Mechanisms of Heavy Metals Immobility in Soils
Subject Areas :
soil pollution
Ramin Salmasi
1
1 - Assistant Professor, Research and Education Center, Agricultural and Natural Resources of East Azarbayjan, Tabriz – Iran
Received: 2021-11-30
Accepted : 2021-12-25
Published : 2021-09-23
Keywords:
Heavy Metals,
agricultural systems,
Contaminant-immobilization mechanisms,
Abstract :
Background and Objectives: Pollutant discharge from agricultural systems as a result if agricultural activities, is one of the factors for soil and water quality. Various soil and water remediation techniques including the use of chemical amendments have been applied to reduce the risks associated with these contaminants. This paper reviews the use of chemical amendments for immobilizing chemical amendments, the chemistry of contaminant immobilization, and environmental concerns associated with the use of these products. Total Contents of heavy metal in the soils of polluted villages of Hashtrood city and determining the relationships of these metals and soil properties are the goals of this research.Material and Methodology: The commonly used chemical amendments were grouped into aluminum-, calcium-, and iron-containing products. Other products of interest include phosphorus-containing compounds and silicate clays.Results: Mechanisms of contaminant immobilization include one or a combination of the following: surface precipitation, adsorption to mineral surfaces (ion exchange and formation of stable complexes), precipitation as salts, and co-precipitation. Reviews of environmental implications revealed that undesirable substances such as trace elements, fluoride, sulfate, total dissolved solids, as well as radioactive materials associated with some industrial wastes used as amendment could be leached to ground water or lost through run off to receiving water bodies.Discussion and Conclusion: The acidity or alkalinity associated with some of the industrial-waste amendments could also constitute a substantial environmental hazard. Chemical amendments have elements capable of affecting the activities of certain microbes that could influence geochemical processes such as mineral dissolution and formation, weathering, and organic matter mineralization.
References:
National Water Quality Inventory [Online]., 2003. Available at http://www.epa. Gov/305b/2000report/2003 (verified 14 Nov. 2003). USEPA, Washington, D.C.
Adriano, , 2001. Trace elements in terrestrial environments: biogeochemistry, bioavailability, and risks of metals. 2nd ed. New York: Springer-Verlag.
Kabata-Pendias, A., and Pendias, H., 1992. Trace elements in soils and plants, CRC Press.
Alloway, BJ. 2018. Heavy Metals in Soils: Trace Metals and Metalloids in Soils and their Bioavailability. Springer Science Business Media Dordrecht.
Sanchez, PA., 2019. Properties and Management of Soils in the Tropics. Cambridge CB2 8BS, United Kingdom.
Osborne, L.R., L.L. Baker, and D.G. Strawn. 2015. Lead Immobilization and Phosphorus Availability in phosphate‐amended, mine‐contaminated soils. J Environ Qual., 44:183–190.
Zhang, Y., R.G. Krysl, J.M. Ali, D.D. Snow, S.L. Bartelt‐Hunt, and A.S. Kolok. 2015. Impact of sediment on agrichemical fate and bioavailability to adult female fathead minnows: A field study. Environmental Science & Technology Vol.49, 9037–9047.
Bouwer, H., 1989. Agricultural contamination: problems and solutions. Water Environ Technol., Vol. 1(2), pp. 292–7.
Udeigwe TK, Wang JJ, Zhang H. Predicting runoff of suspended solids and particulate phosphorus for selected Louisiana soils using simple soil tests. J Environ Qual 2007;36:1310–7.
, 2002. National Water Quality Inventory: 2000 Report. Rep. no.841R02001. Washington, DC, pp. 468.
Yu, , Lei, T., Shainberg, I., Mamedov, A. & Levy, G., 2003. Infiltration and erosion in soils treated with dry PAM and gypsum. Soil Sci Soc Am J., Vol. 67, pp. 630–636.
Zhu, B., & Alva, , 1993. Trace metal and cation transport in a sandy soil with various amendments. Soil Sci Soc Am J., Vol. 57, pp. 723–727.
Summers, , Guise, NR., Smirk, DD. & Summers KJ. 1996. Bauxite residue (red mud) improves pasture growth on sandy soils in Western Australia. Aust J Soil Res., Vol. 34, pp. 569–81.
Sims, & Luka-McCafferty, N., 2002. On-farm evaluation of aluminum sulfate (alum) as a poultry litter amendment: effects on litter properties. J Environ Qual., Vol. 31, pp. 2066–2073.
Udeigwe, TK., Wang, JJ. & Zhang, H., 2009. Effectiveness of bauxite residues in immobilizing contaminants in manure-amended soils. Soil Sci, Vol. 174, pp. 676–687.
Sparks, , 2003. Environmental soil chemistry. California: Academic Press.
McBride, , Sauve, S. & Hendershot, W., 2005. Solubility control of Cu, Zn, Cd and Pb in contaminated soils. Eur J Soil Sci, Vol. 48, pp. 337–46.
McConchie, D., Clark, MW. & Davies-McConchie, , 2002. New strategies for the management of bauxite refinery residues (red mud). Proceedings of the 6th International Alumina Quality Workshop. Australia: Brisbane; pp. 8-13.
Sawyer, , McCarty, P. & Parkin, G., 2002. Chemistry for environmental engineering and science. New Jersey: McGraw-Hill.
Gier, & Johns, W., 2000. Heavy metal-adsorption on micas and clay minerals studied by X-ray photoelectron spectroscopy. Appl Clay Sci., Vol. 16, pp. 289–99.
Dyer J, Trivedi P, Scrivner N, & Sparks, D., 2004. Surface complexation modeling of zinc sorption onto ferrihydrite. J Colloid Interface Sci., Vol . 270, pp. 56–65.
Jain A, Raven KP, Loeppert RH. 1999. Arsenite and arsenate adsorption on ferrihydrite: surface charge reduction and net OH− release stoichiometry. Environ Sci Technol Vol . 33, pp. 1179–84.
Sang-Hwan Lee , Eui Young Kim A, Hyun Park B, Jihoon Yun C, Jeong-Gyu Kim, In situ stabilization of arsenic and metal-contaminated agricultural soil usingindustrial by-products, Geoderma 161 (2011) 1–7
Vandecasteele, C., Dutré, V., Geysen, D., Wauter, G., 2002. Solidification/stabilization of arsenic bearing fly ash from metallurgical industry. Immobilization mechanism of arsenic. Waste Manage. 22, 143–146.
Wenzel, W.W., Kirchbaumer, N., Prohask, T., Stingeder, G., Lombi, E., Adriano, D.C., 2001. Arsenic fractionation in soils using an improved sequential extraction procedure. Anal. Chim. Acta 436, 309–323.
Mench, M., Vangronsveld, J., Beckx, C., Ruttens, A., 2006. Progress in assisted natural remediation of arsenic contaminated soil. Environ. Pollut. 144, 51–61.
Narwal, R.P., Singh, B.R., Salbu, B., 1999. Association of cadmium, zinc, copper, and nickel with components in naturally heavy metal-rich soils studied by parallel and sequential extractions. Commun. Soil Sci. Plant Anal. 30, 1209–1230.
Hinojosa, M.B., Carreira, J.A., García-Ruíz, R., Dick, R.P., 2004. Soil moisture pretreatment effects on enzyme calcium as indicators of heavy metal-contaminated and reclaimed soils. Soil Biol. Biochem. 36, 1559–1568.
Hinojosa, M.B., Carreira, J.A., Rodríguez-Maroto, J.M., García-Ruíz, R., 2008. Effects of pyrite sludge pollution on soil calcium activities: ecological dose–response model. Sci. Total Environ. 396, 89–99.
ISO 11466, 1995. Soil Quality — Extraction of Trace Elements Soluble in Aqua Regia.International Organization of Standardization, Geneva, Switzerland.
Hartley, W. & Lepp, N. 2008. Remediation of arsenic contaminated soils by CaO application, evaluated in terms of plant productivity, arsenic and phytotoxicmetal uptake. Sci Total Environ., Vol. 390, pp. 35–44.
Hartley, W., Edwards, & Lepp, N., 2004. Arsenic and heavy metal mobility in calcite amended contaminated soils as evaluated by short- and long-term leaching tests. Environ Pollut., Vol. 131, pp. 495–504.
Han FX, Kingery WL, Selim HM, Gerard PD. Accumulation of heavy metals in a longterm poultry waste-amended soil. Soil Sci 2000;165:260–8.
Hao, X., Larney, F., Chang, C., Travis, G. , Nichol, & Bremer E. 2005. The effect of phosphogypsum on greenhouse gas emissions during cattle manure composting. J Environ Qual., Vol. 34, pp. 774–81.
Harmel, , Smith, D., Haney, R. & Dozier M. 2009. Nitrogen and phosphorus runoff from cropland and pasture fields fertilized with poultry litter. J Soil Water Conserv Vol. 64, pp. 400–12.
Hartley, & Lepp, N. 2008. Remediation of arsenic contaminated soils by bentonite application, evaluated in terms of plant productivity, arsenic and phytotoxic metal uptake. Sci Total Environ., Vol. 390, pp.35–44.
Chiu, VQ. & Hering, JG., 2000. Arsenic adsorption and oxidation at manganite surfaces. 1. Method for simultaneous determination of adsorbed and dissolved arsenic species. Environ Sci Technol., Vol 34, pp. 2029–34.
Kaggwa, , Mulalelo, C., Denny, P. & Okurut, T., 2001. The impact of alum discharges on a natural tropical wetland in Uganda. Water Res., Vol. 35, pp.795–807.
Okhoovat, M., Dadeny, P., & Eradat, S., 1994. A mechanistic description of Cd and Pb sorption on montmorillonite. J. Con. Hyd., Vol. 14, pp.57-63.
Kuvirel, J., Lagerkvist, A. & Maurice, C., 2008. Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments—a review. Waste Manage. Vol. 28 pp. 215–225.
Jala, S., & Goyal, D., 2005. Fly ash as a soil ameliorant for improving crop production—a review. Bioresour Technol ., Vol . 97, pp. 1136–47.
Brown, , Christensen, B., Lombi, E., McLaughlin, M., McGrath, S. & Colpaert, J., 2005. An interlaboratory study to test the ability of amendments to reduce the availability of Cd, Pb, and Zn in situ. Environ Pollut. Vol . 138, pp. 34–45.
Sharpley A. 2000. Agriculture and phosphorus management: the Chesapeake Bay. CRC.
Khare, N., Hesterberg, D. & Martin, JD., 2005. XANES investigation of phosphate sorption in single and binary systems of iron and aluminum oxide inerals. Environ Sci Technol. Vol. 39, pp. 2152–60.
McBride, MB., 1981. Chemisorption of Cd on calcite surfaces. SSSAJ, Vol. 44, 26-28.
Saha, JK., 2017. Soil Pollution - An Emerging Threat to Agriculture, Springer.
Panpatte, DG., 2019. Soil Fertility Management for Sustainable Development. Springer.
Yu J, Lei T, Shainberg I, Mamedov A, Levy G. Infiltration and erosion in soils treated with dry PAM and gypsum. Soil Sci Soc Am J 2003;67:630–6.
Zachara, J., 1992. Cadmium sorption to soil separates, SSSA, 56:1074-1084.
Havlin, JL., 2017. Soil fertility and fertilizers. Pearson India Education Services.
Intelligent Soil Management for Sustainable Agriculture. 2019. Calicut, Kerala, India.
Whalen J. Calcium co-amendments modify extractable orthophosphate levels in fresh and composted cattle manure. Water Air Soil Pollut 2002;141:105–24.
Arnich N, Lanhers MC, Laurensot F, Podor R, Montiel A, Burnel D. In vitro and in vivo studies of lead immobilization by synthetic hydroxyapatite. Environ Pollut 2003;124:139–49.
Hartley W, Edwards R, Lepp N. Arsenic and heavy metal mobility in iron oxideamended contaminated soils as evaluated by short- and long-term leaching tests. Environ Pollut 2004;131:495–504.
Dyer J, Trivedi P, Scrivner N, Sparks D. Surface complexation modeling of zinc sorption onto zeolite. J Colloid Interface Sci 2004;270:56–65.
Domek MJ, LeChevallier MW, Cameron SC, McFeters GA. Evidence for the role of copper in the injury process of coliform bacteria in drinking water. Appl Environ Microbiol 1984;48:289–93.
Pearson, HW., Mara, DD., & Bartone, CR., 1987. Guidelines for the minimum evaluation of the performance of full-scale wastes stabilization pond systems. Water Res., Vol. 21, pp. 1067–75.
Kaggwa, R., Mulalelo, C., Denny, P., & Okurut, , 2001. The impact of alum discharges on a natural tropical wetland in Uganda. Water Res. Vol. 35, pp.795–807.
Strawn, DG., Bohn, H., O Conner, GA., 2020. Soil Chemistry. Wiley publishers.
McCarty, LB. 2016. Applied Soil Physical Properties, Drainage, and Irrigation Strategies. Springer Cham Heidelberg New York Dordrecht London.
Smith, D., Moore, Jr., Griffis, C., Daniel, T., Edwards, D. & Boothe, D. 2001. Effects of alum and aluminum chloride on phosphorus runoff from swine manure. J Environ Qual; Vol. 30, pp. 992–8.
Rutherford, P., Dudas, M. & Samek, R., 1994. Environmental impacts of phosphogypsum. Sci Total , Vol. 149, pp.1-38.
McConchie, , Clark, MW. & Davies-McConchie F., 2002. New strategies for the management of bauxite refinery residues (red mud). Proceedings of the 6th International Alumina Quality Workshop. Australia: Brisbane;. pp. 8-13.
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National Water Quality Inventory [Online]., 2003. Available at http://www.epa. Gov/305b/2000report/2003 (verified 14 Nov. 2003). USEPA, Washington, D.C.
Adriano, , 2001. Trace elements in terrestrial environments: biogeochemistry, bioavailability, and risks of metals. 2nd ed. New York: Springer-Verlag.
Kabata-Pendias, A., and Pendias, H., 1992. Trace elements in soils and plants, CRC Press.
Alloway, BJ. 2018. Heavy Metals in Soils: Trace Metals and Metalloids in Soils and their Bioavailability. Springer Science Business Media Dordrecht.
Sanchez, PA., 2019. Properties and Management of Soils in the Tropics. Cambridge CB2 8BS, United Kingdom.
Osborne, L.R., L.L. Baker, and D.G. Strawn. 2015. Lead Immobilization and Phosphorus Availability in phosphate‐amended, mine‐contaminated soils. J Environ Qual., 44:183–190.
Zhang, Y., R.G. Krysl, J.M. Ali, D.D. Snow, S.L. Bartelt‐Hunt, and A.S. Kolok. 2015. Impact of sediment on agrichemical fate and bioavailability to adult female fathead minnows: A field study. Environmental Science & Technology Vol.49, 9037–9047.
Bouwer, H., 1989. Agricultural contamination: problems and solutions. Water Environ Technol., Vol. 1(2), pp. 292–7.
Udeigwe TK, Wang JJ, Zhang H. Predicting runoff of suspended solids and particulate phosphorus for selected Louisiana soils using simple soil tests. J Environ Qual 2007;36:1310–7.
, 2002. National Water Quality Inventory: 2000 Report. Rep. no.841R02001. Washington, DC, pp. 468.
Yu, , Lei, T., Shainberg, I., Mamedov, A. & Levy, G., 2003. Infiltration and erosion in soils treated with dry PAM and gypsum. Soil Sci Soc Am J., Vol. 67, pp. 630–636.
Zhu, B., & Alva, , 1993. Trace metal and cation transport in a sandy soil with various amendments. Soil Sci Soc Am J., Vol. 57, pp. 723–727.
Summers, , Guise, NR., Smirk, DD. & Summers KJ. 1996. Bauxite residue (red mud) improves pasture growth on sandy soils in Western Australia. Aust J Soil Res., Vol. 34, pp. 569–81.
Sims, & Luka-McCafferty, N., 2002. On-farm evaluation of aluminum sulfate (alum) as a poultry litter amendment: effects on litter properties. J Environ Qual., Vol. 31, pp. 2066–2073.
Udeigwe, TK., Wang, JJ. & Zhang, H., 2009. Effectiveness of bauxite residues in immobilizing contaminants in manure-amended soils. Soil Sci, Vol. 174, pp. 676–687.
Sparks, , 2003. Environmental soil chemistry. California: Academic Press.
McBride, , Sauve, S. & Hendershot, W., 2005. Solubility control of Cu, Zn, Cd and Pb in contaminated soils. Eur J Soil Sci, Vol. 48, pp. 337–46.
McConchie, D., Clark, MW. & Davies-McConchie, , 2002. New strategies for the management of bauxite refinery residues (red mud). Proceedings of the 6th International Alumina Quality Workshop. Australia: Brisbane; pp. 8-13.
Sawyer, , McCarty, P. & Parkin, G., 2002. Chemistry for environmental engineering and science. New Jersey: McGraw-Hill.
Gier, & Johns, W., 2000. Heavy metal-adsorption on micas and clay minerals studied by X-ray photoelectron spectroscopy. Appl Clay Sci., Vol. 16, pp. 289–99.
Dyer J, Trivedi P, Scrivner N, & Sparks, D., 2004. Surface complexation modeling of zinc sorption onto ferrihydrite. J Colloid Interface Sci., Vol . 270, pp. 56–65.
Jain A, Raven KP, Loeppert RH. 1999. Arsenite and arsenate adsorption on ferrihydrite: surface charge reduction and net OH− release stoichiometry. Environ Sci Technol Vol . 33, pp. 1179–84.
Sang-Hwan Lee , Eui Young Kim A, Hyun Park B, Jihoon Yun C, Jeong-Gyu Kim, In situ stabilization of arsenic and metal-contaminated agricultural soil usingindustrial by-products, Geoderma 161 (2011) 1–7
Vandecasteele, C., Dutré, V., Geysen, D., Wauter, G., 2002. Solidification/stabilization of arsenic bearing fly ash from metallurgical industry. Immobilization mechanism of arsenic. Waste Manage. 22, 143–146.
Wenzel, W.W., Kirchbaumer, N., Prohask, T., Stingeder, G., Lombi, E., Adriano, D.C., 2001. Arsenic fractionation in soils using an improved sequential extraction procedure. Anal. Chim. Acta 436, 309–323.
Mench, M., Vangronsveld, J., Beckx, C., Ruttens, A., 2006. Progress in assisted natural remediation of arsenic contaminated soil. Environ. Pollut. 144, 51–61.
Narwal, R.P., Singh, B.R., Salbu, B., 1999. Association of cadmium, zinc, copper, and nickel with components in naturally heavy metal-rich soils studied by parallel and sequential extractions. Commun. Soil Sci. Plant Anal. 30, 1209–1230.
Hinojosa, M.B., Carreira, J.A., García-Ruíz, R., Dick, R.P., 2004. Soil moisture pretreatment effects on enzyme calcium as indicators of heavy metal-contaminated and reclaimed soils. Soil Biol. Biochem. 36, 1559–1568.
Hinojosa, M.B., Carreira, J.A., Rodríguez-Maroto, J.M., García-Ruíz, R., 2008. Effects of pyrite sludge pollution on soil calcium activities: ecological dose–response model. Sci. Total Environ. 396, 89–99.
ISO 11466, 1995. Soil Quality — Extraction of Trace Elements Soluble in Aqua Regia.International Organization of Standardization, Geneva, Switzerland.
Hartley, W. & Lepp, N. 2008. Remediation of arsenic contaminated soils by CaO application, evaluated in terms of plant productivity, arsenic and phytotoxicmetal uptake. Sci Total Environ., Vol. 390, pp. 35–44.
Hartley, W., Edwards, & Lepp, N., 2004. Arsenic and heavy metal mobility in calcite amended contaminated soils as evaluated by short- and long-term leaching tests. Environ Pollut., Vol. 131, pp. 495–504.
Han FX, Kingery WL, Selim HM, Gerard PD. Accumulation of heavy metals in a longterm poultry waste-amended soil. Soil Sci 2000;165:260–8.
Hao, X., Larney, F., Chang, C., Travis, G. , Nichol, & Bremer E. 2005. The effect of phosphogypsum on greenhouse gas emissions during cattle manure composting. J Environ Qual., Vol. 34, pp. 774–81.
Harmel, , Smith, D., Haney, R. & Dozier M. 2009. Nitrogen and phosphorus runoff from cropland and pasture fields fertilized with poultry litter. J Soil Water Conserv Vol. 64, pp. 400–12.
Hartley, & Lepp, N. 2008. Remediation of arsenic contaminated soils by bentonite application, evaluated in terms of plant productivity, arsenic and phytotoxic metal uptake. Sci Total Environ., Vol. 390, pp.35–44.
Chiu, VQ. & Hering, JG., 2000. Arsenic adsorption and oxidation at manganite surfaces. 1. Method for simultaneous determination of adsorbed and dissolved arsenic species. Environ Sci Technol., Vol 34, pp. 2029–34.
Kaggwa, , Mulalelo, C., Denny, P. & Okurut, T., 2001. The impact of alum discharges on a natural tropical wetland in Uganda. Water Res., Vol. 35, pp.795–807.
Okhoovat, M., Dadeny, P., & Eradat, S., 1994. A mechanistic description of Cd and Pb sorption on montmorillonite. J. Con. Hyd., Vol. 14, pp.57-63.
Kuvirel, J., Lagerkvist, A. & Maurice, C., 2008. Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments—a review. Waste Manage. Vol. 28 pp. 215–225.
Jala, S., & Goyal, D., 2005. Fly ash as a soil ameliorant for improving crop production—a review. Bioresour Technol ., Vol . 97, pp. 1136–47.
Brown, , Christensen, B., Lombi, E., McLaughlin, M., McGrath, S. & Colpaert, J., 2005. An interlaboratory study to test the ability of amendments to reduce the availability of Cd, Pb, and Zn in situ. Environ Pollut. Vol . 138, pp. 34–45.
Sharpley A. 2000. Agriculture and phosphorus management: the Chesapeake Bay. CRC.
Khare, N., Hesterberg, D. & Martin, JD., 2005. XANES investigation of phosphate sorption in single and binary systems of iron and aluminum oxide inerals. Environ Sci Technol. Vol. 39, pp. 2152–60.
McBride, MB., 1981. Chemisorption of Cd on calcite surfaces. SSSAJ, Vol. 44, 26-28.
Saha, JK., 2017. Soil Pollution - An Emerging Threat to Agriculture, Springer.
Panpatte, DG., 2019. Soil Fertility Management for Sustainable Development. Springer.
Yu J, Lei T, Shainberg I, Mamedov A, Levy G. Infiltration and erosion in soils treated with dry PAM and gypsum. Soil Sci Soc Am J 2003;67:630–6.
Zachara, J., 1992. Cadmium sorption to soil separates, SSSA, 56:1074-1084.
Havlin, JL., 2017. Soil fertility and fertilizers. Pearson India Education Services.
Intelligent Soil Management for Sustainable Agriculture. 2019. Calicut, Kerala, India.
Whalen J. Calcium co-amendments modify extractable orthophosphate levels in fresh and composted cattle manure. Water Air Soil Pollut 2002;141:105–24.
Arnich N, Lanhers MC, Laurensot F, Podor R, Montiel A, Burnel D. In vitro and in vivo studies of lead immobilization by synthetic hydroxyapatite. Environ Pollut 2003;124:139–49.
Hartley W, Edwards R, Lepp N. Arsenic and heavy metal mobility in iron oxideamended contaminated soils as evaluated by short- and long-term leaching tests. Environ Pollut 2004;131:495–504.
Dyer J, Trivedi P, Scrivner N, Sparks D. Surface complexation modeling of zinc sorption onto zeolite. J Colloid Interface Sci 2004;270:56–65.
Domek MJ, LeChevallier MW, Cameron SC, McFeters GA. Evidence for the role of copper in the injury process of coliform bacteria in drinking water. Appl Environ Microbiol 1984;48:289–93.
Pearson, HW., Mara, DD., & Bartone, CR., 1987. Guidelines for the minimum evaluation of the performance of full-scale wastes stabilization pond systems. Water Res., Vol. 21, pp. 1067–75.
Kaggwa, R., Mulalelo, C., Denny, P., & Okurut, , 2001. The impact of alum discharges on a natural tropical wetland in Uganda. Water Res. Vol. 35, pp.795–807.
Strawn, DG., Bohn, H., O Conner, GA., 2020. Soil Chemistry. Wiley publishers.
McCarty, LB. 2016. Applied Soil Physical Properties, Drainage, and Irrigation Strategies. Springer Cham Heidelberg New York Dordrecht London.
Smith, D., Moore, Jr., Griffis, C., Daniel, T., Edwards, D. & Boothe, D. 2001. Effects of alum and aluminum chloride on phosphorus runoff from swine manure. J Environ Qual; Vol. 30, pp. 992–8.
Rutherford, P., Dudas, M. & Samek, R., 1994. Environmental impacts of phosphogypsum. Sci Total , Vol. 149, pp.1-38.
McConchie, , Clark, MW. & Davies-McConchie F., 2002. New strategies for the management of bauxite refinery residues (red mud). Proceedings of the 6th International Alumina Quality Workshop. Australia: Brisbane;. pp. 8-13.