Mercury in the natural environment: Biogeochemical cycles and associated health risks

Journal of Geochemical Exploration, Journal Year: 2024, Volume and Issue: unknown, P. 107594 - 107594

Published: Sept. 1, 2024

Language: Английский

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Effects of composite environmental materials on the passivation and biochemical effectiveness of Pb and Cd in soil: Analyses at the ex-planta of the Pak-choi root and leave

Environmental Pollution, Journal Year: 2022, Volume and Issue: 309, P. 119812 - 119812

Published: July 20, 2022

Language: Английский

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Mercury (Hg) Contaminated Sites in Kazakhstan: Review of Current Cases and Site Remediation Responses

International Journal of Environmental Research and Public Health, Journal Year: 2020, Volume and Issue: 17(23), P. 8936 - 8936

Published: Dec. 1, 2020

Mercury (Hg) emissions from anthropogenic sources pose a global problem. In Central Asia, Kazakhstan’s central and northern regions are among the most severely Hg-contaminated territories. This is due to two former acetaldehyde (in Temirtau) chlor-alkali Pavlodar) plants, discharges which during second half of 20th century were estimated over 2000 tons elemental Hg. However, exact quantities Hg released through atmospheric environment, controlled nearby aquatic systems, leakages in cell plant, contaminated sludge still unknown. The present review initiation comprehensive field investigation study on current state these sites. It aims provide critical published literature soils, sediments, water, biota impacted ecosystems (Nura Irtysh rivers, Lake Balkyldak their surrounding areas). furthermore compares contamination episodes with selected similar international cases as well reviews recommends demercuration efforts. findings indicate that around plant site was significant mainly localized majority deposited topsoils riverbanks within 25 km discharge point. site, North Kazakhstan seriously receptor. local population both might be exposed fish consumption illegally caught rivers reservoirs. Since data limited investigations conducted before 2010 given persisting nature Hg, recent up-to-date environmental assessment for sites highly needed, particularly formerly detected hotspots. Due incomplete remediation efforts, recommendations by several researchers territories include ex-situ soil washing, pulping gravitational separation, ultrasound transgenic algae electrokinetic recovery removal and/or confinement silt deposits soils latter. efficiency first needs validated. Findings lessons will useful not only scale but also valuable resources management globe.

Language: Английский

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Evolution of the Speciation and Mobility of Pb, Zn and Cd in Relation to Transport Processes in a Mining Environment

International Journal of Environmental Research and Public Health, Journal Year: 2020, Volume and Issue: 17(14), P. 4912 - 4912

Published: July 8, 2020

Elements in mining extracts can be potentially toxic if they are incorporated into soils, sediments or biota. Numerous approaches have been used to assess this problem, and these include sequential extractions selective extractions. These two methods limitations advantages, their combined use usually provides a rough estimate of the availability (bio)availability elements and, therefore, real potential as toxicants food chains. indirect speciation data interesting absolute terms, but work described here, aspect was developed further by assessing evolution availability-related relation transport processes from emission source, which mainly fluvial- wind-driven. This objective achieved characterizing tailings samples source soils at increasing distances investigate certain elements. The standard procedures employed included five-step extraction with ammonium acetate. results show that highest percentages Zn Pb tailings, sediment associated oxyhydroxides, along significant presence resistant mineralogical forms. In case Cd, its association organic matter is second-most important trapping mechanism area. physicochemical mechanisms did not transform main associations (oxyhydroxides forms) transects, produced chaotic pattern for other minor matrix decrease exchangeable carbonate-bound forms soils. Interestingly, sediments, mobile showed Pb. most probable reason observations Zn2+ form smithsonite (ZnCO3) hydrozincite (Zn5(CO3)2(OH)6), explains retention soil transect. contrast, Cd appear different mineral phases. order > involved produce an increase (bio)availability. trend bioavailability on moving away (tailings), maximum values obtained near area (200–400 m).

Language: Английский

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Mobility and speciation of mercury in soils from a mining zone in Villa Hidalgo, SLP, Mexico: A preliminary risk assessment

Applied Geochemistry, Journal Year: 2020, Volume and Issue: 122, P. 104746 - 104746

Published: Aug. 30, 2020

Language: Английский

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Distribution and pools of mercury in forest soils near recent and historical mercury emission sources in the central Czech Republic

Journal of Geochemical Exploration, Journal Year: 2021, Volume and Issue: 226, P. 106782 - 106782

Published: March 24, 2021

Language: Английский

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Assessment of Distribution of Potentially Toxic Elements in Different Environmental Media Impacted by a Former Chlor-Alkali Plant

Sustainability, Journal Year: 2021, Volume and Issue: 13(24), P. 13829 - 13829

Published: Dec. 14, 2021

Former industrially contaminated sites are a burden from the past that still pose environmental risks. During second half of 20th century, Pavlodar region in North Kazakhstan had been part Soviet Union’s industrial system operated chlor-alkali plant (CAP). The former CAP discharged approximately 135 t Hg into nearby Lake Balkyldak with total losses to water, soil, and air estimated around 1000 t. Pollution by potentially toxic elements (PTEs) due currently active enterprises is an under-investigated concern region. present study aims provide much-needed update on situation area evaluating contamination other selected PTEs (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Zn) surrounding environment urban zone. Soil, sediment, surface groundwater samples have collected several sampling campaigns carried out 2018 2019. Several concentrations exceeding maximum permissible (MPC), for soils sediments (in mg/kg; range: 0.0006 24, average: 0.56) water µg/L; 0.004 1340, 93). Critically high were mostly measured vicinity Balkyldak, where majority CAP, indicating persisting pollution studied A comparison soil showed less severe but some elevated values As, Se. inter-elemental relationship between assessed was weak, presence sources independent emitting sources. Further research exact territory needed, detailed human health risk characterization identify potential unacceptable risks strongly recommended.

Language: Английский

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Comparison of X-ray Fluorescence (XRF) and Atomic Absorption Spectrometry (AAS) Results for an Environmental Assessment at a Mercury Site in Kyrgyzstan

Applied Sciences, Journal Year: 2022, Volume and Issue: 12(4), P. 1943 - 1943

Published: Feb. 12, 2022

Khaidarkan, Batken Province, Kyrgyzstan is home to one of the world’s largest and last primary mercury mines. Doctors without Borders (MSF) Ministry Health (MOH) have found that region has an elevated rate non-communicable diseases (NCD) within country. NCD can be caused by environmental pollution. A human health risk assessment was conducted investigate heavy metal exposure. Using a hand-held X-ray fluorescence (XRF) spectrometer for soil screening faster less expensive than reliance on bench-scale methods. To establish site-specific conversion factor between XRF local MOH lab’s Atomic Absorption Spectrometry (AAS) with Pyrolyzer attachment, samples were collected in Khaidarkan surrounding villages. Samples analyzed three stages: situ, ex situ-bulk, situ-sieved. The situ-sieved AAS. Analysis results indicate situ readings used as qualitative tool screening, 1.7 most appropriate converting situ-bulk/ex AAS results. This analysis enables laboratory others use quick cost-effective monitoring Hg contamination soil.

Language: Английский

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Geochemical Assessment of Mineral Resource Potential in a Hg-Sb-Pb-Zn Mining Area: The Almadén and Guadalmez Synclines (South-Central Spain)

Applied Sciences, Journal Year: 2022, Volume and Issue: 12(22), P. 11351 - 11351

Published: Nov. 9, 2022

The geochemical data from surface soils are often neglected or questioned when prospecting for ore deposits within active mining districts due to the “background noise” produced by anthropogenic pollution derived activity. Large datasets on a national and international scale offer interesting possibilities discover prospective zones. In present work, Geochemical Atlas of Castilla–La Mancha were treated in an area with intense history Hg, Pb, Zn, Sb: Almadén Guadalmez synclines Alcudia Valley. sampling grid was densified adapt it main geological formations, cluster analysis carried out establish relationships between variables factor distinguish geogenic metallogenic factors. results showed very high concentrations some elements interest local background areas: Hg (51 mg kg−1), Pb (1190 Sb (45 variation coefficients. Cluster unveiled relationship most ore-forming metals (As, Sb, Ag) clear correlation organic matter, suggesting notable contribution soil. highlighted five factors, three two elements. Despite being candidate form separate factor, its aerial deposition large number outliers syncline contributed integrating element into factor. Instead, factors F4 (Pb Zn) F5 (As Sb) delimited areas both far known exploited mines. Some these coincided discovered mineralized zones, specifically SE derelict mine, confirming usefulness statistical tools recent

Language: Английский

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Potential Human Exposure to Mercury (Hg) in a Chlor-Alkali Plant Impacted Zone: Risk Characterization Using Updated Site Assessment Data

Sustainability, Journal Year: 2021, Volume and Issue: 13(24), P. 13816 - 13816

Published: Dec. 14, 2021

Industrial activities have resulted in severe environmental contamination that may expose rural and urban populations to unacceptable health risks. For example, chlor-alkali plants (CAPs) historically contributed mercury (Hg) different compartments. One such site (a burden from the Soviet Union) is located an industrial complex Pavlodar, Kazakhstan. Earlier studies showed CAP operating second half of twentieth century caused elevated Hg levels soil, water, air, biota. However, follow-up with thorough risk characterization are missing. The present study aims provide a detailed based on data recent assessment around former CAP. ⅀HI (hazard index) ranged 9.30 × 10−4 0.125 (deterministic method) 5.19 2.54 10−2 (probabilistic method). results indicate acceptable excess human risks exposure region, i.e., other sources not considered. Air inhalation soil ingestion pathways highest values (up 99.9% 92.0%, respectively). residential scenario (among four) presented greatest risks, ranging 1.23 0.125. Although local population exposed coming Hg-contaminated media, directly could be performed due access prohibition. Furthermore, ingesting contaminated fish were covered as methyl-Hg was targeted. An additional needed for scenarios workers consuming Lake Balkyldak. Studies fate transport ecosystem also recommended considering methylation subsequent bioaccumulation food chain.

Language: Английский

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