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Wei W, Liu Q, Zhang Z, Lisak G, Yin K, Fei X. Categorization of leaching behaviors of elements from commercially treated incineration bottom ash in Singapore. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 178:339-350. [PMID: 38430748 DOI: 10.1016/j.wasman.2024.02.045] [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: 09/04/2023] [Revised: 02/24/2024] [Accepted: 02/25/2024] [Indexed: 03/05/2024]
Abstract
Leaching of potentially hazardous substances, especially the heavy metals from Incineration Bottom Ash (IBA) is a major problem in its recyclable usage. To address this concern, treatment of IBA is indispensable before it can be reused. IBA subjected to laboratory-scale treatment typically yields clearer conclusions in terms of leaching behaviors, benefiting from the controlled laboratory environment. However, the leaching behaviors of commercially treated IBA appear to be more ambiguous due to the complex and comprehensive nature of industrial-scale treatments, where multiple treatment techniques are involved concurrently. Furthermore, treatment efficiencies vary among different plants. In this study, three types of commercially treated IBA were sampled from leading waste treatment companies in Singapore. Characterization and leaching tests were performed on the treated IBAs in both standardized and modified manners to simulate various scenarios. Besides deionized water, artificial seawater was used as a leachant in leaching tests for simulating seawater intrusion. The results reveal the promoting effect of seawater on the leaching levels of several elements from three types of treated IBA, which may require special attention for IBA application and landfill near the coast. Furthermore, the elements examined in these three types of commercially treated IBA generally comply with the non-hazardous waste acceptance criteria outlined in Council Decision, 2003/33/EC (2003), except Sb. By combining two leaching tests, the elements were categorized into different types of leaching behavior, making it possible to prepare and respond to the concerning leaching scenarios in future engineering applications.
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Affiliation(s)
- Wei Wei
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore; Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, 1 Cleantech Loop, 637141, Singapore
| | - Qian Liu
- Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, 1 Cleantech Loop, 637141, Singapore
| | - Zhibo Zhang
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Grzegorz Lisak
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore; Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, 1 Cleantech Loop, 637141, Singapore
| | - Ke Yin
- School of Biology and the Environment, Nanjing Forestry University, 159 Longpan Road, Nanjing 210037, China
| | - Xunchang Fei
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore; Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, 1 Cleantech Loop, 637141, Singapore.
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Hua J, Lundqvist M, Naidu S, Ekvall MT, Cedervall T. Environmental risks of breakdown nanoplastics from synthetic football fields. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 347:123652. [PMID: 38447657 DOI: 10.1016/j.envpol.2024.123652] [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: 12/28/2023] [Revised: 02/14/2024] [Accepted: 02/23/2024] [Indexed: 03/08/2024]
Abstract
The widespread use of synthetic turf in sports has raised health concerns due to potential risks from nanoplastic inhalation or ingestion. Our research focused on detecting nanoplastics in drainage water from a synthetic football field and evaluating the toxicity of these materials after mechanical fragmentation. We collected and analysed drainage water samples for polymer content and subjected high-density polyethylene (HDPE) straws and ethylene propylene diene monomer (EPDM) granules used on synthetic football fields, to mechanical breakdown to create nanoplastics. The results indicated the presence of trace amounts of EPDM in the water samples. Furthermore, the toxicological assessment revealed that the broken-down nanoplastics and leachate from the surface of EPDM rubber granules exhibited high toxicity to Daphnia magna, while nanoplastics from the inner material exhibited no significant toxicity. The findings highlight the urgent need for future research to identify these specific toxic agents from the surface of EPDM granules.
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Affiliation(s)
- Jing Hua
- Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden; NanoLund, Lund University, Lund, Sweden
| | - Martin Lundqvist
- Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden; NanoLund, Lund University, Lund, Sweden
| | - Shanti Naidu
- Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden
| | - Mikael T Ekvall
- NanoLund, Lund University, Lund, Sweden; Aquatic Ecology, Department of Biology, Lund University, Lund, Sweden
| | - Tommy Cedervall
- Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden; NanoLund, Lund University, Lund, Sweden.
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Wang S, Wei J, Zheng Z, Wu J, Xu J, Xie H. Transport of dimethyl phthalate on loess with modified bentonite: A batch and column test investigation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:162962. [PMID: 36958554 DOI: 10.1016/j.scitotenv.2023.162962] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 02/19/2023] [Accepted: 03/16/2023] [Indexed: 05/17/2023]
Abstract
Phthalic acid ester (PAE) is a toxic pollutant commonly found in high concentrations in municipal solid waste landfills. Soil-bentonite is widely used as a barrier material to control groundwater contaminants from landfill leachates. Traditional soil-bentonite materials always have a limited capacity for organic pollutant adsorption. To address this issue, the adsorption and transport behavior of dimethyl phthalate (DMP) on loess amended with two kinds of modified bentonite (HTMAC-B, modified with hexadecyltrimethylammonium chloride; CMC-B, modified with hydrophobic cationic surfactant, and carboxymethyl cellulose) were investigated. The kinetics of DMP adsorption indicates that film diffusion contributes significantly to the kinetic adsorption of DMP on HTMAC-B. The adsorption isotherm results showed that partitioning dominated DMP adsorption on loess with both modified bentonites. Owing to the in-ionic sites in HTMAC-B, which attracted hydrophobic compounds such as DMP, the adsorption capacity of 5 % HTMAC-B-amended loess (LH) was increased by a factor of 3.2. However, because CMC-B provided mostly ionic sites, 5 % CMC-B-amended loess (LC) had a little effect on DMP adsorption. The hydraulic conductivity values of LH and LC were 5.95 × 10-10 and 1.65 × 10-11 m/s, respectively. The X-CT result showed that there is a significant porosity change for both LH and LC. Dual-porosity model reveals that the leaching process primarily affects micro-pores, rather than larger pores in the soil matrix. The predicted retardation factors for LH and LC were 38.89 and 9.67, respectively. When using loess-bentonite as barrier material, the amendment of HTMAC-B and CMC-B can help to increase the retardation ability and reduce the permeability, respectively.
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Affiliation(s)
- Shaoyi Wang
- Power China Huadong Engineering Corporation Limited, Hangzhou 311122, China; Huadong Eco-Environmental Engineering Research Institute of Zhejiang Province, Hangzhou 310058, China
| | - Jun Wei
- Power China Huadong Engineering Corporation Limited, Hangzhou 311122, China; Huadong Eco-Environmental Engineering Research Institute of Zhejiang Province, Hangzhou 310058, China
| | - Zijing Zheng
- Power China Huadong Engineering Corporation Limited, Hangzhou 311122, China
| | - Jiawei Wu
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China
| | - Jianqiang Xu
- Power China Huadong Engineering Corporation Limited, Hangzhou 311122, China
| | - Haijian Xie
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China.
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Federico L, Masseroni A, Rizzi C, Villa S. Silent Contamination: The State of the Art, Knowledge Gaps, and a Preliminary Risk Assessment of Tire Particles in Urban Parks. TOXICS 2023; 11:toxics11050445. [PMID: 37235259 DOI: 10.3390/toxics11050445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/18/2023] [Accepted: 05/04/2023] [Indexed: 05/28/2023]
Abstract
Tire particles (TPs) are one of the main emission sources of micro- and nano-plastics into the environment. Although most TPs are deposited in the soil or in the sediments of freshwater and although they have been demonstrated to accumulate in organisms, most research has focused on the toxicity of leachate, neglecting the potential effects of particles and their ecotoxicological impact on the environment. In addition, studies have focused on the impact on aquatic systems and there are many gaps in the biological and ecotoxicological information on the possible harmful effects of the particles on edaphic fauna, despite the soil ecosystem becoming a large plastic sink. The aim of the present study is to review the environmental contamination of TPs, paying particular attention to the composition and degradation of tires (I), transport and deposition in different environments, especially in soil (II), the toxicological effects on edaphic fauna (III), potential markers and detection in environmental samples for monitoring (IV), preliminary risk characterization, using Forlanini Urban Park, Milan (Italy), as an example of an urban park (V), and risk mitigation measures as possible future proposals for sustainability (VI).
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Affiliation(s)
- Lorenzo Federico
- Department of Earth and Environmental Sciences DISAT, University of Milano-Bicocca, Piazza della Scienza 1, 20126 Milano, Italy
| | - Andrea Masseroni
- Department of Earth and Environmental Sciences DISAT, University of Milano-Bicocca, Piazza della Scienza 1, 20126 Milano, Italy
| | - Cristiana Rizzi
- Department of Earth and Environmental Sciences DISAT, University of Milano-Bicocca, Piazza della Scienza 1, 20126 Milano, Italy
| | - Sara Villa
- Department of Earth and Environmental Sciences DISAT, University of Milano-Bicocca, Piazza della Scienza 1, 20126 Milano, Italy
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Kubota R, Obama T, Kawakami T, Sakai S, Inoue K, Ikarashi Y. Characterization of synthetic turf rubber granule infill in Japan: Total content and migration of metals. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156705. [PMID: 35716741 DOI: 10.1016/j.scitotenv.2022.156705] [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: 04/08/2022] [Revised: 06/07/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
We evaluated the total content of 28 metals in synthetic turf rubber granule infill and performed extraction tests using four types of simulated biofluids to assess the health effects of synthetic turf crumb rubbers used in Japan. The highest median metal concentration was obtained for Zn, with median concentrations above 100 μg/g, followed by Al, Fe, and Mn. The highest median Pb concentration was 19.9 μg/g. The metal concentrations of the samples were different depending on the origin/material. Among high-concentration metals, Al, Fe, and Mn were higher in ethylene propylene diene monomer rubber, and Zn was higher in tires. Significantly higher Sb and Sr concentrations were observed in other materials, including industrial rubber, synthetic rubber, and thermoplastic elastomer, compared with tires. However, significantly higher Sn, Co, Pb, and Cd concentrations were detected in tires compared with other materials. Metals with high concentrations independent of the origin/material were considered derived from materials added during the manufacturing process. To evaluate the bioaccessibility, extraction tests were conducted using simulated biofluids. In gastric fluid, many metals were detected in higher concentrations than in other biofluids, intestinal fluid, saliva, and sweat, and the extraction rate of most metals exceeded 10% in artificial gastric fluid. Because the amount of metals leached into the simulated biofluids was much lower than several standards on the amount of certain metals that have the potential to be extracted from the object if ingested, the risk related to the exposure to metals from synthetic turf rubber granule infill is considered low.
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Affiliation(s)
- Reiji Kubota
- Division of Environmental Chemistry, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan.
| | - Tomoko Obama
- Division of Environmental Chemistry, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Tsuyoshi Kawakami
- Division of Environmental Chemistry, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Shinobu Sakai
- Division of Environmental Chemistry, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Kaoru Inoue
- Division of Risk Assessment, Biological Safety Research Center, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Yoshiaki Ikarashi
- Division of Environmental Chemistry, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
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6
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Müller K, Hübner D, Huppertsberg S, Knepper TP, Zahn D. Probing the chemical complexity of tires: Identification of potential tire-borne water contaminants with high-resolution mass spectrometry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149799. [PMID: 34450436 DOI: 10.1016/j.scitotenv.2021.149799] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Tire wear particles are not only the type of polymer particles most prevalent in the environment but also act as source of various organic micropollutants, many of which are likely still unknown. We extracted particles prepared from nine tires in artificial freshwater (28 d) with the goal to characterize leachables (max intensity >105 in artificial freshwater), which are tire-borne water contaminants. A subsequent extraction of these particles with acetone (3 h) was used to assess the long-term leaching potential. A suspect and nontarget screening in aliquots of each extract led to the detection of 214 organic substances of which 145 were classified as leachables. The intrinsic polarity of some leachables (mean log D (pH 7.4) 3.9), which facilitates an increased aquatic mobility, highlights their potential as environmental water contaminants. With N,N'-diphenylguanidine (DPG) and benzothiazole, two of the ten unequivocally identified leachables, are classified as potential persistent, mobile and toxic substance by the German Environment Agency. Of the identified chemicals DPG showed the highest intensities in aqueous extracts and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6-PPD), the precursor of 6-PPD-quinone, in acetone extracts. A comparison between the 69 detected suspects and 174 high-intensity signals (>106) detected in the nontarget screening led to an overlap of only 29 features. A detailed investigation of the remaining high-intensity suspects revealed the presence of 13 proposed DPG reaction products, further highlighting the chemical complexity of tires. Consequently, we conclude that there are many, often still unrecognized chemicals entering the aquatic environment through leaching from tire wear particles.
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Affiliation(s)
- Kathrin Müller
- Hochschule Fresenius gem. GmbH, Limburger Str.2, 65510 Idstein, Germany
| | - Daniel Hübner
- Hochschule Fresenius gem. GmbH, Limburger Str.2, 65510 Idstein, Germany
| | - Sven Huppertsberg
- Hochschule Fresenius gem. GmbH, Limburger Str.2, 65510 Idstein, Germany
| | - Thomas P Knepper
- Hochschule Fresenius gem. GmbH, Limburger Str.2, 65510 Idstein, Germany
| | - Daniel Zahn
- Hochschule Fresenius gem. GmbH, Limburger Str.2, 65510 Idstein, Germany.
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7
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Distribution and Health Risk Assessment of Some Trace Elements in Runoff from Different Types of Athletic Fields. J CHEM-NY 2021. [DOI: 10.1155/2021/5587057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Environmental risk of heavy metals and metalloids in athletic fields has raised people’s attention in the recent years. Seven trace elements, including metals and metalloids, were detected in the runoff of five typical athletic fields in the university campus under three rainfall events. Except for Cr, the total concentrations of Zn, Pb, Cu, Mn, Cd, and As in artificial turf runoff are the highest among five athletic fields, followed by that of plastic runway. The concentration and first flush effect of trace elements are followed in the order of 1st > 2nd > 3rd rainfall events. The strongest correlations between metals and metalloids were observed in the tennis court runoff, while the artificial turf shows the least. The release of trace elements could be directly from the surface materials and particles on the athletic field and influenced by the comprehensive factors including surface materials, rainfall events, and pollutant characters. Pollution risk assessment shows that the pollution extent of the five types of athletic field is at least “moderate” and follows the order of artificial turf > basketball court > plastic runway > badminton court > tennis court. Pb shows the highest pollution level, while Cr shows the highest healthy risk. The results can provide a theoretical basis for runoff pollution control and safety use of athletic fields.
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Wang Y, Xu Y, Liang X, Sun Y, Huang Q, Peng Y. Leaching behavior and efficiency of cadmium in alkaline soil by adding two novel immobilization materials. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 710:135964. [PMID: 31926408 DOI: 10.1016/j.scitotenv.2019.135964] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
The seriousness and harmfulness of cadmium (Cd) pollution have been gradually attracting wide attention. Remediation materials currently play a critical role in the remediation of Cd-polluted soils. However, the amendments that can efficiently remediate Cd-polluted alkaline soils are relatively few. In this study, a column leaching experiment was conducted to determine the effects of mercapto-palygorskite (MPAL) and mercapto-sepiolite (MSEP) on the leaching behavior and chemical fraction distribution of heavy metals, and to explore the remediation efficiency of two novel materials in alkaline soils through aging experiments. The results showed that, under DTPA-assisted leaching, the maximum concentration of leachate Cd in MPAL and MSEP was below 1/30 (0.1 mg·kg-1) of the total Cd concentration among leaching and significantly lower than that in CK, palygorskite (PAL), and sepiolite (SEP) treatments. Meanwhile, MPAL and MSEP decreased the leaching efficiency of Cd stability, had negligible effects on the essential micronutrients Cu and Zn, and did not influence the pH and electrical conductivity (EC) values of leachate. After leaching, the Fe/Mn oxide-bound Cd increased in MPAL and MSEP, whereas the exchange fraction Cd and carbonate-bound Cd decreased. Aging results showed that MPAL and MSEP effectively reduced 62.39% and 44.89% of DTPA-Cd after 1 day of aging, while at same dosage (0.3%) PAL and SEP reduced 7.79% and 6.75% of DTPA-Cd after 30 days of aging and showed no obvious efficiency. It was thus concluded that MPAL and MSEP can be considered as two novel and efficient soil remediation materials for Cd-polluted alkaline soils.
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Affiliation(s)
- Yale Wang
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China; Key Laboratory of Original Environmental Pollution Control, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China
| | - Yingming Xu
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China; Key Laboratory of Original Environmental Pollution Control, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China.
| | - Xuefeng Liang
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China; Key Laboratory of Original Environmental Pollution Control, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China
| | - Yuebing Sun
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China; Key Laboratory of Original Environmental Pollution Control, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China
| | - Qingqing Huang
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China; Key Laboratory of Original Environmental Pollution Control, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China
| | - Yunying Peng
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China; Key Laboratory of Original Environmental Pollution Control, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin 300191, People's Republic of China
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9
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Zhai H, Xue M, Du Z, Wang D, Zhou F, Feng P, Liang DL. Leaching behaviors and chemical fraction distribution of exogenous selenium in three agricultural soils through simulated rainfall. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 173:393-400. [PMID: 30797097 DOI: 10.1016/j.ecoenv.2019.02.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 02/03/2019] [Accepted: 02/13/2019] [Indexed: 06/09/2023]
Abstract
To clarify the leaching risk of selenium (Se) in agricultural soils, a laboratory column experiment was conducted to study the characteristics of leaching and chemical fractions of Se in three different soils treated with different levels of exogenous selenate under simulated local rainfall. Results demonstrated that the Se concentration in leachates of all tested soils decreased rapidly at the beginning of leaching and slowly decreased thereafter. After leaching, Se concentrations in leachates of all tested soils at 1, 3, and 6 mg/kg exogenous Se concentrations were 0.06-0.24, 0.25-0.84, and 0.60-1.65 mg/L, respectively, which exceeded the standard limit of the Chinese Environmental Quality Standards for Groundwater (<0.01 mg/L) (GB/T 14848-2017). The cumulative leached Se amount accounted for 51.27-86.22% of the total Se. Those results indicated the high risk of Se leaching in the tested soils. The Elovich model could better describe Se leaching processes in krasnozem, while the leaching processes of Se in black soil and loess soil accorded with the power function model. Se mainly existed in soluble fraction (61.33-81.05%) before leaching and residual fraction (48.91-68.04%) after leaching. The soluble and exchangeable Se fractions were the main contributors of Se in leachates. In addition, the parameters of the Uts and IR values could well describe the distribution of Se fractions in soil during leaching. In general, more attention should be placed on the assessment of Se leaching in soil.
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Affiliation(s)
- Hui Zhai
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Mingyue Xue
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Zekun Du
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Dan Wang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Fei Zhou
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Puyang Feng
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Dong-Li Liang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi 712100, China.
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10
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Zou Q, Gao Y, Yi S, Jiang J, Aihemaiti A, Li D, Yang M. Multi-step column leaching using low-molecular-weight organic acids for remediating vanadium- and chromium-contaminated soil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:15406-15413. [PMID: 30941713 DOI: 10.1007/s11356-019-04915-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 03/19/2019] [Indexed: 06/09/2023]
Abstract
In soil, vanadium (V) contamination is commonly concomitant with chromium (Cr) contamination, which poses potential risks to humans, animals, and plants due to the transfer of toxic metals and the increase in their concentrations via the food chain or through direct exposure. This study applied a multi-step column leaching process using low-molecular-weight organic acids (LMWOAs) to treat V-contaminated soil from a smelter site that contains 2015.1 mg V kg-1 and 1060.3 mg Cr kg-1. After leaching three times with an equivalent solution/soil ratio of 0.3 mL/g using 1.0 M oxalic acid solution, the total removal rates reached 77.2% and 7.2% for V and Cr, respectively, while the removal rates of the extractable fractions reached 118.6% and 99.2% due to the reduction in residual fraction (F4) of toxic metals. Simultaneously, the distribution and redistribution of geochemical fractions of V and Cr were determined with a sequential extraction technique, and the greater proportion of potential mobile fractions of V (65.1%) may increase its leaching from soil relative to Cr (7.1%). In addition, a lower pH of the leaching agent increased the efficiency of the leaching process to an extent. Compared with batch extraction with a typical solution to soil ratio of 10 mL/g, multi-step column leaching used less agent and hence produced less wastewater. This strategy could reduce the mobilization and bioavailability of toxic metals, and potentially enhance in situ soil flushing for the remediation of V- and Cr- contaminated soil.
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Affiliation(s)
- Quan Zou
- School of Environment, Tsinghua University, Beijing, 10084, China.
| | - Yuchen Gao
- School of Environment, Tsinghua University, Beijing, 10084, China
| | - Soyoung Yi
- School of Environment, Tsinghua University, Beijing, 10084, China
| | - Jianguo Jiang
- School of Environment, Tsinghua University, Beijing, 10084, China.
| | | | - De'an Li
- School of Environment, Tsinghua University, Beijing, 10084, China
| | - Meng Yang
- School of Environment, Tsinghua University, Beijing, 10084, China
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11
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Su Y, Zhu Q, Li J, Wang D, Xing Z, Fang L. Fe(ii) and Mn(ii) removal by Ca(ii)–manganite (γ-MnOOH)-modified red mud granules in water. RSC Adv 2019; 9:10305-10313. [PMID: 35520885 PMCID: PMC9062367 DOI: 10.1039/c9ra00123a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 03/18/2019] [Indexed: 12/15/2022] Open
Abstract
In this study, a material (DLRMG) was synthesized by modifying Ca2+ and manganite (γ-MnOOH) on red mud granules (RMG), which were the main raw materials derived from industrial alumina. Moreover, a series of experiments were conducted on the adsorption of Fe2+ and Mn2+ in underground water. The prepared samples were analyzed by X-ray diffraction (XRD), thermogravimetric analysis-differential thermal analysis (TG-DTA), zeta potential analysis, BET and scanning electron microscopy (SEM); the concentration of the effluent was found to be of acceptable standard after the treatment. DLRMG continued to treat fluoride wastewater even after the saturated adsorption of Fe2+ and Mn2+, and the results clearly showed that the treatment was effective. Overall, the problems of red mud stockpile and pollution in China would be effectively controlled by DLRMG. The use of the waste of aluminum industry to prepare effective polluted materials for the treatment of underground water.![]()
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Affiliation(s)
- Yingying Su
- School of Chemistry and Materials Science
- Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion
- Heilongjiang University
- China
| | - Qi Zhu
- School of Chemistry and Materials Science
- Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion
- Heilongjiang University
- China
| | - Jian Li
- School of Chemistry and Materials Science
- Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion
- Heilongjiang University
- China
| | - Dongdong Wang
- School of Chemistry and Materials Science
- Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion
- Heilongjiang University
- China
| | - Zipeng Xing
- School of Chemistry and Materials Science
- Key Laboratory of Chemical Engineering Process & Technology for High-efficiency Conversion
- Heilongjiang University
- China
| | - Lei Fang
- School of Food Engineering
- Harbin University
- Harbin 150080
- China
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12
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Celeiro M, Dagnac T, Llompart M. Determination of priority and other hazardous substances in football fields of synthetic turf by gas chromatography-mass spectrometry: A health and environmental concern. CHEMOSPHERE 2018; 195:201-211. [PMID: 29268178 DOI: 10.1016/j.chemosphere.2017.12.063] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 12/07/2017] [Accepted: 12/10/2017] [Indexed: 06/07/2023]
Abstract
Due to the high concern generated in the last years about the safety of recycled tire rubber used for recreational sports surfaces, this study aims at evaluating the presence of forty organic compounds including polycyclic aromatic hydrocarbons (PAHs), phthalates, adipates, vulcanisation additives and antioxidants in recycled tire crumb of synthetic turf football fields. Ultrasound Assisted Extraction (UAE) was successfully employed to extract the target compounds from the crumb rubber, and analysis was performed by gas chromatography-mass spectrometry (GC-MS). The transfer of the target chemicals from the crumb rubber to the runoff water and to the air above the rubber surface has also been evaluated employing solid-phase microextraction (SPME). Samples from fifteen football fields were analysed, and the results revealed the presence of 24 of the 40 target compounds, including 14 of the 16 EPA PAHs, with total concentrations up to 50 μg g-1. Heavy metals such as Cd, Cr and Pb were also found. A partial transfer of organic compounds to the air and runoff water was also demonstrated. The analysis of rain water collected directly from the football field, showed the presence of a high number of the target compounds at concentrations reaching above 100 μg L-1. The environmental risk arising from the burning of crumb rubber tires has been assessed, as well, analysing the crumb rubber, and the air and water in contact with this material, showing a substantial increase both of the number and concentration of the hazardous chemicals.
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Affiliation(s)
- Maria Celeiro
- Laboratory of Research and Development of Analytical Solutions (LIDSA), Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, E-15782, Campus Vida, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Thierry Dagnac
- Agronomic and Agrarian Research Centre (INGACAL-CIAM), Unit of Organic Contaminants, Apartado 10, 15080, A Coruña, Spain
| | - Maria Llompart
- Laboratory of Research and Development of Analytical Solutions (LIDSA), Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, E-15782, Campus Vida, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.
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13
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Canepari S, Castellano P, Astolfi ML, Materazzi S, Ferrante R, Fiorini D, Curini R. Release of particles, organic compounds, and metals from crumb rubber used in synthetic turf under chemical and physical stress. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:1448-1459. [PMID: 29090445 DOI: 10.1007/s11356-017-0377-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 10/02/2017] [Indexed: 05/12/2023]
Abstract
The chemical and morphological characteristics of materials released under chemical and physical stress by different rubber granulates used as infill materials in synthetic turf (recycled scrap tires, natural rubber, and a new-generation thermoplastic elastomer) were compared.The headspace solid-phase micro-extraction GC-MS analysis evidenced that at 70 °C natural rubber and thermoplastic elastomer release amounts of organic species much higher than recycled scrap tires. In particular, the desorption of mineral oils, with a prevalence of toxicologically relevant low-viscosity alkanes in the range C17-C22, and plasticizers (diisobutyl phthalate) was clearly evidenced. The new-generation thermoplastic elastomer material also releases butylated hydroxytoluene.In slightly acidic conditions, quite high amounts of bio-accessible Zn, Cu, and Co are released from recycled scrap tires, while natural rubber releases mainly Se and Tl. In contrast, the thermoplastic elastomer does not contain significant concentrations of leachable heavy metals.The formation of small particles, also in the inhalable fraction, was evidenced by electron microscopy after mechanical or thermal treatment of natural rubber.
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Affiliation(s)
- Silvia Canepari
- Chemistry Department, Sapienza University of Rome, P.le Aldo Moro, 5, 00185, Rome, Italy.
| | - Paola Castellano
- Local Office of Aosta, INAIL-Italian Workers' Compensation Authority, Corso Padre Lorenzo, 18, 11100, Aosta, Italy
| | - Maria Luisa Astolfi
- Chemistry Department, Sapienza University of Rome, P.le Aldo Moro, 5, 00185, Rome, Italy
| | - Stefano Materazzi
- Chemistry Department, Sapienza University of Rome, P.le Aldo Moro, 5, 00185, Rome, Italy
| | - Riccardo Ferrante
- Department of Occupational Hygiene, INAIL-Italian Workers' Compensation Authority, Research Area, via Fontana Candida 1, 00040 Monteporzio Catone, Rome, Italy
| | - Dennis Fiorini
- Chemistry Division, School of Science and Technology, University of Camerino, V. S. Agostino 1, 62032, Camerino, MC, Italy
| | - Roberta Curini
- Chemistry Department, Sapienza University of Rome, P.le Aldo Moro, 5, 00185, Rome, Italy
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14
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Li J, Kosugi T, Riya S, Hashimoto Y, Hou H, Terada A, Hosomi M. Potential for leaching of arsenic from excavated rock after different drying treatments. CHEMOSPHERE 2016; 154:276-282. [PMID: 27058919 DOI: 10.1016/j.chemosphere.2016.03.129] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 03/19/2016] [Accepted: 03/28/2016] [Indexed: 06/05/2023]
Abstract
Leaching of arsenic (As) from excavated rock subjected to different drying methods is compared using sequential leaching tests and rapid small-scale column tests combined with a sequential extraction procedure. Although the total As content in the rock was low (8.81 mg kg(-1)), its resulting concentration in the leachate when leached at a liquid-to-solid ratio of 10 L kg(-1) exceeded the environmental standard (10 μg L(-1)). As existed mainly in dissolved forms in the leachates. All of the drying procedures applied in this study increased the leaching of As, with freeze-drying leading to the largest increase. Water extraction of As using the two tests showed different leaching behaviors as a function of the liquid-to-solid ratio, and achieved average extractions of up to 35.7% and 25.8% total As, respectively. Dissolution of As from the mineral surfaces and subsequent re-adsorption controlled the short-term release of As; dissolution of Fe, Al, and dissolved organic carbon played important roles in long-term As leaching. Results of the sequential extraction procedure showed that use of 0.05 M (NH4)2SO4 underestimates the readily soluble As. Long-term water extraction removed almost all of the non-specifically sorbed As and most of the specifically sorbed As. The concept of pollution potential indices, which are easily determined by the sequential leaching test, is proposed in this study and is considered for possible use in assessing efficacy of treatment of excavated rocks.
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Affiliation(s)
- Jining Li
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan
| | - Tomoya Kosugi
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan
| | - Shohei Riya
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan
| | - Yohey Hashimoto
- Department of Bioapplications and Systems Engineering (BASE), Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan
| | - Hong Hou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Dayangfang 8, Beijing 100012, PR China
| | - Akihiko Terada
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan
| | - Masaaki Hosomi
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan.
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15
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Unice KM, Bare JL, Kreider ML, Panko JM. Experimental methodology for assessing the environmental fate of organic chemicals in polymer matrices using column leaching studies and OECD 308 water/sediment systems: Application to tire and road wear particles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 533:476-87. [PMID: 26184905 DOI: 10.1016/j.scitotenv.2015.06.053] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/12/2015] [Accepted: 06/15/2015] [Indexed: 06/04/2023]
Abstract
Automobile tires require functional rubber additives including curing agents and antioxidants, which are potentially environmentally available from tire and road wear particles (TRWP) deposited in soil and sediment. A novel methodology was employed to evaluate the environmental fate of three commonly-used tire chemicals (N-cyclohexylbenzothiazole-2-sulfenamide (CBS), N-(1,3-dimethylbutyl)-N'-phenyl-1,4-phenylenediamine (6-PPD) and 1,3-diphenylguanidine (DPG)), using a road simulator, an artificial weathering chamber, column leaching tests, and OECD 308 sediment/water incubator studies. Environmental release factors were quantified for curing (f(C)), tire wear (f(W)), terrestrial weathering (f(S)), leaching from TRWP (f(L)), and environmental availability from TRWP (f(A)) by liquid chromatography-tandem mass spectroscopy (LC/MS/MS) analyses. Cumulative fractions representing total environmental availability (F(T)) and release to water (FR) were calculated for the tire chemicals and 13 transformation products. F(T) for CBS, DPG and 6-PPD inclusive of transformation products for an accelerated terrestrial aging time in soil of 0.1 years was 0.08, 0.1, and 0.06, respectively (equivalent to 6 to 10% of formulated mass). In contrast, a wider range of 5.5×10(-4) (6-PPD) to 0.06 (CBS) was observed for F(R) at an accelerated age of 0.1 years, reflecting the importance of hydrophobicity and solubility for determining the release to the water phase. Significant differences (p<0.05) in the weathering factor, f(S), were observed when chemicals were categorized by boiling point or hydrolysis rate constant. A significant difference in the leaching factor, f(L), and environmental availability factor, f(A), was also observed when chemicals were categorized by log K(ow). Our methodology should be useful for lifecycle analysis of other functional polymer chemicals.
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Affiliation(s)
| | | | | | - Julie M Panko
- Cardno ChemRisk, Pittsburgh, Pennsylvania, United States
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16
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Orndorff ZW, Daniels WL, Zipper CE, Eick M, Beck M. A column evaluation of Appalachian coal mine spoils' temporal leaching behavior. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 204:39-47. [PMID: 25912885 DOI: 10.1016/j.envpol.2015.03.049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 03/24/2015] [Accepted: 03/31/2015] [Indexed: 06/04/2023]
Abstract
Appalachian surface coal mine overburden affects water quality as drainage percolates through spoil disposal fills. This study evaluated leaching potentials of 15 spoils from south-central Appalachia. Most bulk samples were non acid-forming, all were low in total-S, (≤0.34%), and initial saturated paste specific conductance (SC) ranged from 264 to 3560 μS cm(-1). Samples were leached unsaturated (40 cycles) and leachates analyzed for pH, SC, and ion composition. Overall, leachates from unweathered spoils were higher in pH and SC than leachates from weathered spoils. Fine-textured spoils generally produced higher SCs than more coarsely textured spoils. Mean SC for all spoils decreased rapidly from an initial peak of 1468 μS cm(-1) (±150) to 247 μS cm(-1) (±23). Release patterns for most major ions reflected declining SC. Bicarbonate typically increased with successive leaches, replacing sulfate as the dominant anion. Column SC values were comparable to relevant published field data.
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Affiliation(s)
- Zenah W Orndorff
- Virginia Tech. Department of Crop and Soil Environmental Sciences, 330 Smyth Hall, Blacksburg, VA 24061, United States.
| | - W Lee Daniels
- Virginia Tech. Department of Crop and Soil Environmental Sciences, 330 Smyth Hall, Blacksburg, VA 24061, United States.
| | - Carl E Zipper
- Virginia Tech. Department of Crop and Soil Environmental Sciences, 330 Smyth Hall, Blacksburg, VA 24061, United States.
| | - Matt Eick
- Virginia Tech. Department of Crop and Soil Environmental Sciences, 330 Smyth Hall, Blacksburg, VA 24061, United States.
| | - Mike Beck
- Virginia Tech. Department of Crop and Soil Environmental Sciences, 330 Smyth Hall, Blacksburg, VA 24061, United States.
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17
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Allegrini E, Butera S, Kosson DS, Van Zomeren A, Van der Sloot HA, Astrup TF. Life cycle assessment and residue leaching: the importance of parameter, scenario and leaching data selection. WASTE MANAGEMENT (NEW YORK, N.Y.) 2015; 38:474-485. [PMID: 25573739 DOI: 10.1016/j.wasman.2014.12.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 11/17/2014] [Accepted: 12/16/2014] [Indexed: 06/04/2023]
Abstract
Residues from industrial processes and waste management systems (WMSs) have been increasingly reutilised, leading to landfilling rate reductions and the optimisation of mineral resource utilisation in society. Life cycle assessment (LCA) is a holistic methodology allowing for the analysis of systems and products and can be applied to waste management systems to identify environmental benefits and critical aspects thereof. From an LCA perspective, residue utilisation provides benefits such as avoiding the production and depletion of primary materials, but it can lead to environmental burdens, due to the potential leaching of toxic substances. In waste LCA studies where residue utilisation is included, leaching has generally been neglected. In this study, municipal solid waste incineration bottom ash (MSWI BA) was used as a case study into three LCA scenarios having different system boundaries. The importance of data quality and parameter selection in the overall LCA results was evaluated, and an innovative method to assess metal transport into the environment was applied, in order to determine emissions to the soil and water compartments for use in an LCA. It was found that toxic impacts as a result of leaching were dominant in systems including only MSWI BA utilisation, while leaching appeared negligible in larger scenarios including the entire waste system. However, leaching could not be disregarded a priori, due to large uncertainties characterising other activities in the scenario (e.g. electricity production). Based on the analysis of relevant parameters relative to leaching, and on general results of the study, recommendations are provided regarding the use of leaching data in LCA studies.
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Affiliation(s)
- E Allegrini
- Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby, Denmark.
| | - S Butera
- Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby, Denmark
| | - D S Kosson
- Vanderbilt University, Department of Civil and Environmental Engineering, Box 1831 Station B, Nashville, TN 37235, USA
| | - A Van Zomeren
- Energy Research Centre of the Netherlands (ECN), Department of Environmental Risk Assessment, P.O. Box 1, 1755 ZG Petten, The Netherlands
| | - H A Van der Sloot
- Hans van der Sloot Consultancy, Dorpsstraat 216, 1721 BV Langedijk, Netherlands
| | - T F Astrup
- Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby, Denmark
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18
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Grathwohl P. On equilibration of pore water in column leaching tests. WASTE MANAGEMENT (NEW YORK, N.Y.) 2014; 34:908-918. [PMID: 24636008 DOI: 10.1016/j.wasman.2014.02.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 01/17/2014] [Accepted: 02/16/2014] [Indexed: 06/03/2023]
Abstract
Column leaching tests are closer to natural conditions than batch shaking tests and in the last years have become more popular for assessing the release potential of pollutants from a variety of solids such as contaminated soils, waste, recycling and construction materials. Uncertainties still exist regarding equilibration of the percolating water with the solids, that might potentially lead to underestimation of contaminant concentrations in the effluent. The intention of this paper is to show that equilibration of pore water in a finite bath is fundamentally different from release of a certain fraction of the pollutant from a sample and that equilibrium is reached much faster at low liquid-to-solid ratios typical for column experiments (<0.25) than in batch tests with much higher liquid-to-solid ratios (e.g., 2-10). Two mass transfer mechanisms are elucidated: First-order type release (film diffusion) and intraparticle diffusion. For the latter, mass transfer slows down with time and sooner or later non-equilibrium conditions are observed at the column outlet after percolation has been started. Time scales of equilibrium leaching can be estimated based on a comparison of column length with the length of the mass transfer zone, which is equivalent to a Damköhler number approach. Mass transfer and diffusion coefficients used in this study apply to mass transfer mechanisms limited by diffusion in water, which is typical for release of organic compounds but also for dissolution of soluble minerals such as calcite, gypsum or similar. As a conclusion based on these theoretical considerations column tests (a) equilibrate much faster than batch leaching tests and (b) the equilibrium concentrations are maintained in the column effluent even for slow intraparticle diffusion limited desorption for extended periods of time (>days). Since for equilibration the specific surface area is crucial, the harmonic mean of the grain size is relevant (small grain sizes result in high concentrations even after short pre-equilibration of a column). The absolute time scales calculated with linear sorption and aqueous diffusion aim at organic compounds and are not valid for sparingly soluble mineral phases (e.g. metal oxides and silicates). However, the general findings on how different liquid-to-solid ratios and specific surface area influence equilibration time scales also apply to other mass transfer mechanisms.
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Affiliation(s)
- Peter Grathwohl
- University of Tübingen, Center of Applied Geosciences, Hölderlinstr. 12, 72074 Tübingen, Germany.
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19
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Cheng H, Hu Y, Reinhard M. Environmental and health impacts of artificial turf: a review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:2114-29. [PMID: 24467230 DOI: 10.1021/es4044193] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
With significant water savings and low maintenance requirements, artificial turf is increasingly promoted as a replacement for natural grass on athletic fields and lawns. However, there remains the question of whether it is an environmentally friendly alternative to natural grass. The major concerns stem from the infill material that is typically derived from scrap tires. Tire rubber crumb contains a range of organic contaminants and heavy metals that can volatilize into the air and/or leach into the percolating rainwater, thereby posing a potential risk to the environment and human health. A limited number of studies have shown that the concentrations of volatile and semivolatile organic compounds in the air above artificial turf fields were typically not higher than the local background, while the concentrations of heavy metals and organic contaminants in the field drainages were generally below the respective regulatory limits. Health risk assessment studies suggested that users of artificial turf fields, even professional athletes, were not exposed to elevated risks. Preliminary life cycle assessment suggested that the environmental impacts of artificial turf fields were lower than equivalent grass fields. Areas that need further research to better understand and mitigate the potential negative environmental impacts of artificial turf are identified.
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Affiliation(s)
- Hefa Cheng
- State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry, Chinese Academy of Sciences Guangzhou 510640, China
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