JOURNAL OF HISTOTECHNOLOGY
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2025
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IF 1.8
Yanlin Wei,Wei Liu,Fengling Zhang,Yang Chen,Dongxin Wei,Hangyu Lin,Tao He
Inorganic mercury (Hg) and methylmercury (MeHg) have emerged as global pollutants owing to their long-term environmental stability and bioaccumulation. These heavy metals enter aquatic systems via industrial emissions, coal combustion, and natural processes, posing a serious threat to ecosystems and human health. This study assesses the impact of Hg2+ and MeHg on the growth and development of brine shrimp (Artemia franciscana) nauplii by analyzing the histopathological effects on their tissues. Brine shrimp nauplii from the Bohai Bay in China were selected as the study subjects and exposed to 1 μmol/L solutions of HgCl₂ and MeHgCl. Tissue sections were continuously taken at different immersion times. After staining with the standard hematoxylin-eosin (HE) method, the tissue morphology of brine shrimp nauplii under different forms of Hg stress was observed under a light microscope. The results showed that MeHg exhibited significantly greater toxicity to brine shrimp nauplii than Hg2+. Under the same exposure time, the MeHg group exhibited more pronounced epithelial cell damage, nuclear material disorder, and nucleoplasm diffusion outside the nucleus than the HgCl₂ group. This finding provides an important theoretical support for further research into the toxicological mechanisms of MeHg and Hg2+, and highlights that the toxic effects of methylmercury on aquatic organisms.
研究领域:
环境毒理学
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水生生态学
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海洋生物学
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组织病理学
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重金属污染
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2024
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IF 10.8
Qingyi Cao,Haiyan Hu,Wei Yuan,Jen-How Huang,Xuewu Fu,Xinbin Feng
Photo-, microbial, and abiotic dark reduction of soil mercury (Hg) may all lead to elemental mercury (Hg(0)) emissions. Utilizing lab incubations, isotope signatures of Hg(0) emitted from mining soils were characterized to quantify the interplay and contributions of various Hg reduction pathways, which have been scarcely studied. At 15 °C, microbial reduced Hg(0) showed a negative mass-dependent fractionation (MDF) (δ202Hg = −0.30 ± 0.08‰, 1SD) and near-zero mass-independent fractionation (MIF) (Δ199Hg = 0.01 ± 0.04‰, 1SD), closely resembling dark reduced Hg(0) (δ202Hg = −0.18 ± 0.05‰, Δ199Hg = −0.01 ± 0.03‰, 1SD). In comparison, photoreduced Hg(0) exhibited significant MDF and MIF (δ202Hg = −0.55 ± 0.05‰, Δ199Hg = −0.20 ± 0.07‰, 1SD). In the dark, Hg isotopic signatures remained constant over the temperature range of 15–35 °C. Nonetheless, light exposure and temperature changes together altered Hg(0) MIF signatures significantly. Isotope mixing models along with Hg(0) emission flux data highlighted photo- and microbial reduction contributing 79–88 and 12–21%, respectively, of the total Hg(0) emissions from mining soils, with negligible abiotic dark reduction. Microorganisms are the key driver of soil Hg(0) emissions by first dissolving HgS and then promoting ionic Hg formation, followed by facilitating the photo- and microbial reduction of organically bound Hg. These insights deepen our understanding of the biogeochemical processes that influence Hg(0) releases from surface soils.
研究领域:
环境科学
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地球化学
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微生物学
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产品关联
DOI
PubMed
高影响因子
GEOCHIMICA ET COSMOCHIMICA ACTA
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2023
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IF 5
Yunyun Ji,Shan Gao,Rui Si,Zhanhua Zhang,Li Tian,Wenyu Guan,Weichao Wang,Jiubin Chen,Wei Chen,Pedro J.J. Alvarez,Tong Zhang
Mercury and ferrous iron commonly co-exist in anaerobic environments, the hotspots of microbial mercury methylation that leads to formation of neurotoxic methylmercury. However, the influence of ferrous iron on mercury bioavailability and methylation remains unclear. Here, we discover that microbial methylmercury production is inhibited by iron addition in a non-monotonical manner, reaching the minimal level at the initial molar ratio of dissolved Fe/Hg as 1/3, when highly aggregated Hg–S–Fe nanoparticles occur and prevent the nanoparticle–bacteria interactions. The dominant mercury species formed upon Hg–S–Fe co-precipitation is iron-incorporated nano-metacinnabar with short-range structural disorder. The methylation potential of this mercury species is inversely correlated with the aggregation state of nanoparticles. The non-monotonical trends of the aggregation state and subsequent methylation of nano-metacinnabar are due to the opposite effects of ferrous iron on the nucleation and particle attachment that determine the formation of nanoparticle aggregates. Increased Fe/Hg ratio hinders particle nucleation and thus decreases the density of particle monomers for aggregation. However, Fe substitution of sub-surface Hg weakens the inner-sphere coordination of surface Hg with natural thiol ligands and consequently enhances nano-metacinnabar aggregation. This new mechanistic insight is important for assessing and minimizing the risks of mercury methylation, and informs how intertwined iron and sulfur cycling may influence metal bioavailability in the changing environment.
研究领域:
环境科学
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微生物学
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产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
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2018
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IF 6.042
Jian-Yu Yang,Ting Yang,Xiao-Yan Wang,Ming-Li Chen,Yong-Liang Yu,Jian-Hua Wang
Fluorescent nanoparticles are widely used for sensing biologically significant species. However, there are only rare reports of the discrimination or speciation of metal species. In this work, we report for the first time the speciation of mercury (Hg2+) and methylmercury (CH3Hg+) by taking advantage of the fluorescence feature of folic-acid-capped gold nanoclusters (FA-AuNCs). FA-Au NCs exhibit an average size of 2.08 ± 0.15 nm and a maximum emission at λex/λem = 280/440 nm with a quantum yield of 27.3%. It is interesting that Hg2+ causes a significant quench of the fluorescence of FA-Au NCs, whereas CH3Hg+ leads to a remarkable fluorescence enhancement. On the basis of this discriminative fluorescent response between Hg2+ and CH3Hg+, a novel nanosensor for the speciation of CH3Hg+ and Hg2+ was developed, providing limits of detection (LODs) of 28 nM for Hg2+ and 25 nM for CH3Hg+ within 100–1000 nM. This sensing system is highly selective to mercury. Its practical applications were further demonstrated by the analysis of CH3Hg+ and the speciation of mercury (CH3Hg+ and Hg2+) in environmental water and fish samples.
研究领域:
环境科学
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分析化学
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DOI
高影响因子
MICROCHEMICAL JOURNAL
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2012
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IF 3.048
Yi Wu,Yong-Ill Lee,Li Wu,Xiandeng Hou
A simple method was proposed for mercury cold vapor generation (CVG) in tetramethylammoniumhydroxide (TMAH) solution for speciation analysis of ultratrace inorganic mercury and total mercury in biological samples by inductively coupled plasma mass spectrometry (ICP-MS). Prior to analysis, 100–300 mg of the biological sample was accurately weighed into a conical tube. Then, 2 mL of 25% (m/v) TMAH solution was added to the sample, incubated at room temperature for several hours (hair, 3 h), and diluted to 25 mL with water. Finally, inorganic mercury was directly determined by CVG-ICP-MS, while microwave-assisted oxidation with H 2 O 2 was needed for total mercury detection. The concentration of organic mercury, mainly methylmercury , was obtained by difference of total mercury and inorganic mercury. Only one calibration curve against mercury aqueous standards in 2% TMAH medium was needed for both procedures. Optimum conditions for mercury CVG, as well as sample preparation and microwave-assisted digestion were investigated in detail. A limit of detection (LOD, 3σ) of 3 ng L − 1 was obtained and the linear working range was 0.1–100 μg L − 1 . Validation data were provided based on the analysis of water samples, as well as a CRM human hair sample (GBW 070601). This is a simple, rapid, ultrasensitive and relatively green method for the determination of mercury in water and biological samples.
研究领域:
分析化学
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环境科学
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生物学
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产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
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2015
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IF 5.636
Li Deng,Yan Li,Xiuping Yan,Jun Xiao,Cheng Ma,Jing Zheng,Shaojun Liu,Ronghua Yang
Methylmercury (CH3Hg+), the common organic source of mercury, is well-known as one of the most toxic compounds that is more toxic than inorganic or elemental mercury. In seabeds, the deposited Hg2+ ions are converted into CH3Hg+ by bacteria, where they are subsequently consumed and bioaccumulated in the tissue of fish, and finally, to enter the human diet, causing severe health problems. Therefore, sensitive and selective detection of bioaccumulation of CH3Hg+ in fish samples is desirable. However, selective assay of CH3Hg+ in the mercury-containing samples has been seriously hampered by the difficulty to distinguish CH3Hg+ from ionic mercury. We report here that metal amalgamation, a natural phenomenon occurring between mercury atoms and certain metal atoms, combining with DNA-protected silver nanoparticles, can be used to detect CH3Hg+ with high sensitivity and superior selectivity over Hg2+ and other heavy metals. In our proposed approach, discrimination between CH3Hg+ and Hg2+ ions was realized by forming Ag/Hg amalgam with a CH3Hg+-specific scaffold. We have found that Ag/Hg amalgam can be formed on a CH3Hg+-specific DNA template between silver atoms and mercury atoms but cannot between silver atoms and CH3Hg+. With a dye-labeled DNA strand, the sensor can detect CH3Hg+ down to the picomolar level, which is >125-fold sensitive over Hg2+. Moreover, the presence of 50-fold Hg2+ and 106-fold other metal ions do not interfere with the CH3Hg+ detection. The results shown herein have important implications for the fast, easy, and selective detection and monitoring of CH3Hg+ in environmental and biological samples.
研究领域:
环境科学
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分析化学
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毒理学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Ji Chen,Gongren Hu,Jiang Liu,Alexandre J. Poulain,Qiang Pu,Rong Huang,Bo Meng,Xinbin Feng
The production of methylmercury (MeHg) in flooded paddy fields determines its accumulation in rice grains; this, in turn, results in MeHg exposure risks for not only rice-eating humans but also wildlife. Nitrogen (N) fertilizers have been widely applied in rice cultivation fields to supply essential nutrients. However, the effects of N fertilizer addition on mercury (Hg) transformations are not unclear. This limits our understanding of MeHg formation in rice paddy ecosystems. In this study, we spiked three Hg tracers ( 200 Hg II , Me 198 Hg, and 202 Hg 0 ) in paddy slurries fertilized with urea, ammonium, and nitrate. The influences of N fertilization on Hg methylation, demethylation, and reduction and the underlying mechanisms were elucidated. The results revealed that dissimilatory nitrate reduction was the dominant process in the incubated paddy slurries. Nitrate addition inhibited Hg II reduction, Hg II methylation, and MeHg demethylation. Competition between nitrates and other electron acceptors (e.g., Hg II , sulfate, or carbon dioxide) under dark conditions was the mechanism underlying nitrate-regulated Hg transformation. Ammonium and urea additions promoted Hg II reduction, and anaerobic ammonium oxidation coupled with Hg II reduction (Hgammox) was likely the reason. This work highlighted that nitrate addition not only inhibited Hg II methylation but also reduced the demethylation of MeHg and therefore may generate more accumulation of MeHg in the incubated paddy slurries. Findings from this study link the biogeochemical cycling of N and Hg and provide crucial knowledge for assessing Hg risks in intermittently flooded wetland ecosystems .
研究领域:
环境科学
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土壤学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Yongpeng Ma,Jiandong Wang,Wentao Gu,Xiaojing Zhang,Haomiao Xu,Wenjun Huang,Yonghui Guo,Shaobo Wang
Herein, MoS 2 was used in a MoS 2 /H 2 O heterogeneous system for the heterogeneously catalyzed removal of Hg 0 from flue gas. Hg 0 removal efficiency reached 77.6% at 25 °C when the dosage of MoS 2 was 0.200 g/L in aqueous suspension. The observed effects of MoS 2 dosage and inlet Hg 0 concentration on Hg 0 removal efficiency revealed that the gas–liquid mass transfer process is the limiting step of Hg 0 removal. Low pH and low temperature were conducive to Hg 0 removal. SO 2 in the flue gas was absorbed by MoS 2 , and the simultaneous decrease in solution pH resulted in a slight increase in Hg 0 removal efficiency. The presence of NO in the flue gas enhanced Hg 0 removal efficiency. Common anions, such as NO 3 − , SO 4 2− , and CO 3 2− , have no obvious effect on Hg 0 removal. However, Cl − improved Hg 0 removal efficiency by 11% because of the production of HgCl n 2−n . The kinetics and mechanism of Hg 0 removal were studied, and the results indicated that Mo acted as a bridge and catalyst for Hg 0 oxidation, while S immobilized Hg 2+ by formation of HgS on MoS 2 .
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF TRACE ELEMENTS IN MEDICINE AND BIOLOGY
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2024
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IF 3.6
Zhaoliang Hu,Xiao Wu,Yi Du,Wenyu Zou,Haijuan Dong,Min Song,Taijun Hang,Yuting Lu
Background Cinnabaris (α-HgS), a mineral traditional Chinese material medica , has been used in combination with other herbs manifesting some definite therapeutic effects for thousands of years. But the currently reported mercury poisoning incidents raised the doubts about the safety of Cinnabaris-containing traditional Chinese medicines (TCMs). Baizi Yangxin Pills (BZYXP) is a Cinnabaris-containing TCM widely used in clinical practice. This study evaluated the health risk of mercury exposure from BZYXP in healthy volunteers based on the total mercury and mercury species analysis of blood and urine after single and multiple doses of BZYXP. Methods Blood pharmacokinetics and urinary excretion studies of mercury were compared between single (9 g, once daily) and multiple doses (9 g, twice daily, continued for 7 days) of BZYXP. The whole blood and urine samples were collected at the specific points or periods after the administration of BZYXP. The total mercury and mercury species in blood and urine samples were determined by cold vapor-atomic fluorescence spectrometry (CV-AFS) and HPLC-CV-AFS, respectively. Results The mercury was excreted slowly and accumulated obviously after continuous exposure of BZYXP. Moreover, the well-known neurotoxin methylmercury (MeHg) was detected in blood samples after 7 days’ administration of BZYXP. In the urine samples, only Hg(II) was detected. Therefore, long-term use of BZYXP will cause mercury poisoning due to mercury's high accumulative properties and MeHg formation. Conclusion Cinnabaris-containing TCMs such as BZYXP should be restricted to cases in which alternatives are available, and the blood mercury species profile should be monitored during the long-term clinical medication.
研究领域:
药理学
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毒理学
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传统医学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
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IF 12.2
Fang Fang,Lingyun Ding,Yaoyu Zhang,Xuejiao Qiao,Lu Qian,Ruqian Wei,Hanchun Chen,Haodong Ji,Bin Pi,Ming Hung Wong,Huchun Tao,Nan Xu,Lijuan Zhang
There has been a serious health and environmental concern in conversion of inorganic mercury (Hg) to the neurotoxin, methylmercury (MeHg) by anaerobic microbes, while very little is known about the potential role of vitamin B9 (VB9) regulator in the biochemical generation of MeHg. This study innovatively investigated bacterial Hg methylation by Geobacter sulfurreducens PCA in the presence of VB9 under two existing scenarios. In the low-complexing scenario, the bacterial MeHg yield reached 68 % higher than that without VB9 within 72 h, which was attributed to free VB9-protected PCA cells relieving oxidative stress, as manifested by the increased expression of Hg methylation gene ( hgcAB cluster by 19–48 %). The high-complexing scenario emphasized the intracellular Hg accumulation (38–45 %) after 12 h, as indicated by the increased expression of outer membrane protein-related and mercuric reductase-encoding genes, indicating the inefficient bioavailability of Hg due to a gradual shift from Hg reduction toward Hg 0 re-oxidation controlled by competitive ligand exchange. These results suggested that VB9 application significantly raised the potential for bacterial Hg methylation and cellular accumulation, thus proposing insights into the biochemical behaviors of hazardous Hg in farming environments where vulnerable organisms are more possibly co-exposed to higher levels of Hg and VB9.
研究领域:
环境科学
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微生物学
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毒理学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2017
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IF 3.359
Chao Han,Wei Wang,Feng Xie,Ting'an Zhang
Mercury is one of the most severe environmental pollutants due to its high toxicity, and the detoxification of mercury-containing solid wastes is a critical issue worldwide. In this work, thiosulfate solution has been used to leach mercury from mercuric sulfide. The influence of leaching conditions, including initial pH, molar ratio of copper to thiosulfate ([Cu]/[S 2 O 3 2− ]), and temperature on mercury leaching from mercuric sulfide, was investigated. The mercury leaching rate can reach as high as 92.37% after 7-h leaching under the optimized condition of initial pH 8.50, molar ratio of copper to thiosulfate 0.1 and leaching temperature 313 K. X-ray diffraction (XRD), scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) was used to analyze the leaching residue. The results show that copper in its thiosulfate complex can be substituted by mercury via Lewis substitution and cuprous sulfide was formed on the surface of leaching residue. The kinetics of mercuric sulfide leaching with cuprous-thiosulfate solutions was controlled by the product layer diffusion.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
FUEL
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2016
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IF 3.611
Shunlin Tang,Lina Wang,Xinbin Feng,Zhaohui Feng,Ruiyang Li,Huipeng Fan,Ke Li
Mercury species distribution in the flue gas from three typical coal-fired power plants have been investigated using a C-5000 sampler for Ontario Hydro Method (OHM) to evaluate specified Hg emission inventories in the largest coal-production province of China, Inner Mongolia. The feed coal, bottom ash, fly ash and gypsum have also been sampled in the field. Mercury emissions are in the dominant form of Hg 0 (>85%). The Hg 2+ (<15%) and the Hg p (<2%) emissions are minor fractions of Hg t in the flue gas. The wet limestone flue gas desulfurization device (WLFGD) showed much higher removal efficiency for Hg 2+ (87–95%) than for the other two Hg species. The input Hg/output Hg varied from 92% to 115% for the tested 3 coal-fried utility boilers during sampling time. We obtained comprehensive Hg discharge factors, including direct atmospheric Hg emission factors and indirect discharge factors of Hg associated with bottom ash, fly ash and gypsum, to the environment, designating the fates of Hg in coal. We estimated the Hg discharges from coal-fired power plants in Inner Mongolia in 2008–2014 and expanded to China. The maximum of direct Hg emissions from coal-fired power plants of Inner Mongolia was 24 Mg in 2012. The Chinese coal-fired power plants emitted directly 100 Mg Hg to the atmosphere every year at the nationwide air control actions. The maximum discharges of Hg associated with fly ash and gypsum of Inner Mongolia was 81 Mg and 11 Mg in 2012, respectively. The national Hg discharges with fly ash and gypsum every year are respectively about 300 Mg and 82 Mg, majority of which may be reemitted to the atmosphere by the utilization industry. Therefore, mercury emissions from coal-fired power plants are not the largest single source of Hg to the atmosphere in normal operation of the current efficient denitrification, particles control and desulfurization devices. Instead, the utilization industry of fly ash and gypsum would be emitting more Hg to the atmosphere.
研究领域:
环境科学
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能源与动力工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）