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Zhou X, Xiao Q, Deng Y, Hou X, Fang L, Zhou Y, Li F. Direct evidence for the occurrence of indigenous cadmium-based nanoparticles in paddy soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174621. [PMID: 38986703 DOI: 10.1016/j.scitotenv.2024.174621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 06/26/2024] [Accepted: 07/06/2024] [Indexed: 07/12/2024]
Abstract
Speciation of heavy metal-based nanoparticles (NPs) in paddy soils greatly determines their fate and potential risk towards food safety. However, quantitative understanding of such distinctive species remains challenging, because they are commonly presented at trace levels (e.g., sub parts-per-million) and extremely difficult to be fractionated in soil matrices. Herein, we propose a state-of-art non-destructive strategy for effective extraction and quantification of cadmium (Cd)-NPs - the most widespread heavy metal in paddy soils - by employing single particle inductively coupled plasma mass spectrometry (spICP-MS) and tetrasodium pyrophosphate (TSPP) as the extractant. Acceptable extraction efficiencies (64.7-80.4 %) were obtained for spiked cadmium sulfide nanoparticles (CdS-NPs). We demonstrate the presence of indigenous Cd-NPs in all six Cd-contaminated paddy soils tested, with a number concentration ranging from 2.20 × 108 to 3.18 × 109 particles/g, representing 17.0-50.4 % of the total Cd content. Furthermore, semi-spherical and irregular CdS-NPs were directly observed as an important form of the Cd-NPs in paddy soils, as characterized by transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy (TEM-EDX). This research marks a significant step towards directly observing indigenous Cd-NPs at trace levels in paddy soil, offering a useful tool for quantitative understanding of the biogeochemical cycling of heavy metal-based NPs in complex matrices.
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Affiliation(s)
- Xiaoxia Zhou
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China; National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Quanzhi Xiao
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Youwei Deng
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xianfeng Hou
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Liping Fang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Yanfei Zhou
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
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Chen D, Hu X, Chen C, Lin D, Xu J. Tailoring Fe 0 Nanoparticles via Lattice Engineering for Environmental Remediation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17178-17188. [PMID: 37903754 DOI: 10.1021/acs.est.3c05129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
Lattice engineering of nanomaterials holds promise in simultaneously regulating their geometric and electronic effects to promote their performance. However, local microenvironment engineering of Fe0 nanoparticles (nFe0) for efficient and selective environmental remediation is still in its infancy and lacks deep understanding. Here, we present the design principles and characterization techniques of lattice-doped nFe0 from the point of view of microenvironment chemistry at both atomic and elemental levels, revealing their crystalline structure, electronic effects, and physicochemical properties. We summarize the current knowledge about the impacts of doping nonmetal p-block elements, transition-metal d-block elements, and hybrid elements into nFe0 crystals on their local coordination environment, which largely determines their structure-property-activity relationships. The materials' reactivity-selectivity trade-off can be altered via facile and feasible approaches, e.g., controlling doping elements' amounts, types, and speciation. We also discuss the remaining challenges and future outlooks of using lattice-doped nFe0 materials in real applications. This perspective provides an intuitive interpretation for the rational design of lattice-doped nFe0, which is conducive to real practice for efficient and selective environmental remediation.
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Affiliation(s)
- Du Chen
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaohong Hu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Chaohuang Chen
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Daohui Lin
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
| | - Jiang Xu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
- Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China
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Li Z, Hadioui M, Wilkinson KJ. Extraction of Silicon-Containing Nanoparticles from an Agricultural Soil for Analysis by Single Particle Sector Field and Time-of-Flight Inductively Coupled Plasma Mass Spectrometry. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2049. [PMID: 37513060 PMCID: PMC10383646 DOI: 10.3390/nano13142049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 06/26/2023] [Accepted: 07/08/2023] [Indexed: 07/30/2023]
Abstract
The increased use of silica and silicon-containing nanoparticles (Si-NP) in agricultural applications has stimulated interest in determining their potential migration in the environment and their uptake by living organisms. Understanding the fate and behavior of Si-NPs will require their accurate analysis and characterization in very complex environmental matrices. In this study, we investigated Si-NP analysis in soil using single-particle ICP-MS. A magnetic sector instrument was operated at medium resolution to overcome the impact of polyatomic interferences (e.g., 14N14N and 12C16O) on 28Si determinations. Consequently, a size detection limit of 29 ± 3 nm (diameter of spherical SiO2 NP) was achieved in Milli-Q water. Si-NP were extracted from agricultural soil using several extractants, including Ca(NO3)2, Mg(NO3)2, BaCl2, NaNO3, Na4P2O7, fulvic acid (FA) and Na2H2EDTA. The best extraction efficiency was found for Na4P2O7, for which the size distribution of Si-NP in the leachates was well preserved for at least one month. On the other hand, Ca(NO3)2, Mg(NO3)2 and BaCl2 were relatively less effective and generally led to particle agglomeration. A time-of-flight ICP-MS was also used to examine the nature of the extracted Si-NP on a single-particle basis. Aluminosilicates accounted for the greatest number of extracted NP (~46%), followed by NP where Si was the only detected metal (presumably SiO2, ~30%).
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Affiliation(s)
- Zhizhong Li
- Department of Chemistry, Université de Montréal, 1375 Ave. Thérèse-Lavoie-Roux, Montreal, QC H2V 0B3, Canada
| | - Madjid Hadioui
- Department of Chemistry, Université de Montréal, 1375 Ave. Thérèse-Lavoie-Roux, Montreal, QC H2V 0B3, Canada
| | - Kevin J Wilkinson
- Department of Chemistry, Université de Montréal, 1375 Ave. Thérèse-Lavoie-Roux, Montreal, QC H2V 0B3, Canada
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Bai Q, Li Q, Liu J. Determination of the Particle Number Concentration, Size Distribution, and Species of Dominant Silver-Containing Nanoparticles in Soils by Single-Particle ICP-MS. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6425-6434. [PMID: 37036754 DOI: 10.1021/acs.est.2c08024] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The potential risk of various silver-containing nanoparticles (AgCNPs) in soils is related to the concentration, size, and speciation, but their determination remains a great challenge. Herein, we developed an effective method for determining the particle number, size, and species of dominant AgCNPs in soils, including nanoparticles of silver (Ag NPs), silver chloride (AgCl NPs), and silver sulfide (Ag2S NPs). By ultrasonication wand-assisted tetrasodium pyrophosphate extraction, these AgCNPs were extracted efficiently from soils. Then, multistep selective dissolution of Ag NPs, AgCl NPs, and whole Ag NPs/AgCl NPs/Ag2S NPs was achieved by 1% (v/v) H2O2, 5% (v/v) NH3·H2O, and 10 mM thiourea in 2% (v/v) acetic acid, respectively. Finally, the particle number concentration and size distribution of AgCNPs in the extracts and the remaining AgCNP particle number concentration after each dissolution were determined by single-particle inductively coupled plasma mass spectroscopy for speciation of the dominant AgCNPs. AgCNPs were detected in all five soil samples with the concentrations of 0.23-8.00 × 107 particles/g and sizes of 16-110 nm. Ag2S NPs were the main form of AgCNPs in the examined soils with the percentage range of 53.98-69.19%, followed by AgCl NPs (11.42-23.31%) and Ag NPs (7.78-16.19%). Our method offers a new approach for evaluating the occurrence and potential risk of AgCNPs in environmental soils.
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Affiliation(s)
- Qingsheng Bai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingcun Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfu Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, Institute of Environment and Health, Jianghan University, Wuhan 430056, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
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Jiang H, Wang Y, Tan Z, Hu L, Shi J, Liu G, Yin Y, Cai Y, Jiang G. Dissolved metal ion removal by online hollow fiber ultrafiltration for enhanced size characterization of metal-containing nanoparticles with single-particle ICP-MS. J Environ Sci (China) 2023; 126:494-505. [PMID: 36503776 DOI: 10.1016/j.jes.2022.05.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 05/17/2022] [Accepted: 05/20/2022] [Indexed: 06/17/2023]
Abstract
Single particle-inductively coupled plasma mass spectrometry (SP-ICP-MS) is a powerful tool for size-characterization of metal-containing nanoparticles (MCNs) at environmentally relevant concentrations, however, coexisting dissolved metal ions greatly interfere with the accuracy of particle size analysis. The purpose of this study is to develop an online technique that couples hollow fiber ultrafiltration (HFUF) with SP-ICP-MS to improve the accuracy and size detection limit of MCNs by removing metal ions from suspensions of MCNs. Through systematic optimization of conditions including the type and concentration of surfactant and complexing agent, carrier pH, and ion cleaning time, HFUF completely removes metal ions but retains the MCNs in suspension. The optimal conditions include using a mixture of 0.05 vol.% FL-70 and 0.5 mmol/L Na2S2O3 (pH = 8.0) as the carrier and 4 min as the ion cleaning time. At these conditions, HFUF-SP-ICP-MS accurately determines the sizes of MCNs, and the results agree with the size distribution determined by transmission electron microscopy, even when metal ions also are present in the sample. In addition, reducing the ionic background through HFUF also lowers the particle size detection limit with SP-ICP-MS (e.g., from 28.3 to 14.2 nm for gold nanoparticles). This size-based ion-removal principle provided by HFUF is suitable for both cations (e.g., Ag+) and anions (e.g., AuCl4-) and thus has good versatility compared to ion exchange purification and promising prospects for the removal of salts and macromolecules before single particle analysis.
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Affiliation(s)
- Haowen Jiang
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ying Wang
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiqiang Tan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianbo Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guangliang Liu
- Department of Chemistry and Biochemistry, Florida International University, Miami 33199, USA
| | - Yongguang Yin
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China.
| | - Yong Cai
- Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Chemistry and Biochemistry, Florida International University, Miami 33199, USA
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Yu K, Yang X, Wan M, Jiang H, Shao P, Yang L, Shi H, Luo X. Effect of soil pH on thermally enhanced desorption of m-xylene by zero-valent iron particles under an electromagnetic field. JOURNAL OF HAZARDOUS MATERIALS 2023; 442:130019. [PMID: 36166910 DOI: 10.1016/j.jhazmat.2022.130019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 08/18/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
This study, for the first time, evaluates a novel method for the desorption of contaminants from soil that uses the heat generated by zero-valent iron (ZVI) under low-frequency electromagnetic fields (EMF), and elucidates the specific effects of soil pH upon the process. It was found that the temperature of soil mixed with ZVI could reach up to ∼60 °C within 20 min under the applied EMF, and after 60 min the residual fraction of m-xylene in soil decreased by 86.4% compared to no-ZVI soil. The most efficient desorption of m-xylene occurred at a soil of pH 5. Desorption was related to the net heating capacity of the ZVI particles, which was defined by pH-dependent formation of surface corrosion products. The preservation of metal iron and formation of Fe(II) species was favored for heat generation. Soil pH also affected m-xylene retention and the local thermal conduction from ZVI to m-xylene by regulating the surface properties of fulvic acid and ZVI. This study provides valuable information regarding the impact of pH on the thermal desorption of soil contaminants by ZVI coupled with EMF and illustrates the potential of the method in the remediation of contaminated sites.
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Affiliation(s)
- Kai Yu
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Xiuqiong Yang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Mao Wan
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Haowen Jiang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Penghui Shao
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Liming Yang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Hui Shi
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China
| | - Xubiao Luo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang, Jiangxi 330063, China.
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Li P, He C, Lin D. Extraction and quantification of polystyrene nanoplastics from biological samples. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120267. [PMID: 36174811 DOI: 10.1016/j.envpol.2022.120267] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/04/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Accurate quantification of nanoplastics (NPs) in complex matrices remains a challenge, especially for biological samples containing high content of organic matters. Herein, a new method extracting and quantifying polystyrene (PS) NPs from biological samples was developed. The extraction included alkaline digestion, centrifugation, and cloud point extraction (CPE), and the quantification included gold nanoparticles formation and labeling on surfaces of the extracted NPs and thereafter measurement with single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). Results show that 25% tetramethylammonium hydroxide solution was an effective alkaline digestion solution for biological matrices, and CPE after centrifugation (3000 rpm, 10 min) was applicable to purify and enrich PS NPs with different sizes (100 and 500 nm) and surface functionalities (-COOH and -NH2 modifications) from the digestion solution. The efficiency of Au labeling on PS NPs surface was improved by about 70% in the presence of 100 μM cetyltrimethylammonium bromide. The performance of the quantification method was examined by extraction and measurement of PS NPs spiked in four representative organism samples including bacteria, algae, nematode, and earthworm, and was further validated by analyzing the accumulated PS NPs in exposed nematodes. Good recovery rates (65 ± 10%-122 ± 22%) were achieved for spiking levels of 5-50 μg g-1; the limit of detection was 3.7 × 107 particles g-1, corresponding to the mass concentration of about 0.02 and 2.5 μg g-1 for the 100 nm and 500 nm PS NPs, respectively. The established extraction and quantification methods are efficient and sensitive, providing a useful approach for further exploring the environmental behavior and toxicity of NPs.
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Affiliation(s)
- Pei Li
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Hwa Mei Hospital, University of Chinese Academy of Science, Ningbo, 315010, China
| | - Caijiao He
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China
| | - Daohui Lin
- Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou, 310058, China.
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Liu S, Shen H, Gao C, Liu JH, Yu YL, Wang JH. Analysis of trace phytoavailable heavy metals in saline soil extract by one-step electroextraction coupled with in situ desorption microplasma optical emission spectrometry. Anal Chim Acta 2022; 1232:340497. [DOI: 10.1016/j.aca.2022.340497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 10/02/2022] [Accepted: 10/05/2022] [Indexed: 11/30/2022]
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Cai W, Wang Y, Feng Y, Liu P, Dong S, Meng B, Gong H, Dang F. Extraction and Quantification of Nanoparticulate Mercury in Natural Soils. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:1763-1770. [PMID: 35005907 DOI: 10.1021/acs.est.1c07039] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nanoparticulate mercury (Hg-NPs) are ubiquitous in nature. However, the lack of data on their concentration in soils impedes reliable risk assessments. This is due to the analytical difficulties resulting from low ambient Hg concentrations and background interferences of heterogeneous soil components. Here, coupled to single particle inductively coupled plasma-mass spectrometry (spICP-MS), a standardized protocol was developed for extraction and quantification of Hg-NPs in natural soils with a wide range of properties. High particle number-, particle mass-, and total mass-based recoveries were obtained for spiked HgS-NPs (74-120%). Indigenous Hg-NPs across soils were within 107-1011 NPs g-1, corresponding to 3-40% of total Hg on a mass basis. Metacinnabar was the primary Hg species in extracted samples from the Wanshan mercury mining site, as characterized by X-ray absorption spectroscopy and transmission electron microscopy. In agreement with the spICP-MS analysis, electron microscopy revealed comparable size distribution for nanoparticles larger than 27 nm. These indigenous Hg-NPs contributed to 5-65% of the measured methylmercury in soils. This work paves the way for experimental determinations of indigenous Hg-NPs in natural soils, which is critical to understand the biogeochemical cycling of mercury and thereby the methylation processes governing the public exposure to methylmercury.
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Affiliation(s)
- Weiping Cai
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yujun Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Feng
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Peng Liu
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Shuofei Dong
- Agilent Technologies Co., Ltd (China), Beijing 100102, China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
| | - Hua Gong
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Fei Dang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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