A Low‐Sulfidation Epithermal Mineralization in the River Reef Zone,the Poboya Prospect,Central Sulawesi,Indonesia: Vein Textures,Ore Mineralogy,and Fluid Inclusions

The Poboya Prospect lies along the North Northwest ‐ South Southeast Palu‐Koro Fault Zone in the central part of the West Sulawesi Arc. The geology of the area consists of the Palu Metamorphic Complex overlain by the Paleogene‐Neogene Tinombo Formation of volcanosedimentary rocks, the Celebes Molasse sediment, and Late Cenozoic granitic rocks. Petrography, scanning electron microscope with energy‐dispersive spectrometry (SEM‐EDS), electron probe microanalyzer (EPMA), and fluid inclusion microthermometry were carried out to examine vein textures, ore mineralogy, and characteristics of the ore‐forming fluid responsible for mineralization in the River Reef Zone, the Poboya Prospect. Textures of quartz‐carbonate veins in the River Reef Zone include massive micro‐comb, moss, colloform, crustiform, mosaic, feathery, flamboyant, lattice bladed, ghost bladed, parallel bladed, and saccharoidal textures representing primary growth, recrystallization, and replacement. The homogenization temperature and fluid salinity are 240–250°C and 0.3–0.7 wt% NaCl eq., respectively. Ore minerals precipitated in the early stage consist of electrum, naumannite‐aguilarite, chalcopyrite, pyrite, marcasite, sphalerite, and pyrrhotite. Apart from pyrrhotite, these ore minerals were also precipitated in the late stage along with selenopolybasite, freibergite, argyrodite, pyrargyrite, and galena. Selenium more preferably occurs as the crystallographic replacement of sulfur in naumannite‐aguilarite, argyrodite, pyrargyrite, selenopolybasite, and freibergite instead of as independent selenide minerals. The low‐sulfidation epithermal deposit in the River Reef Zone, the Poboya Prospect, illustrates the potential of the West Sulawesi Arc, particularly along the Palu‐Koro Fault Zone, to host epithermal gold mineralization.     

Identifying semi-volatile contaminants in fish from Niyang River, Tibetan Plateau

This study investigated the contamination levels and profiles of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs) including dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) in fish from the Niyang River, Tibetan Plateau. The total concentrations of ∑PCB, ∑PBDE and ∑OCP were in the range of 0.246–1.056 ng/g (mean 0.540 ± 0.289 ng/g), 0.280–2.220 ng/g (mean 0.914 ± 0.643 ng/g) and 7.24–13.80 ng/g (mean 10.70 ± 2.31 ng/g), respectively. The total mercury concentration (HgT) in fish ranged from 85 to 217 ng/g dw with an average of 129 ng/g dw, and the concentrations of methyl mercury (MeHg) ranged from 61 to 160 ng/g dw with an average of 102 ng/g dw. The proportion of MeHg contributed to 66–91 % (average 80 %) of HgT for all samples, indicating that organic mercury was the predominant form of mercury in fish muscle. The results revealed that the fish from the Niyang River were contaminated with various persistent toxic pollutants and the potential influencing factors on the bioaccumulation concentration in fish were analyzed using Pearson’s correlation analysis.     

Coarse and fine particulates, Hg(p)-bound particulate concentrations and compositions study at Sha-Lu, central Taiwan

Ambient air and coarse, fine and particulate-bound mercury (Hg(p)) pollutants were collected and analyzed from March 17 to May 22 and September 3, 2009 to March 5, 2010 at a highway traffic site located in Sha-Lu, central Taiwan. This study has the following objectives: (1) to measure the coarse and fine particulates concentrations and the particulate-bound mercury Hg(p) which was attached to these particulate; (2) to determine the average Hg(p) compositions in coarse and fine particulates and (3) to compare the Hg(p) concentrations and compositions particulate in this study to the those obtained in other studies. The results obtained in this study indicated that the average ambient air PM_2.5, PM_2.5–10 and PM₁₀ were 18.79 ± 6.71, 11.22 ± 4.93 and 30.01 ± 10.27 μg/m³, respectively. The ranges of concentrations for Hg(p) in PM_2.5 were from 0.0016 to 0.0557 ng/m³, from 0.0006 to 0.0364 ng/m³ in PM_2.5–10 and from 0.0022 to 0.0862 ng/m³ in PM₁₀. In addition, the highest particle-bound mercury compositions in PM_2.5 were 16.85 ng/g and the lowest particle-bound mercury concentrations were 0.55 ng/g. The highest particle-bound mercury compositions in PM_2.5–10 were 13.88 ng/g and the lowest particle-bound mercury in PM_2.5–10 were 0.22 ng/g.     

Heavy metals in the Derwent Estuary

Analyses of the concentrations of Cd, Cr, Co, Cu, Fe, Pb, Mn, Hg, Ni, and Zn in filtered waters, suspended particulates, sediments, shellfish, fish, airborne particulates, and sewage have confirmed work of other investigators showing that the Derwent Estuary is heavily contaminated, particularly withmercury, cadmium, lead, andzinc, and have added further information regarding the distribution of each metal. Apparently most of the contamination originated from the earlier operation of a zinc refining plant. A study of shellfish growing in variously contaminated regions found that more than 20 species could be listed in order of their respective abilities to accumulate each heavy metal. For example, the mussel (Mytilus edulis) was found to be a good indicator of cadmium and mercury contamination, but less valuable as an indicator of zinc. The surf barnacle, (Catophragmus polymerus) was found to be one of the most sensitive biological indicators of cadmium contamination. An indication of the steps by which a waste metal is eventually accumulated at high and even toxic concentrations in seafoods, may be seen from a comparison of the relative concentrations of cadmium, lead, mercury, and zinc found in mussels, sediments, suspended particulates, and filtered waters. The high concentrations recorded for metals include: 1,100 μg/g Hg, 10,000 μg/g Zn, and 862 μg/g Cd in dried sediments; 1,500 μg/g Cd in airborne dust fallout; 200 μg/g Cd and 100,000 μg/g Zn in dried oysters; and 16 μg/l Hg, 15 μg/l Cd and 1,500 μg/l Zn in filtered waters.     

Behavior of mercury in an urban river and its accumulation in aquatic plants

The characteristics of mercury in the aquatic environment have been intensively studied in mining areas with heavy mercury pollution but little work has been conducted in urban areas, with no significant Hg source. This paper presents a study of the Haihe River, which flows through an urban area in North China. The concentrations of total mercury (THg) and methylmercury (MeHg) in the river water were 3.6–31.2 and 0.12–3.21 ng/l, and the corresponding values in river sediment were 22.9–374.8 and 0.03–0.46 μg/kg. These values are lower than the reported values from mining areas. The THg concentration in sediment samples collected from the urban areas was higher than that from the rural areas and the global background levels, indicating the influence of urbanization on mercury contamination. Samples of typical riparian and floating plants, reed and hornwort, were collected. Correlation analysis showed that sediment is the major source of THg and MeHg in reed and water is the major source of MeHg in hornwort. The higher bioaccumulation factor of reed indicates its higher potential to accumulate MeHg from the environment.     

A novel label-free method for determination of inorganic mercury in environmental aqueous media using BSA-modified silver nanoparticles

A selective colorimetric sensor was developed for rapid and fast determination of highly toxic Hg²⁺ according to decolorization of unmodified silver nanoparticles (AgNPs). A simple strategy was used for providing water-soluble AgNPs. Bovine serum albumin (BSA) and sodium borohydride were used as stabilizing and reducing agents, respectively. AgNPs, prepared by BSA, were stable for 2 months. The freshly prepared bio-stabilized AgNPs were brownish yellow in color owing to the severe surface plasmon resonance (SPR) peak at 420 nm. The yellow AgNPs solution became colorless in the presence of Hg²⁺, as well as a gradual blue shift, and decrease in the intensity of absorption peak was observed with increasing the concentrations of mercury, because of aggregation of the nanoparticles. The calibration curve was linear from 5 to 80 µM (r = 0.994). The detection limit was 2.7 µM. Selective determination of mercury (II) ions was performed in the presence of other ions. To investigate the practical applications of BSA/AgNPs in real samples, mercury determination was performed in a groundwater sample and good recoveries (>94.0 %) were obtained.     

Heavy metals and metalloids in sediments from the Llobregat basin,Spain

The concentration of heavy metals and metalloids (As, Cd, Cr, Cu, Hg, Ni, Pb, Sb and Zn) in sediments from the River Llobregat and its tributaries (Anoia and Cardener) was studied. Samples collected at 17 locations during four different periods were analysed by ICP-MS. The heavy metal enrichment at some sites along the rivers reflects the effects of agricultural activities, sewage treatment plant effluents, collectors' discharges and industrial activities. Principal component analysis (PCA) was used to describe trends in contamination and to find groupings among the investigated areas. The Llobregat and Cardener sediments appeared to have features of an unpolluted river, even though significant amounts of domestic and industrial wastewater are discharged into these rivers. On the other hand, the sediments from the River Anoia showed high Cr and Hg levels originating from industrial activities. The concentrations of Cr and Hg ranged from 91–540 and 0.28–2.29 µg/g respectively.     

Fluorine and chlorine in mantle minerals and the halogen budget of the Earth’s mantle

The fluorine (F) and chlorine (Cl) contents of arc magmas have been used to track the composition of subducted components, and the F and Cl contents of MORB have been used to estimate the halogen content of depleted MORB mantle (DMM). Yet, the F and Cl budget of the Earth’s upper mantle and their distribution in peridotite minerals remain to be constrained. Here, we developed a method to measure low concentrations of halogens (≥0.4 µg/g F and ≥0.3 µg/g Cl) in minerals by secondary ion mass spectroscopy. We present a comprehensive study of F and Cl in co-existing natural olivine, orthopyroxene, clinopyroxene, and amphibole in seventeen samples from different tectonic settings. We support the hypothesis that F in olivine is controlled by melt polymerization, and that F in pyroxene is controlled by their Na and Al contents, with some effect of melt polymerization. We infer that Cl compatibility ranks as follows: amphibole > clinopyroxene > olivine ~ orthopyroxene, while F compatibility ranks as follows: amphibole > clinopyroxene > orthopyroxene ≥ olivine, depending on the tectonic context. In addition, we show that F, Cl, Be and B are correlated in pyroxenes and amphibole. F and Cl variations suggest that interaction with slab melts and fluids can significantly alter the halogen content of mantle minerals. In particular, F in oceanic peridotites is mostly hosted in pyroxenes, and proportionally increases in olivine in subduction-related peridotites. The mantle wedge is likely enriched in F compared to un-metasomatized mantle, while Cl is always low (<1 µg/g) in all tectonic settings studied here. The bulk anhydrous peridotite mantle contains 1.4–31 µg/g F and 0.14–0.38 µg/g Cl. The bulk F content of oceanic-like peridotites (2.1–9.4 µg/g) is lower than DMM estimates, consistent with F-rich eclogite in the source of MORB. Furthermore, the bulk Cl budget of all anhydrous peridotites studied here is lower than previous DMM estimates. Our results indicate that nearly all MORB may be somewhat contaminated by seawater-rich material and that the Cl content of DMM could be overestimated. With this study, we demonstrate that the halogen contents of natural peridotite minerals are a unique tool to understand the cycling of halogens, from ridge settings to subduction zones.     

Regional geochemical baseline concentration of potentially toxic trace metals in the mineralized Lom Basin,East Cameroon: a tool for contamination assessment

The distribution of trace metals in active stream sediments from the mineralized Lom Basin has been evaluated. Fifty-five bottom sediments were collected and the mineralogical composition of six pulverized samples determined by XRD. The fine fraction (<?150 µm) was subjected to total digestion (HClO₄?+?HF?+?HCl) and analyzed for trace metals using a combination of ICP-MS and AAS analytical methods. Results show that the mineralogy of stream sediments is dominated by quartz (39–86%), phyllosilicates (0–45%) and feldspars (0–27%). Mean concentrations of the analyzed metals are low (e.g. As?=?99.40 µg/kg, Zn?=?573.24 µg/kg, V?=?963.14 µg/kg and Cr?=?763.93 µg/kg). Iron and Mn have significant average concentrations of 28.325 and 442 mg/kg, respectively. Background and threshold values of the trace metals were computed statistically to determine geochemical anomalies of geologic or anthropogenic origin, particularly mining activity. Factor analysis, applied on normalized data, identified three associations: Ni–Cr–V–Co–As–Se–pH, Cu–Zn–Hg–Pb–Cd–Sc and Fe–Mn. The first association is controlled by source geology and the neutral pH, the second by sulphide mineralization and the last by chemical weathering of ferromagnesian minerals. Spatial analysis reveals similar distribution trends for Co–Cr–V–Ni and Cu–Zn–Pb–Sc reflecting the lithology and sulphide mineralization in the basin. Relatively high levels of As were concordant with reported gold occurrences in the area while Fe and Mn distribution are consistent with their source from the Fe-bearing metamorphic rocks. These findings provide baseline geochemical values for common and parallel geological domains in the eastern region of Cameroon. Although this study shows that the stream sediments are not polluted, the evaluation of metal composition in environmental samples from abandoned and active mine sites for comparison and environmental health risk assessment is highly recommended.     

Concentration of arsenic by selected vegetables cultivated in the Yamuna flood plains (YFP) of Delhi,India

High Arsenic (As) concentrations have been reported in superficial water in the Yamuna flood plains (YFP), Delhi, which is being extensively used for agriculture. The concentration of As in some common vegetables such as Solanum lycopersicum (tomato), Abelmoschus esculentus (lady’s finger), Solanum melongena (brinjal), Lagenaria siceraria (bottle gourd), Raphanus sativus (radish), Zea mays (corn), and Luffa acutangula (ridge gourd) has been studied in this work. The range of As concentrations (dry weight) varies from 0.6 to 2.52 mg/kg with the highest accumulation of 2.52 mg/kg in radish followed by tomato (2.36 mg/kg). The order of As concentration in the decreasing order is R. sativus > S. lycopersicum > Z. mays > L. acutangula > L. siceraria > S. melongena > A. esculentus. Thus, As accumulation is the highest in roots and the lowest in least juicy fruits. The daily dietary intake of As through the consumption of various vegetables was also calculated. Though the mean As concentration was the highest in radish (2.52 mg/kg) but the highest amount of As is being consumed through tomato (0.383 mg/day), which is nearly three times the World Health Organization’s provisional maximum tolerable daily intake limit of 0.126 mg/day for a 60 kg person. High concentration of As in vegetables grown in YFP, Delhi is being reported here. This high contamination is primarily due to the presence of As in irrigation water having its source from coal-based thermal power plants in the vicinity of the area. If not checked properly, it will pose a serious health risk to people living in these densely populated areas surrounding YFP.     

Measurement of ambient air particulate pollutant concentrations and dry depositions for PS-1 combined with dry deposition plate at a wetland site

In this study, the concentrations of ambient total suspended particulates (TSP) and their dry deposition were measured using a PS-1 sampler with dry deposition plates at a wetland sampling site in central Taiwan during a sampling period from October 2016 to December 2016. The PS-1 sampler was fixed at set distances (1.5 and 2 m) from a dry deposition plate, and sampled particulate pollutants were sampled to determine their concentrations and dry deposition rates simultaneously. A dry deposition plate 3 m from the PS-1 sampler was also used to collect dry deposition particulate. This plate was also used to compare dry depositions from ambient air, collected from new device. The results thus obtained indicated that the average dry deposition rates on the dry deposition plates that were 1.5 and 2 m from the sampler were 103.15 and 103.94 µg/m² min, respectively, in October, 83.36 and 100.18 µg/m² min in November, and 171.2 and 157.5 µg/m² min in December. These dry deposition rates were compared with that 3 m away from the PS-1 sampler. The statistical t test revealed no significant differences between the dry depositions on dry deposition plates at 1.5 and 2 m from the sampler. The dry deposition rates at 1.5 and 2 m from the sampler did not differ significantly from that at 3 m from the PS-1 sampler. This study proves that a PS-1 sampler can be combined with a dry deposition plate to measure TSP concentrations and dry depositions simultaneously using a single device.     

Predictive environmental impact assessment of total petroleum hydrocarbons in petrochemical wastewater effluent and surface sediment

The contamination level of total petroleum hydrocarbons (TPH) in wastewater and surface sediment samples from the Petrochemical Special Economic Zone (PETZONE) and adjacent coastal area in Musa Bay (in Northwest of Persian Gulf) was examined. Concentrations of TPH in the Musa Bay sediments ranged from 16.48 to 97.15 µg/g dry weight (dw) with average value of 48.98 ± 30.36 µg/g dw. The highest concentrations were estimated in stations close to the coastline, locations affected by intensive petrochemical discharges and shipping activities. The average TPH concentration in the PETZONE wastewater effluent samples was 5.22 mg/L, with a range of 0.06–35.33 mg/L. Regarding environmental impact assessment, the concentration of TPH was lower than the wastewater effluent discharge standard at most of the monitoring stations inside PETZONE companies, with the exception of stations 15, 16 (Imam Khomeini petrochemical company 1, 2) and 17 (Razi petrochemical company). These stations were considered as moderate environmental aspects, suggesting that concentration of TPH in the wastewater effluents of these petrochemical companies could be considered as contaminants of concern in the PETZONE area.     

Environmental risk assessment of platinum cytotoxic drugs: a focus on toxicity characterization of hospital effluents

Platinum-based cytotoxic drugs are complexes of Pt used in 50–70% of cancer patients. This study was performed during 2015, in two oncology wards of Qom hospitals in Iran. Sampling was carried out using effluent of the oncology wards for measurement of total Pt concentration. Analysis was performed by ICP–OES, and limit of detection was determined (LODs = 1 µg/L). During the sampling days, the total Pt concentration in the wastewater effluent oncology ward ranged from 5 to 762 µg/L at Shahid Beheshti Hospital and from 3 to 629 µg/L at Hazrat Masoumeh Hospital. According to the results from concentration of cytotoxic drugs, the predicted environmental concentrations (PECs) (ng/L) in wastewater treatment plant effluent and river for cisplatin, carboplatin and oxaliplatin were determined. Calculated RQ_hww showed that \(\sum {\text{RQ}}_{\text{hww}} = 1.19\). Thus, the total platinum compound drug could have potential toxicity effect on aquatic organisms. It was concluded that monitoring of cytotoxic drugs residue in hospital effluent must be considered because of their toxicity and impact on aquatic pollution. The results also revealed that PEC < 10 ng/L for all the platinum compound drugs and sum of the PEC calculation (\(\sum {\text{PEC}}_{{{\text{cis}},{\text{carbo}},{\text{oxali}}}}\)).     

Antioxidants and chromium reductases by <Emphasis Type="Italic">Penibacillus</Emphasis> species enhance the growth of soybean under chromium stress

Hexavalent chromium [Cr(VI)] is used in various industries, but its improper and uncontrolled discharge contaminates the environment. In order to circumvent chromium toxicity, several physicochemical and biological strategies have been employed. Among biological approach, microbes convert toxic Cr(VI) to less soluble Cr(III) form and hence can be used to detoxify/remove Cr(VI) from contaminated environment. Considering these, present study was designed to assess the effect of chromium reductases and antioxidants secreted by Penibacillus species to detoxify Cr(VI) and concurrently to augment soybean growth. Bacterial strains (MAI1 and MAI2) were identified as Penibacillus sp. using 16S rRNA gene. Penibacillus species reduced Cr(VI) significantly at pH 7. Maximum Cr(VI) was reduced at 50 and 100 µg/ml of Cr(VI) concentrations. Penibacillus sp. also reduced Cr(VI) significantly at 25 and 35 °C as well as 1 g sodium alginate in 1 g polyvinyl alcohol. Bacterial strains reduced Cr(VI) into Cr(III) which were detected as 33 ± 1 and 35 ± 1 µg/ml in supernatant and 67 ± 2.5 and 65 ± 1 µg/ml in cell debris, respectively, after 120 h. Chromium reductase found in cell-free extract reduced almost all Cr(VI) compared to those observed in cell debris. Both malondialdehyde and antioxidant levels were increased with gradual increase in Cr(VI) concentration. Penibacillus species inoculated soybean plants had better growth and photosynthetic pigments under Cr(VI) stress.     

Removal of antimony and arsenic from circum-neutral mine drainage in Poproč, Slovakia: a field treatment system using low-cost iron-based material

The main aim of this paper was to investigate the removal efficiency of antimony (Sb) and arsenic (As) from circum-neutral mine drainage in the former Sb mine in Popro? (Slovakia) using a simple field treatment system based on the adsorption onto iron fillings. The treatment system consisted of two batch reactors with a volume of 1 m³: the first was used for settling of spontaneously precipitated ochreous sediments and the second, filled with reactive iron material, was designed to remove Sb and As from mine water. This passively operated treatment system contained 150 kg of low-cost iron fillings and was able to treat approximately 360 l of mine drainage per hour. The average removal efficiency of Sb and As reached 84 and 89% during a period of 2.3 years of the system operation, respectively. On average, dissolved Sb and As concentrations in mine drainage decreased from 175 to 24.3 µg/l and from 452 to 50.6 µg/l, respectively. Based on the electron microprobe (EMP) analyses of corrosion products developed on the surfaces of iron fillings, average Sb and As contents were 0.28 and 0.73 wt%, respectively. The chemical analyses of precipitated HFOs in the settling reactor showed that these ochreous precipitates contained up to 19.3 g/kg Sb and 65.8 g/kg As, indicating their natural role in the removal of the two metalloids from circum-neutral mine drainage. The results of transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses confirmed the presence of ferrihydrite and goethite in ochreous sediments.     

Findings on water quality in Upper Mustang (Nepal) from a preliminary geochemical and geological survey

The major ion and trace element chemistry of water samples, including springs, rivers and irrigation ditches, collected during a survey on August 2016 in the Upper Mustang region of the Mustang District of Dhawalagiri Zone (Nepal) has been investigated. The Upper Mustang region, a cold desert, represents a hot-spot for climate change: indeed, violent hailstorms and rainstorms have been recently observed, consequently exposing land to erosion. Results of this study indicate that waters in the region belong to the Ca–HCO₃, Ca–Mg–Cl–SO₄ and Na–K–Cl-types, reflecting different hydrochemical regimes. Uranium is widespread in waters, with concentrations up to 19 µg/L recorded in a potable water supply. Locally, anoxic conditions affect uranium mobility due to the low solubility of U(IV) minerals. Highly toxic thallium was detected in a thermal spring at an elevated concentration (45 µg/L Tl). The association of thallium with high concentrations of iron suggests that these elements are derived from pyrite oxidation. Detectable levels of thallium were also measured in the water of an irrigation ditch. Lithium concentrations ranged from 7 µg/L to 12 mg/L in the thermal water and showed a strong association with chloride ions. Arsenic concentrations up to 4.7 µg/L were measured in tributaries of the Kali Gandaki river. The data provide evidence that solutes in water have originated from an array of input sources, including carbonate dissolution, the dissolution of soluble salts, silicate weathering and localized sulfide oxidation. In particular, chemical weathering of granitic rocks is likely the primary source for metals and metalloids in waters. Since the erosion rate is a factor affecting lithological weathering, high-intensity rainfalls due to climate change are expected to influence the release and fate of potentially harmful elements in the in the Upper Mustang Valley.     

Assessment of environmental impact of open burning of scrap tyres on ambient air quality

Open burning of scrap (bicycle, motorcycle, car and truck) tyres (OBST) was simulated in the laboratory to investigate their impact on the ambient air quality. The tyre samples were burnt in combustion chamber, and gaseous pollutants (CO, NO₂ and SO₂) emitted were quantified, while concentrations and elemental compositions of emitted total suspended particulates (TSP) were determined. Emission level of SO₂ from all the tyre samples exceeded USEPA allowable (156.74 µg/m³) limit. CO due to car and truck tyres exceeded USEPA allowable (10,285.71 µg/m³) limit, while NO₂ concentration was below the allowable limit (56.33 µg/m³) only in bicycle tyre. 25% of all the gaseous pollutants emitted are within the Air Quality Index range of 101–150. TSP concentrations from all the tyre samples were higher than the Federal Ministry of Environment standard (250 µg/m³) for ambient TSP. There is strong correlation (R) of 0.885, 0.949 and 0.802 among all the gaseous (CO/NO₂, CO/SO₂ and NO₂/SO₂) pollutants, respectively, while the highest (0.999) and lowest (0.079) positive correlations were observed between Mg and Mn as well as Cd and Zn, respectively. The results of this study show that OBST emits hazardous pollutants, which pose serious threat to human health and environment.     

Characteristics and distributions of atmospheric mercury emitted from anthropogenic sources in Guiyang,southwestern China

Continuous measurements of speciated atmospheric mercury (Hg), including gaseous elemental mercury (GEM), particulate mercury (PHg), and reactive gaseous mercury (RGM) were conducted in Guizhou Province, southwestern China. Guiyang Power Plant (GPP), Guiyang Wujiang Cement Plant, Guizhou Aluminum Plant (GAP), and Guiyang Forest Park (GFP) in Guiyang were selected as study sites. Automatic Atmospheric Mercury Speciation Analyzers (Tekran 2537A) were used for GEM analysis. PHg and RGM were simultaneously collected by a manual sampling system, including elutriator, coupler/impactor, KCl-coated annular denuder, and a filter holder. Results show that different emission sources dominate different species of Hg. The highest average GEM value was 22.2 ± 28.3 ng·m^?3 and the lowest 6.1 ± 3.9 ng·m^?3, from samples collected at GPP and GAP, respectively. The maximum average PHg was 1984.9 pg·m^?3 and the minimum average 55.9 pg·m^?3, also from GPP and GAP, respectively. Similarly, the highest average RGM of 68.8 pg·m^?3 was measured at GPP, and the lowest level of 20.5 pg·m^?3 was found at GAP. We conclude that coal combustion sources are still playing a key role in GEM; traffic contributes significantly to PHg; and domestic pollution dominates RGM.     

Contamination of the environmental ecosystems by trace elements from mining activities of Badao bone coal mine in China

Bone coal, as a main mining object, can be used by local inhabitants as daily fuel and by local industrial enterprises as industrial fuel in Pinglin County, Shaanxi Province, China. This study reports how the environmental ecosystems have been polluted around the Badao bone coal mine. Geochemical samples (e.g. rock, water, soil, edible plant and animal) were collected. Bone coal from the Badao mine contains Se up to 75 µg/g Se and 28 µg/g Se in ashes after its combustion, with higher contents of other trace elements. Bone coal and its ash seem to be the main geochemical source of trace elements in soils and plants, which may cause contamination of the local environmental ecosystems. Three ways by which soils have been contaminated by these trace elements derived from bone coal are proposed in this paper. Radishes and beans have the ability to accumulate Mo and Se from soils. There is no obvious difference in concentrations of Cu, Cr and F in each plant from the two areas.