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Imran. Lead stabilization and remediation strategy with soil amendment in situ immobilization in contaminated range lands. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2024:1-10. [PMID: 38944679 DOI: 10.1080/15226514.2024.2372850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/01/2024]
Abstract
In situ immobilization is a potential approach that can be used to remediate low-to-medium levels of heavy-metal in contaminated-soil. There is little known about how modifications to soil characteristics may affect Pb's release from soil. The four different amendments, triple-superphosphate and attapulgite were combined in Ad-1; zeolite and triple-superphosphate were in Ad-2; hydroxyapatite and humus were in Ad-3; and nano-carbon. These amendments are mostly made of phyllosilicate minerals, humus, base minerals, and nano-carbon, respectively. Results revealed that the test amendments' maximal Pb-adsorption capacity varied from 7.47 to 17.67 mg g-1. Surface precipitation and ion-exchange were found to be the main mechanisms for Pb-adsorption by Ad-1 and Ad-2, while Ad-3 and Ad-4 were promising among the all, according to analysis of the modifications both before and after Pb loading. When the pH dropped (7-1) or the ion-strength rose (0-0.2 M), there was a discernible rise in the Pb-desorption percentages from the amendments. It was determined that Ad-3 and Ad-4 were more effective in situ immobilizing lead in contaminated-soils because of their high adsorption capacities (12.82 and 17.67 mg g-1) and low-desorption percentages (4.46-6.23%) at ion-strengths of 0.01-0.1 mol L-1 and pH levels ranging from 5 to 7.
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Affiliation(s)
- Imran
- College of Engineering, South China Agriculture University, Guangzhou, China
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2
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Pan P, Liu H, Liu A, Zhang X, Chen Q, Wang G, Liu B, Li Q, Lei M. Rhizosphere environmental factors regulated the cadmium adsorption by vermicompost: Influence of pH and low-molecular-weight organic acids. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 266:115593. [PMID: 37856985 DOI: 10.1016/j.ecoenv.2023.115593] [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: 06/26/2023] [Revised: 09/22/2023] [Accepted: 10/11/2023] [Indexed: 10/21/2023]
Abstract
Vermicompost is a promising amendment for immobilization of cadmium (Cd) in soils; however, its effectiveness can be influenced by rhizosphere environment conditions, such as pH and the presence of low-molecular-weight organic acids (LMWOAs). In this study, a batch experiment was conducted to examine the characteristics of Cd adsorption by vermicompost at different pH (pH = 3, 5, and 7) and after the addition of different LMWOAs (oxalic acid; citric acid; malic acid). Furthermore, a series of morphology and structural analyses were conducted to elucidate the mechanisms of observed effects. The results showed that the adsorption capacity of vermicompost for Cd increased as pH increased, and chemisorption dominated the adsorption process. Changes in pH altered adsorption performance by affecting the -OH groups of alcohol/phenol and the -CH2 groups of aliphatics. Further, the addition of oxalic acid promoted Cd adsorption, and the effect was concentration dependent. Modifying the verimicompost surface with more adsorption sites might be the main reason. Conversely, citric acid and malic acid showed the ability to inhibit Cd adsorption by vermicompost. Citric acid caused a blocking effect by covering flocculent substances on the vermicompost surface while reducing surface adsorption sites by dissolving mineral components such as iron oxides. However, the action of malic acid did not appear to be related to changes in morphology or the structure of vermicompost. Overall, the results of this study partially explain the limited effectiveness of Cd immobilization within the rhizosphere by vermicompost, and provide theoretical support for regulating rhizosphere environments to improve the effectiveness of vermicompost immobilization of Cd.
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Affiliation(s)
- Pan Pan
- Institute of Environmental and Plant Protection, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China; National Agricultural Environmental Science Observation and Experiment Station, Danzhou 571737, China; Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Haikou 571101, China
| | - Huizhan Liu
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Ang Liu
- Institute of Environmental and Plant Protection, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China
| | - Xinchun Zhang
- Institute of Environmental and Plant Protection, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China
| | - Qingmian Chen
- Institute of Environmental and Plant Protection, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China
| | - Guihua Wang
- College of Forestry, Hainan University, Haikou, Hainan 570228, China.
| | - Beibei Liu
- Institute of Environmental and Plant Protection, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China; National Agricultural Environmental Science Observation and Experiment Station, Danzhou 571737, China; Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Haikou 571101, China.
| | - Qinfen Li
- Institute of Environmental and Plant Protection, Chinese Academy of Tropical Agricultural Science, Haikou, Hainan 571101, China; National Agricultural Environmental Science Observation and Experiment Station, Danzhou 571737, China; Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Haikou 571101, China
| | - Mei Lei
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
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Luo Y, Xing R, Wu Y. Effect of simulated root exudates on the distribution, bioavailability, and fractionation of potentially toxic elements (PTEs) in various particle size fractions of zinc smelting slag: Implication of direct revegetation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118642. [PMID: 37480634 DOI: 10.1016/j.jenvman.2023.118642] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 07/09/2023] [Accepted: 07/15/2023] [Indexed: 07/24/2023]
Abstract
Direct revegetation is a promising strategy for phytostabilization of metal smelting slag sites. Slag comes into direct contact with root exudates when slag sites undergo direct revegetation. The slag particle size fractions are considered the key factor influencing the geochemical behaviour of potentially toxic elements (PTEs). However, the effects of root exudates on the geochemical behaviours of PTEs in various slag particle size fractions remain unclear. Here, the effects of simulated root exudates of perennial ryegrass (Lolium perenne) directly revegetated at a zinc smelting slag site on the distribution, bioavailability, and fractionation of PTEs (Cu, Pb, Zn, and Cd) in various slag particle size fractions were investigated. The results showed that PTEs mainly occurred in the <1 mm slag particles; the mass loads of PTEs in the <1 mm slag particles were higher than those in the >1 mm slag particles. The bioavailability of Cu, Zn, and Cd rather than Pb in the slag increased as the particle size decreased. There was a decrease in the <0.25 and 1-2 mm slag particles and an increase in the 0.25-0.5, 0.5-1, and >2 mm slag particles in the presence of root exudates. Root exudates enhanced the transformation of acid-soluble PTEs into other more stable fractions in various slag particle size fractions. Root exudates enhanced the aggregation of slag particles associated with the migration of PTEs, causing differences in the geochemical behaviour of PTEs in various slag particle size fractions. These findings are beneficial for understanding the geochemical behaviour of PTEs in metal smelting slags undergoing direct revegetation and provide an important basis for the guidance of environmental risk management of the revegetated metal smelting slag sites.
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Affiliation(s)
- Youfa Luo
- Key Laboratory of Kast Georesources and Environment, Ministry of Education, Guizhou University, Guiyang, 550025, China; Guizhou Karst Environmental Ecosystems Observation and Research Station, Ministry of Education, Guiyang, 550025, China; Guizhou Hostile Environment Ecological Restoration Technology Engineering Research Centre, Guizhou University, Guiyang, 550025, China.
| | - Rongrong Xing
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Yonggui Wu
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China; Guizhou Karst Environmental Ecosystems Observation and Research Station, Ministry of Education, Guiyang, 550025, China; Guizhou Hostile Environment Ecological Restoration Technology Engineering Research Centre, Guizhou University, Guiyang, 550025, China.
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4
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Jalali M, Jalali M, Antoniadis V. The release of Cd, Cu, Fe, Mn, Ni, Pb, and Zn from clay loam and sandy loam soils under the influence of various organic amendments and low-molecular-weight organic acids. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:132111. [PMID: 37499502 DOI: 10.1016/j.jhazmat.2023.132111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/28/2023] [Accepted: 07/19/2023] [Indexed: 07/29/2023]
Abstract
Low-molecular-weight organic acids (LMWOAs) interact with potentially toxic elements (PTEs) and affect their mobility; however, the effect of different amendments on PTEs release from soils when added along with LMWOAs is still unclear. In this study, two soils (a clay loam and a sandy loam) amended with sugar beet bagasse ash (SBBA), poultry manure (PM), sewage sludge (SS) from Kermanshah city (SSK), and SS from Toyserkan city (SST) at a rate of 5 %. In these treatments we studied release of Cd, Cu, Fe, Mn, Ni, Pb, and Zn with citric, oxalic, and malic acids added at 10 different rates each, i.e., 0.1, 1, 2.5, 5, 10, 30, 40, 50, 70, and 100 mmol L-1. We found that the percentage of PTEs release was higher for citric, followed by oxalic and malic acids. The highest amount of PTEs released in both soils decreased in the following order: SST > SBBA > SSK > PM. The percentage of PTEs complexed with LMWOAs and the log activity of PTEs species mostly increased with decreasing pH. It could be concluded that the application of PM is more environmentally friendly than that of the other amendments. Since Cd had the highest percentage of release in all treated soils and LMWOAs, more consideration should be given to Cd to prevent environmental pollution.
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Affiliation(s)
- Mohsen Jalali
- Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamedan, Iran.
| | - Mahdi Jalali
- Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamedan, Iran
| | - Vasileios Antoniadis
- University of Thessaly, Department of Agriculture Crop Production and Rural Environment, Volos, Greece
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Li Y, Rahman SU, Qiu Z, Shahzad SM, Nawaz MF, Huang J, Naveed S, Li L, Wang X, Cheng H. Toxic effects of cadmium on the physiological and biochemical attributes of plants, and phytoremediation strategies: A review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 325:121433. [PMID: 36907241 DOI: 10.1016/j.envpol.2023.121433] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 02/20/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
Anthropogenic activities pose a more significant threat to the environment than natural phenomena by contaminating the environment with heavy metals. Cadmium (Cd), a highly poisonous heavy metal, has a protracted biological half-life and threatens food safety. Plant roots absorb Cd due to its high bioavailability through apoplastic and symplastic pathways and translocate it to shoots through the xylem with the help of transporters and then to the edible parts via the phloem. The uptake and accumulation of Cd in plants pose deleterious effects on plant physiological and biochemical processes, which alter the morphology of vegetative and reproductive parts. In vegetative parts, Cd stunts root and shoot growth, photosynthetic activities, stomatal conductance, and overall plant biomass. Plants' male reproductive parts are more prone to Cd toxicity than female reproductive parts, ultimately affecting their grain/fruit production and survival. To alleviate/avoid/tolerate Cd toxicity, plants activate several defense mechanisms, including enzymatic and non-enzymatic antioxidants, Cd-tolerant gene up-regulations, and phytohormonal secretion. Additionally, plants tolerate Cd through chelating and sequestering as part of the intracellular defensive mechanism with the help of phytochelatins and metallothionein proteins, which help mitigate the harmful effects of Cd. The knowledge on the impact of Cd on plant vegetative and reproductive parts and the plants' physiological and biochemical responses can help selection of the most effective Cd-mitigating/avoiding/tolerating strategy to manage Cd toxicity in plants.
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Affiliation(s)
- Yanliang Li
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong, 523808, China; Dongguan Key Laboratory of Water Pollution Control and Ecological Safety Regulation, Dongguan, Guangdong, 523808, China
| | - Shafeeq Ur Rahman
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong, 523808, China; MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Zhixin Qiu
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong, 523808, China; Dongguan Key Laboratory of Water Pollution Control and Ecological Safety Regulation, Dongguan, Guangdong, 523808, China
| | - Sher Muhammad Shahzad
- Department of Soil and Environmental Sciences, College of Agriculture, University of Sargodha, Sargodha, Punjab, Pakistan
| | | | - Jianzhi Huang
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong, 523808, China; Dongguan Key Laboratory of Water Pollution Control and Ecological Safety Regulation, Dongguan, Guangdong, 523808, China
| | - Sadiq Naveed
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Lei Li
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong, 523808, China; Dongguan Key Laboratory of Water Pollution Control and Ecological Safety Regulation, Dongguan, Guangdong, 523808, China
| | - Xiaojie Wang
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Hefa Cheng
- MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China.
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Faragó T, Špirová V, Blažeková P, Lalinská-Voleková B, Macek J, Jurkovič Ľ, Vítková M, Hiller E. Environmental and health impacts assessment of long-term naturally-weathered municipal solid waste incineration ashes deposited in soil-old burden in Bratislava city, Slovakia. Heliyon 2023; 9:e13605. [PMID: 36873465 PMCID: PMC9976324 DOI: 10.1016/j.heliyon.2023.e13605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/26/2023] [Accepted: 02/07/2023] [Indexed: 02/11/2023] Open
Abstract
Municipal solid waste incineration (MSWI) is an effective method for reducing the volume/mass of waste. However, MSWI ashes contain high concentrations of many substances, including trace metal (loid)s, that could be released into the environment and contaminate soils and groundwater. In this study, attention was focused on the site near the municipal solid waste incinerator where MSWI ashes are deposited on the surface without any control. Here, combined results (chemical and mineralogical analyses, leaching tests, speciation modelling, groundwater chemistry and human health risk assessment) are presented to assess the impact of MSWI ash on the surrounding environment. The mineralogy of ∼forty years old MSWI ash was diverse, and quartz, calcite, mullite, apatite, hematite, goethite, amorphous glasses and several Cu-bearing minerals (e.g. malachite, brochantite) were commonly detected. In general, the total concentrations of metal (loid)s in MSWI ashes were high, following the order: Zn (6731 mg/kg) > Ba (1969 mg/kg) ≈ Mn (1824 mg/kg) > Cu (1697 mg/kg) > Pb (1453 mg/kg) > Cr (247 mg/kg) > Ni (132 mg/kg) > Sb (59.4 mg/kg) > As (22.9 mg/kg) ≈ Cd (20.6 mg/kg). Cadmium, Cr, Cu, Pb, Sb and Zn exceeded the indication or even intervention criteria for industrial soils defined by the Slovak legislation. Batch leaching experiments with diluted citric and oxalic acids that simulate the leaching of chemical elements under rhizosphere conditions documented low dissolved fractions of metals (0.00-2.48%) in MSWI ash samples, showing their high geochemical stability. Non-carcinogenic and carcinogenic risks were below the threshold values of 1.0 and 1 × 10-6, respectively, with soil ingestion being the most important exposure route for workers. The groundwater chemistry was unaffected by deposited MSWI ashes. This study may be useful in determining the environmental risks of trace metal (loid)s in weathered MSWI ashes that are loosely deposited on the soil surface.
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Affiliation(s)
- Tomáš Faragó
- Department of Geochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovak Republic
| | - Veronika Špirová
- Department of Geochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovak Republic
| | - Petra Blažeková
- Department of Geochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovak Republic
| | | | - Juraj Macek
- Department of Geochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovak Republic.,The Center of Environmental Services, Ltd., Kutlíkova 17, 852 50 Bratislava, Slovak Republic
| | - Ľubomír Jurkovič
- Department of Geochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovak Republic
| | - Martina Vítková
- Department of Environmental Geosciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 00, Prague - Suchdol, Czech Republic
| | - Edgar Hiller
- Department of Geochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovak Republic
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Zhang H, Zhang R, Lu T, Qi W, Zhu Y, Lu M, Qi Z, Chen W. Enhanced transport of heavy metal ions by low-molecular-weight organic acids in saturated porous media: Link complex stability constants to heavy metal mobility. CHEMOSPHERE 2022; 290:133339. [PMID: 34929284 DOI: 10.1016/j.chemosphere.2021.133339] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/19/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
Environment-ubiquitous low-molecular-weight organic acids (LMWOAs) can interact with heavy metal ions and thus affect their mobility in subsurface aquifers. Herein, the effects of LMWOAs (including acetic acid, tartaric acid, malonic acid, oxalic acid, and citric acid) on the mobility of heavy metal ions (including Cd2+, Zn2+, Ni2+, Mn2+, and Co2+) in porous media were investigated to reveal the role of the stability constants of metal-LMWOA complexes in the mobility of heavy metal ions in porous media. The results showed that the mobility of different metal ions followed the order of Cd2+ < Zn2+ < Ni2+ < Mn2+ < Co2+ despite of LMWOAs-free or LMWOAs-addition. For each heavy metal, all the organic acids enhanced its transport by forming stable non-adsorbing metal-LMWOA complexes and the enhanced ability followed the order of citric acid > oxalic acid > malonic acid > tartaric acid > acetic acid. An interesting finding was that there was a significantly positive correlation between the enhanced abilities of LMWOAs to metal mobility and the complex stability constants (log K) (R2 = 0.801-0.961, p < 0.05), indicating that the complex stability of metal-LMWOA was the dominant factor responsible for the enhanced transport of heavy metal ions. Meanwhile, the linear slope indicated the intensity of enhancement of LMWOAs on heavy metal mobility was heavy metal type-dependent. This study proposed that the complex stability of metal-LMWOA could be an indicator to quantify and predict the impact of LMWOAs on the mobility of heavy metals.
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Affiliation(s)
- Haojing Zhang
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, Henan International Joint Laboratory of Medicinal Plants Utilization, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Ruoyu Zhang
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, Henan International Joint Laboratory of Medicinal Plants Utilization, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China; Ministry of Education Key Laboratory of Humid Subtropical Eco-geographical Process, Fujian Provincial Key Laboratory for Plant Eco-physiology, College of Geographical Science, Fujian Normal University, Fuzhou, Fujian, 350007, China
| | - Taotao Lu
- Department of Hydrology, University of Bayreuth, Bayreuth D, 95440, Germany
| | - Wei Qi
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, Henan International Joint Laboratory of Medicinal Plants Utilization, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Yuwei Zhu
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, Henan International Joint Laboratory of Medicinal Plants Utilization, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Minghua Lu
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, Henan International Joint Laboratory of Medicinal Plants Utilization, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Zhichong Qi
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, Henan International Joint Laboratory of Medicinal Plants Utilization, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China.
| | - Weifeng Chen
- Ministry of Education Key Laboratory of Humid Subtropical Eco-geographical Process, Fujian Provincial Key Laboratory for Plant Eco-physiology, College of Geographical Science, Fujian Normal University, Fuzhou, Fujian, 350007, China.
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8
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Yao J, Wang H, Ma C, Cao Y, Chen W, Gu L, He Q, Liu C, Xiong J, Ma J, Huangfu X, Liu H. Cotransport of thallium(I) with polystyrene plastic particles in water-saturated porous media. JOURNAL OF HAZARDOUS MATERIALS 2022; 422:126910. [PMID: 34416700 DOI: 10.1016/j.jhazmat.2021.126910] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/31/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
Exploring the transport behaviors of thallium (Tl) in porous media is crucial for predicting Tl pollution in natural soils and groundwater. In recent years, the misuse of plastics has led to plastic becoming an emerging pollutant in soil. In this work, the effects of plastic particles on Tl(I) transport in water-saturated sand columns were investigated under different ionic strengths (ISs), pH values, and plastic particle sizes. The two-site nonequilibrium model was selected to fit the breakthrough curves (BTCs) of Tl(I). The results demonstrated that nanoplastics (NPs) accelerated Tl(I) transport at pH 7, which might be attributed to the competitive adsorption of NPs and Tl(I) on sand surfaces. However, at pH 5, the deposited NPs might provide more adsorption sites for Tl(I), and thus enhance its retention in the columns. In addition, the "straining" process could intercept microplastics (MPs) with Tl(I) that was attached under unfavorable attachment conditions, which would result in the inhibited mobility of Tl(I). On the other hand, the migration of plastics was restrained to some extent when Tl(I) was present. Overall, the findings from this work provided a new perspective for understanding the transport of Tl(I) and plastics in subsurface environments.
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Affiliation(s)
- Jinni Yao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Hainan Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Chengxue Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Yu Cao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Wanpeng Chen
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Li Gu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Caihong Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Jiaming Xiong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Xiaoliu Huangfu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China.
| | - Hongxia Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China.
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Zulkafflee NS, Mohd Redzuan NA, Nematbakhsh S, Selamat J, Ismail MR, Praveena SM, Yee Lee S, Abdull Razis AF. Heavy Metal Contamination in Oryza sativa L. at the Eastern Region of Malaysia and Its Risk Assessment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:739. [PMID: 35055560 PMCID: PMC8775590 DOI: 10.3390/ijerph19020739] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/21/2021] [Accepted: 09/28/2021] [Indexed: 02/06/2023]
Abstract
Paddy plants tend to accumulate heavy metals from both natural and anthropogenic sources, and this poses adverse risks to human health. The objective of this study was to investigate heavy metal contamination in paddy plants in Kelantan, Malaysia, and its health risk assessment. The bioaccumulation of heavy metals was studied by means of enrichment (EF) and translocation factors (TF). The health risk assessment was performed based on USEPA guidelines. The EF for heavy metals in the studied areas was in the descending order of Cu > As > Cr > Cd > Pb. Meanwhile, Cr and Pb exhibited higher TF values from stem to grain compared with the others. The combined hazard index (HI) resulting from five heavy metals exceeded the acceptable limit (HI >1). The lifetime cancer risk, in both adult and children, was beyond the acceptable limit (10-4) and mainly resulted from exposure. The total cancer risk (CRt) due to simultaneous exposures to multiple carcinogenic elements also exceeded 10-4. In conclusion, intake of heavy metal through rice ingestion is likely to cause both non-carcinogenic and carcinogenic health risks. Further research is required to investigate the extent of heavy metal contamination in agricultural soils and, moreover, to establish human exposure as a result of rice consumption.
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Affiliation(s)
- Nur Syahirah Zulkafflee
- Department of Food Science, Faculty of Food Science and Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia; (N.S.Z.); (N.A.M.R.); (J.S.)
| | - Nurul Adillah Mohd Redzuan
- Department of Food Science, Faculty of Food Science and Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia; (N.S.Z.); (N.A.M.R.); (J.S.)
| | - Sara Nematbakhsh
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Serdang 43400, Malaysia; (S.N.); (S.M.P.)
| | - Jinap Selamat
- Department of Food Science, Faculty of Food Science and Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia; (N.S.Z.); (N.A.M.R.); (J.S.)
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Serdang 43400, Malaysia; (S.N.); (S.M.P.)
| | - Mohd Razi Ismail
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Sarva Mangala Praveena
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Serdang 43400, Malaysia; (S.N.); (S.M.P.)
- Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Malaysia
| | - Soo Yee Lee
- Natural Medicines and Products Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Ahmad Faizal Abdull Razis
- Department of Food Science, Faculty of Food Science and Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia; (N.S.Z.); (N.A.M.R.); (J.S.)
- Laboratory of Food Safety and Food Integrity, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Serdang 43400, Malaysia; (S.N.); (S.M.P.)
- Natural Medicines and Products Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, Serdang 43400, Malaysia;
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10
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Low Molecular Weight Organic Acids Increase Cd Accumulation in Sunflowers through Increasing Cd Bioavailability and Reducing Cd Toxicity to Plants. MINERALS 2021. [DOI: 10.3390/min11030243] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The use of low molecular weight organic acids (LMWOAs) for the phytoremediation of heavy metals has become a promising technique. We chose five kinds of organic acids (oxalic acid (OA), acetic acid (AA), tartaric acid (TA), malic acid (MA), and citric acid (CA)) with six application rates (1, 2, 3, 4, 5, and 6 mmol/kg) and planted sunflowers (Helianthus annuus L.) in Cd-polluted soil to study the efficiency of the phytoremediation of Cd and the degree of Cd toxicity to plants. Treatment with no acid application served as the control (CK). We analyzed the plant height dry matter and the Cd and nonprotein sulfhydryl (NPT) contents in the soil and plant tissues. OA, AA, TA, MA, and CA increased plant heights by 17.6–47.40%, 21.25–39.17%, 12.5–35.52, 5.10–30.50%, and 16.15–49.17%, respectively; shoot biomass of the sunflowers was increased except with MA. NPT decreased under LMWOA application, which, in the roots, increased with the increase in root Cd under LMWOA treatment; however, there was no obvious relationship in the stems and leaves. The composition of Cd in the soil changed significantly under the LMWOA treatments compared to the CK, and the changes in carbonate Cd and Fe-Mn oxide Cd were the most prominent. The plant Cd accumulation of OA, AA, TA, MA, and CA increased by 43.31%, 55.25%, 48.69%, 0.52%, and 32.94%, respectively, and the increase in root Cd content and shoot dry matter quality promoted the increase in Cd accumulation. The LMWOAs were more likely to affect the phytoremediation of Cd by changing total P (TP) rather than total N (TN).
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11
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Xiao Z, Zou D, Zeng X, Zhang L, Liu F, Wang A, Zeng Q, Zhang G, Li L. Cadmium accumulation in oilseed rape is promoted by intercropping with faba bean and ryegrass. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 205:111162. [PMID: 32836158 DOI: 10.1016/j.ecoenv.2020.111162] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/02/2020] [Accepted: 08/09/2020] [Indexed: 05/27/2023]
Abstract
The mechanisms of intercropping increasing plant biomass, cadmium accumulation, and organic acids secreted in rhizosphere soil are still unclear. Oilseed rape and intercrops were grown in boxes separated either with no barrier between the compartments or by a nylon mesh barrier (37 μm) to license partial root interaction, or a solid barrier to stop any root interactions. Two intercropping systems (oilseed rape-faba bean and oilseed rape-ryegrass) were carried out in soil with Cd content of 5 mg/kg. The intermingling of roots between oilseed rape and faba bean enhanced the biomass of oilseed rape. However, the biomass was negatively affected implying the higher nutrient apportionment to the ryegrass than oilseed rape. Oilseed rape intercropping with both faba bean and ryegrass played a positive role in the shoot Cd concentration of oilseed rape. The intermingling of roots played a positive role in the citric and malic acids when intercropping with faba bean. A remarkable increase in water-soluble Cd and DTPA-Cd content was observed during oilseed rape-faba bean complete root interaction treatment, up to 175.00% and 46.65%, respectively, which compare with the monoculture treatment. In both systems, the translocation factor values were higher for oilseed rape (O-F system) than for the other test plants and were always >1. Thus the Cd removal potential of oilseed rape can be further improved in the future by optimizing agronomic practices and intercropping with faba bean.
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Affiliation(s)
- Zhihua Xiao
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Dongsheng Zou
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Xinyi Zeng
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Liqing Zhang
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Fen Liu
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Andong Wang
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Qingru Zeng
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China
| | - Guolin Zhang
- The College of Urban and Environmental Sciences, The Graduate School of Landscape Architecture, PKU, Beijing, 100871, PR China
| | - Longcheng Li
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan, 410128, PR China; Key Laboratory for Rural Ecosystem Health in the Dongting Lake Area of Hunan Province, Changsha, 410128, PR China.
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12
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Luo Y, Wu X, Sun H, Wu Y. Root-induced changes in aggregation characteristics and potentially toxic elements (PTEs) speciation in a revegetated artificial zinc smelting waste slag site. CHEMOSPHERE 2020; 243:125414. [PMID: 31783184 DOI: 10.1016/j.chemosphere.2019.125414] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 11/10/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
Root-induced changes play a crucial role in influencing the fate and speciation of potentially toxic elements (PTEs) in contaminated soils, but their role in the phytostabilization of waste slag sites remain unclear. The aim of this study was to determine the effect of four phytostabilization plants, Broussonetia papyrifera, Arundo donax, Robinia pseudoacacia, and Cryptomeria fortunei, planted in a zinc smelting waste slag site for 5 years on PTEs speciation and the mineral and aggregation characteristics at the interface of the waste slag-plant system. The results showed that the presence of a higher content of oxalic acid in the rhizosphere slags of the four plant species than in the bare slag. Revegetation of the waste slag with the four plant species significantly changed the mineral composition and morphology of the waste slag. The mass percentage of large particles (1-5 mm) and small particles (0.5-1 mm, 0.25-0.5 mm, and <0.25 mm) in the rhizosphere slags decreased and increased, respectively. The PTEs (Cu, Pb, Zn, and Cd) in most of the rhizosphere slags were mainly distributed within the small particles, and the enrichment coefficients of PTEs in the large particles and small particles were less than and greater than 1, respectively. The bioavailability of the PTEs in the waste slag increased with decreasing particle size. Root-induced the transformation of acid-soluble PTEs into their reducible, oxidizable, and residual forms in the different waste slag particles weathered in the rhizosphere. These results suggested that there are root-induced changes in the aggregation characteristics and geochemical behaviours of PTEs in waste slag fractions during the phytoremediation of waste slag sites.
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Affiliation(s)
- Youfa Luo
- Key Laboratory of Kast Georesources and Environment, Ministry of Education, Guizhou University, Guiyang, 550025, China; Key Laboratory of Karst Environment and Geohazard, Ministry of Land and Resources, Guizhou University, Guiyang, 550025, China; College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China; Guizhou Kast Environmental Ecosystem Observation and Research Station, Ministry of Education, Guiyang, 550025, China.
| | - Xingyu Wu
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Hang Sun
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Yonggui Wu
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, China; Guizhou Kast Environmental Ecosystem Observation and Research Station, Ministry of Education, Guiyang, 550025, China.
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13
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Tao Q, Zhao J, Li J, Liu Y, Luo J, Yuan S, Li B, Li Q, Xu Q, Yu X, Huang H, Li T, Wang C. Unique root exudate tartaric acid enhanced cadmium mobilization and uptake in Cd-hyperaccumulator Sedum alfredii. JOURNAL OF HAZARDOUS MATERIALS 2020; 383:121177. [PMID: 31648122 DOI: 10.1016/j.jhazmat.2019.121177] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 09/03/2019] [Accepted: 09/05/2019] [Indexed: 06/10/2023]
Abstract
Low molecular weight organic acids (LMWOA) involved in heavy metal tolerance, translocation, and accumulation in plants. However, underlying mechanism of LMWOA secretion in metal mobilization and uptake in hyperaccumulator still need to be identified. In this study, a 13C labeling rhizobox was designed to investigate the composition and distribution of LMWOA in the rhizosphere of S. alfredii. The result showed that about 2.30%, 2.25% and 2.35% of the assimilated 13C was incorporated into oxalic acid, malic acid, and tartaric acid in rhizosphere of S. alfredii after 13CO2 assimilation, respectively. Oxalic acid, malic acid, and tartaric acid were the predominant LMWOA in rhizosphere soil solution of hyperaccumulating ecotype (HE) S. alfredii, however, almost no tartaric acid was detected for non-hyperaccumulating ecotype (NHE). Tartaric acid was identified as the unique root exudate from HE S. alfredii which was mainly distributed within the range of rhizosphere 0-6 mm. Tartaric acid significantly increased the solubility of four Cd minerals. HE S. alfredii treated with tartrate + CdCO3 had higher Cd contents and larger biomass than CdCO3 treatment. Cadmium accumulation in HE S. alfredii was promoted by the exudation of tartaric acid, which was highly efficient in Cd solubilization due to the formation of soluble Cd-tartrate complexes.
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Affiliation(s)
- Qi Tao
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Junwen Zhao
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Jinxing Li
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China
| | - Yuankun Liu
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China
| | - Jipeng Luo
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China
| | - Shu Yuan
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Bing Li
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Qiquan Li
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Qiang Xu
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiaofang Yu
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611130, China
| | - Huagang Huang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - Tingqiang Li
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China.
| | - Changquan Wang
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China.
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14
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Kubier A, Hamer K, Pichler T. Cadmium Background Levels in Groundwater in an Area Dominated by Agriculture. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2020; 16:103-113. [PMID: 31368630 DOI: 10.1002/ieam.4198] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/20/2019] [Accepted: 07/30/2019] [Indexed: 06/10/2023]
Abstract
Cadmium is a highly toxic trace metal, which can be of geogenic or anthropogenic origin, for example, minerals, phosphate fertilizers, and combustion emissions. Due to its low sorption affinity compared to other heavy metals, Cd is easily mobilized, potentially resulting in elevated Cd concentrations in groundwater. This study assessed background levels of Cd in groundwater related to hydrogeology and hydrogeochemical processes through evaluation of a large hydrogeochemical data set composed of groundwater analyses from 6300 wells in Northwestern Germany. Calculated Cd background levels in groundwater were between 0.01 µg/L in hydrogeological units with mainly reducing conditions and 0.98 µg/L in less reducing groundwater recharge areas. The results showed that groundwater Cd concentrations above 0.5 µg/L (the German threshold value) are not necessarily elevated but could be the regional or ambient background level, depending on the hydrogeological unit. What would be considered as ambient background levels, however, indicated the influence by continuous intensive land use as well as the local geology, which is dominated by glacial deposits. Cadmium concentrations in groundwater were mainly controlled by hydrogeochemical and hydrogeological parameters and not by the amount of anthropogenic Cd input, in particular through the use of phosphate fertilizers. Instead, analyses of the solid phase revealed that Cd release from the aquifer matrix due to changes in hydrogeochemical parameters was more likely. Aquifer sediments in Northwestern Germany can be enriched in Cd originating from multiple sources, which in turn can cause elevated Cd concentrations in groundwater. Integr Environ Assess Manag 2019;00:1-11. © 2019 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Affiliation(s)
- Andreas Kubier
- Department of Geosciences, University of Bremen, Bremen, Germany
| | - Kay Hamer
- Department of Geosciences, University of Bremen, Bremen, Germany
| | - Thomas Pichler
- Department of Geosciences, University of Bremen, Bremen, Germany
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15
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Zhang H, Lu T, Shang Z, Li Y, He J, Liu S, Li D, Zhou Y, Qi Z. Transport of Cd 2+ through saturated porous media: Insight into the effects of low-molecular-weight organic acids. WATER RESEARCH 2020; 168:115182. [PMID: 31634706 DOI: 10.1016/j.watres.2019.115182] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 10/01/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Low-molecular-weight organic acids (LMWOAs) are ubiquitous in the aquatic environment and consequently may affect the heavy metal transport in aquifer systems. In this study, the influences of LMWOAs on the transport of Cd2+ under different pH conditions in saturated porous media were evaluated. For this, three LMWOAs such as acetic acid, tartaric acid, and citric acid were employed. A two-site nonequilibrium transport model was applied to simulate the transport data. Under acidic conditions (pH 5.0), the results indicated that LMWOAs inhibited the transport of Cd2+ even at the low concentrations of organic acids (i.e., 0.05 and 0.1 mM). The inhibition effects might be attributed to the complexation role of the sand surface-bound organic acids and also electrostatic interaction. Meanwhile, the inhibition effects of LMWOAs on Cd2+ transport in the following order of citric acid > tartaric acid > acetic acid, which was also in agreement with the decreasing complex stability constants between Cd2+ and LMWOAs. This order may be dependent on their molecular structures (i.e., amount and type of functional groups) and complexing strength. Interestingly, when the LMWOA concentrations 0.5 mM, tartaric acid and citric acid still inhibited Cd2+ transport, while acetic acid slightly enhanced the Cd2+ mobility due to its weaker complexing strength. However, under neutral conditions (pH 7.0), LMWOAs generally enhanced the transport of Cd2+. The transport-enhancement of LMWOAs was ascribed to the formation of stable aqueous non-adsorbing Cd-organic acid complexes. In addition, citric acid could obviously inhibit the transport of Cd2+ under competitive transport conditions (i.e., with competing cations), which is mainly due to different complex affinities of citric acid to Pb2+ and Cd2+. These findings demonstrate that LMWOAs may inhibit or facilitate Cd2+ transport under different environmental conditions. Thus, environmental assessment concerning the transport of heavy metals should consider the roles of organic acids.
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Affiliation(s)
- Haojing Zhang
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Taotao Lu
- Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin, 300350, China; Department of Hydrology, University of Bayreuth, Bayreuth, D-95440, Germany
| | - Zhongbo Shang
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Yanxiang Li
- The Testing Center of Shandong Bureau of China Metallurgical Geology Bureau, Jinan, 250014, China
| | - Jianying He
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Shanhu Liu
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Deliang Li
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Yanmei Zhou
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
| | - Zhichong Qi
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China; Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Nankai University, Tianjin, 300350, China.
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16
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Kubier A, Wilkin RT, Pichler T. Cadmium in soils and groundwater: A review. APPLIED GEOCHEMISTRY : JOURNAL OF THE INTERNATIONAL ASSOCIATION OF GEOCHEMISTRY AND COSMOCHEMISTRY 2019; 108:1-16. [PMID: 32280158 PMCID: PMC7147761 DOI: 10.1016/j.apgeochem.2019.104388] [Citation(s) in RCA: 344] [Impact Index Per Article: 68.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cadmium (Cd) is a non-essential trace element that is widely distributed in the environment. Both geogenic and anthropogenic sources can elevate Cd concentrations in soils and groundwater, which are important for maintaining healthy supplies of food and safe drinking water. Elevated Cd doses are carcinogenic to humans. The WHO Guidelines for Drinking-Water Quality recommend a guideline value for Cd of 3 μg/L. Important anthropogenic Cd sources include mining, atmospheric deposition of combustion emissions, and the use of Cd-containing fertilizers. We document several cases of Cd pollution in soil and groundwater based on worldwide accounts. Besides anthropogenic Cd sources, Cd is also incorporated into sulfides, carbonates, and phosphorites resulting in elevated Cd concentrations in associated rock types. The crustal median Cd content is 0.2 mg/kg. In soils, Cd occurs at concentrations of 0.01 to 1 mg/kg with a worldwide mean of 0.36 mg/kg. Weathering can lead to Cd concentrations up to 5 μg/L in soil water and up to 1 μg/L in groundwater. In aqueous solutions, Cd generally occurs as the divalent Cd2+ and it is mobilized mainly in oxic, acidic conditions. Cadmium sorption is enhanced by the presence of high amounts of hydrous oxides, clay minerals, and organic matter, and its mobility is further influenced by pH, the redox state, and ionic strength of the solution. However, Cd can remain in solution as water-soluble complexes with anions, such as CdCl+ and Cd(SO4)2 2-, and dissolved organic matter while sorption and precipitation decrease the aqueous concentration of most other heavy metals. As a consequence, Cd is one of the most mobile heavy metals in the environment. The elevated mobilization potential, e.g., through competition and ligand induced desorption, is the reason for faster Cd release from soil into groundwater than other heavy metals. The goal of this study was to present a broad overview of the origin and concentration of Cd in groundwater, and its reaction pathways in aquatic environments. To gain an overview of the hydrochemical behavior of Cd, cases of Cd pollution in soil and groundwater, studies investigating Cd release, and information about the legal framework were compiled.
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Affiliation(s)
- Andreas Kubier
- University of Bremen, Department of Geosciences, D-28359, Bremen, Germany
| | - Richard T. Wilkin
- U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, Ada, OK, 74820, USA
| | - Thomas Pichler
- University of Bremen, Department of Geosciences, D-28359, Bremen, Germany
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17
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Chen J, Lu T, Wang Y, Li J, Fu X, Qi Z, Zhang Q. Transport of graphene oxide nanoparticles in saturated kaolinite- and goethite-coated sand columns: effects of low-molecular-weight organic acids. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:24922-24932. [PMID: 31243660 DOI: 10.1007/s11356-019-05683-0] [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: 01/23/2019] [Accepted: 06/04/2019] [Indexed: 06/09/2023]
Abstract
The effects of low-molecular-weight organic acids (LMWOAs) on the transport of graphene oxide nanoparticles in saturated kaolinite- and goethite-coated sand columns were studied. Acetic acid, glycolic acid, malonic acid, and tartaric acid were chosen in the experiments. LMWOAs enhanced the mobility of GO by electrostatic/steric repulsion. In addition, they competed with GO for limited deposition sites on grain surfaces. The effects of organic acids on the transport of GO strongly depended on organic acid species. In general, the transport enhancement effects followed the order of tartaric acid > malonic acid > glycolic acid > acetic acid; this difference may be related to the number and type of functional groups of organic acids. Different LMWOAs enhanced the transport of GO in goethite-coated sand to a larger extent than did in kaolinite-coated sand under the test conditions; this was likely related to the differences of physicochemical characteristics between goethite and kaolinite. Organic acids significantly inhibited the deposition of GO at 0.5 mM Ca2+; this was possible that Ca2+ enhanced adsorption of organic acids by complexing with the surface O-functionalities of both LMWOAs and sand grain. Consequently, more organic acid molecules competed with GO for deposition sites on grain surfaces. Additionally, a two-site transport model was used to fit the transport data. Our findings have important implications for the understanding of the deposition and fate of GO in soil especially in rhizosphere environments where various low-molecular-weight organic acids are active.
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Affiliation(s)
- Jiuyan Chen
- Ecology Institute of the Shandong Academy of Sciences, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
- Henan University Minsheng College, Kaifeng, 475004, China
| | - Taotao Lu
- Department of Hydrology, University of Bayreuth, 95440, Bayreuth, Germany
| | - Ying Wang
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
- Henan University Minsheng College, Kaifeng, 475004, China
| | - Jiaqi Li
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China
- Henan University Minsheng College, Kaifeng, 475004, China
| | - Xiaowen Fu
- Ecology Institute of the Shandong Academy of Sciences, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
| | - Zhichong Qi
- Ecology Institute of the Shandong Academy of Sciences, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China.
- Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, China.
| | - Qiang Zhang
- Ecology Institute of the Shandong Academy of Sciences, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China.
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18
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Adsorption and Desorption of Cd by Soil Amendment: Mechanisms and Environmental Implications in Field-Soil Remediation. SUSTAINABILITY 2018. [DOI: 10.3390/su10072337] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In China, 1/5 of the total farmland area is Cd-enriched; the wide occurrence of Cd-contaminated soil in China has already posed significant public health risk and deserves immediate action. In situ immobilization has been regarded as one of the most promising agricultural extension-technologies for remediating low-to-medium levels of heavy metal contaminated land in China. Although extensive research has been conducted to examine the effectiveness of different amendments on remediation of Cd-contaminated soils, the influence of changed soil properties on secondary release of Cd from Cd-amendment to soil is rarely known. The objective of this study was to evaluate the effectiveness of four soil amendments (denoted as Ad1, Ad2, Ad3 and Ad4, their main components being clay mineral, base mineral, humus and biochar, respectively) on reducing Cd availability and increasing Cd stability in soil. The maximum adsorption capacity of test amendments on Cd ranged from 7.47 to 17.67 mg g−1. The characterizations of test amendments before and after Cd loading provided the evidence that surface precipitation and ion exchange were the main reasons for Ad1 and Ad2 to adsorb Cd, and complexation was for Ad3 and Ad4. In addition, there was significant increase in the desorption percentages of Cd from amendments as pH decreased (from 7 to 1) or ion strength increased (from 0 to 0.2 M). Comparatively, Ad3 and Ad4 could be more effective for in situ immobilization of Cd in contaminated soils, due to their high adsorption capacities (12.82 and 17.67 mg g−1, respectively) and low desorption percentages (4.46–6.23%) at pH from 5 to 7 and ion strengths from 0.01 to 0.1 mol L−1. The results obtained in this study could provide a guideline for in-situ remediation of Cd polluted field-soil in China.
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Karimzadeh L, Lippmann-Pipke J, Franke K, Lippold H. Mobility and transport of copper(II) influenced by the microbial siderophore DFOB: Column experiment and modelling. CHEMOSPHERE 2017; 173:326-329. [PMID: 28122291 DOI: 10.1016/j.chemosphere.2017.01.058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 01/09/2017] [Accepted: 01/11/2017] [Indexed: 06/06/2023]
Abstract
Acid Cu leaching from the European Kupferschiefer ore deposits is a challenge e.g. due to its high carbonate content. In this study, we investigated the transport behaviour of Cu under conditions related to a biohydrometallurgical leaching approach using neutrophil microorganisms in neutral to slightly alkaline solutions. We studied the effect of the microbial siderophore desferrioxamineB (DFOB) as a model leaching organic ligand on Cu mobility in column experiments with kaolinite. The results revealed that DFOB strongly enhances Cu mobility. The breakthrough of Cu occurs considerably earlier in the presence of DFOB than in the absence of the organic ligand. Furthermore, complete elution of Cu was observed at 5 pore volume exchanges faster compared to elution with deionized water. The established geochemical transport model shows good agreement with the experimental data and suggests a maximum efficiency at a Cu to DFOB molar ratio of 1:1. In addition, results of modelling revealed that in the absence of the ligand, a pH increase from 6.5 to 8.5 significantly retarded Cu breakthrough, whereas in the presence of DFOB, Cu breakthrough curves were nearly insensitive to pH changes and close to the breakthrough curve of a non-reactive tracer.
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Affiliation(s)
- Lotfollah Karimzadeh
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Reactive Transport Division, Permoserstr. 15, 04318 Leipzig, Germany.
| | - Johanna Lippmann-Pipke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Reactive Transport Division, Permoserstr. 15, 04318 Leipzig, Germany
| | - Karsten Franke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Reactive Transport Division, Permoserstr. 15, 04318 Leipzig, Germany
| | - Holger Lippold
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Reactive Transport Division, Permoserstr. 15, 04318 Leipzig, Germany
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Mwamba TM, Li L, Gill RA, Islam F, Nawaz A, Ali B, Farooq MA, Lwalaba JL, Zhou W. Differential subcellular distribution and chemical forms of cadmium and copper in Brassica napus. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2016; 134P1:239-249. [PMID: 27639199 DOI: 10.1016/j.ecoenv.2016.08.021] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 08/18/2016] [Accepted: 08/26/2016] [Indexed: 05/20/2023]
Abstract
Metal subcellular fractions and chemical profile highly reflect their level of toxicity to plants. Cadmium and Cu, two different but potentially toxic metals, were compared in the present study for their subcellular distribution and chemical forms in two Brassica napus cultivars (Zheda 622 and ZS 758). Five-week-old seedlings were hydroponically exposed to metal stress and analyzed after 15 days of treatment. In both cultivars, Cd was less retained at cell wall, thus major part of Cd accumulated in the soluble fraction. By contrast, handsome amount of Cu was sequestrated in both cell wall and vacuole containing fraction. Across sensitive organelles, Cu preferentially accumulated in chloroplasts, while Cd was equally distributed in chloroplasts and mitochondria; the two metals intruded nucleus at lesser degree. Further, Cd and Cu differentially interacted with various cellular ligands, and the extent of interaction was higher in the tolerant cultivar ZS 758. Copper was remarkably sequestrated by phosphates, and secondarily by peptide-ligands; inversely, the role of phosphates was secondary in Cd complexation, which was mainly achieved by peptide-ligands. Additional amount of Cu was aggregated with oxalates, but oxalate-bound Cd was scarcely detected. Current results have demonstrated varied toxicological and detoxification pathways of Cd and Cu in B. napus, suggesting that the efficiency of different alleviation strategies could vary against Cd and Cu toxicity to plants.
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Affiliation(s)
- Theodore M Mwamba
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China; Faculty of Agriculture, Department of Crop Science, University of Lubumbashi, Lubumbashi 1825, Democratic Republic of the Congo
| | - Lan Li
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China
| | - Rafaqat A Gill
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China
| | - Faisal Islam
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China
| | - Amir Nawaz
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China; Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan 60000, Pakistan
| | - Basharat Ali
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China; Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Bonn 53115, Germany
| | - Muhammad A Farooq
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China
| | - Jonas L Lwalaba
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China; Faculty of Agriculture, Department of Crop Science, University of Lubumbashi, Lubumbashi 1825, Democratic Republic of the Congo
| | - Weijun Zhou
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou 310058, China.
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Najafi S, Jalali M. Effect of heavy metals on pH buffering capacity and solubility of Ca, Mg, K, and P in non-spiked and heavy metal-spiked soils. ENVIRONMENTAL MONITORING AND ASSESSMENT 2016; 188:342. [PMID: 27168329 DOI: 10.1007/s10661-016-5329-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 04/25/2016] [Indexed: 06/05/2023]
Abstract
In many parts of the world, soil acidification and heavy metal contamination has become a serious concern due to the adverse effects on chemical properties of soil and crop yield. The aim of this study was to investigate the effect of pH (in the range of 1 to 3 units above and below the native pH of soils) on calcium (Ca), magnesium (Mg), potassium (K), and phosphorus (P) solubility in non-spiked and heavy metal-spiked soil samples. Spiked samples were prepared by cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn) as chloride salts and incubating soils for 40 days. The pH buffering capacity (pHBC) of each sample was determined by plotting the amount of H(+) or OH(-) added (mmol kg(-1)) versus the related pH value. The pHBC of soils ranged from 47.1 to 1302.5 mmol kg(-1) for non-spiked samples and from 45.0 to 1187.4 mmol kg(-1) for spiked soil samples. The pHBC values were higher in soil 2 (non-spiked and spiked) which had higher calcium carbonate content. The results indicated the presence of heavy metals in soils generally decreased the solution pH and pHBC values in spiked samples. In general, solubility of Ca, Mg, and K decreased with increasing equilibrium pH of non-spiked and spiked soil samples. In the case of P, increasing the pH to about 7, decreased the solubility in all soils but further increase of pH from 7, enhanced P solubility. The solubility trends and values for Ca, Mg, and K did not differed significantly in non-spiked and spiked samples. But in the case of P, a reduction in solubility was observed in heavy metal-spiked soils. The information obtained in this study can be useful to make better estimation of the effects of soil pollutants on anion and cation solubility from agricultural and environmental viewpoints.
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Affiliation(s)
- Sarvenaz Najafi
- Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamadan, Iran.
| | - Mohsen Jalali
- Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamadan, Iran
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Tahervand S, Jalali M. Sorption, desorption, and speciation of Cd, Ni, and Fe by four calcareous soils as affected by pH. ENVIRONMENTAL MONITORING AND ASSESSMENT 2016; 188:322. [PMID: 27147235 DOI: 10.1007/s10661-016-5313-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 04/21/2016] [Indexed: 06/05/2023]
Abstract
The sorption, desorption, and speciation of cadmium (Cd), nickel (Ni), and iron (Fe) in four calcareous soils were investigated at the pH range of 2-9. The results indicated that sorption of Fe by four soils was higher than 80 % at pH 2, while in the case of Cd and Ni was less than 30 %. The most common sequence of metal sorption at pH 2-9 for four soils was in the order of Fe ≫ Ni > Cd. Cadmium and Ni sorption as a function of pH showed the predictable trend of increasing metal sorption with increase in equilibrium pH, while the Fe sorption trend was different and characterized by three phases. With regard to the order of Cd, Ni, and Fe sorption on soils, Cd and Ni showed high affinity for organic matter (OM), whereas Fe had high tendency for calcium carbonate (CaCO3). Results of metal desorption using 0.01 M NaCl demonstrated that metal sorption on soils containing high amounts of CaCO3 was less reversible in comparison to soils containing high OM. In general, Cd and Ni desorption curves were characterized by three phases; (1) the greatest desorption at pH 2, (2) the low desorption at pH 3-7, and (3) the least desorption at pH > 7. The MINTEQ speciation solubility program showed that the percentage of free metals declined markedly with increase of pH, while the percentage of carbonate and hydroxyl species increased. Furthermore, MINTEQ predicted that saturation index (SI) of metals increased with increasing pH.
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Affiliation(s)
- Samaneh Tahervand
- Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamedan, Iran.
| | - Mohsen Jalali
- Department of Soil Science, College of Agriculture, Bu-Ali Sina University, Hamedan, Iran
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Heavy Metal Contamination in Rice-Producing Soils of Hunan Province, China and Potential Health Risks. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:15584-93. [PMID: 26670240 PMCID: PMC4690941 DOI: 10.3390/ijerph121215005] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 11/29/2015] [Accepted: 11/29/2015] [Indexed: 12/16/2022]
Abstract
We studied Cd, Cr, As, Ni, Mn, Pb, and Hg in three agricultural areas of Hunan province and determined the potential non-carcinogenic and carcinogenic risks for residents. Soil and brown rice samples from Shimen, Fenghuang, and Xiangtan counties were analyzed by atomic absorption spectroscopy. Soil levels of Cd and Hg were greatest, followed by As and Ni. The mean concentrations of heavy metals in brown rice were Cd 0.325, Cr 0.109, As 0.344, Ni 0.610, Mn 9.03, Pb 0.023, and Hg 0.071 mg/kg, respectively. Cd and Hg had greater transfer ability from soil to rice than the other elements. Daily intake of heavy metals through brown rice consumption were estimated to be Cd 2.30, Cr 0.775, As 2.45, Ni 4.32, Pb 0.162, Mn 64.6 and Hg 0.503 µg/(kg·day), respectively. Cd, Hg and As Hazard Quotient values were greater than 1 and Cd, Cr, As and Ni Cancer Risk values were all greater than 10(-4). The total non-carcinogenic risk factor was 14.6 and the total carcinogenic risk factor was 0.0423. Long-term exposure to heavy metals through brown rice consumption poses both potential non-carcinogenic and carcinogenic health risks to the local residents.
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