Remediation of a Mercury-Contaminated Industrial Soil Using Bioavailable Contaminant Stripping

• Published in: Pedosphere Vol. 23; no. 1; pp. 104 - 110
• Main Authors: PEDRON, F., PETRUZZELLI, G., BARBAFIERI, M., TASSI, E.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2013; National Research Council, Institute of Ecosystem Studies, Via Moruzzi 1, 56124 Pisa,Italy
• Subjects: Brassica juncea; heavy metal; Helianthus; mercury bioavailability; mobilizing agent; plant species; Poa annua; remediation approach; 修复; 剥离; 土壤; 工业污染; 汞污染; 污染物; 生物利用度; 生物群落; heavy metal; mobilizing agent; mercury bioavailability; plant species; remediation approach
• ISSN: 1002-0160; 2210-5107
• DOI: 10.1016/S1002-0160(12)60085-X

The method to remove bioavailable amounts of heavy metals from a contaminated soil by using plants is defined as bioavailable contaminant stripping （BCS） and could safely be applied if the soil＇s long-term ability to replenish the bioavuilable pool is known. The aim of this study was to evaluate the ability of three common plant species selected, Brassica juncea, Poa annua, and Helianthus annus, to remove bioavailable amounts of mercury （Hg） from a contaminated industrial soil containing 15.1 mg kg-1 Hg. Trials were carried out under greenhouse conditions using pots （mesocosms）. According to the precautionary principle, we modified the BCS remediation approach by adding a new step, in which mercury bioavailability was increased by the addition of a strong mobilizing agent, ammonium thiosulphate, （NH4）28203, to obtain an estimate of the likely long-term bioavailable Hg pool. The modified BCS remediation approach was called enhanced bioavailable contaminant stripping （EBCS）. After one growth cycle, nearly all the bioavailable mercury （95.7%） was removed and the metal remaining in the soil was considered inert since it was neither extractable by （NH4）2S2O3 nor taken up by plants during a second growth cycle. The results demonstrated that EBCS appeared promising since it removed the most dangerous metal forms while substantially shortening the cleanup time.