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Costa ASPN, Nascimento ALA, Botero WG, Carvalho CM, Tonholo J, Santos JCC, Anunciação DS. Interaction between humic substances and arsenic species simulating environmental conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149779. [PMID: 34525680 DOI: 10.1016/j.scitotenv.2021.149779] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 08/04/2021] [Accepted: 08/16/2021] [Indexed: 06/13/2023]
Abstract
The importance of evaluating how natural organic matter influences the mobility of arsenic species in an ecosystem is an environmental concern. This work aimed to evaluate the interaction between humic substances (HS) and four arsenic species of high toxicity [As(III), As(V), MMA(V), and DMA(V)] (HS-As) under the influence of HS concentration and pH. Next, the complexing capacity (CC) of HS by As(III) was determined in function of pH, ionic strength and co-existing ions. The free arsenic (Asfree) was determined after a tangential flow ultrafiltration procedure by hydride generation atomic fluorescence spectrometry. The better HS-As interactions for As(III) and As(V) at pH 10.5 reached 52% and 61%, respectively. The increase in pH and ionic strength, as well as co-existing ions increased the CC, which reached 1.57 mg of As(III) g-1 HS. We proposed a HS-As interaction model based on the inner and outer binding sites of HS from these results. The inner sites were occupied through hydrogen bonds, Pearson acid-base, hydrophobic, and van der Waals interactions for trivalent arsenic species, while the interactions through the outer sites for pentavalent arsenic species were mostly by hydrogen bonds and electrostatic forces. According to ecotoxicological studies against Artemia salina, the presence of HS decreased the toxicity of As(III) and As(V) as the lethal concentration increased from 5.81 to 8.82 mg L-1 and from 8.82 to 13.37 mg L-1, respectively. From the results through the proposed model, it was possible to successfully understand the interaction dynamic between soil HS and As(III), As(V), MMA(V) and DMA(V) under simulated environmental conditions.
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Affiliation(s)
- Aryanna S P N Costa
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil
| | - Amanda L A Nascimento
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil
| | - Wander G Botero
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil
| | - Cenira M Carvalho
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil
| | - Josealdo Tonholo
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil
| | - Josué C C Santos
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil.
| | - Daniela S Anunciação
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Campus A. C. Simões, 57072-900 Maceió, AL, Brazil.
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Patyal V, Jaspal D, Khare K. Materials for phosphorous remediation: a review. PHOSPHORUS SULFUR 2021. [DOI: 10.1080/10426507.2021.1989683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Vandana Patyal
- Department of Civil Engineering, Symbiosis Institute of Technology (SIT), Symbiosis International (Deemed University), Pune, Maharashtra, India
| | - Dipika Jaspal
- Department of Applied Science, Symbiosis Institute of Technology (SIT), Symbiosis International (Deemed University), Pune, Maharashtra, India
| | - Kanchan Khare
- Department of Civil Engineering, Symbiosis Institute of Technology (SIT), Symbiosis International (Deemed University), Pune, Maharashtra, India
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Yuvaraj A, Govarthanan M, Karmegam N, Biruntha M, Kumar DS, Arthanari M, Govindarajan RK, Tripathi S, Ghosh S, Kumar P, Kannan S, Thangaraj R. Metallothionein dependent-detoxification of heavy metals in the agricultural field soil of industrial area: Earthworm as field experimental model system. CHEMOSPHERE 2021; 267:129240. [PMID: 33341732 DOI: 10.1016/j.chemosphere.2020.129240] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/23/2020] [Accepted: 12/04/2020] [Indexed: 06/12/2023]
Abstract
Earthworms are known to reclaim soil contamination and maintain soil health. In the present study, the concentration of DTPA extractable heavy metals, Cd, Cu, Cr, Pb, and Zn in vermicasts and tissues of the earthworms (anecic: Lampito mauritii; epigeic: Drawida sulcata) collected from the soils of four different industrial sites, Site-I (Sago industry), Site-II (Chemplast industry), Site-III (Dairy industry) and Site-IV (Dye industry) have been studied. The heavy metals in industrial soils recorded were 0.01-326.42 mg kg-1 with higher Cu, Cr, and Zn contents while the vermicasts showed lower heavy metal loads with improved physicochemical properties and elevated humic substances. The higher humic substances dramatically decreased the heavy metals in the soil. The bioaccumulation factors of heavy metals (mg kg-1) are in the order: Zn (54.50) > Cu (17.43) > Cr (4.54) > Pb (2.24) > Cd (2.12). The greatest amount of metallothionein protein (nmol g-1) was recorded in earthworms from Site-IV (386.76) followed by Site-III (322.14), Site-II (245.82), and Site-I (232.21). Drawida sulcata can produce a considerable amount of metallothionein protein than Lampito mauritii as the metallothionein production is dependent upon the presence of pollutants. The molecular docking analysis indicates a binding score of 980 for Cd, Cr and Cu, and 372 for Zn. Pb may bind with a non-metallothionein protein of earthworms and bio-accumulated in the internal chloragogenous tissues. Metallothionein neutralizes the metal toxicity and controls the ingestion of essential elements.
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Affiliation(s)
- Ananthanarayanan Yuvaraj
- Vermitechnology and Ecotoxicology Laboratory, Department of Zoology, School of Life Sciences, Periyar University, Salem, Tamil Nadu, 636 011, India
| | - Muthusamy Govarthanan
- Department of Environmental Engineering, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Natchimuthu Karmegam
- Department of Botany, Government Arts College (Autonomous), Salem, Tamil Nadu, 636 007, India
| | - Muniyandi Biruntha
- Vermitechnology Laboratory, Department of Animal Health and Management, Alagappa University, Karaikudi, Tamil Nadu, 630 003, India
| | | | - Mohan Arthanari
- Department of Zoology, Kandaswami Kandar's College, Namakkal, Tamil Nadu, 638 182, India
| | - Rasiravathanahalli Kaveriyappan Govindarajan
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control and Integrative Microbiology Research Center, South China Agricultural University, Guangzhou, 510642, PR China
| | - Sudipta Tripathi
- Department of Agricultural Chemistry and Soil Science, Institute of Agricultural Science, University of Calcutta Baruipur, Kolkata, 700 144, India
| | - Swayambhu Ghosh
- Soils Department, Tocklai Tea Research Institute, Tea Research Association, Jorhat, Assam, 785 008, India
| | - Ponnuchamy Kumar
- Department of Animal Health and Management, Alagappa University, Karaikudi, Tamil Nadu, 630 003, India
| | - Soundarapandian Kannan
- Cancer Nanomedicine Laboratory, Department of Zoology, School of Life Sciences, Periyar University, Salem, Tamil Nadu, 636 011, India
| | - Ramasundaram Thangaraj
- Vermitechnology and Ecotoxicology Laboratory, Department of Zoology, School of Life Sciences, Periyar University, Salem, Tamil Nadu, 636 011, India.
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Audette Y, Smith DS, Parsons CT, Chen W, Rezanezhad F, Van Cappellen P. Phosphorus binding to soil organic matter via ternary complexes with calcium. CHEMOSPHERE 2020; 260:127624. [PMID: 32683029 DOI: 10.1016/j.chemosphere.2020.127624] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 07/03/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
Soil organic matter (SOM) is known to exert a major control on the mobility and bioavailability of cationic nutrients. However, the role of SOM in the fate of anionic nutrients, especially phosphorus (P), is less well characterized. The objectives of this study were to (1) compare the formation of binary complexes of calcium (Ca) with humic acids (HA) extracted from two contrasting soils, and (2) determine if binary HA-Ca complexes could incorporate P by forming ternary HA-Ca-P complexes. The Ca binding capacities of the HA extracted from an agricultural organic soil (AOS) and a pristine riparian soil (RS) were measured via potentiometric titrations; the formation of ternary complexes was analyzed by size fractionation using MWCO tubes. Proton and Ca binding capacities of RS-HA were higher than AOS-HA, and pH had a weaker effect on Ca binding to RS-HA. These differences are consistent with lower proportions of aromatic groups, and a higher proportion of alkyl groups derived from 13C NMR spectroscopy. Together, the NMR, titration and MWCO data indicate that Ca binds to RS-HA through monodentate complexes and electrostatic attraction that are capable of binding P producing ternary complexes. In contrast, at pH 8.5 Ca forms bidentate complexes with AOS-HA, which do not provide bridging positions to incorporate P. Overall, our results imply that the formation of HA-Ca and HA-Ca-P complexes depend on the structure of the HA, and that complexation to HA may play an important role in the fate of P in terrestrial and aquatic environments.
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Affiliation(s)
- Yuki Audette
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada; School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
| | - D Scott Smith
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - Christopher T Parsons
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada
| | - Weibin Chen
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
| | - Fereidoun Rezanezhad
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada
| | - Philippe Van Cappellen
- Ecohydrology Research Group, Department of Earth and Environmental Sciences and Water Institute, University of Waterloo, Waterloo, ON, N2L 2G1, Canada
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Morozesk M, Bonomo MM, Souza IDC, Rocha LD, Duarte ID, Martins IO, Dobbss LB, Carneiro MTWD, Fernandes MN, Matsumoto ST. Effects of humic acids from landfill leachate on plants: An integrated approach using chemical, biochemical and cytogenetic analysis. CHEMOSPHERE 2017; 184:309-317. [PMID: 28601664 DOI: 10.1016/j.chemosphere.2017.06.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 05/30/2017] [Accepted: 06/03/2017] [Indexed: 06/07/2023]
Abstract
Biological process treatment of landfill leachate produces a significant amount of sludge, characterized by high levels of organic matter from which humic acids are known to activate several enzymes of energy metabolism, stimulating plant growth. This study aimed to characterize humic acids extracted from landfill sludge and assess the effects on plants exposed to different concentrations (0.5, 1, 2 and 4 mM C L-1) by chemical and biological analysis, to elucidate the influence of such organic material and minimize potential risks of using sludge in natura. Landfill humic acids showed high carbon and nitrogen levels, which may represent an important source of nutrients for plants. Biochemical analysis demonstrated an increase of enzyme activity, especially H+-ATPase in 2 mM C L-1 landfill humic acid. Additionally, cytogenetic alterations were observed in meristematic and F1 cells, through nuclear abnormalities and micronuclei. Multivariate statistical analysis provided integration of physical, chemical and biological data. Despite all the nutritional benefits of humic acids and their activation of plant antioxidant systems, the observed biological effects showed concerning levels of mutagenicity.
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Affiliation(s)
- Mariana Morozesk
- Physiological Science Department, Federal University of Sao Carlos, Av. Washington Luiz, Km 235, 13565-905, Sao Carlos, Sao Paulo, Brazil
| | - Marina Marques Bonomo
- Physiological Science Department, Federal University of Sao Carlos, Av. Washington Luiz, Km 235, 13565-905, Sao Carlos, Sao Paulo, Brazil
| | - Iara da Costa Souza
- Physiological Science Department, Federal University of Sao Carlos, Av. Washington Luiz, Km 235, 13565-905, Sao Carlos, Sao Paulo, Brazil
| | - Lívia Dorsch Rocha
- Biological Science Department, Federal University of Espirito Santo, Av. Fernando Ferrari, 514, 29075-910, Vitoria, Espirito Santo, Brazil
| | - Ian Drumond Duarte
- Biological Science Department, Federal University of Espirito Santo, Av. Fernando Ferrari, 514, 29075-910, Vitoria, Espirito Santo, Brazil
| | - Ian Oliveira Martins
- Biological Science Department, Federal University of Espirito Santo, Av. Fernando Ferrari, 514, 29075-910, Vitoria, Espirito Santo, Brazil
| | - Leonardo Barros Dobbss
- Institute of Agricultural Sciences, Federal University of Jequitinhonha and Mucuri Valleys, Avenida Vereador Joao Narciso, 1380, 38610-000, Unai, Minas Gerais, Brazil
| | | | - Marisa Narciso Fernandes
- Physiological Science Department, Federal University of Sao Carlos, Av. Washington Luiz, Km 235, 13565-905, Sao Carlos, Sao Paulo, Brazil
| | - Silvia Tamie Matsumoto
- Biological Science Department, Federal University of Espirito Santo, Av. Fernando Ferrari, 514, 29075-910, Vitoria, Espirito Santo, Brazil.
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Hatano KI, Kanazawa K, Tomura H, Yamatsu T, Tsunoda KI, Kubota K. Molasses melanoidin promotes copper uptake for radish sprouts: the potential for an accelerator of phytoextraction. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:17656-17663. [PMID: 27239675 DOI: 10.1007/s11356-016-6904-x] [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: 03/09/2016] [Accepted: 05/16/2016] [Indexed: 06/05/2023]
Abstract
Phytoextraction has been proposed as an alternative remediation technology for heavy metal contamination, and it is well known that chelators may alter the toxicity of heavy metals and the bioavailability in plants. Our previous work demonstrated that an adsorbent-column chromatography can effectively separate melanoidin-like product (MLP) from sugarcane molasses. The aim of this study was to examine the chelating property of MLP and to evaluate the facilitatory influence on the phytoextraction efficiency of Japanese radish. The result showed that MLP binds to all the metal ions examined and the binding capacity of MLP toward Cu(2+) seems to be the highest among them. The metal detoxification by MLP followed the order of Pb(2+) > Zn(2+) > Ni(2+) > Cu(2+) > Fe(2+) > Cd(2+) > Co(2+). Furthermore, in the phytoextraction experiment using copper sulfate, the application of MLP accelerated the detoxification of copper and the bioavailability in radish sprouts. Thus, these results suggest that MLP possesses the potential for an accelerator of phytoextraction in the copper-contaminated media.
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Affiliation(s)
- Ken-Ichi Hatano
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan.
| | - Kazuki Kanazawa
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
| | - Hiroki Tomura
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
| | - Takeshi Yamatsu
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
| | - Kin-Ichi Tsunoda
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
| | - Kenji Kubota
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma, 376-8515, Japan
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Chen Y, Xie T, Liang Q, Liu M, Zhao M, Wang M, Wang G. Effectiveness of lime and peat applications on cadmium availability in a paddy soil under various moisture regimes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:7757-7766. [PMID: 26755172 DOI: 10.1007/s11356-015-5930-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 12/04/2015] [Indexed: 06/05/2023]
Abstract
In paddy soils, amendments and moisture play important role in the immobilization of cadmium (Cd). The effects of applying lime, peat, and a combination of both on soil Eh, pH, and Cd availability in contaminated soils were investigated under wetted (80 ± 5 % of water holding capacity) and flooded (completely submerged) conditions. In wetted soils, there was little change in Eh, compared to flooded soils where Eh reduced rapidly. Amendments of lime only or in a mixture with peat increased soil pH to different degrees, depending on the lime application rate. However, peat addition only slightly affected soil pH. The decreased Cd availability in flooded soils was related to submergence duration and was significantly lower than that in wetted soils after 14 days. Liming wetted and flooded soils decreased exchangeable Cd and increased carbonates or Fe-Mn oxides bound fractions, while peat addition transformed Cd from carbonates to organic matter bound fractions. The combined application of peat and lime generally showed better inhibitory effects on the availability of Cd than separately application of lime or peat. Higher application rates of lime, peat, or their mixture were more effective at reducing Cd contamination in flooded soil. This indicates that application of peat and lime mixture under flooded conditions was most effective for in situ remediation of Cd-contaminated soils. Further studies are required to assess the long-term effectiveness of the peat and lime mixture on Cd availability in paddy soils.
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Affiliation(s)
- Yanhui Chen
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Tuanhui Xie
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Qiaofeng Liang
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Mengjiao Liu
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Mingliu Zhao
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Mingkuang Wang
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Guo Wang
- College of Resources and Environmental Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
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Bertoli AC, Garcia JS, Trevisan MG, Ramalho TC, Freitas MP. Interactions fulvate-metal (Zn²⁺, Cu²⁺ and Fe²⁺): theoretical investigation of thermodynamic, structural and spectroscopic properties. Biometals 2016; 29:275-85. [PMID: 26857737 DOI: 10.1007/s10534-016-9914-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 02/03/2016] [Indexed: 11/26/2022]
Abstract
The use of theoretical calculation to determine structural properties of fulvate-metal complex (zinc, copper and iron) is here related. The species were proposed in the ratio 1:1 and 2:1 for which the molecular structure was obtained through the semi-empirical method PM6. The calculation of thermodynamic stability ([Formula: see text]) predicted that the iron complex were more exo-energetic. Metallic ions were coordinated to the phtalate groups of the model-structure of fulvic acid Suwannee River and the calculations of vibrational frequencies suggested that hydrogen bonds may help on the stability of the complex formation.
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Affiliation(s)
- Alexandre C Bertoli
- Instituto de Química, Universidade Federal de Alfenas, UNIFAL, Alfenas, MG, 37130-000, Brazil.
| | - Jerusa S Garcia
- Instituto de Química, Universidade Federal de Alfenas, UNIFAL, Alfenas, MG, 37130-000, Brazil
| | - Marcello G Trevisan
- Instituto de Química, Universidade Federal de Alfenas, UNIFAL, Alfenas, MG, 37130-000, Brazil
| | - Teodorico C Ramalho
- Departamento de Química, Universidade Federal de Lavras, Lavras, MG, 37200-000, Brazil
| | - Matheus P Freitas
- Departamento de Química, Universidade Federal de Lavras, Lavras, MG, 37200-000, Brazil
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Shahid M, Pinelli E, Dumat C. Review of Pb availability and toxicity to plants in relation with metal speciation; role of synthetic and natural organic ligands. JOURNAL OF HAZARDOUS MATERIALS 2012; 219-220:1-12. [PMID: 22502897 DOI: 10.1016/j.jhazmat.2012.01.060] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 01/17/2012] [Accepted: 01/19/2012] [Indexed: 05/03/2023]
Abstract
Biogeochemical behavior of lead (Pb), a persistent hazardous pollutant of environmental concern, strongly depends on its chemical speciation. Therefore, in this review, link between Pb speciation: presence of organic ligands and its environmental behavior has been developed. Both, biogeochemical and ecotoxicological data are discussed in environmental risk assessment context and phytoremediation studies. Three kinds of organic ligands selected for this review include: (1) ethylene diamine tetra-acetic acid (EDTA), (2) low molecular weight organic acids (LMWOAs) and (3) humic substances (HSs). The review highlights the effect of Pb speciation on: (i) Pb fate and behavior in soil; (ii) Pb plant uptake and accumulation in different plant parts; and (iii) Pb-induced phyto-toxicity. Effects of organic ligands on Pb speciation are compared: how they can change Pb speciation modifying accordingly its fate and biogeochemistry in soil-plant system? EDTA forms soluble, stable and phytoavailable Pb-chelates due to high binding Pb affinity. LMWOAs can solubilize Pb in soil by decreasing soil pH or increasing soil organic contents, but have little effect on its translocation. Due to heterogeneous structure, HSs role is complex. In consequence Pb speciation knowledge is needed to discuss phyto-toxicity data and improved soil phytoremediation techniques.
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Affiliation(s)
- M Shahid
- Université de Toulouse, INP-ENSAT, Castanet-Tolosan, France
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