Fate of mercury in a terrestrial biological lab process using Polypogon monspeliensis and Cyperus odoratus

Abstract

Mercury has been extracted in Queretaro, Mexico since the 1960s. The mining wastes were open-air disposal and these mercury wastes have polluted the zone. The aim of this research was to evaluate mercury's fate in lab scale terrestrial reactors considering the following mercury species: soluble, interchangeable, strongly bound, organic, and residual ones. Soils were sampled in two former mines of Pinal de Amoles, Queretaro, Mexico (N 20° 58′ to 21° 21′ and West 99° 26′ to 99° 43′) with initial mercury concentrations were 424?±?29 and 433?±?12?mg?kg^?1 for “La Lorena” and “San Jose” former mines, respectively. Two vegetal species Polypogon monspeliensis and Cyperus odoratus were used and 20 reactors were constructed for the lab process. Total mercury was removed to 49–79% from both soils. Mercury elemental, exchangeable, and organic species had the most removal or exchange in the process. Metal uptake, by the plants, was of 5–6% for P. monspeliensis and 5–15% for C. odoratus. Also, mercury fate was estimated to the atmosphere to be 3.3–4.5?mg m^?2 h^?1 for both soils.     

Accumulation of arsenic and heavy metals in some Viola species from an abandoned mine,Alchar, Republic of Macedonia (FYROM)

Abstract

The uptake and distribution of arsenic (As) and some heavy metals was determined in three Viola endemic species from As‐overloaded soil in an abandoned mine at Alchar, Republic of Macedonia (FYROM – The Former Yugoslav Republic of Macedonia). Some essential elements were also analyzed in order to characterize the common geochemical properties of this site. Total As content in soil ranged from 3347 to 14,467 mg kg^?1, and plant available As from 23 to 1589 mg kg^?1. The concentration of As in roots ranged from 783 mg kg^?1 in Viola macedonica to 2124 mg kg^?1 in Viola arsenica. Only a small amount of As accumulated in the aboveground parts of these species (<100 mg kg^?1), while in shoots of Viola allchariensis, As accumulated in the range 187–439 mg kg^?1. Arsenic accumulation in the roots of these Viola species may make these plants valuable tools for the bioindication and phytoremediation (phytostabilization) of As in naturally loaded and anthropogenically contaminated soils.     

Contribution to the occurrence and former distribution of Tephroseris palustris (Compositae) in the Central Europe

Tephroseris palustris (syn. Senecio palustris) is a circumboreal species with large distribution range. The European part of the recent distribution area extends southwards to central France, Germany, Poland, and Ukraine, while in Great Britain, Czech Republic, Hungary, Slovakia, and Romania, T. palustris has been treated as extinct species. The southern boundary of its distribution in Poland does not reach the Carpathian territory. Herbarium specimens, formerly collected in Czech Republic, were found, however, all Czech localities are extinct. No herbarium specimens confirming the old literature data from Slovakia, Hungary, and Romania have been found. Some herbarium specimens coming from this area, and declared as T. palustris (S. palustris), in fact, refer to Senecio paludosus L. Contrary to previous nomenclature review (Jeffrey & Chen 1984), the name Tephroseris palustris (L.) Rchb. seems to be correct (Reichenbach Fl. Saxon.: 146, 1842).     

Using Earthworms to Assess Hg Distribution and Bioavailability in Gold Mining Soils

Between 1980 and 2000, the municipality of Cachoeira do Piriá, located in Pará State, Brazil, experienced an intense gold rush with approximately 5,000 artisanal miners discharging more than four tonnes of mercury into soils, air and aquatic systems. Mercury is dispersed across an area of approximately 2,100 ha and concentrations in soils and sediments frequently exceed 1,000 μg.kg^?1. The metallic mercury discharged by miners into the environment has the potential to be transformed into a highly toxic form of mercury, methylmercury. A 28-day bioassay with the earthworm Eisenia fetida was used to assess mercury bioavailability in mine tailings, soils, and sediments. Experiments indicated that the highest Hg concentration in earthworms was associated with low-Hg-organic-rich soils collected from densely vegetated areas despite higher mercury concentrations in organic-poor tailings. This indicates that reaction with organic acids is an important pathway for mercury incorporation into food chains. The quick, inexpensive, and simple bioassay also provided a means to evaluate remedial measures (i.e. by capping “hotspots” with local soils). Earthworm experiments indicate that covering “environmental hotspots” (sites with high Hg bioavailability) with local clay-rich sediments is very effective in terms of preventing uptake of mercury from tailings, while organic-rich sediments are relatively ineffective.     

Phytoremediation potential of some agricultural plants on heavy metal contaminated mine waste soils,salem district,tamilnadu

The Pot culture experiment performed for phytoextraction potential of selected agricultural plants [millet (Eleusine coracana), mustard (Brassica juncea), jowar (Sorghum bicolor), black gram (Vigna mungo), pumpkin (Telfairia occidentalis)] grown in metal contaminated soils around the Salem region, Tamilnadu, India. Physiochemical characterization of soils, reported as low to medium level of N, P, K was found in test soils. The Cr content higher in mine soils than control and the values are 0.176 mg/L in Dalmia soil and 0.049 mg/L in Burn &; Co soil. The germination rate low in mine soil than control soils (25 to 85%). The content of chlorophyll, carotenoid, carbohydrate and protein decreased in mine soils than control. The morphological parameters and biomass values decreased in experimental plants due to metal accumulation. Proline content increased in test plants and ranged from 0.113 mg g^?1 to 0.858 mg g^?1 which indicate the stress condition due to toxicity of metals. Sorghum and black gram plants reported as metal tolerant capacity. Among the plants, Sorghum produced good results (both biomass and biochemical parameters) which equal to control plant and suggests Sorghum plant is an ideal for remediation of metal contaminated soils.     

Relationship Between Localization of Gold Mining Areas and Hair Mercury Levels in People from Bolivar, North of Colombia

Mercury (Hg) is a heavy metal that, once in the environment, is bioaccumulated and biomagnified through food chain impacting ecosystems. The aim of this study was to evaluate total Hg (T-Hg) concentrations in individuals along Cauca and Magdalena Rivers in Colombia, where most gold mining activities take place. A total of 1,328 hair samples were collected and analyzed for T-Hg using atomic absorption spectroscopy. T-Hg concentrations ranged from 0.01 to 20.14?μg/g. Greatest levels were detected in La Raya (5.27?±?0.32?μg/g), Achi (2.44?±?0.22?μg/g), and Montecristo (2.20?±?0.20?μg/g), places that are located near gold mines. Concentrations decreased with the distance from main mining areas. Only 0.75% of the individuals had T-Hg levels above 10?μg/g. Men had significantly higher T-Hg levels than women, and correlation analysis revealed moderately weak but significant relationships between T-Hg and weight (R?=?0.111, P?相似文献   

Heavy-Metal Phytostabilizing Potential of Agrostis castellana Boiss. & Reuter

The soils of many abandoned mine sites in the central region of Spain are heavily polluted with a number of different metals. Having frequently found Agrostis castellana growing at these old mine sites, this study was designed to assess its remediation capacity for this type of setting. In an initial field study, plant specimens were collected from 4 abandoned mine sites to determine pollutant concentrations in their roots and shoots. This was followed by a 4-year bioassay in a controlled environment in which soils collected from the mines were used to set up microcosms. Maximum root concentrations of the most polluting elements present in the bioassay were 3625 mg kg^?1 Zn, 2793 mg kg^?1 Cu, 13042 mg kg^?1 Pb, 49 mg kg^?1 Cd and 957 mg kg^?1 As. These concentrations represent root bioaccumulation indices of over 1 and usually >2. In contrast, indices of transfer to above-ground phytomass were always < 1, indicating this species is a good candidate for use as a phytostabilizer. However, the high metal concentrations that could reach the above-ground mass of this plant determines a need for close monitoring and avoiding the use of areas under restoration for hunting or grazing.     

Chemical characteristics of soils and pore waters of three wetland sites dominated by Phragmites australis: relation to vegetation composition and reed performance

Chemical characteristics of soils and soil pore waters, plant species composition and horizontal stand structure were investigated for three reed stands in the Třeboň Basin (Czech Republic): Branná sand pit and two littoral stands of Rožmberk fishpond (Rožmberk East and Rožmberk West). Phragmites stands were expanding, stable and retreating at the three sites, respectively. The elemental soil composition (especially of C, N, P, and K) indicated the lowest trophic conditions at Branná, intermediate at Rožmberk East and the highest at Rožmberk West. This corresponded well also with concentrations of ammonium nitrogen, dissolved reactive phosphate and total phosphorus in the soil pore water. In contrast, Branná had by far the highest level of total nitrogen, determined by nitrate nitrogen (20 mg l⁻¹), and the highest level of total dissolved solids (concentrations of NO₃⁻, SO₄²⁻, Ca²⁺ and Mg²⁺) of all three sites. No conspicuous differences were found among the three stands in biomass and its allocation. The vegetation composition corresponded more closely to elemental soil composition than to total nitrogen or total dissolved solids in the pore water. It is concluded that Branná provides an example of a site subjected to an initiating but dramatic and fast eutrophication while conditions at the two Rožmberk sites indicate a slower but longer lasting eutrophication. Owing to continuous heavy organic loading, Rožmberk West represents a hypertrophic site characterised by the highest levels of organic matter and associated characteristics (soil C, N, P, K, dissolved P), but also by the most severe lack of oxygen of the three sites.     

PHYTOEXTRACTION OF METAL POLLUTED SOILS AROUND A Pb-Zn MINE BY CROP PLANTS

In order to assess their practical capability for the absorption and accumulation of Pb, Zn, and Cu, five common crop plants, i.e. maize (Zea mays), sunflower (Helianthus annuus), canola (Brassica napus), barley (Hordeum vulgare) and White lupine (Lupinus albus) were tested in pot experiments using six soil samples taken from mine tailings, pasture and arable soils around an old Pb-Zn mine in Spain. Metal concentration ranges of the soils were 76.2–785 mg kg^?1, 127–1652 mg kg^?1, and 12.4–82.6 mg kg^?1 for Zn, Pb, and Cu, respectively. With the exception of the highest polluted sample, soil total metal concentration did not influence significantly biomass yields of each crop for the different growth substrates. The order found for the total metal accumulation rate (TMAR) in the crops was Zn>>Pb > Cu, with maize reaching the highest metal concentrations. Pb root concentrations were markedly higher than those of shoots for all the crops, while Zn and Cu were translocated to shoots more efficiently. Concentrations of metals extracted by EDTA and BCR sequential extraction were well correlated, in general, with both root metal content and TMAR. CaCl₂-extracted Zn was well correlated with root concentrations, TMAR and, in some cases, with shoot contents. Our study showed that the test crops were not feasible to remediate the heavily or moderately contaminated soils studied here in order to achieve the total metal soil concentrations required by the current European laws.     

X-ray Fluorescence (XRF) Analysis of Soil Heavy Metal Pollution from an Industrial Area in Kumasi,Ghana

Knowledge of soil heavy metal concentration is very important for assessing the purity and quality of the soil in an environment. The concentrations of nine heavy metals (NHM), Zn, Pb, Cr, Cu, Co, Ni, Cd, Hg, and As, from the near-surface soils (～ 0–15 cm) from an industrial cluster in Kumasi, Ghana, were qualitatively and quantitatively measured and analyzed using X-ray fluorescence (XRF) spectroscopy analysis. The sources of these NHM were mainly anthropogenic as a result of the indiscriminate industrial waste disposal. In all, a total of about 100 soil samples were taken from six sampling sites, four of which were industrial and the remaining two residential. Forty soil samples out of the total number were carefully selected for elemental analyses and the mean heavy metal concentrations were calculated using statistical methods. The results from locations of high industrial impact showed that the mean concentrations of the NHM present in the soil were in the order of Zn (189.2?908.6 mgkg^?1), Pb (133.7?571.3 mgkg^?1), Cr (91.3?545.8 mgkg^?1), Cu (62.9?334.6 mgkg^?1), Co (38.6?81.9 mgkg^?1), Ni (12.4?30.9 mgkg^?1), Cd (6.9?13.2 mgkg^?1), Hg (5.5?10.4 mg kg^?1), and As (2.3?18.6 mgkg^?1). Apart from Ni and As, all the heavy metals recorded concentrations that ranged from 10?900% higher than their respective threshold limit values (TLVs). Heavy metal concentrations from the residential sites were comparatively far lower with only Cr, Cd, and Hg registering concentrations between 65?250% above their TLVs. The cluster with its residential communities is at a serious risk of soil heavy metal toxicity and awareness to this needs to be created as such.     

Heavy metal impact on bacterial biomass based on DNA analyses and uptake by wild plants in the abandoned copper mine soils

The metals contamination in surface soils and their accumulation in wild plants from the abandoned Burra and Kapunda copper mines located in South Australia were assessed, and the predominant bacterial diversity in the contaminated surface soils from these two abandoned copper mine sites were evaluated through polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) analysis. The results showed the average concentration of Cu in soils was 3821.59 mg/kg while wild plants accumulated up to 173.44 mg/kg. The concentration of Cu in shoots of spear grass (Stipa uitida) and berry saltbush (Afriplex semibaccata) was higher than that of roots. The concentration of total and extractable As, Cd, Cu and Pb in soils slightly correlated with of these elements in the corresponding wild plants. The toxicity of Cu in heavily contaminated soils impacted on the quantities of specific microbial populations and no significant change in the microbial diversity of highly contaminated soils.     

Hair Mercury Concentrations of Lactating Mothers and Breastfed Infants in Iran (Fish Consumption and Mercury Exposure)

Coastal populations with high seafood consumption in the South Caspian Sea (Iran) have a significant exposure to dietary mercury. This study assesses the biomonitoring of mercury in mothers and breastfed infants in the South Caspian Sea. The mean of mercury concentration in the hair of 93 pairs of mothers and infants was obtained and was 3.55 and 1.89???g?g^?1, respectively. A statistically significant correlation (R?=?0.850, P?=?0.000) was seen between mercury concentration in the hair of mothers and infants. The results of this study indicate that hair mercury concentrations exceeded the USEPA reference dose of 1???g?g^?1 in 82.7?% of mothers and 61.2?% of infants. Also, 31?% of the mothers and 10.7?% of the infants had mercury concentrations more than the WHO ??threshold?? level (5???g?g^?1). The age and fish consumption of mothers were the factors that significantly affected the hair mercury concentration of mothers and infants. Number of dental amalgam fillings of mothers was the factor that only affected mercury in the hair of mothers. According to the results, we can conclude that the main determinant of mercury exposure was the intake of mercury through fish consumption of mothers.     

Radiocesium in mushrooms from selected locations in the Czech Republic and the Slovak Republic

In this paper, activity concentrations of radiocesium in mushrooms from various locations in the Czech Republic and the Slovak Republic in the years 2000–2004 are presented. Summary reports of Czech regulatory bodies have judged the average activity concentrations in mushrooms to be remarkably below the maximum permissible level of contamination. However, there are certain regions where radiocesium activities have approached the maximum permissible level for contamination of basic foodstuff. For example, the highest activity concentration of ¹³⁷Cs measured by gamma-spectrometry was 2,263 Bq kg⁻¹ (on a dry mass basis), in Xerocomus badius from Staré Ransko (a locality in the Czech-Moravian Highlands, Czech Republic). The highest activity concentration of ¹³⁷Cs measured in Slovakia was 966 Bq kg⁻¹ (on a dry mass basis), for Suillus luteus from Senica. For comparison, the corresponding activity concentration in a sample taken within the 30 km zone around Chernobyl was measured to be 6,000 Bq kg⁻¹ (on a dry mass basis). Our results have also demonstrated remarkably lower activity concentrations of ¹³⁷Cs in Slovakia compared to those in the Czech Republic.     

Terrestrial organic matter biomarkers as tracers of Hg sources in lake sediments

Terrestrial organic matter (TOM) plays a key role in mercury (Hg) dynamics between watersheds and lakes. In this study we attempts to determine the role of TOM source and quality and not only quantity, in the fate and transport of total Hg (T-Hg) to boreal lakes. Integrating the watershed complexity is a daunting task. Within the scope of this project, we characterized this organic matter at a molecular level in order to determine Hg transfer conditions to the sediments. We sampled ten lakes in the Quebec boreal forest. In each lake, we took a sediment core at the deepest point in addition to analyzing T-Hg and a set of terrigenous biomarkers in recent sediments. Our results show no relationship between TOM quantity and T-Hg concentration in lake sediments. However, [T-Hg] variation is well explained by the increase of 3,5Bd/V ratios (R²?=?0.84; p?<?0.0002) and the decrease of C/V ratios (R²?=?0.5; p?<?0.0227). Our study shows that TOM source and quality are determinant for Hg loadings in lake sediments. More precisely, increasing TOM derived from humified soil horizons explains most of Hg level variation within sediments.     

Gaseous Elemental Mercury (GEM) Emissions from Snow Surfaces in Northern New York

Snow surface-to-air exchange of gaseous elemental mercury (GEM) was measured using a modified Teflon fluorinated ethylene propylene (FEP) dynamic flux chamber (DFC) in a remote, open site in Potsdam, New York. Sampling was conducted during the winter months of 2011. The inlet and outlet of the DFC were coupled with a Tekran Model 2537A mercury (Hg) vapor analyzer using a Tekran Model 1110 two port synchronized sampler. The surface GEM flux ranged from −4.47 ng m⁻² hr⁻¹ to 9.89 ng m⁻² hr⁻¹. For most sample periods, daytime GEM flux was strongly correlated with solar radiation. The average nighttime GEM flux was slightly negative and was not well correlated with any of the measured meteorological variables. Preliminary, empirical models were developed to estimate GEM emissions from snow surfaces in northern New York. These models suggest that most, if not all, of the Hg deposited with and to snow is reemitted to the atmosphere.     

The effects of contamination of soil with copper,lead and arsenic on the growth and composition of plants

Summary Accumulations of copper, lead and arsenic in soils affected by orchard sprays or mining were investigated in relation to their effects on growth and composition of plants. Seasonal variations in concentrations of the elements in pasture plants sampled from contaminated soils in the field are reported. The effects of soil temperature and applications of the nutrients P, S and N on the composition of plants grown in contaminated soils were investigated in glasshouse experiments.The copper concentrations of pasture species sampled from sites which were formerly orchards were usually high (20 to 60 mg kg^–1) during most of the growing season and may present some risk of toxicity to grazing ruminant animals. Lead (0.8 to 21 mg kg^–1) and arsenic (<0.2 to 5.8 mg kg^–1) concentrations were within, or close to the normal range of concentration in plants. In the glasshouse experiments, soil temperature was found to be an important factor in the uptake of copper, lead and arsenic. There were significant differences in uptake between genotypes. Applications of fertilizers at rates equivalent to those used for commercial vegetable production generally resulted in small decreases in the concentrations of copper, lead and arsenic concentrations in silver beet.     

METAL UPTAKE AND ALLOCATION IN TREES GROWN ON CONTAMINATED LAND: IMPLICATIONS FOR BIOMASS PRODUCTION

Phytostabilization aims to reduce environmental and health risks arising from contaminated soil. To be economically attractive, plants used for phytostabilization should produce valuable biomass. This study investigated the biomass production and metal allocation to foliage and wood of willow (Salix viminalis L.), poplar (Populus monviso), birch (Betula pendula), and oak (Quercus robur) on five different soils contaminated with trace elements (TE), with varying high concentrations of Cu, Zn, Cd, and Pb as well as an uncontaminated control soil. In the treatment soils, the biomass was reduced in all species except oak. There was a significant negative correlation between biomass and foliar Cd and Zn concentrations, reaching up to 15 mg Cd kg^?1 and 2000 mg Zn kg ^?1 in willow leaves. Lead was the only TE with higher wood than foliage concentrations. The highest Pb accumulation occurred in birch with up to 135 mg kg ^?1 in wood and 78 mg kg ^?1 in foliage. Birch could be suitable for phytostabilization of soils with high Cd and Zn but low Pb concentrations, while poplars and willows could be used to stabilise soils with high Cu and Pb and low Zn and Cd concentrations.     

Grasshoppers and bushcrickets regionally extinct in the Czech Republic: consequence of the disappearance of habitats scattered on the edge of their ranges

According to the International Union for the Conservation of Nature, taxa extinct within a region but extant in other parts of the world should be classified as Regionally Extinct (RE). A taxon is designated RE when there is no reasonable doubt that the last individual capable of reproduction within a region has died or disappeared. A taxon can also be designated RE if it previously but no longer visited a particular region. The species Arcyptera fusca, Arcyptera microptera, Celes variabilis, Gampsocleis glabra, Locusta migratoria, Oedaleus decorus, and Stenobothrus rubicundulus had previously been found in only a small number of localities in the Czech Republic. We studied localities in the Czech Republic where they had been been previously reported but where their occurences had not been recently confirmed; the last specimens were observed in the 1940, 1960, or 1970s. All these species occurred at Czech localities representing borderline areas for such sub-Mediterranean and mountainous (Carpathian) species. The localities therefore had not offered optimal conditions for these insects, and the suitable biotopes were also scattered and isolated from each other. In most cases, these biotopes had disappeared due to change in management (either to natural or artificial forestation). Although certain of these species are excellent flyers (especially O. decorus), the known recent localities are separated by hundreds of kilometers. Based on our failure to find these species after extensive attempts, we conclude that discussed species should be considered regionally extinct in the Czech Republic. These species are of particularly vulnerable vegetation structures. The loss of these species indicate urgency for assessing status of co-occuring taxa.     

An Abandoned Copper Mining Site in Cyprus and Assessment of Metal Concentrations in Plants and Soil

Mining is an important source of metal pollution in the environment and abandoned mines are extremely restricted habitats for plants. Some plant species growing on metalliferous soils around mine tailings and spoil-heaps are metal-tolerant and accumulate high concentrations of metals. In this investigation, we aimed to perform a research in the CMC-abandoned copper mining area in Lefke-North Cyprus to assess the recent metal pollution in soil and plant systems. We collected 16 soil samples and 25 plant species from 8 localities around the vicinity of tailing ponds. Some concentrations of metals in soil samples varied from 185 to 1023 mg kg^?1 Cu, 15.2 to 59.2 mg kg^?1 Ni, 2.3 to 73.6 mg kg^?1 Cd and metals for plants ranged from 0.135 to 283 mg kg^?1 Cu, 0.26 to 31.2 mg kg^?1 Ni, 0.143 to 277 mg kg^?1 Cd. Atriplex semibaccata, Acacia cyanophylla, Erodium spp., Inula viscosa, Juncus sp., Oxalis pes-caprea, Pistacia lentiscus, Senecio vulgaris and Tragopogon sinuatus accumulated higher concentrations. BCF for Atriplex semibaccata was found very high, for this reason this plant can tentatively be considered as a hyperaccumulator of Cu and Cd, but it needs further investigation for its potential in phytoremediation.