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Elizabeth George S, Wan Y. Microbial functionalities and immobilization of environmental lead: Biogeochemical and molecular mechanisms and implications for bioremediation. JOURNAL OF HAZARDOUS MATERIALS 2023; 457:131738. [PMID: 37285788 PMCID: PMC11249206 DOI: 10.1016/j.jhazmat.2023.131738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 05/26/2023] [Accepted: 05/28/2023] [Indexed: 06/09/2023]
Abstract
The increasing environmental and human health concerns about lead in the environment have stimulated scientists to search for microbial processes as innovative bioremediation strategies for a suite of different contaminated media. In this paper, we provide a compressive synthesis of existing research on microbial mediated biogeochemical processes that transform lead into recalcitrant precipitates of phosphate, sulfide, and carbonate, in a genetic, metabolic, and systematics context as they relate to application in both laboratory and field immobilization of environmental lead. Specifically, we focus on microbial functionalities of phosphate solubilization, sulfate reduction, and carbonate synthesis related to their respective mechanisms that immobilize lead through biomineralization and biosorption. The contributions of specific microbes, both single isolates or consortia, to actual or potential applications in environmental remediation are discussed. While many of the approaches are successful under carefully controlled laboratory conditions, field application requires optimization for a host of variables, including microbial competitiveness, soil physical and chemical parameters, metal concentrations, and co-contaminants. This review challenges the reader to consider bioremediation approaches that maximize microbial competitiveness, metabolism, and the associated molecular mechanisms for future engineering applications. Ultimately, we outline important research directions to bridge future scientific research activities with practical applications for bioremediation of lead and other toxic metals in environmental systems.
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Affiliation(s)
- S Elizabeth George
- US EPA Office of Research and Development, Center for Environmental Measurement and Modeling, Gulf Ecosystem Measurement and Modeling Division, One Sabine Island Drive, Gulf Breeze, FL 32561, USA
| | - Yongshan Wan
- US EPA Office of Research and Development, Center for Environmental Measurement and Modeling, Gulf Ecosystem Measurement and Modeling Division, One Sabine Island Drive, Gulf Breeze, FL 32561, USA.
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Gomes FP, Soares MB, de Carvalho HWP, Sharma A, Hesterberg D, Alleoni LRF. Zinc speciation and desorption kinetics in a mining waste impacted tropical soil amended with phosphate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 864:161009. [PMID: 36549526 DOI: 10.1016/j.scitotenv.2022.161009] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 11/29/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
Mining is an important component of the Brazilian economy. However, it may also contribute to environmental problems such as the pollution of soils with zinc and other potentially toxic metals. Our objective was to evaluate changes in the chemical speciation and mobility of Zn in a soil amended with phosphate. Soil samples were collected from a deactivated mining area in the state of Minas Gerais, Brazil, and amended with NH4H2PO4 saturated with deionized water to 70 % of maximum water retention and incubated at 25 ± 2 °C in open containers for 60 days. The soil was chemically and mineralogically characterized, and sequential extraction, desorption kinetics, and speciation were carried out using synchrotron bulk-sample and micro-X-ray Absorption Near-Edge Structure (XANES/μ-XANES) spectroscopy at the Zn K-edge, and X-ray fluorescence microprobe analysis (μ-XRF). The combination of μ-XRF and μ-XANES techniques made it possible to identify Zn hotspots in the main species formed after phosphate remediation. The best fit combination for bulk XANES and μ-XANES was observed in Zn-montmorillonite, Zn-kerolite, Zn-ferrihydrite, and gahnite. In the course of phosphate treatment, gahnite, Zn layered double hydroxides (Zn-LDH), Zn3(PO4), and ZnO were identified by bulk XANES, while Zn-ferrihydrite, Zn-montmorillonite, and scholzite were identified by μ-XANES. Zinc in the phosphate-amended soil had the strongest partial correlations (r' > 0.05) with Ni, Co, Fe, Cr, Mn, Si, P, Cd, Pb, and Cd, while the unamended soil showed the strongest correlation with Cu, Pb, Fe, and Si. The application of NH4H2PO4 altered Zn speciation and favored an increase in Zn desorption. The most available Zn contents after phosphate amendment were correlated with the release of exchangeable Zn fractions, associated with carbonate and organic matter.
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Affiliation(s)
- Frederico Prestes Gomes
- University of São Paulo, Luiz de Queiroz College of Agriculture, Av. Pádua Dias, 11, Piracicaba, São Paulo 13418-900, Brazil.
| | - Matheus Bortolanza Soares
- University of São Paulo, Luiz de Queiroz College of Agriculture, Av. Pádua Dias, 11, Piracicaba, São Paulo 13418-900, Brazil
| | | | - Aakriti Sharma
- Department of Soil Science, North Carolina State University, Raleigh, NC 27695, USA
| | - Dean Hesterberg
- Department of Soil Science, North Carolina State University, Raleigh, NC 27695, USA; Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil
| | - Luís Reynaldo Ferracciú Alleoni
- University of São Paulo, Luiz de Queiroz College of Agriculture, Av. Pádua Dias, 11, Piracicaba, São Paulo 13418-900, Brazil
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Li X, Zhou J, Zhou T, Li Z, Hu P, Luo Y, Christie P, Wu L. Potential mobilization of cadmium and zinc in soils spiked with smithsonite and sphalerite under different water management regimes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 324:116336. [PMID: 36162317 DOI: 10.1016/j.jenvman.2022.116336] [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: 07/11/2022] [Revised: 09/15/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
Particulate cadmium (Cd) and zinc (Zn) are ubiquitous in agricultural soils of Pb-Zn mining regions. Water management serves as an important agronomic measure altering the bioavailability of Zn and Cd in soils, but how this affects particulate Cd and Zn and the underlying mechanisms remain largely unknown. Microcosm soil incubation combined with spectroscopic and microscopic characterization was conducted. During a two-year-long incubation period we observed that the concentrations of soil CaCl2-extractable Zn and Cd increased 3-10 times in sphalerite-spiked soils and 1-2 times in smithsonite-spiked soils under periodic flooding conditions due to the long-term dissolution of sphalerite (SP) and smithsonite (SM). However, the increase in the concentration of CaCl2-extractable metals (Zn: from 0.607 mg kg-1 to 1.051 mg kg-1 and Cd: from 0.047 mg kg-1 to 0.119 mg kg-1) was found only in SP-treatment under continuous flooding conditions, indicating the mobilization of metals. Ultrafiltration analysis shows that the nanoparticulate fraction of Zn and Cd in soil pore water increased 5 and 7 times in SP-treatments under continuous flooding conditions, suggesting the increment of metal pools in soil pore water. HRTEM-EDX-SAED further reveals that these nanoparticles were mainly crystalline ZnS and Zn-bearing sulfate nanoparticles in the SP-treatment and amorphous ZnCO3 and ZnS nanoparticles in the SM-treatment. Therefore, the formation of the stable crystalline Zn-bearing nanoparticles in the SP-treatment may explain the elevation of the concentration of soil CaCl2-extractable Zn and Cd under continuous flooding. The potential mobility of particulate metals should therefore be expected in scenarios of continuous flooding such as paddy soils and wetland systems.
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Affiliation(s)
- Xinyang Li
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Jiawen Zhou
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Tong Zhou
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Zhu Li
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Pengjie Hu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Yongming Luo
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Peter Christie
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Longhua Wu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
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Newsome L, Falagán C. The Microbiology of Metal Mine Waste: Bioremediation Applications and Implications for Planetary Health. GEOHEALTH 2021; 5:e2020GH000380. [PMID: 34632243 PMCID: PMC8490943 DOI: 10.1029/2020gh000380] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 08/17/2021] [Accepted: 08/20/2021] [Indexed: 05/13/2023]
Abstract
Mine wastes pollute the environment with metals and metalloids in toxic concentrations, causing problems for humans and wildlife. Microorganisms colonize and inhabit mine wastes, and can influence the environmental mobility of metals through metabolic activity, biogeochemical cycling and detoxification mechanisms. In this article we review the microbiology of the metals and metalloids most commonly associated with mine wastes: arsenic, cadmium, chromium, copper, lead, mercury, nickel and zinc. We discuss the molecular mechanisms by which bacteria, archaea, and fungi interact with contaminant metals and the consequences for metal fate in the environment, focusing on long-term field studies of metal-impacted mine wastes where possible. Metal contamination can decrease the efficiency of soil functioning and essential element cycling due to the need for microbes to expend energy to maintain and repair cells. However, microbial communities are able to tolerate and adapt to metal contamination, particularly when the contaminant metals are essential elements that are subject to homeostasis or have a close biochemical analog. Stimulating the development of microbially reducing conditions, for example in constructed wetlands, is beneficial for remediating many metals associated with mine wastes. It has been shown to be effective at low pH, circumneutral and high pH conditions in the laboratory and at pilot field-scale. Further demonstration of this technology at full field-scale is required, as is more research to optimize bioremediation and to investigate combined remediation strategies. Microbial activity has the potential to mitigate the impacts of metal mine wastes, and therefore lessen the impact of this pollution on planetary health.
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Affiliation(s)
- Laura Newsome
- Camborne School of Mines and Environment and Sustainability InstituteUniversity of ExeterPenrynUK
| | - Carmen Falagán
- Camborne School of Mines and Environment and Sustainability InstituteUniversity of ExeterPenrynUK
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Kim SH, Jeong S, Chung H, Nam K. Contribution of precipitation and adsorption on stabilization of Pb in mine waste by basic oxygen furnace slag and the stability of Pb under reductive condition. CHEMOSPHERE 2021; 263:128337. [PMID: 33297263 DOI: 10.1016/j.chemosphere.2020.128337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/10/2020] [Accepted: 09/12/2020] [Indexed: 06/12/2023]
Abstract
A basic oxygen furnace (BOF) slag was used to stabilize lead (Pb) in a mine waste. Stabilization efficiencies differed depending on the slag contents (i.e., 3, 5, and 10 wt.%) and the water contents (i.e., 0.05-5.0 L/kg), varying from 52.2 to 98.0%, and both the slag contents and the water contents positively affected the stabilization efficiency. X-ray photoelectron spectroscopy suggested an evidence that precipitation and adsorption mechanisms were involved. When the contribution of each mechanism was determined, the increase in the BOF slag content mainly increased adsorption mechanism probably because of the increase in the adsorption sties. The increase in the water content, on the other hand, facilitated precipitation mechanism by lowering the ionic strength. Stabilized Pb could be mobilized at redox potential of 20-85 mV due to the reductive dissolution of Fe and Mn oxides. Sequential extraction results demonstrated that the adsorbed Pb became mobilized, and the fraction of exchangeable Pb increased.
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Affiliation(s)
- Sang Hyun Kim
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1 Gwanak-gu, Seoul, 08826, South Korea
| | - Seulki Jeong
- Seoul Center, Korea Basic Science Institute, 6-7 Inchon-ro 22-gil Seongbuk-gu, Seoul, 02855, South Korea
| | - Hyeonyong Chung
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1 Gwanak-gu, Seoul, 08826, South Korea
| | - Kyoungphile Nam
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1 Gwanak-gu, Seoul, 08826, South Korea.
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Abstract
Exposure to lead (Pb) during early life has persistent adverse health effects. During childhood, ingestion of bioavailable Pb in contaminated soils can be a major route of Pb absorption. Remediation to alter physiochemical properties of soil-borne Pb can reduce Pb bioavailability. Our laboratory-based approach for soil Pb remediation uses addition of iron (Fe) sulfate and application of heat to promote formation of plumbojarosite (PLJ), a sparingly soluble Pb-Fe hydroxysulfate mineral. We treated two soils with anthropogenic Pb contamination and samples of clean topsoil spiked with various Pb compounds (i.e., carbonate, chloride, phosphate [P], or sulfate) to convert native Pb species to PLJ and used a mouse assay to assess relative bioavailability (RBA) of Pb in untreated (U) and remediated soils. Bone and blood Pb levels were significantly lower (P < 0.001, Student's t test) in mice that consumed diets amended with remediated soils than with U soils. Estimated RBA for Pb in both remediated natural soils and Pb-mineral spiked soils were reduced by >90% relative to Pb RBA for U soils, which is substantially more effective than other soil amendments, including P. X-ray absorption spectroscopy showed that >90% of all Pb species in remediated soils were converted to PLJ, and ingested PLJ was not chemically transformed during gastrointestinal tract transit. Post treatment neutralization of soil pH did not affect PLJ stability, indicating the feasibility in field conditions. These results suggest that formation of PLJ in contaminated soils can reduce the RBA of Pb and minimize this medium's role as a source of Pb exposure for young children.
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Padoan E, Hernandez Kath A, Vahl LC, Ajmone-Marsan F. Potential Release of Zinc and Cadmium From Mine-Affected Soils Under Flooding, a Mesocosm Study. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2020; 79:421-434. [PMID: 33175188 PMCID: PMC7688597 DOI: 10.1007/s00244-020-00777-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/26/2020] [Indexed: 05/03/2023]
Abstract
Metal-contaminated mining soils pose serious environmental and health risks if not properly managed, especially in mountainous areas, which are more susceptible to perturbation. Currently, climate change is leading to more frequent and intense rain events, which cause flooding episodes, thereby altering soil redox equilibria and contaminants stability. We evaluated the potential release of Zn and Cd (two of the most common inorganic contaminants) and the factors regulating their solubility and speciation in two heavily contaminated soils representative of a Zn-mining area. The soils were flooded under aerobic (for 24 h) and anaerobic (for 62 days) conditions using mesocosm experiments, sequential extractions, and geochemical modelling. Leaching trials under aerobic conditions showed a high release of Zn and Cd (10 times the legislative limits), with metals possibly migrating via water infiltration or runoff. Under anaerobic conditions Zn and Cd were initially released. Then, solution concentrations decreased gradually (Zn) or sharply (Cd) until the end of the experiment. Sequential extractions and multisurface modelling indicated that both metals precipitated mainly as carbonates. This was confirmed by a geochemical multisurface modelling, which also predicted the formation of sulphides after 60 days in one soil. The model calculated metals to be preferentially complexed by organic matter and well predicted the observed soil solution concentrations. The results showed that during flooding episodes contaminants could be promptly transferred to other environmental compartments. The use of multisurface modelling coupled with laboratory experiments provided useful indications on the potential release and speciation in case of anoxic conditions.
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Affiliation(s)
- Elio Padoan
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi Di Torino, Largo Paolo Braccini 2, 10095, Torino, Grugliasco, Italy.
| | - Aline Hernandez Kath
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi Di Torino, Largo Paolo Braccini 2, 10095, Torino, Grugliasco, Italy
- Soil and Water Management and Conservation Program, University Federal of Pelotas, Pelotas, Brazil
| | - Ledemar Carlos Vahl
- Soil and Water Management and Conservation Program, University Federal of Pelotas, Pelotas, Brazil
| | - Franco Ajmone-Marsan
- Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università Degli Studi Di Torino, Largo Paolo Braccini 2, 10095, Torino, Grugliasco, Italy
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Li H, Xu H, Zhou S, Yu Y, Li H, Zhou C, Chen Y, Li Y, Wang M, Wang G. Distribution and transformation of lead in rice plants grown in contaminated soil amended with biochar and lime. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 165:589-596. [PMID: 30236921 DOI: 10.1016/j.ecoenv.2018.09.039] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 09/05/2018] [Accepted: 09/07/2018] [Indexed: 05/22/2023]
Abstract
This study aimed to investigate the effects of rice straw biochar and lime (RBL) on the remediation of lead (Pb)-contaminated soil and mitigation of Pb translocation in rice plants by using pot experiments. Lead-contaminated soil collected from a farmland near a Pb-zinc (Zn) mine, biochar, limestone powder, and indica rice (Oryza sativa L.) were used in the present study. The experimental treatments included: (1) control (CK), (2) 2.5% biochar (RB1), (3) 5% biochar (RB2), (4) 0.6% lime (L1), (5) 1.2% lime (L2), (6) 2.5% biochar + 0.6% lime (RBL1), and (7) 2.5% biochar + 1.2% lime (RBL2). The results revealed that the treatment with RBL was more efficient than the treatment with only biochar or lime in decreasing CaCl2-extractable Pb content in the soil by increasing soil pH and soluble sulfate content in the soil. Treatment with RBL reduced in the accumulation of Pb in the shoot of rice plants, this was mainly attributed to the decrease in the concentration of available Pb in the soil. The RBL2 treatment not only decreased the concentration of Pb in brown rice by 84.33% and Pb distribution in rice embryo, but also increased rice yield by 53.38% from that of the control. Further, unlike biochar treatment, RBL and lime treatments decreased the translocation of Pb in rice plants. The RBL treatment increased the proportion of Pb distributed in the cell wall and reduced the mobility of Pb in plant tissues. Thus, application of biochar and lime in combination is more effective than their individual application in reducing the availability of Pb in the soil and Pb accumulation in brown rice.
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Affiliation(s)
- Honghong Li
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; School of History and Geography, Minnan Normal University, Zhangzhou 363000, PR China
| | - Hao Xu
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Shi Zhou
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yong Yu
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Hailong Li
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Cui Zhou
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yanhui Chen
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yunyun Li
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Mingkuang Wang
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Guo Wang
- College of Resource and Environmental Science, Soil Environmental Health and Regulation, Key Laboratory of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
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Kim SH, Jeong S, Chung H, Nam K. Stabilization mechanism of arsenic in mine waste using basic oxygen furnace slag: The role of water contents on stabilization efficiency. CHEMOSPHERE 2018; 208:916-921. [PMID: 30068035 DOI: 10.1016/j.chemosphere.2018.05.173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 05/15/2018] [Accepted: 05/27/2018] [Indexed: 06/08/2023]
Abstract
Arsenic stabilization mechanism in a mine waste was investigated using a basic oxygen furnace (BOF) slag. A lab-scale batch test was carried out to stabilize As in the mine waste samples for 1 h, where various amounts of the BOF slag and distilled water were introduced. Different stabilization efficiencies were observed depending on the stabilizing conditions (i.e., BOF slag content and water to mine waste (L/S) ratio). The stabilization efficiencies ranged 75-92% and 92-95% for 5% (w-slag/w-mine waste) and 10% BOF slag treated mine waste samples, respectively. Interestingly, a notable effect of the L/S ratio on the stabilization efficiency was observed (78% at 0.05 L/kg, and 23% at 1.0 L/kg) at the 3% BOF slag treatment. The point of zero charge and the stabilizing pH indicated that the BOF slag surface was negatively charged. Based on the comparison of fresh and Ca-reduced BOF slags, As stabilization mechanism was determined to be adsorption through cation bridges by Ca2+. The Surface analysis using X-ray photoelectron spectroscopy (XPS) and the stabilization experiment conducted at lower pH provided evidence that the hindrance of As adsorption resulted from Ca(OH)2 precipitation on the BOF slag surface when excess water (1.0 L/kg) was added. Such effect of water content seemed to be overcome by providing an excessive amount of the BOF slag. When an ample amount of Ca2+ is provided and pH is maintained around 11, not only As adsorption but also calcium arsenate precipitation occur, and both contributed to the stabilization mechanisms of As.
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Affiliation(s)
- Sang Hyun Kim
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, South Korea
| | - Seulki Jeong
- Seoul Center, Korea Basic Science Institute, 6-7, Inchon-ro 22-gil, Seongbuk-gu, Seoul, 02855, South Korea
| | - Hyeonyong Chung
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, South Korea
| | - Kyoungphile Nam
- Department of Civil and Environmental Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, South Korea.
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10
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Karna RR, Noerpel MR, Luxton TP, Scheckel KG. Point of zero charge: Role in pyromorphite formation and bioaccessibility of lead and arsenic in phosphate amended soils. SOIL SYSTEMS 2018; 2:22. [PMID: 30714024 DOI: 10.3390/soilsystems2020022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Soluble lead (Pb) can be immobilized in pure systems as pyromorphite by adding sources of phosphorus (P), but uncertainties still remain in natural systems. Knowledge of PZC is important to predict the ionization of functional groups and their interaction with metal species in solution. This study utilized the Pb- and As-contaminated soils to determine the combined effect of pH with respect to PZC and different rates of P-application on pyromorphite formation, and Pb and arsenic (As) bioaccessibility as impacted by speciation changes. Solution chemistry analysis along with synchrotron-based Pb- and As-speciation, and bioaccessibility treatment effect ratios (TERs) were conducted. Results indicated no significant effect of PZC on pyromorphite formation in P-amended soils; however, the TERPb appeared significantly lower at pH>pHPZC and higher at pH<pHPZC (α = 0.05). In contrast, the TERAs was significantly higher at pH>pHPZC, compared to the other two treatments, for the tested soils. The lack of conversion of soil Pb to pyromorphite may be attributed to presence of stable minerals limiting soluble-Pb availability and high organic matter content of the tested soils.
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Affiliation(s)
- Ranju R Karna
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
- United States Environmental Protection Agency, National Risk Management Research Laboratory, Cincinnati, OH 45224, USA
| | - Matthew R Noerpel
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
- United States Environmental Protection Agency, National Risk Management Research Laboratory, Cincinnati, OH 45224, USA
| | - Todd P Luxton
- United States Environmental Protection Agency, National Risk Management Research Laboratory, Cincinnati, OH 45224, USA
| | - Kirk G Scheckel
- United States Environmental Protection Agency, National Risk Management Research Laboratory, Cincinnati, OH 45224, USA
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Paredez JM, Mladenov N, Galkaduwa MB, Hettiarachchi GM, Kluitenberg GJ, Hutchinson SL. A soil column study to evaluate treatment of trace elements from saline industrial wastewater. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2017; 76:2698-2709. [PMID: 29168710 DOI: 10.2166/wst.2017.413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Industrial wastewater from the flue gas desulfurization (FGD) process is characterized by the presence of trace elements of concern, such as selenium (Se) and boron (B) and relatively high salinity. To simulate treatment that FGD wastewater undergoes during transport through soils in subsurface treatment systems, a column study (140-d duration) was conducted with native Kansas soil and saline FGD wastewater, containing high Se and B concentrations (170 μg/L Se and 5.3 mg/L B) and negligible arsenic (As) concentration (∼1.2 μg/L As). Se, B, and As, and dissolved organic carbon concentrations and organic matter spectroscopic properties were measured in the influent and outflow. Influent Se concentrations were reduced by only ∼half in all treatments, and results suggest that Se sorption was inhibited by high salinity of the FGD wastewater. By contrast, relative concentrations (C/Co) of B in the outflow were typically <10%, suggesting that B sequestration may have been enhanced by higher salinity. Unexpected elevated As concentrations in the outflow (at >150 μg/L in the treatment with labile organic carbon addition) suggest that soils not previously known to be geogenic arsenic sources have the potential to release As to groundwater in the presence of high salinity wastewater and under reducing conditions.
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Affiliation(s)
- Jose M Paredez
- Department of Civil Engineering, Kansas State University, 2118 Fiedler Hall, Manhattan, KS 66506, USA
| | - Natalie Mladenov
- Department of Civil, Construction, and Environmental Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA E-mail:
| | - Madhubhashini B Galkaduwa
- Department of Agronomy, Kansas State University, Throckmorton Plant Sciences Center, 1712 Claflin Rd, Manhattan, KS 66506, USA
| | - Ganga M Hettiarachchi
- Department of Agronomy, Kansas State University, Throckmorton Plant Sciences Center, 1712 Claflin Rd, Manhattan, KS 66506, USA
| | - Gerard J Kluitenberg
- Department of Agronomy, Kansas State University, Throckmorton Plant Sciences Center, 1712 Claflin Rd, Manhattan, KS 66506, USA
| | - Stacy L Hutchinson
- Department of Biological and Agricultural Engineering, Kansas State University, Seaton Hall, 920 N. 17th St., Manhattan, KS 66506, USA
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Sutton SR, Lanzirotti A, Newville M, Rivers ML, Eng P, Lefticariu L. Spatially Resolved Elemental Analysis, Spectroscopy and Diffraction at the GSECARS Sector at the Advanced Photon Source. JOURNAL OF ENVIRONMENTAL QUALITY 2017; 46:1158-1165. [PMID: 29293842 DOI: 10.2134/jeq2016.10.0401] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
X-ray microprobes (XRM) coupled with high-brightness synchrotron X-ray facilities are powerful tools for environmental biogeochemistry research. One such instrument, the XRM at the Geo Soil Enviro Center for Advanced Radiation Sources Sector 13 at the Advanced Photon Source (APS; Argonne National Laboratory, Lemont, IL) was recently improved as part of a canted undulator geometry upgrade of the insertion device port, effectively doubling the available undulator beam time and extending the operating energy of the branch supporting the XRM down to the sulfur K edge (2.3 keV). Capabilities include rapid, high-resolution, elemental imaging including fluorescence microtomography, microscale X-ray absorption fine structure spectroscopy including sulfur K edge capability, and microscale X-ray diffraction. These capabilities are advantageous for (i) two-dimensional elemental mapping of relatively large samples at high resolution, with the dwell times typically limited only by the count times needed to obtain usable counting statistics for low concentration elements, (ii) three-dimensional imaging of internal elemental distributions in fragile hydrated specimens, such as biological tissues, avoiding the need for physical slicing, (iii) spatially resolved speciation determinations of contaminants in environmental materials, and (iv) identification of contaminant host phases. In this paper, we describe the XRM instrumentation, techniques, applications demonstrating these capabilities, and prospects for further improvements associated with the proposed upgrade of the APS.
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Hettiarachchi GM, Donner E, Doelsch E. Application of Synchrotron Radiation-based Methods for Environmental Biogeochemistry: Introduction to the Special Section. JOURNAL OF ENVIRONMENTAL QUALITY 2017; 46:1139-1145. [PMID: 29293855 DOI: 10.2134/jeq2017.09.0349] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
To understand the biogeochemistry of nutrients and contaminants in environmental media, their speciation and behavior under different conditions and at multiple scales must be determined. Synchrotron radiation-based X-ray techniques allow scientists to elucidate the underlying mechanisms responsible for nutrient and contaminant mobility, bioavailability, and behavior. The continuous improvement of synchrotron light sources and X-ray beamlines around the world has led to a profound transformation in the field of environmental biogeochemistry and, subsequently, to significant scientific breakthroughs. Following this introductory paper, this special collection includes 10 papers that either present targeted reviews of recent advancements in spectroscopic methods that are applicable to environmental biogeochemistry or describe original research studies conducted on complex environmental samples that have been significantly enhanced by incorporating synchrotron radiation-based X-ray technique(s). We believe that the current focus on improving the speciation of ultra-dilute elements in environmental media through the ongoing optimization of synchrotron technologies (e.g., brighter light sources, improved monochromators, more efficient detectors) will help to significantly push back the frontiers of environmental biogeochemistry research. As many of the relevant techniques produce extremely large datasets, we also identify ongoing improvements in data processing and analysis (e.g., software improvements and harmonization of analytical methods) as a significant requirement for environmental biogeochemists to maximize the information that can be gained using these powerful tools.
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Karna RR, Noerpel M, Betts AR, Scheckel KG. Lead and Arsenic Bioaccessibility and Speciation as a Function of Soil Particle Size. JOURNAL OF ENVIRONMENTAL QUALITY 2017; 46:1225-1235. [PMID: 29293839 PMCID: PMC5868743 DOI: 10.2134/jeq2016.10.0387] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/12/2017] [Indexed: 05/04/2023]
Abstract
Bioavailability research of soil metals has advanced considerably from default values to validated in vitro bioaccessibility (IVBA) assays for site-specific risk assessment. Previously, USEPA determined that the soil-size fraction representative of dermal adherence and consequent soil ingestion was <250 μm. This size fraction was widely used in testing efforts for both in vivo and in vitro experiments. However, recent studies indicate the <150-μm size fraction better represents the particle size that adheres to skin for potential ingestion. At issue is the relevance of validated in vivo and in vitro methods developed with <250 μm moving to the <150-μm fraction. The objectives of this study were to investigate <250-μm versus <150-μm particle size and particle size groups for evaluating lead (Pb) and arsenic (As) IVBA and speciation. Soils with different properties were homogenized, oven dried, and sieved: <250 to > 150, <150 to >75, <75 to >38, and <38 μm. Sieved versus ground subsamples of <250-μm and <150-μm bulk soils were also used for IVBA and synchrotron-based Pb and As speciation. Although we observed an increase in total and IVBA-extractable Pb and As with decreased soil particle size, changes in %IVBA of Pb and As (dependent on the ratio extractable:total) remained consistent in all of the tested soils. No significant changes in Pb and As speciation were observed across the soil fractions. The results suggest that using the more relevant <150-μm fraction will not undermine currently validated IVBA protocols in future bioavailability studies.
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Affiliation(s)
- Ranju R. Karna
- Research Participant, Oak Ridge Institute of Science and Education, National Risk Management Research Laboratory-Land Remediation and Pollution Control Division, 5995 Center Hill Avenue, Cincinnati, OH 45224-1701
| | - Matt Noerpel
- Research Participant, Oak Ridge Institute of Science and Education, National Risk Management Research Laboratory-Land Remediation and Pollution Control Division, 5995 Center Hill Avenue, Cincinnati, OH 45224-1701
| | - Aaron R. Betts
- Research Participant, Oak Ridge Institute of Science and Education, National Risk Management Research Laboratory-Land Remediation and Pollution Control Division, 5995 Center Hill Avenue, Cincinnati, OH 45224-1701
- Graduate Student, Department of Soil and Plant Sciences, University of Delaware, 221 Academy St., Newark, DE-19711
| | - Kirk G. Scheckel
- Senior Research Soil Scientist, United States Environmental Protection Agency, National Risk Management Research Laboratory-Land Remediation and Pollution Control Division, 5995 Center Hill Avenue, Cincinnati, OH 45224-1701
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