ca[sup 2+]. Distribution constants, Kd's, for the test ions in various solutions have been determined for the four soils. In general, sorption by all of the soils appeared to be more complex than a simple ion exchange or adsorption process. In particular, the presence of organic matter in soil increased the capacity of the soil due to its chelating ability. Similar soils did not react similarly toward each metal cation.

Bibler, J.P.; Marson, D.B.

1992-03-20

301

Linking cellulose fiber sediment methyl mercury levels to organic matter decay and major element composition.  

PubMed

Methylation of mercury (Hg) to highly toxic methyl Hg (MeHg), a process known to occur when organic matter (OM) decomposition leads to anoxia, is considered a worldwide threat to aquatic ecosystems and human health. We measured temporal and spatial variations in sediment MeHg, total Hg (THg), and major elements in a freshwater lagoon in Sweden polluted with Hg-laden cellulose fibers. Fiber decomposition, confined to a narrow surface layer, resulted in loss of carbon (C), uptake of nitrogen (N), phosphorus (P), and sulfur (S), and increased MeHg levels. Notably, fiber decomposition and subsequent erosion of fiber residues will cause buried contaminants to gradually come closer to the sediment-water interface. At an adjacent site where decomposed fiber accumulated, there was a gain in C and a loss of S when MeHg increased. As evidenced by correlation patterns and vertical chemical profiles, reduced S may have fueled C-fixation and Hg methylation at this site. PMID:24420263

Regnell, Olof; Elert, Mark; Höglund, Lars Olof; Falk, Anna Helena; Svensson, Anders

2014-11-01

302

Inter- and intraclutch variation in egg mercury levels in marine bird species from the Canadian Arctic.  

PubMed

Mercury (Hg) is a toxic metal that has been of increasing concern in the Canadian Arctic. We measured total Hg in eggs of three marine birds (Arctic terns Sterna paradisaea, common eiders Somateria mollissima borealis, long-tailed ducks Clangula hyemalis) that breed in the Canadian Arctic, to compare Hg laying order effects from the same clutch and to examine Hg among species. Early-laid eggs of all three species had 24-48% higher Hg concentrations than late laid eggs. Arctic terns had approximately twice the concentration of Hg in their eggs as the two duck species, and Hg in eider eggs from the High Arctic was higher than Hg in eggs from the Low Arctic. Higher Hg in tern eggs was consistent with this species occupying a higher trophic position in marine food webs, as indicated by stable nitrogen isotope (delta(15)N) values. The egg-laying sequence may need to be considered for Hg biomonitoring studies where small samples sizes are planned, and early eggs may be preferable for such studies since early eggs may be more representative of potential maximum levels of Hg in the marine food webs. PMID:19962722

Akearok, Jason A; Hebert, Craig E; Braune, Birgit M; Mallory, Mark L

2010-01-15

303

Using soil surface gray level to determine surface soil water content  

Microsoft Academic Search

How to determine surface soil water content (SWC) quickly and accurately is fundamental in studying eco-hydrological processes\\u000a and their modeling. Here we use laboratory experiments to determine surface SWC using soil surface gray level (SGL) values.\\u000a A negatively exponential relationship exists between SGL and SWC, i.e., SGL increases with the decrease of SWC. SGL can be\\u000a estimated based on initial

YuanJun Zhu; YunQiang Wang; MingAn Shao

2010-01-01

304

Mercury toxicity in plants  

Microsoft Academic Search

Mercury poisoning has become a problem of current interest as a result of environmental pollution on a global scale. Natural\\u000a emissions of mercury form two-thirds of the input; manmade releases form about one-third. Considerable amounts of mercury\\u000a may be added to agricultural land with sludge, fertilizers, lime, and manures. The most important sources of contaminating\\u000a agricultural soil have been the

Manomita Patra; Archana Sharma

2000-01-01

305

Selenium speciation analysis at trace level in soils  

Microsoft Academic Search

This paper describes the development of an analytical methodology to determine speciation of selenium present in soils at trace level (?gkg?1). The methodology was based on parallel single extractions and high performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry (HPLC–ICPMS). Two complementary chromatographic separations were used to confirm Se species identity. Different extractants, selected on the basis of

Julie Tolu; Isabelle Le Hécho; Maďté Bueno; Yves Thiry; Martine Potin-Gautier

2011-01-01

306

Relationship between mercury accumulation in young-of-the-year yellow perch and water-level fluctuations  

USGS Publications Warehouse

A three-year (2001 -2003) monitoring effort of 14 northeastern Minnesota lakes was conducted to document relationships between water-level fluctuations and mercury bioaccumulation in young-of-the-year (YOY) yellow perch (Perca flavescens) collected in the fall of each year at fixed locations. Six of those lakes are located within or adjacent to Voyageurs National Park and are influenced by dams on the outlets of Rainy and Namakan lakes. One site on Sand Point Lake coincides with a location that has nine years of previous monitoring suitable for addressing the same issue over a longer time frame. Mean mercury concentrations in YOY yellow perch at each sampling location varied significantly from year to year. For the 12-year monitoring site on Sand Point Lake, values ranged from 38 ng gww-1 in 1998 to 200 ng gww -1 in 2001. For the 14-lake study, annual mean concentrations ranged by nearly a factor of 2, on average, for each lake over the three years of record. One likely factor responsible for these wide variations is that annual water-level fluctuations are strongly correlated with mercury levels in YOY perch for both data sets. ?? 2005 American Chemical Society.

Sorensen, J. A.; Kallemeyn, L. W.; Sydor, M.

2005-01-01

307

Effects of reservoir drawdown and refill on mercury levels in fish and other biota  

SciTech Connect

Mercury bioavailability from contaminated sediments is controlled by methylation, related to bacterial activity and degradable organic material. These variables may be affected by large changes in water level and chemistry in a reservoir. At Par Pond, a 1,200 ha impoundment on the USDOE Savannah River Site, South Carolina, potential failure of an earthen dam prompted lowering the reservoir by 3 meters over a two month period in 1991, decreasing water volume about 70%. The reservoir was refilled over a two month period in 1995. Largemouth bass (Micropterus salmoides) were sampled at quarterly intervals before, during and after the drawdown. Length and weight were determined, and liver and muscle analyzed for total Hg. Hg was also measured in top level predators (alligators), forage fish, macrophytes and invertebrates. From Fall 1991 Winter 1994--5, Hg ranged from 0.05 to 2.0 ug/g wet mass in bass muscle, and was strongly related to fish size, based on about 400 fish. Condition factor rose soon after drawdown, then declined as forage populations collapsed. Using fish size as covariate, bass muscle Hg was greater in spring 1992 than all other sampling dates. However, after 3 years of drawdown, there was no overall trend in bass Hg. Forage species differed in Hg, with highest concentrations in brook silversides (0.13 {micro}g Hg/g wet mass in 2 g fish). Alligators contained up to 20 {micro}g Hg/g dry mass in liver. Refill caused inundation of terrestrial plants on exposed sediments, and microbial action associated with the decay of these may enhance Hg methylation. Experiments with caged fish are underway to measure uptake rates.

Jagoe, C.H.; Salice, C.; Yabnochko, G.; Grasman, B.T.; Youngblood, T. [Savannah River Ecology Lab., Aiken, SC (United States)

1995-12-31

308

Comparison of mercury levels in various tissues of albino and pigmented mice treated with two different brands of mercury skin-lightening creams  

Microsoft Academic Search

The use of mercury containing skin-lightening creams are becoming increasingly popular among dark-skinned women. The long term use of certain brands may cause serious health effects over the years. In the present study, we investigated the dermal absorption of mercury and its accumulation in the tissues of albino and pigmented mice treated with two brands of mercury containing skin-lightening creams

Iman Al-Saleh; Neptune Shinwari; Inaam El-Doush; Grisellhi Billedo; Mona Al-Amodi; Fathia Khogali

2004-01-01

309

Bioconcentration of mercury by mushroom Xerocomus chrysenteron from the spatially distinct locations: levels, possible intake and safety.  

PubMed

Concentrations of mercury were determined in specimens of Red Cracking Bolete (Xerocomus chrysenteron) (Bull.) Quél. and overlying soil (0-10cm) collected from 22 spatially distributed sites in Poland during 1996-2013 to assess the potential of this species to bioconcentrate Hg and possible intake by humans. The mean Hg concentrations ranged from 80 to 630 for caps and from 28 to 380ng/g dry matter (dm) for stipes. Decrease in the potential of this mushroom species to bioconcentrate Hg both in caps and stipes was observed when the Hg content in soil substratum increased from 15 to 75-94ng/g dm. A maximum median value for bioconcentration factor (BCF) of Hg determined for caps was 18 for soil with Hg content at 15ng/g dm and decreased to 0.97-3.8 for soils that contained Hg at 37-94ng/g dm. Caps of X. chrysenteron consumed at a volume of 300g daily in a week can yield an exposure amount of Hg at 0.0168-0.1323mg (0.00024 to 0.00189mg/kg body mass); these values are well below the provisionally tolerated weekly intake (PTWI) for inorganic Hg. PMID:24927386

Dry?a?owska, Anna; Falandysz, Jerzy

2014-09-01

310

INVESTIGATION OF THE LIGHT ENHANCED EMISSION OF MERCURY FROM NATURALLY ENRICHED SUBSTRATES. (R827622E02)  

EPA Science Inventory

Incident radiation has been reported to facilitate mercury release from soils. In this study the influence of light on mercury emissions from substrates amended with pure synthetic mercury species, and from naturally and anthropogenically mercury-enriched substrates were inves...

311

Estimation and mapping of wet and dry mercury deposition across northeastern North America  

USGS Publications Warehouse

Whereas many ecosystem characteristics and processes influence mercury accumulation in higher trophic-level organisms, the mercury flux from the atmosphere to a lake and its watershed is a likely factor in potential risk to biota. Atmospheric deposition clearly affects mercury accumulation in soils and lake sediments. Thus, knowledge of spatial patterns in atmospheric deposition may provide information for assessing the relative risk for ecosystems to exhibit excessive biotic mercury contamination. Atmospheric mercury concentrations in aerosol, vapor, and liquid phases from four observation networks were used to estimate regional surface concentration fields. Statistical models were developed to relate sparsely measured mercury vapor and aerosol concentrations to the more commonly measured mercury concentration in precipitation. High spatial resolution deposition velocities for different phases (precipitation, cloud droplets, aerosols, and reactive gaseous mercury (RGM)) were computed using inferential models. An empirical model was developed to estimate gaseous elemental mercury (GEM) deposition. Spatial patterns of estimated total mercury deposition were complex. Generally, deposition was higher in the southwest and lower in the northeast. Elevation, land cover, and proximity to urban areas modified the general pattern. The estimated net GEM and RGM fluxes were each greater than or equal to wet deposition in many areas. Mercury assimilation by plant foliage may provide a substantial input of methyl-mercury (MeHg) to ecosystems. ?? 2005 Springer Science+Business Media, Inc.

Miller, E.K.; Vanarsdale, A.; Keeler, G.J.; Chalmers, A.; Poissant, L.; Kamman, N.C.; Brulotte, R.

2005-01-01

312

Correlates between feeding ecology and mercury levels in historical and modern arctic foxes (Vulpes lagopus).  

PubMed

Changes in concentration of pollutants and pathogen distribution can vary among ecotypes (e.g. marine versus terrestrial food resources). This may have important implications for the animals that reside within them. We examined 1) canid pathogen presence in an endangered arctic fox (Vulpes lagopus) population and 2) relative total mercury (THg) level as a function of ecotype ('coastal' or 'inland') for arctic foxes to test whether the presence of pathogens or heavy metal concentration correlate with population health. The Bering Sea populations on Bering and Mednyi Islands were compared to Icelandic arctic fox populations with respect to inland and coastal ecotypes. Serological and DNA based pathogen screening techniques were used to examine arctic foxes for pathogens. THg was measured by atomic absorption spectrometry from hair samples of historical and modern collected arctic foxes and samples from their prey species (hair and internal organs). Presence of pathogens did not correlate with population decline from Mednyi Island. However, THg concentration correlated strongly with ecotype and was reflected in the THg concentrations detected in available food sources in each ecotype. The highest concentration of THg was found in ecotypes where foxes depended on marine vertebrates for food. Exclusively inland ecotypes had low THg concentrations. The results suggest that absolute exposure to heavy metals may be less important than the feeding ecology and feeding opportunities of top predators such as arctic foxes which may in turn influence population health and stability. A higher risk to wildlife of heavy metal exposure correlates with feeding strategies that rely primarily on a marine based diet. PMID:23671561

Bocharova, Natalia; Treu, Gabriele; Czirják, Gábor Árpád; Krone, Oliver; Stefanski, Volker; Wibbelt, Gudrun; Unnsteinsdóttir, Ester Rut; Hersteinsson, Páll; Schares, Gereon; Doronina, Lilia; Goltsman, Mikhail; Greenwood, Alex D

2013-01-01

313

Correlates between Feeding Ecology and Mercury Levels in Historical and Modern Arctic Foxes (Vulpes lagopus)  

PubMed Central

Changes in concentration of pollutants and pathogen distribution can vary among ecotypes (e.g. marine versus terrestrial food resources). This may have important implications for the animals that reside within them. We examined 1) canid pathogen presence in an endangered arctic fox (Vulpes lagopus) population and 2) relative total mercury (THg) level as a function of ecotype (‘coastal’ or ‘inland’) for arctic foxes to test whether the presence of pathogens or heavy metal concentration correlate with population health. The Bering Sea populations on Bering and Mednyi Islands were compared to Icelandic arctic fox populations with respect to inland and coastal ecotypes. Serological and DNA based pathogen screening techniques were used to examine arctic foxes for pathogens. THg was measured by atomic absorption spectrometry from hair samples of historical and modern collected arctic foxes and samples from their prey species (hair and internal organs). Presence of pathogens did not correlate with population decline from Mednyi Island. However, THg concentration correlated strongly with ecotype and was reflected in the THg concentrations detected in available food sources in each ecotype. The highest concentration of THg was found in ecotypes where foxes depended on marine vertebrates for food. Exclusively inland ecotypes had low THg concentrations. The results suggest that absolute exposure to heavy metals may be less important than the feeding ecology and feeding opportunities of top predators such as arctic foxes which may in turn influence population health and stability. A higher risk to wildlife of heavy metal exposure correlates with feeding strategies that rely primarily on a marine based diet. PMID:23671561

Krone, Oliver; Stefanski, Volker; Wibbelt, Gudrun; Unnsteinsdottir, Ester Rut; Hersteinsson, Pall; Schares, Gereon; Doronina, Lilia; Goltsman, Mikhail; Greenwood, Alex D.

2013-01-01

314

Lead, mercury, cadmium, chromium, and arsenic levels in eggs, feathers, and tissues of Canada geese of the New Jersey Meadowlands.  

PubMed

The New Jersey Meadowlands are located within the heavily urbanized New York/New Jersey Harbor Estuary and have been subject to contamination due to effluent and runoff from industry, traffic, and homes along the Hackensack River and nearby waterways. These extensive wetlands, though heavily impacted by development and pollution, support a wide array of bird and other wildlife species. Persistent contaminants may pose threats to birds in these habitats, affecting reproduction, egg hatchability, nestling survival, and neurobehavioral development. Metals of concern in the Meadowlands include arsenic, cadmium, chromium, lead, and mercury. These metals were analyzed in eggs, feathers, muscle, and liver of Canada geese (Branta canadensis) breeding in four wetland sites. We sampled geese collected during control culling (n=26) and collected eggs from goose nests (n=34). Levels of arsenic were below the minimum quantification level (MQL) in most samples, and cadmium and mercury were low in all tissues sampled. Chromium levels were high in feather samples. Mercury levels in eggs of Canada geese, an almost exclusively herbivorous species, were lower (mean ±SE 4.29±0.30?g/g wet weight) than in eggs of omnivorous mallards (Anas platyrhynchos), and insectivorous red-winged blackbirds (Agelaius phoeniceus) and marsh wrens (Cistothorus palustris) from the Meadowlands, consistent with trophic level differences. However, lead levels were higher in the goose eggs (161±36.7ng/g) than in the other species. Geese also had higher levels of lead in feathers (1910±386ng/g) than those seen in Meadowlands passerines. By contrast, muscle and liver lead levels were within the range reported in waterfowl elsewhere, possibly a reflection of metal sequestration in eggs and feathers. Elevated lead levels may be the result of sediment ingestion or ingestion of lead shot and sinkers. Finally, lead levels in goose liver (249±44.7ng/g) and eggs (161±36.7ng/g) may pose a risk if consumed frequently by humans. Mill Creek, the site with the most documented prior contamination, had significantly elevated cadmium, chromium, mercury, and lead in goose tissues. PMID:21679937

Tsipoura, Nellie; Burger, Joanna; Newhouse, Michael; Jeitner, Christian; Gochfeld, Michael; Mizrahi, David

2011-08-01

315

Lead, mercury, cadmium, chromium, and arsenic levels in eggs, feathers, and tissues of Canada geese of the New Jersey Meadowlands  

SciTech Connect

The New Jersey Meadowlands are located within the heavily urbanized New York/New Jersey Harbor Estuary and have been subject to contamination due to effluent and runoff from industry, traffic, and homes along the Hackensack River and nearby waterways. These extensive wetlands, though heavily impacted by development and pollution, support a wide array of bird and other wildlife species. Persistent contaminants may pose threats to birds in these habitats, affecting reproduction, egg hatchability, nestling survival, and neurobehavioral development. Metals of concern in the Meadowlands include arsenic, cadmium, chromium, lead, and mercury. These metals were analyzed in eggs, feathers, muscle, and liver of Canada geese (Branta canadensis) breeding in four wetland sites. We sampled geese collected during control culling (n=26) and collected eggs from goose nests (n=34). Levels of arsenic were below the minimum quantification level (MQL) in most samples, and cadmium and mercury were low in all tissues sampled. Chromium levels were high in feather samples. Mercury levels in eggs of Canada geese, an almost exclusively herbivorous species, were lower (mean {+-}SE 4.29{+-}0.30 {mu}g/g wet weight) than in eggs of omnivorous mallards (Anas platyrhynchos), and insectivorous red-winged blackbirds (Agelaius phoeniceus) and marsh wrens (Cistothorus palustris) from the Meadowlands, consistent with trophic level differences. However, lead levels were higher in the goose eggs (161{+-}36.7 ng/g) than in the other species. Geese also had higher levels of lead in feathers (1910{+-}386 ng/g) than those seen in Meadowlands passerines. By contrast, muscle and liver lead levels were within the range reported in waterfowl elsewhere, possibly a reflection of metal sequestration in eggs and feathers. Elevated lead levels may be the result of sediment ingestion or ingestion of lead shot and sinkers. Finally, lead levels in goose liver (249{+-}44.7 ng/g) and eggs (161{+-}36.7 ng/g) may pose a risk if consumed frequently by humans. Mill Creek, the site with the most documented prior contamination, had significantly elevated cadmium, chromium, mercury, and lead in goose tissues. - Highlights: {yields} The NJ Meadowlands include extensive wetlands in the urban NYC metropolitan area. {yields} We analyzed eggs, feathers, muscle, and liver of Canada geese at 4 Meadowlands sites. {yields} As, Cd, and Hg were low in all tissues sampled, while Cr was high in feathers. {yields} Pb was higher in goose eggs and feathers than in other Meadowlands bird species. {yields} Pb in muscle and liver was lower and within the range seen in waterfowl elsewhere.

Tsipoura, Nellie [New Jersey Audubon Society, 11 Hardscrabble Road, Bernardsville, NJ 07924 (United States)] [New Jersey Audubon Society, 11 Hardscrabble Road, Bernardsville, NJ 07924 (United States); Burger, Joanna, E-mail: burger@biology.rutgers.edu [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States) [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States); Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States); Newhouse, Michael [NJ Meadowlands Commission, One DeKorte Park Plaza, Lyndhurst, NJ 07071 (United States)] [NJ Meadowlands Commission, One DeKorte Park Plaza, Lyndhurst, NJ 07071 (United States); Jeitner, Christian [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States) [Division of Life Sciences, 604 Allison Road, Piscataway, NJ 08854-8082 (United States); Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States); Gochfeld, Michael [Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States) [Environmental and Occupational Health Sciences Institute, Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ 08854 (United States); Environmental and Occupational Medicine. Robert Wood Johnson Medical School, 170 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Mizrahi, David [New Jersey Audubon Society, 11 Hardscrabble Road, Bernardsville, NJ 07924 (United States)] [New Jersey Audubon Society, 11 Hardscrabble Road, Bernardsville, NJ 07924 (United States)

2011-08-15

316

Goldilocks and three factors that make mercury in fish more than just mercury deposition: sulfur, land use and climate (Invited)  

NASA Astrophysics Data System (ADS)

The problem of mercury in fish is often framed as a problem created by anthropogenic emissions of mercury increasing the levels of mercury in the environment. But the methylation step that is crucial to making mercury available for bioaccumulation in the aquatic food web is influenced by more than just the concentration of mercury in the environment. Redox conditions, the quality of organic matter, and, in the case of methylation by sulfur reducing bacteria, the availability of sulfur, have all been shown to influence methylmercury concentrations in surface waters and/or mercury in the biota. This creates many possibilities for human influence on mercury bioaccumulation in freshwater fish. But it also creates possibilities for mitigating those human influences, if we can understand them. Forest harvest is one type of land use with a documented human influence on mercury levels in fish. Atmospheric deposition of sulfur is another potential influence on the mercury cycle, as is warming of the climate. Some for the possibilities for controlling the mercury problem may be overlooked by too much focus on mercury deposition and concentrations of total mercury in the landscape relative to these other factors. A range of field studies in FennoScandia published over the last 15 years were analyzed to explore the relative contribution of these different anthropogenic factors on the cycling of mercury. The studies included synoptic surveys across gradients of atmospheric deposition and land use (clear felling, site preparation and stump harvest) in relation to either fish mercury, sediment mercury, peat methylation potential or methylmercury concentrations in water. Long-term field manipulations (6-15 years) of land use (forest harvest) or combinations of sulphur deposition, nitrogen deposition and well greenhouse warming on peatland were also studied. The results suggest that the variation of total mercury in soils or water is less important than several of the other factors influenced by human activity. Two of the most important of these other factors are sulphur deposition and forest harvest. But these influences can also be neutralized by yet other factors (such as greenhouse warming in the case of sulphur deposition). This helps explain why different types of human influence have been so hard to discern from spatial and temporal patterns of mercury in fish, even though there is good reason to suggestion that forestry and atmospheric sulfur deposition are major factors in the mercury problem with regards to fish in FennoScandia and other high-latitude regions.

Bishop, K. H.; Eklöf, K.; Nilsson, M. B.; Osterwalder, S.; Ĺkerblom, S.

2013-12-01

317

New Jersey mercury regulations  

SciTech Connect

Mercury, or quicksilver, and its major ore cinnabar (HgS) have been known for thousands of years. Health effects from mercury such as dementia were known as early as the late 19th century ({open_quotes}mad as a hatter{close_quotes}). In the 1960`s and 1970`s, reported levels of mercury in tuna reawakened public awareness of mercury pollution. In the 1970`s, major epidemics of acute mercury poisoning were reported in Japan and Iraq. These incidents highlighted the extreme health risks, such as kidney damage, birth defects, and death, associated with severe mercury poisoning. Fetuses and young children are particularly vulnerable since mercury poisoning can damage growing neural tissues. Recently, the perception of mercury as a dangerous pollutant has been on the rise. Advisories warning the public to avoid or reduce the consumption of freshwater fish caught in specific waterbodies due to mercury contamination have been issued in numerous states. The discovery of mercury in {open_quotes}pristine{close_quotes} lakes in the United States, Canada, and Scandinavia, remote from industry and any known mercury sources, has focused attention on atmospheric emissions of mercury as potential significant sources of mercury.

Elias, D.F.; Corbin, W.E. [RTP Environmental Associates, Inc., Green Brook, NJ (United States)

1996-12-31

318

Sources of Mercury to East Fork Poplar Creek Downstream from the Y-12 National Security Complex: Inventories and Export Rates  

SciTech Connect

East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee, has been heavily contaminated with mercury (also referred to as Hg) since the 1950s as a result of historical activities at the U.S. Department of Energy (DOE) Y-12 National Security Complex (formerly the Oak Ridge Y-12 Plant and hereinafter referred to as Y-12). During the period from 1950 to 1963, spills and leaks of elemental mercury (Hg{sup 0}) contaminated soil, building foundations, and subsurface drainage pathways at the site, while intentional discharges of mercury-laden wastewater added 100 metric tons of mercury directly to the creek (Turner and Southworth 1999). The inventory of mercury estimated to be lost to soil and rock within the facility was 194 metric tons, with another estimated 70 metric tons deposited in floodplain soils along the 25 km length of EFPC (Turner and Southworth 1999). Remedial actions within the facility reduced mercury concentrations in EFPC water at the Y-12 boundary from > 2500 ng/L to about 600 ng/L by 1999 (Southworth et al. 2000). Further actions have reduced average total mercury concentration at that site to {approx}300 ng/L (2009 RER). Additional source control measures planned for future implementation within the facility include sediment/soil removal, storm drain relining, and restriction of rainfall infiltration within mercury-contaminated areas. Recent plans to demolish contaminated buildings within the former mercury-use areas provide an opportunity to reconstruct the storm drain system to prevent the entry of mercury-contaminated water into the flow of EFPC. Such actions have the potential to reduce mercury inputs from the industrial complex by perhaps as much as another 80%. The transformation and bioaccumulation of mercury in the EFPC ecosystem has been a perplexing subject since intensive investigation of the issue began in the mid 1980s. Although EFPC was highly contaminated with mercury (waterborne mercury exceeded background levels by 1000-fold, mercury in sediments by more than 2000-fold) in the 1980s, mercury concentrations in EFPC fish exceeded those in fish from regional reference sites by only a little more than 10-fold. This apparent low bioavailability of mercury in EFPC, coupled with a downstream pattern of mercury in fish in which mercury decreased in proportion to dilution of the upstream source, lead to the assumption that mercury in fish would respond to decreased inputs of dissolved mercury to the stream's headwaters. However, during the past two decades when mercury inputs were decreasing, mercury concentrations in fish in Lower EFPC (LEFPC) downstream of Y-12 increased while those in Upper EFPC (UEFPC) decreased. The key assumption of the ongoing cleanup efforts, and concentration goal for waterborne mercury were both called into question by the long-term monitoring data. The large inventory of mercury within the watershed downstream presents a concern that the successful treatment of sources in the headwaters may not be sufficient to reduce mercury bioaccumulation within the system to desired levels. The relative importance of headwater versus floodplain mercury sources in contributing to mercury bioaccumulation in EFPC is unknown. A mercury transport study conducted by the Tennessee Valley Authority (TVA) in 1984 estimated that floodplain sources contributed about 80% of the total annual mercury export from the EFPC system (ORTF 1985). Most of the floodplain inputs were associated with wet weather, high flow events, while much of the headwater flux occurred under baseflow conditions. Thus, day-to-day exposure of biota to waterborne mercury was assumed to be primarily determined by the Y-12 source. The objective of this study was to evaluate the results of recent studies and monitoring within the EFPC drainage with a focus on discerning the magnitude of floodplain mercury sources and how long these sources might continue to contaminate the system after headwater sources are eliminated or greatly reduced.

Southworth, George R [ORNL; Greeley Jr, Mark Stephen [ORNL; Peterson, Mark J [ORNL; Lowe, Kenneth Alan [ORNL; Ketelle, Richard H [ORNL; Floyd, Stephanie B [ORNL

2010-02-01

319

Mercury accumulation in bats near hydroelectric reservoirs in Peninsular Malaysia.  

PubMed

In large man-made reservoirs such as those resulting from hydroelectric dam construction, bacteria transform the relatively harmless inorganic mercury naturally present in soil and the submerged plant matter into toxic methylmercury. Methylmercury then enters food webs and can accumulate in organisms at higher trophic levels. Bats feeding on insects emerging from aquatic systems can show accumulation of mercury consumed through their insect prey. In this study, we investigated whether the concentration of mercury in the fur of insectivorous bat species was significantly higher than that in the fur of frugivorous bat species, sampled near hydroelectric reservoirs in Peninsular Malaysia. Bats were sampled at Temenggor Lake and Kenyir Lake and fur samples from the most abundant genera of the two feeding guilds-insectivorous (Hipposideros and Rhinolophus) and frugivorous (Cynopterus and Megaerops) were collected for mercury analysis. We found significantly higher concentrations of total mercury in the fur of insectivorous bats. Mercury concentrations also differed significantly between insectivorous bats sampled at the two sites, with bats from Kenyir Lake, the younger reservoir, showing higher mercury concentrations, and between the insectivorous genera, with Hipposideros bats showing higher mercury concentrations. Ten bats (H. cf. larvatus) sampled at Kenyir Lake had mercury concentrations approaching or exceeding 10 mg/kg, which is the threshold at which detrimental effects occur in humans, bats and mice. PMID:24840106

Syaripuddin, Khairunnisa; Kumar, Anjali; Sing, Kong-Wah; Halim, Muhammad-Rasul Abdullah; Nursyereen, Muhammad-Nasir; Wilson, John-James

2014-09-01

320

Riverine source of Arctic Ocean mercury inferred from atmospheric observations  

NASA Astrophysics Data System (ADS)

Methylmercury is a potent neurotoxin that accumulates in aquatic food webs. Human activities, including industry and mining, have increased inorganic mercury inputs to terrestrial and aquatic ecosystems. Methylation of this mercury generates methylmercury, and is thus a public health concern. Marine methylmercury is a particular concern in the Arctic, where indigenous peoples rely heavily on marine-based diets. In the summer, atmospheric inorganic mercury concentrations peak in the Arctic, whereas they reach a minimum in the northern mid-latitudes. Here, we use a global three-dimensional ocean-atmosphere model to examine the cause of this Arctic summertime maximum. According to our simulations, circumpolar rivers deliver large quantities of mercury to the Arctic Ocean during summer; the subsequent evasion of this riverine mercury to the atmosphere can explain the summertime peak in atmospheric mercury levels. We infer that rivers are the dominant source of mercury to the Arctic Ocean on an annual basis. Our simulations suggest that Arctic Ocean mercury concentrations could be highly sensitive to climate-induced changes in river flow, and to increases in the mobility of mercury in soils, for example as a result of permafrost thaw and forest fires.

Fisher, Jenny A.; Jacob, Daniel J.; Soerensen, Anne L.; Amos, Helen M.; Steffen, Alexandra; Sunderland, Elsie M.

2012-07-01

321

Chlorinated hydrocarbon and mercury levels in bald eagles (Haliaeetus leucocephalus) found dead in British Columbia, 1988--1993  

SciTech Connect

Liver samples from 70 bald eagles found dead or dying in British Columbia between 1988 and 1993 were analyzed for organochlorine and mercury levels. A subset of 11 eagles found around the Strait of Georgia, an area of known pulp mill pollution, in summer (and therefore presumably resident birds) were analyzed for polychlorinated dibenzo-p-dioxins (PCDDS) and polychlorinated dibenzofurans (PCDFs). Levels of DDE and PCBs ranged from less than 1 mg/kg to 190 and 65 mg/kg respectively. Levels of other organochlorines were generally less than 1 mg/kg, with the exception of some chlordane-related compounds which were occasionally over 2 mg/kg. All birds analyzed for PCDDs/PCDFs contained detectable levels of the major 2,378-substituted isomers. Some birds had extremely high levels, one eagle collected near a kraft pulp mill site contained: 400 ng/kg 2378-TCDD, 1400 ng/kg 12378-PnCDD and 4400 ng/kg 123678-HxCDD. All but two eagles had > 1 mg/kg dry wt. of mercury in liver; most contained less than 1 0 mg/kg d.w. but one bird had 130 mg/kg, a level of toxicological concern. All carcasses were autopsied and cause of death determined wherever possible. The relationship between cause of death and sublethal exposure to OCs and Hg is analyzed and discussed.

Elliott, J.E.; Wilson, L.K. [Canadian Wildlife Service, Delta, British Columbia (Canada); Norstrom, R.J. [Canadian Wildlife Service, Ottawa, Ontario (Canada); Langelier, K.M. [Island Veterinary Hospital, Nanaimo, British Columbia (Canada)

1994-12-31

322

Influence of illegal gold mining on mercury levels in fish of North Sulawesi's Minahasa Peninsula, (Indonesia)  

Microsoft Academic Search

North Sulawesi's Minahasa Peninsula currently is experiencing intense illegal gold mining activity. It has been estimated that 200 t of mercury are used annually in Indonesia in the recovery of gold from the illegal mines. To date no study has assessed the environmental impact of this illegal activity on the nearby aquatic biota. To address this concern, we compared tissue

Joice L. Kambey; A. p. Farrell; L. i. Bendell-young

2001-01-01

323

Measurement of cesium and mercury emissions from the vitrification of simulated high level radioactive waste  

SciTech Connect

In the Defense Waste Processing Facility at the Savannah River Site, it is desired to measure non-radioactive cesium in the offgas system from the glass melter. From a pilot scale melter system, offgas particulate samples were taken on filter paper media and analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The ICP-MS method proved to be sufficiently sensitive to measure cesium quantities as low as 0.135 {mu}g, with the sensitivity being limited by the background cesium present in the filter paper. This sensitivity allowed determination of cesium decontamination factors for four of the five major components of the offgas system. In addition, total particulate measurements were also made. Measurements of mercury decontamination factors were made on the same equipment; the results indicate that most of the mercury in the offgas system probably exists as elemental mercury and HgCl{sub 2}, with some HgO and Hg{sub 2}Cl{sub 2}. The decontamination factors determined for cesium, total particulate, and mercury all compared favorably with the design values.

Zamecnik, J.R.

1992-12-31

324

LEVEL AND EXTENT OF MERCURY CONTAMINATION IN OREGON, USA, LOTIC FISH  

EPA Science Inventory

Because of growing concern with widespread mercury contamination of fish tissue, we sampled 154 streams and rivers throughout Oregon using a probability design. To maximize the sample size we took samples of small and large fish, where possible, from wadeable streams and boatable...

325

Inter and intraclutch variation in egg mercury levels in marine bird species from the Canadian Arctic  

Microsoft Academic Search

Mercury (Hg) is a toxic metal that has been of increasing concern in the Canadian Arctic. We measured total Hg in eggs of three marine birds (Arctic terns Sterna paradisaea, common eiders Somateria mollissima borealis, long-tailed ducks Clangula hyemalis) that breed in the Canadian Arctic, to compare Hg laying order effects from the same clutch and to examine Hg among

Jason A. Akearok; Craig E. Hebert; Birgit M. Braune; Mark L. Mallory

2010-01-01

326

DEVELOPMENT OF ECOLOGICAL SOIL SCREENING LEVELS FOR SOIL INVERTEBRATES AND PLANTS FROM PEER-REVIEWED LITERATURE  

EPA Science Inventory

The U.S. Environmental Protection Agency, as part of a collaborative effort among government and industry representatives, is developing Ecologic Soil Screening Levels (Eco-SSLs) for approximately 25 of the most common pollutants found at Superfund sites. As part of this effort, ...

327

The organic contamination level based on the total soil mass is not a proper index of the soil contamination intensity  

USGS Publications Warehouse

Concentrations of organic contaminants in common productive soils based on the total soil mass give a misleading account of actual contamination effects. This is attributed to the fact that productive soils are essentially water-saturated, with the result that the soil uptake of organic compounds occurs principally by partition into the soil organic matter (SOM). This report illustrates that the soil contamination intensity of a compound is governed by the concentration in the SOM (Com) rather than by the concentration in whole soil (Cs). Supporting data consist of the measured levels and toxicities of many pesticides in soils of widely differing SOM contents and the related levels in in-situ crops that defy explanation by the Cs values. This SOM-based index is timely needed for evaluating the contamination effects of food crops grown in different soils and for establishing a dependable priority ranking for intended remediation of numerous contamination sites.

Hung, H. -W.; Daniel, Sheng, G.; Lin, T. -F.; Su, Y.; Chiou, C. T.

2009-01-01

328

Phytoremediation of Ionic and Methyl Mercury P  

SciTech Connect

Our long-term goal is to enable highly productive plant species to extract, resist, detoxify, and/or sequester toxic heavy metal pollutants as an environmentally friendly alternative to physical remediation methods. We have focused this phytoremediation research on soil and water-borne ionic and methylmercury. Mercury pollution is a serious world-wide problem affecting the health of human and wild-life populations. Methylmercury, produced by native bacteria at mercury-contaminated wetland sites, is a particularly serious problem due to its extreme toxicity and efficient biomagnification in the food chain. We engineered several plant species (e.g., Arabidopsis, tobacco, canola, yellow poplar, rice) to express the bacterial genes, merB and/or merA, under the control of plant regulatory sequences. These transgenic plants acquired remarkable properties for mercury remediation. (1) Transgenic plants expressing merB (organomercury lyase) extract methylmercury from their growth substrate and degrade it to less toxic ionic mercury. They grow on concentrations of methylmercury that kill normal plants and accumulate low levels of ionic mercury. (2) Transgenic plants expressing merA (mercuric ion reductase) extract and electrochemically reduce toxic, reactive ionic mercury to much less toxic and volatile metallic mercury. This metal transformation is driven by the powerful photosynthetic reducing capacity of higher plants that generates excess NADPH using solar energy. MerA plants grow vigorously on levels of ionic mercury that kill control plants. Plants expressing both merB and merA degrade high levels of methylmercury and volatilize metallic mercury. These properties were shown to be genetically stable for several generations in the two plant species examined. Our work demonstrates that native trees, shrubs, and grasses can be engineered to remediate the most abundant toxic mercury pollutants. Building on these data our working hypothesis for the next grant period is that transgenic plants expressing the bacterial merB and merA genes will (a) remove mercury from polluted soil and water and (b) prevent methylmercury from entering the food chain. Our specific aims center on understanding the mechanisms by which plants process the various forms of mercury and volatilize or transpire mercury vapor. This information will allow us to improve the design of our current phytoremediation strategies. As an alternative to volatilizing mercury, we are using several new genes to construct plants that will hyperaccumulate mercury in above-ground tissues for later harvest. The Department of Energy's Oak Ridge National Laboratory and Brookhaven National Laboratory have sites with significant levels of mercury contamination that could be cleaned by applying the scientific discoveries and new phytoremediation technologies described in this proposal. The knowledge and expertise gained by engineering plants to hyperaccumulate mercury can be applied to the remediation of other heavy metals pollutants (e.g., arsenic, cesium, cadmium, chromium, lead, strontium, technetium, uranium) found at several DOE facilities.

Meagher, Richard B.

1999-06-01

329

DIETARY METHYL MERCURY EXPOSURE IN AMERICAN KESTRELS; PILOT STUDY  

EPA Science Inventory

Anthropogenic mercury emissions have increased atmospheric mercury levels about threefold since the advent of industrial activity. Atmospheric deposition is the primary source of mercury in the environment hence mercury contamination has increased in similar fashion. Methyl mercu...

330

Mercury speciation and mobilization in contaminated soils of the Valle del Azogue Hg mine (SE, Spain)  

NASA Astrophysics Data System (ADS)

Hg mobilization from contaminated soils and mine wastes was the source of environmental contamination in the Valle del Azogue mining area. We researched solid-phase speciation and aqueous mobility of Hg through Scanning electron microscopy-energy dispersive X-ray spectroscopy and electron probe microanalysis analysis, solid-phase-Hg-thermo-desorption (SPTD) and laboratory column experiments. We found that in contaminated soils and mine wastes, the predominant Hg species was cinnabar (HgS), mainly formed from the weathering of Hg-rich pyrite, and metallic Hg (0) in the matrix, whereas in calcines and tailings the dominant species was metallic Hg (0). The mobilization of Hg in the aqueous phase seems to have originated from the dissolution of elemental Hg (0) present in soils and wastes, reaching concentrations of up to 67 ?g l-1, and showing a higher long-term environmental potential risk, in addition to atmospheric emissions.

Navarro, A.; Biester, H.; Mendoza, J. L.; Cardellach, E.

2006-04-01

331

Effects of remediation train sequence on decontamination of heavy metal-contaminated soil containing mercury.  

PubMed

When a contaminated site contains pollutants including both nonvolatile metals and Hg, one single remediation technology may not satisfactorily remove all contaminants. Therefore, in this study, chemical extraction and thermal treatment were combined as a remediation train to remove heavy metals, including Hg, from contaminated soil. A 0.2 M solution of ethylenediamine tetraacetic acid (EDTA) was shown to be the most effective reagent for extraction of considerable amounts of Cu, Pb, and Zn (> 50%). Hg removal was ineffective using 0.2 M EDTA, but thermogravimetric analysis suggested that heating to 550 degrees C with a heating rate of 5 degrees C/min for a duration of 1 hr appeared to be an effective approach for Hg removal. With the employment of thermal treatment, up to 99% of Hg could be removed. However executing thermal treatment prior to chemical extraction reduced the effectiveness of the subsequent EDTA extraction because nonvolatile heavy metals were immobilized in soil aggregates after the 550 degrees C treatment. The remediation train of chemical extraction followed by thermal treatment appears to remediate soils that have been contaminated by many nonvolatile heavy metals and Hg. Implications: A remediation train conjoining two or more techniques has been initialized to remove multiple metals. Better understandings of the impacts of treatment sequences, namely, which technique should be employed first on the soil properties and the decontamination efficiency, are in high demand. This study provides a strategy to remove multiple heavy metals including Hg from a contaminated soil. The interactions between thermal treatment and chemical extraction on repartitioning of heavy metals was revealed. The obtained results could offer an integrating strategy to remediate the soil contaminated with both heavy metals and volatile contaminants. PMID:25282998

Hseu, Zeng-Yei; Huang, Yu-Tuan; Hsi, Hsing-Cheng

2014-09-01

332

Mercury Calculator  

NSDL National Science Digital Library

This interactive calculator produced by Teachers' Domain helps you determine the mercury levels in various types of fish, and enables you to make more informed choices about which fish are safe to eat and which should be avoided or eaten infrequently.

Foundation, Wgbh E.

2010-12-23

333

Mercury exposure, serum antinuclear/antinucleolar antibodies, and serum cytokine levels in mining populations in Amazonian Brazil: a cross-sectional study.  

PubMed

Mercury is an immunotoxic substance that has been shown to induce autoimmune disease in rodent models, characterized by lymphoproliferation, overproduction of immunoglobulin (IgG and IgE), and high circulating levels of auto-antibodies directed at antigens located in the nucleus (antinuclear auto-antibodies, or ANA) or the nucleolus (antinucleolar auto-antibodies, or ANoA). We have reported elevated levels of ANA and ANoA in human populations exposed to mercury in artisanal gold mining, though other confounding variables that may also modulate ANA/ANoA levels were not well controlled. The goal of this study is to specifically test whether occupational and environmental conditions (other than mercury exposure) that are associated with artisanal gold mining affect the prevalence of markers of autoimmune dysfunction. We measured ANA, ANoA, and cytokine concentrations in serum and compared results from mercury-exposed artisanal gold miners to those from diamond and emerald miners working under similar conditions and with similar socio-economic status and risks of infectious disease. Mercury-exposed gold miners had higher prevalence of detectable ANA and ANoA and higher titers of ANA and ANoA as compared to diamond and emerald miners with no occupational mercury exposure. Also, mercury-exposed gold miners with detectable ANA or ANoA in serum had significantly higher concentrations of pro-inflammatory cytokines IL-1beta, TNF-alpha, and IFN-gamma in serum as compared to the diamond and emerald miners. This study provides further evidence that mercury exposure may lead to autoimmune dysfunction and systemic inflammation in affected populations. PMID:20176347

Gardner, Renee M; Nyland, Jennifer F; Silva, Ines A; Ventura, Ana Maria; de Souza, Jose Maria; Silbergeld, Ellen K

2010-05-01

334

A COUPLED MONITORING NETWORK TO CONDUCT AN ASSESSMENT OF MERCURY TRANSFORMATION AND MOBILIZATION IN FLOODPLAIN SOILS  

E-print Network

drainage of precipitation, and upgradient groundwater flow; (2) drainage occurs predominantly through, temperature (Decagon) · Sampling and analysis of soil cores, stream water, and shallow groundwater · Well) METHODS RESULTS THg = 1202 mg/kg, dry weight! USGS 01626850 SOUTH RIVER NEAR DOOMS, VA

Sparks, Donald L.

335

SULFUR POLYMER STABILIZATION/SOLIDIFICATION TREATABILITY STUDY OF MERCURY CONTAMINATED SOIL FROM THE Y-12 SITE  

E-print Network

ENVIRONMENTAL SCIENCES DEPARTMENT BROOKHAVEN NATIONAL LABORATORY UPTON, NY 11973 #12;ii Executive Summary Procedure (TCLP) testing by an independent laboratory. Those containing 50 and 60 wt% soil easily met OAK RIDGE, TN November 2012 Environmental Sciences Department/Energy Research and Technology Division

Johnson, Peter D.

336

Mercury pollution of effluent, air, and soil near a battery factory in Tanzania  

Microsoft Academic Search

Effluent, air, and soil samples near a battery factory in Dar es Salaam, Tanzania, where HgCl2 is used to prevent mold growth, were collected to explore the potential for pollution of the environment from industrial discharge of Hg. Flameless atomic absorption spectrophotometry was used for Hg determinations. The concentration of Hg in the effluent ranged from -1 and the Hg

E. Semu; B. R. Singh; A. R. Selmer-Olsen

1986-01-01

337

MERCURY DEPOSITION AND LAKE QUALITY TRENDS  

EPA Science Inventory

Watershed factors influence the differing trends in mercury residue levels. Fish mercury concentrations show positive correlations with water color, methylmercury concentrations, and plankton mercury, and negative correlations with pH and alkalinity....

338

Mercury levels of Nelson’s and saltmarsh sparrows at wintering grounds in Virginia, USA  

Microsoft Academic Search

Nelson’s and saltmarsh sparrows (Ammodramus nelsoni and A. caudacutus) have recently been recognized as separate species, and because of their limited distributions and the susceptibility of\\u000a their wetland habitats to climate change, these two new species are of conservation concern. Both species are known to bioaccumulate\\u000a mercury at breeding sites in New England, USA where their ranges overlap, with the

Daniel A. CristolFletcher; Fletcher M. Smith; Claire W. Varian-Ramos; Bryan D. Watts

339

Interrelationships between mercury levels in yearling yellow perch, fish condition and water quality  

Microsoft Academic Search

Yearling yellow perch were collected from sixteen Muskoka-Haliburton lakes to determine interrelationships between water quality, Hg residues in fish and fish condition. The lakes studied were Precambrian shield lakes with a pH range of 5.6 to 7.3 and total inflection point alkalinities of 0.4 to 16.0 mg L-1. Mercury residues in yellow perch ranged from 31 to 233 ng g-1

K. Suns; G. Hitchin

1990-01-01

340

Temporal Trends in Beluga, Narwhal and Walrus Mercury Levels: Links to Climate Change  

Microsoft Academic Search

\\u000a The exposure of Arctic marine mammals to contaminants may change via ecological dynamics in response to climate change. For\\u000a example, changes to the structure of the food web or shifts in regional foraging could affect dietary exposure. We examined\\u000a the temporal variation of total mercury (THg) concentrations in Hudson Bay beluga (Delphinapterus leucas) and Foxe Basin walrus (Odobenus rosmarus rosmarus)

A. Gaden; G. A. Stern

341

Cadmium in Soil and Winter Wheat Grain in Southern Sweden: I. Factors Influencing Cd Levels in Soils and Grain  

Microsoft Academic Search

The guideline level for Cd contents in cereals of 100 ?g kg proposed by the Codex Committee on Cereals, Pulses and Legumes has increased concern regarding Cd levels in Swedish winter wheat. In this study, Cd levels in soil and grain and factors influencing these variables were investigated in Skĺne, the southernmost province in Sweden. In 1992, soils and winter

Jan. E. Eriksson; Mats Söderström

1996-01-01

342

Tuna fish diet influences cat behavior. [Elevated levels of selenium and mercury in commercial tuna fish cat food  

SciTech Connect

When observed in their home cages, cats fed commercial tuna fish cat food were less active, vocalized less, and spent more time on the floor and more time eating than cats fed commercial beef cat food. There were no differences in response to human handling between the two groups. There were no differences in learning ability on a two-choice point maze or in reversal learning in the same maze between beef- and tuna-fed cats. The behavior of the groups differed in a 15-min open field test only in the number of toys contacted. Cats fed the tuna had elevated tissue levels of mercury and selenium.

Houpt, K.A.; Essick, L.A.; Shaw, E.B.; Alo, D.K.; Gilmartin, J.E.; Gutenmann, W.H.; Littman, C.B.; Lisk, D.J.

1988-01-01

343

Residue levels of polychlorobiphenyls, ?DDT, and mercury in bird species commonly preyed upon by the peregrine falcon ( Falco peregrinus Tunst.) in Sweden  

Microsoft Academic Search

The levels of polychlorobiphenyls (PCBs), SDDT, and total mercury were analyzed in samples of common prey species of the peregrine falcon in two falcon territories, one in northern and one in southern Sweden. Resident and herbivorous prey species showed low residue levels, while elevated levels were found in birds feeding on animals in aquatic habitats. According to biomass, waders accounted

Peter Lindberg; Tjelvar Odsjö; Lars Reutergftrdh

1985-01-01

344

Influence of Cadmium and Mercury on Activities of Ligninolytic Enzymes and Degradation of Polycyclic Aromatic Hydrocarbons by Pleurotus ostreatus in Soil  

PubMed Central

The white-rot fungus Pleurotus ostreatus was able to degrade the polycyclic aromatic hydrocarbons (PAHs) benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, and benzo[ghi]perylene in nonsterile soil both in the presence and in the absence of cadmium and mercury. During 15 weeks of incubation, recovery of individual compounds was 16 to 69% in soil without additional metal. While soil microflora contributed mostly to degradation of pyrene (82%) and benzo[a]anthracene (41%), the fungus enhanced the disappearance of less-soluble polycyclic aromatic compounds containing five or six aromatic rings. Although the heavy metals in the soil affected the activity of ligninolytic enzymes produced by the fungus (laccase and Mn-dependent peroxidase), no decrease in PAH degradation was found in soil containing Cd or Hg at 10 to 100 ppm. In the presence of cadmium at 500 ppm in soil, degradation of PAHs by soil microflora was not affected whereas the contribution of fungus was negligible, probably due to the absence of Mn-dependent peroxidase activity. In the presence of Hg at 50 to 100 ppm or Cd at 100 to 500 ppm, the extent of soil colonization by the fungus was limited. PMID:10831426

Baldrian, Petr; in der Wiesche, Carsten; Gabriel, Jiri; Nerud, Frantisek; Zadrazil, Frantisek

2000-01-01

345

Groundwater Modeling Of Mercury Pollution At A Former Mercury Cell Chlor Alkali Facility In Pavoldar, Kazakhstan  

EPA Science Inventory

In Kazakhstan, there is a serious case of mercury pollution near the city of Pavlodar from an old mercury cell chlor-alkali plant. The soil, sediment, and water is severly contaminated with mercury and mercury compounds as a result of the industrial activity of this chemical pla...

346

Concentration, distribution, and translocation of mercury and methylmercury in mine-waste, sediment, soil, water, and fish collected near the Abbadia San Salvatore mercury mine, Monte Amiata district, Italy  

USGS Publications Warehouse

The distribution and translocation of mercury (Hg) was studied in the Paglia River ecosystem, located downstream from the inactive Abbadia San Salvatore mine (ASSM). The ASSM is part of the Monte Amiata Hg district, Southern Tuscany, Italy, which was one of the world’s largest Hg districts. Concentrations of Hg and methyl-Hg were determined in mine-waste calcine (retorted ore), sediment, water, soil, and freshwater fish collected from the ASSM and the downstream Paglia River. Concentrations of Hg in calcine samples ranged from 25 to 1500 ?g/g, all of which exceeded the industrial soil contamination level for Hg of 5 ?g/g used in Italy. Stream and lake sediment samples collected downstream from the ASSM ranged in Hg concentration from 0.26 to 15 ?g/g, of which more than 50% exceeded the probable effect concentration for Hg of 1.06 ?g/g, the concentration above which harmful effects are likely to be observed in sediment-dwelling organisms. Stream and lake sediment methyl-Hg concentrations showed a significant correlation with TOC indicating considerable methylation and potential bioavailability of Hg. Stream water contained Hg as high as 1400 ng/L, but only one water sample exceeded the 1000 ng/L drinking water Hg standard used in Italy. Concentrations of Hg were elevated in freshwater fish muscle samples and ranged from 0.16 to 1.2 ?g/g (wet weight), averaged 0.84 ?g/g, and 96% of these exceeded the 0.3 ?g/g (methyl-Hg, wet weight) USEPA fish muscle standard recommended to protect human health. Analysis of fish muscle for methyl-Hg confirmed that > 90% of the Hg in these fish is methyl-Hg. Such highly elevated Hg concentrations in fish indicated active methylation, significant bioavailability, and uptake of Hg by fish in the Paglia River ecosystem. Methyl-Hg is highly toxic and the high Hg concentrations in these fish represent a potential pathway of Hg to the human food chain.

Rimondi, V.; Gray, J. E.; Costagliola, P.; Vaselli, O.; Lattanzi, P.

2012-01-01

347

Concentration, distribution, and translocation of mercury and methylmercury in mine-waste, sediment, soil, water, and fish collected near the Abbadia San Salvatore mercury mine, Monte Amiata district, Italy.  

PubMed

The distribution and translocation of mercury (Hg) was studied in the Paglia River ecosystem, located downstream from the inactive Abbadia San Salvatore mine (ASSM). The ASSM is part of the Monte Amiata Hg district, Southern Tuscany, Italy, which was one of the world's largest Hg districts. Concentrations of Hg and methyl-Hg were determined in mine-waste calcine (retorted ore), sediment, water, soil, and freshwater fish collected from the ASSM and the downstream Paglia River. Concentrations of Hg in calcine samples ranged from 25 to 1500 ?g/g, all of which exceeded the industrial soil contamination level for Hg of 5 ?g/g used in Italy. Stream and lake sediment samples collected downstream from the ASSM ranged in Hg concentration from 0.26 to 15 ?g/g, of which more than 50% exceeded the probable effect concentration for Hg of 1.06 ?g/g, the concentration above which harmful effects are likely to be observed in sediment-dwelling organisms. Stream and lake sediment methyl-Hg concentrations showed a significant correlation with TOC indicating considerable methylation and potential bioavailability of Hg. Stream water contained Hg as high as 1400 ng/L, but only one water sample exceeded the 1000 ng/L drinking water Hg standard used in Italy. Concentrations of Hg were elevated in freshwater fish muscle samples and ranged from 0.16 to 1.2 ?g/g (wet weight), averaged 0.84 ?g/g, and 96% of these exceeded the 0.3 ?g/g (methyl-Hg, wet weight) USEPA fish muscle standard recommended to protect human health. Analysis of fish muscle for methyl-Hg confirmed that >90% of the Hg in these fish is methyl-Hg. Such highly elevated Hg concentrations in fish indicated active methylation, significant bioavailability, and uptake of Hg by fish in the Paglia River ecosystem. Methyl-Hg is highly toxic and the high Hg concentrations in these fish represent a potential pathway of Hg to the human food chain. PMID:22169390

Rimondi, Valentina; Gray, John E; Costagliola, Pilario; Vaselli, Orlando; Lattanzi, Pierfranco

2012-01-01

348

A comparison of the dynamics and bioconcentration of mercury in Oregon reservoirs  

SciTech Connect

The authors assessed the extent of mercury pollution and its bioconcentration effects in fish in two Oregon reservoirs. Cottage Grove and Dorena Reservoirs are located in same ecoregions but distinguished by the history of mercury mining in the formers watershed. Past mercury mining activity deposited up to 271 {micro}g/g mercury and 2.6 mg/g sulfur in soils of near Black Butte Mine, OR. Sediment mercury concentration in the main tributary of Cottage Grove Reservoir, which drains the tailings of the past mercury mine, was ten times higher than in sediment from other tributaries to the reservoir. However there was no significantly difference between mercury concentration in each tributary of Dorena Reservoir, which has no mercury mining history in its watershed. Average mercury concentration in sediment of Cottage Grove Reservoir (0.67 {micro}g/g dw) was higher than of Dorena Reservoir (0.12 {micro}g/g dw). The authors also determined percent volatile solid and grain size effect in sediment. Maximum mercury concentration exceeded the FDA limit 1 {micro}g/g ww for largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus) in Cottage Grove Reservoir. All fish species (largemouth bass, bluegill, crappie (Pomoxis nigromaculatus), catfish (Ictalurus nebulosus)) from Cottage Grove Reservoir had significantly higher levels of mercury than from Dorena Reservoir. Fish weight and age was positively correlated with mercury concentration in both-reservoirs and seasonal variation of mercury concentration in fish was examined. These results indicate that the Black Butte Mine is the main source of mercury and mercury bioconcentration in fish represents a management problem in Cottage Grove Reservoir.

Park, J. [Oregon State Univ., Corvallis, OR (United States); Curtis, L. [East Tennessee State Univ., Johnson City, TN (United States). Dept. of Environmental Health

1995-12-31

349

Mercury pollution in the soil and mosses around a geothermal plant  

Microsoft Academic Search

Samples of soils and mosses were collected near a geothermal power plant, which is located in one of the most active geothermal fields of the world (Southern Tuscany). High concentrations of Hg (up to 1.8 µg g-1 d.w.) occur in mosses as far as 0.6 km from the geothermal plant, and the Hg uptake of mosses is unrelated to the

Franco Baldi

1988-01-01

350

MERCURY LEVELS IN FISH FROM THE UPPER PENINSULA OF MICHIGAN (ELS SUBREGION 2B) IN RELATION TO LAKE ACIDITY  

EPA Science Inventory

The accumulation of mercury by fish and the potential human health effects of eating mercury-contaminated fish have been well documented. owever, elevated mercury concentrations in fish from dilute, low-pH lakes have only recently been associated with increased lake acidity. ever...

351

Styrofoam debris as a potential carrier of mercury within ecosystems.  

PubMed

The present paper falls within the trend of research into interactions between various pollutants emitted anthropogenically into the environment and focuses on mercury and styrofoam debris. The study covers part of the Southern Baltic's drainage area. Apart from styrofoam and beach sand, the research involved mosses, which are bioindicators of atmospheric metal pollution. The research has shown that mercury present in the environment becomes associated with styrofoam debris. The median for mercury concentrations in virgin styrofoam samples (0.23 ng g(-1) dry weight (d.w.)) and in beach sand samples (0.69 ng g(-1) d.w.) was an order of magnitude lower than in the styrofoam debris (5.20 ng g(-1) d.w.). The highest mercury content observed in styrofoam debris (3,863 ng g(-1) d.w.) exceeded the standards for bottom sediment and soil. The binding of mercury to styrofoam debris takes place in water, and presumably also through contact with the ground. A significant role in this process was played by biotic factors, such as the presence of biofilm and abiotic ones, such as solar radiation and the transformations of mercury forms related to it. As a result, mercury content in styrofoam debris underwent seasonal changes, peaking in summertime. Furthermore, the regional changes of mercury content in the studied debris seem to reflect the pollution levels of the environment. PMID:24057963

Graca, Bo?ena; Be?dowska, Magdalena; Wrzesie?, Patrycja; Zgrundo, Aleksandra

2014-02-01

352

Temporal trends (1989–2011) in levels of mercury and other heavy metals in feathers of fledgling great egrets nesting in Barnegat Bay, NJ  

SciTech Connect

There is an abundance of data for levels of metals from a range of species, but relatively few long-term time series from the same location. In this paper I examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from fledgling great egrets (Ardea alba) collected at nesting colonies in Barnegat Bay, New Jersey from 1989 to 2011. The primary objectives were to test the null hypotheses that (1) There were no temporal differences in metal levels in feathers of fledgling great egrets, and (2) Great egrets nesting in different areas of Barnegat Bay (New Jersey) did not differ in metal levels. There were significant yearly variations in levels of all heavy metals in feathers of fledgling great egret, but levels decreased significantly from 1989 to 2011 only for lead (1470 ppb to 54.3 ppb), cadmium (277 ppb to 30.5 ppb), and manganese (only since 1996; 2669 ppb to 329 ppb)). Although mercury levels decreased from 2003–2008 (6430 ppb to 1042 ppb), there was no pattern before 2003, and levels increased after 2008 to 2610 ppb in 2011. Lead, cadmium, chromium, manganese and mercury were higher in feathers from great egrets nesting in the northern part of the bay, and selenium was highest in feathers from mid-bay. The lack of a temporal decline in mercury levels in feathers of great egrets is cause for concern, since the high levels in feathers from some years (means as high as 6430 ppb) are in the range associated with adverse effects (5000 ppb for feathers). -- Highlights: ? Metals were monitored in feathers of great egrets from Barnegat Bay, New Jersey. ? Levels of cadmium and lead decreased significantly from 1989–2011. ? Mercury levels in feathers from great egrets did not decline from 1989–2011. ? Metal levels were generally higher in great egrets and black-crowned night heron feathers than in snowy egrets.

Burger, Joanna, E-mail: burger@biology.rutgers.edu [Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, New Jersey 08854-8082, USA and also with Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, New Jersey (United States)] [Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, New Jersey 08854-8082, USA and also with Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, New Jersey (United States)

2013-04-15

353

Methodology for using contaminated soil leachability testing to determine soil cleanup levels at contaminated petroleum underground storage tank (UST) sites  

Microsoft Academic Search

The costs of environmental remediation at leaking petroleum underground storage tank (UST) sites are influenced significantly by soil cleanup levels. The use of conservative generic soil cleanup levels may be inappropriate at some sites contaminated by leaking petroleum USTs. At many contaminated sites, a primary objective of site remediation is long?term protection of water resources (e.g., groundwater) from pollution. Leaching

John R. Odermatt; John A. Menatti

1996-01-01

354

Comparative baseline levels of mercury, Hsp 70 and Hsp 60 in subsistence fish from the Yukon-Kuskokwim delta region of Alaska.  

PubMed

In subsistence fish; northern pike (Esox lucius), burbot (Lota lota), whitefish (Coregonus nelsoni), grayling (Thymallus arcticus) and sheefish (Stenodus lencichthys), we determined the Hsp 60 and Hsp 70 levels in 31 samples from adult fish gills. A dot-blot analysis using antibodies to either Hsp 70 or Hsp 60 showed the average Hsp 70 concentration was 9.1 microg/mg protein, while the average Hsp 60 concentration was 147.4 microg/mg protein. Mercury levels in muscle tissue in these fish averaged 0.382 ppm. Using a subset of samples (n = 24), we determined that the major component in the muscle of Alaskan subsistence fish was methyl mercury. No correlation was observed between Hsp 60 or Hsp 70 expression in gill tissue and mercury concentrations in muscle tissue. Hsp 60 and Hsp 70 protein levels in the gills were correlated. PMID:10622434

Duffy, L K; Scofield, E; Rodgers, T; Patton, M; Bowyer, R T

1999-10-01

355

GEMAS: Mercury in European agricultural and grazing land soils - sources and environmental risk  

NASA Astrophysics Data System (ADS)

Agricultural (Ap, Ap-horizon, 0-20 cm) and grasing land soil samples (Gr, 0-10 cm) were collected from a large part of Europe (33 countries, 5.6 million km2) at an average density of 1 sample site/2500 km2. The resulting more than 2 x 2000 soil samples were air dried, sieved to <2 mm and analysed for their Hg concentrations following an aqua regia extraction. Median concentrations for Hg are 0.030 mg/kg (range: <0.003 - 1.56 mg/kg) for the Ap samples and 0.035 mg/kg (range:<0.003 - 3.12 mg/kg) for the Gr samples. Only 5 Ap and 10 Gr samples returned Hg concentrations above 0.5 mg/kg. In the geochemical maps the continental-scale distribution of the element is clearly dominated by geology. Climate plays also an important role, Hg accumulates in those areas of northern Europe where a wet and cold climate favors the build-up of organic material. Typical anthropogenic sources like coal fired power plants, chlor-alkaline factories, metal smelters and urban agglomerations are hardly visible at the continental scale but can have a major impact at the local scale.

Tore Ottesen, Rolf; Birke, Manfred; Gosar, Mateja; Reimann, Clemens

2014-05-01

356

Trace level voltammetric determination of heavy metals and total mercury in tea matrices (Camellia sinensis).  

PubMed

An analytical procedure regarding the voltammetric determination of mercury(II), copper(II), lead(II), cadmium(II) and zinc(II) by square wave anodic stripping voltammetry (SWASV) in matrices involved in food chain is proposed. In particular, tea leaves were analyzed as real samples. The digestion of each matrix was carried out using a concentrated HCl-HNO3-H2SO4 acidic attack mixture; 0.01 mol L(-1) EDTA-Na2+ 0.15 mol L(-1) NaCl + 0.5 mol L(-1) HCl was employed as the supporting electrolyte. The voltammetric measurements were carried out using a conventional three electrode cell, employing, as working electrodes, a gold electrode (GE) and a stationary hanging mercury drop electrode (HMDE). The analytical procedure has been verified on the standard reference materials Spinach Leaves NIST-SRM 1570a, Tomato Leaves NIST-SRM 1573a and Apple Leaves NIST-SRM 1515. For all the elements, the precision as repeatability, expressed as relative standard deviation (sr) was of the order of 3-5%, while the trueness, expressed as relative error (e) was of the order of 3-7%. Once set up on the standard reference materials, the analytical procedure was applied to commercial tea leaves samples. A critical comparison with spectroscopic measurements is also discussed. PMID:24416778

Melucci, Dora; Locatelli, Marcello; Locatelli, Clinio

2013-12-01

357

Mercury concentrations in breast feathers of three upper trophic level marine predators from the western Aleutian Islands, Alaska  

USGS Publications Warehouse

Mercury (Hg) is a toxic element distributed globally through atmospheric transport. Agattu Island, located in the western Aleutian Islands, Alaska, has no history of point-sources of Hg contamination. We provide baseline levels of total mercury (THg) concentrations in breast feathers of three birds that breed on the island. Geometric mean THg concentrations in feathers of fork-tailed storm-petrels (Oceanodroma furcata; 6703 ± 1635, ng/g fresh weight [fw]) were higher than all other species, including snowy owl (Bubo scandiacus; 2105 ± 1631, ng/g fw), a raptor with a diet composed largely of storm-petrels at Agattu Island. There were no significant differences in mean THg concentrations of breast feathers among adult Kittlitz’s murrelet (Brachyramphus brevirostris; 1658 ± 1276, ng/g fw) and chicks (1475 ± 671, ng/g fw) and snowy owls. The observed THg concentrations in fork-tailed storm-petrel feathers emphasizes the need for further study of Hg pollution in the western Aleutian Islands.

Kaler, Robb S. A.; Kenney, Leah A.; Bond, Alexander L.; Eagles-Smith, Collin A.

2014-01-01

358

Progress and Future Plans for Mercury Remediation at the Y-12 National Security Complex, Oak Ridge, Tennessee - 13059  

SciTech Connect

The U.S. Department of Energy (DOE), along with the Tennessee Department of Environment and Conservation (TDEC) and the U.S. Environmental Protection Agency (EPA), has identified mercury contamination at the Y-12 National Security Complex (Y-12) as the highest priority cleanup risk on the Oak Ridge Reservation (ORR). The historic loss of mercury to the environment dwarfs any other contaminant release on the ORR. Efforts over the last 20 years to reduce mercury levels leaving the site in the surface waters of Upper East Fork Poplar Creek (UEFPC) have not resulted in a corresponding decrease in mercury concentrations in fish. Further reductions in mercury surface water concentrations are needed. Recent stimulus funding through the American Recovery and Reinvestment Act of 2009 (ARRA) has supported several major efforts involving mercury cleanup at Y-12. Near-term implementation activities are being pursued with remaining funds and include design of a centrally located mercury treatment facility for waterborne mercury, treatability studies on mercury-contaminated soils, and free mercury removal from storm drains. Out-year source removal will entail demolition/disposal of several massive uranium processing facilities along with removal and disposal of underlying contaminated soil. As a National Priorities List (NPL) site, cleanup is implemented under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and directed by the Federal Facility Agreement (FFA) between DOE, EPA, and TDEC. The CERCLA process is followed to plan, reach approval, implement, and monitor the cleanup. (authors)

Wilkerson, Laura O. [DOE Oak Ridge, P.O. Box 2001, Oak Ridge, TN 37831 (United States)] [DOE Oak Ridge, P.O. Box 2001, Oak Ridge, TN 37831 (United States); DePaoli, Susan M. [Pro2Serve, 1100 Bethel Valley Rd., Oak Ridge, TN 37830 (United States)] [Pro2Serve, 1100 Bethel Valley Rd., Oak Ridge, TN 37830 (United States); Turner, Ralph [P.O. Box 421, Squamish, BC V8B 0A4 (United States)] [P.O. Box 421, Squamish, BC V8B 0A4 (United States)

2013-07-01

359

TRANSPORT OF LOW-LEVEL RADIOACTIVE SOIL AT DEEP-OCEAN DISPOSAL SITE  

EPA Science Inventory

Transport studies were conducted to assess ocean disposal of soil contaminated with low-level natural radioisotopes. he experimental approach involved characterization of the soil for parameters affecting transport and fate of radionuclides- Radioactivity was associated with disc...

360

Arsenic, cadmium, chromium, lead, mercury, and selenium levels in blood of four species of turtles from the Amazon in Brazil.  

PubMed

Using blood as a method of assessing metal levels in turtles may be useful for populations that are threatened or endangered or are decreasing. In this study the levels of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and selenium (Se) in blood of four species of turtles from the tributaries of the Rio Negro in the Amazon of Brazil were examined. The turtles included the six-tubercled Amazon (river) turtle (Podocnemis sextuberculata), red-headed Amazon (river) turtle (Podocnemis erythrocephala), big-headed Amazon (river) turtle (Peltocephalus dumerilianus), and matamata turtle (Chelus fimbriatus). Blood samples were taken from the vein in the left hind leg of each turtle. There were significant interspecific differences in the sizes of the turtles from the Rio Negro, and in concentrations of Pb, Hg, and Se; the smallest species (red-headed turtles) had the highest levels of Pb in their blood, while Se levels were highest in big-headed turtles and lowest in red-headed turtles. Hg in blood was highest in matamata, intermediate in big-headed, and lowest in the other two turtles. Even though females were significantly larger than males, there were no significant differences in metal levels as a function of gender, and the only relationship of metals to size was for Cd. Variations in metal levels among species suggest that blood may be a useful bioindicator. Metal levels were not high enough to pose a health risk to the turtles or to consumers, such as humans. PMID:19953418

Burger, Joanna; Jeitner, Christian; Schneider, Larissa; Vogt, Richard; Gochfeld, Michael

2010-01-01

361

Levels and temporal trends (1983-2003) of persistent organic pollutants (POPs) and mercury (Hg) in seabird eggs from Northern Norway.  

PubMed

The main objective of this study was to investigate possible temporal trends of persistent organic pollutants (POPs) and mercury in eggs of herring gulls (Larus argentatus), black-legged kittiwakes (Rissa tridactyla), common guillemots (Uria aalge) and Atlantic puffins (Fratercula arctica) in Northern Norway. Eggs were collected in 1983, 1993 and 2003. Egg concentrations of POPs (PCB congeners IUPAC numbers: CB-28, 74, 66, 101, 99, 110, 149, 118, 153, 105, 141, 138, 187, 128, 156, 157, 180, 170, 194, 206, HCB, alpha-HCH, beta-HCH, gamma-HCH, oxychlordane, trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT) and mercury were quantified. Generally, POP levels decreased between 1983 and 2003 in all species. No significant temporal trend in mercury levels was found between 1983 and 2003. PMID:18262696

Helgason, Lisa B; Barrett, Rob; Lie, Elisabeth; Polder, Anuschka; Skaare, Janneche U; Gabrielsen, Geir W

2008-09-01

362

Short title: Iron oxide and mercury biogeochemistry in tropical soils1 General research paper3  

E-print Network

since the beginning7 of the gold rush towards the end of the 19th century (Nriagu, 1994).8 In pristine activities, and in particular gold mining,5 have contributed to raising the levels of Hg in these regions

363

Environmental Geochemistry of Mercury Mines in Alaska  

NSDL National Science Digital Library

This U.S. Geological Survey fact sheet investigates potential environmental contamination around naturally occurring, mercury-rich mineral deposits in Alaska. Testing of mercury levels in streams and sediments is described, as well as mercury levels in fish downstream from mines and the environmental effects of mercury entering the food chain.

364

The effect of soil moisture levels on evapotranspiration from cotton and grain sorghum  

E-print Network

OF TABLES Table Page The Coefficients, c and K, Calculated for Sampling Intervals with No Rainfall Using Both Exponential and Uniform Soil Moisture Depletion. . . . . . . . . . 22 II . Data for the Regression of Soil Moisture and Pan Evaporation... on the Coefficients, c and K 24 III . Correlation Coefficients and Their Probability Levels for the Correlation Between the Soil Moisture Accretion and tl-. e Uniform Daily Soil Moisture Depletion 44 Correlaticn Coeffictents and Their Probability Levels...

Schneider, Arland David

2012-06-07

365

ECOLOGICAL SOIL SCREENING LEVELS (ECO-SSLS) FOR SUPERFUND  

EPA Science Inventory

The US Environmental Protection Agency (USEPA) has established ecological soil screening values for 24 soil contaminants frequently of ecological concern for terrestrial plants and animals at hazardous waste sites. The Eco-SSL derivation process represents the collaborative effor...

366

Mercury levels in muscle of six species of turtles eaten by people along the Rio Negro of the Amazon basin.  

PubMed

Mercury levels in the Amazon River are generally high, but there are no published studies on Hg levels in turtles from the region. In this study, levels of Hg were examined in the muscle of six species of turtles in the Rio Negro in the Amazon basin of Brazil, including Podocnemis unifilis, Podocnemis expansa, Podocnemis erythrocephala, Podocnemis sextuberculata, Peltocephalus dumerilianus, and Chelus fimbriatus. It is important to analyze Hg levels in chelonians in this region because of the potential health risk to humans and other receptors that eat them, as well as their potential use as bioindicators. The effect of sex, weight, and carapace length on Hg concentrations in turtle muscle was examined to determine if the levels represent a health risk to riverine people. There was a significant interspecific difference in Hg levels but no differences as a function of size or gender. The highest Hg level was found in Chelus fimbriatus (mean = 432 ppb, standard deviation +/- 196 ppb), followed by Peltocephalus dumerilianus (106 +/- 41 ppb), Podocnemis expansa (62 +/- 49 ppb), P. sextuberculata (61 +/- 40 ppb), P. unilifis (35 +/- 17 ppb), and P. erythrocephala (33.1 +/- 17 ppb). Of the species studied, the piscivorous C. fimbriatus had the highest Hg level. Hg levels in turtles were similar to the levels found in fish from the same basin. Levels of Hg in the muscle of C. fimbriatus are sufficiently high to pose a potential risk to humans who consume them. This study represents the first comparative study of Hg levels in muscle of six species of turtles. PMID:19621205

Schneider, Larissa; Belger, Lauren; Burger, Joanna; Vogt, Richard C; Ferrara, Camila R

2010-02-01

367

The impact of a low humus level in arable soils on microbial properties, soil organic matter quality and crop yield  

Microsoft Academic Search

In arable soils in Schleswig-Holstein (Northwest Germany) nearly 30% of the total organic C (TOC) stored in former times\\u000a in the soil has been mineralized in the last 20 years. Microbial biomass, enzyme activities and the soil organic matter (SOM)\\u000a composition were investigated in order to elucidate if a low TOC level affects microbial parameters, SOM quality and crop\\u000a yield.

L. Beyer; K. Sieling; K. Pingpank

1999-01-01

368

LOCAL IMPACTS OF MERCURY EMISSIONS FROM COAL FIRED POWER PLANTS.  

SciTech Connect

Mercury is a neurotoxin that accumulates in the food chain and is therefore a health concern. The primary human exposure pathway is through fish consumption. Coal-fired power plants emit mercury and there is uncertainty over whether this creates localized hot spots of mercury leading to substantially higher levels of mercury in water bodies and therefore higher exposure. To obtain direct evidence of local deposition patterns, soil and vegetations samples from around three U.S. coal-fired power plants were collected and analyzed for evidence of hot spots and for correlation with model predictions of deposition. At all three sites, there was no correlation between modeled mercury deposition and either soil concentrations or vegetation concentrations. It was estimated that less than 2% of the total mercury emissions from these plants deposited within 15 km of these plants. These small percentages of deposition are consistent with the literature review findings of only minor perturbations in environmental levels, as opposed to hot spots, near the plants. The major objective of the sampling studies was to determine if there was evidence for hot spots of mercury deposition around coal-fired power plants. From a public health perspective, such a hot spot must be large enough to insure that it did not occur by chance, and it must increase mercury concentrations to a level in which health effects are a concern in a water body large enough to support a population of subsistence fishers. The results of this study suggest that neither of these conditions has been met.

SULLIVAN, T.M.; BOWERMAN, B.; ADAMS, J.; MILIAN, L.; LIPFERT, F.; SUBRAMANIAM, S.; BLAKE, R.

2005-09-21

369

Does shift in oxygen level in soil air affect the trace gases emissions?  

NASA Astrophysics Data System (ADS)

Biogenic processes in soil such as, trace gasses emissions are influenced by presence or absence of oxygen as it is a dominant final acceptor of electrons for number of biochemical processes. However, it is unknown that trace gases emissions from soil are influenced by the level of oxygen or not. To understand the impact of oxygen level on CO2, CH4 and N2O emissions, five contrasting soils which differ in land use and other properties, were incubated at constant temperature and moisture in an automated chamber measurement system. Automated system continuously (30 mL/min) flushed the chambers holding soil samples with inlet air of known composition and the outlet air, sampling the headspace of the column, was connected to an automated multiport stream selection valve (Valco) that directed the air stream from different columns sequentially to instrumental part (LiCOR6262,PICARRO2101i and PICCARO2301). Other greenhouse gases and isotopes (?13C & D) of CH4 were sampled weekly using 2L flasks. Oxygen levels in inlet air were switched weekly, started from 20% followed by 10, 5, 2.5, 1, 0%, and all levels were repeated in reverse fashion (from 1 to 20%).The results showed that soil respiration was higher in soils that were rich in soil organic matter with higher microbial biomass. Three out of five soils exhibited a gradual decrease in soil respiration while shifting higher to lower O2 levels but no such impact was recorded during gradual increase in O2 level. The lowest respiration rates in all soil types were recorded under anaerobic conditions. Forest soils were rich in soil organic carbon and respired more CO2 than grassland or cropland soils. All soils oxidized CH4, except one grassland soil which was acidic in nature (pH=4.1), in the presence of O2 at all levels. Amount of CH4 oxidized varied among soil types and was highest in forest soils. Under anaerobic condition CH4 oxidation was not observed in any soil, while two soils (cropland and one grassland) emitted methane but at very low concentrations. Large amount of N2O emissions were recorded under 0% O2 level, and the amount of N2O emitted was higher in forest soils than grassland soils. In conclusion, the variable impact of oxygen levels on trace gases emissions depends on soil and trace gas type.

malghani, S.; Gleixner, G.; Trumbore, S.

2013-12-01

370

Overview of investigations into mercury in ground water, soils, and septage, new jersey coastal plain  

Microsoft Academic Search

Since the early 1980s, investigations by health departments of eight counties in southern New Jersey, by the NJ Department of Environmental Protection (NJDEP), and subsequently by the US Geological Survey (USGS), have shown that Hg concentrations in water tapped by about 600 domestic wells exceed the maximum contaminant level (MCL) of 2 ?g\\/L. The wells are finished in the areally

Julia L. Barringer; Zoltan Szabo

2006-01-01

371

Changes in brain monoamine levels and monoamine oxidase activity in the catfish, Clarias batrachus, during chronic treatments with mercurials  

SciTech Connect

In mammals, the central nervous system is the primary target for CH{sub 3}Hg poisoning which is clinically known as Minamata disease. Hg is a widely recognized neurotoxin and has been reported to impair brain monoamine neurotransmitter metabolism. Reports on effects of Hg on brain monoamine activity in fishes are scarce. In the present study, therefore, changes in the brain monoamine levels and the degradation enzyme, monoamine oxidase (MAO), are described in the catfish, Clarias batrachus, exposed to sublethal concentrations of mercuric chloride (HgCl{sub 2}-inorganic Hg), methylmercuric chloride (CH{sub 3}HgCl-organic Hg), and a commercial mercurial fungicide formulation, emisan 6 (methoxyethyl Hg-organic Hg) for 45, 90 and 180 d during gonadal recrudescence. These intervals correspond to late preparatory, prespawning and spawning phases, respectively, of the annual reproductive cycle of the catfish.

Kirubagaran, R.; Joy, K.P. (Banaras Hindu Univ., Varanasi (India))

1990-07-01

372

MERCURY IN MARINE LIFE DATABASE  

EPA Science Inventory

The purpose of the Mercury in Marine Life Project is to organize information on estuarine and marine species so that EPA can better understand both the extent of monitoring for mercury and level of mercury contamination in the biota of coastal environments. This report follows a ...

373

ATMOSPHERIC MERCURY TRANSPORT AND DEPOSITION  

EPA Science Inventory

The current state of our scientific understanding the mercury cycle tells us that most of the mercury getting into fish comes from atmospheric deposition, but methylation of that mercury in aquatic systems is required for the concentrations in fish to reach harmful levels. We st...

374

Contamination assessment of mercury and arsenic in roadway dust from Baoji, China  

NASA Astrophysics Data System (ADS)

The physicochemical properties and the contamination levels of mercury and arsenic in roadway dust from Baoji, NW China were investigated using an Atomic Fluorescence Spectrophotometer. Contamination levels were assessed based on the geoaccumulation index and the enrichment factor. The results show that magnetic susceptibilities of roadway dust were higher than Holocene loess-soil of central Shaanxi Loess Plateau. The mean contents of organic matter, PM10 and PM100 were 8.8%, 21.8% and 98.6%, respectively. Mercury concentration ranged from 0.48 to 2.32 ?g g -1, with a mean value of 1.11 ?g g -1, 17.1 times the Chinese soil mercury background value and 37 times the Shaanxi soil mercury background value. Arsenic concentration ranged from 9.0 to 42.8 ?g g -1, with a mean value of 19.8 ?g g -1, 1.8 times the Chinese and Shaanxi soil arsenic background values. The geoaccumlation index and enrichment factor indicate that mercury in the dust mainly originated from anthropogenic sources with ratings of "strongly polluted" and "strongly to extremely polluted", whereas arsenic in dust originated from both natural and anthropogenic sources, with a ratings of "moderately to strongly polluted" and "strongly polluted". Industrial activities, such as a coal-fired power station, coke-oven plant, and cement manufacturing plant, augmented by vehicular traffic, are the anthropogenic sources of mercury and arsenic in the roadway dust.

Lu, Xinwei; Li, Loretta Y.; Wang, Lijun; Lei, Kai; Huang, Jing; Zhai, Yuxiang

375

Impact of Soil Properties on Critical Concentrations of Cadmium, Lead, Copper, Zinc, and Mercury in Soil and Soil Solution in View of Ecotoxicological Effects  

Microsoft Academic Search

Concern about the input of metals to terrestrial ecosystems is related to (i) the ecotoxicological impact on soil organisms\\u000a and plants (Bringmark et al. 1998; Palmborg et al. 1998) and also on aquatic organisms resulting from runoff to surface water and (ii) the uptake via food chains into animal tissues\\u000a and products, which may result in health effects on animals

Wim de Vries; Steve Lofts; Ed Tipping; Markus Meili; Jan E. Groenenberg; Gudrun Schütze

2007-01-01

376

Soil trampling in an Antarctic Specially Protected Area: tools to assess levels of human impact  

E-print Network

Soil trampling in an Antarctic Specially Protected Area: tools to assess levels of human impact P of current advice relating to travel on foot over Antarctic vegetation-free soils. These are based to alter both physical and biological characteristics of Byers Peninsula soils, although at the lowest

Justel Eusebio, Ana

377

Effect of high ammonium levels on nitrification, soil acidification, and exchangeable cation dynamics  

Microsoft Academic Search

In almond orchards which are fertilized and irrigated with drip systems, fertilizers are applied to a relatively small soil volumes several times during the growing season. Where NH4?based fertilizers are used, high NH4 levels are anticipated in soil solution and on exchange sites. The effects of high NH4 concentration on nitrification, soil acidification, and exchangeable cation dynamics were studied in

Robert J. Zasoski

1993-01-01

378

A field study on factors influencing Cd levels in soils and in grain of oats and winter wheat  

Microsoft Academic Search

The influence of selected factors on Cd levels in soils and in grain of oats and winter wheat was investigated. Soil and grain were sampled at sites randomly distributed over Sweden. Organic soils generally had higher Cd contents and lower pH levels than mineral soils, and plants growing in organic soils tended to have higher Cd contents than plants growing

Jan E. Eriksson

1990-01-01

379

Growth of three species of Bidens under different levels of soil moisture content  

Microsoft Academic Search

By the assumption that both soil moisture and soil air affect plant growth as linear factor, the relationship between mean\\u000a plant dry weight and soil moisture content was newly formulated. Its applicability to actual growth data was tested by growing\\u000a three species ofBidens under different levels of soil moisture content. The growth data ofBidens well satisfied the new formula. The

Kiyokazu Suehiro; Kazuo Hozumi; Kichiro Shinozaki

1984-01-01

380

Temporal trends (1989-2011) in levels of mercury and other heavy metals in feathers of fledgling great egrets nesting in Barnegat Bay, NJ.  

PubMed

There is an abundance of data for levels of metals from a range of species, but relatively few long-term time series from the same location. In this paper I examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from fledgling great egrets (Ardea alba) collected at nesting colonies in Barnegat Bay, New Jersey from 1989 to 2011. The primary objectives were to test the null hypotheses that (1) There were no temporal differences in metal levels in feathers of fledgling great egrets, and (2) Great egrets nesting in different areas of Barnegat Bay (New Jersey) did not differ in metal levels. There were significant yearly variations in levels of all heavy metals in feathers of fledgling great egret, but levels decreased significantly from 1989 to 2011 only for lead (1,470 ppb to 54.3 ppb), cadmium (277 ppb to 30.5 ppb), and manganese (only since 1996; 2,669 ppb to 329 ppb)). Although mercury levels decreased from 2003-2008 (6,430 ppb to 1,042 ppb), there was no pattern before 2003, and levels increased after 2008 to 2,610 ppb in 2011. Lead, cadmium, chromium, manganese and mercury were higher in feathers from great egrets nesting in the northern part of the bay, and selenium was highest in feathers from mid-bay. The lack of a temporal decline in mercury levels in feathers of great egrets is cause for concern, since the high levels in feathers from some years (means as high as 6,430 ppb) are in the range associated with adverse effects (5,000 ppb for feathers). PMID:23434313

Burger, Joanna

2013-04-01