title: Immobilizer-assisted management of metal-contaminated agricultural soils for safer food production.
abstract: Production of food crops on metal contaminated agricultural soils is of concern because consumers are potentially exposed to hazardous metals via dietary intake of such crops or crop derived products. Therefore, the current study was conducted to develop management protocols for crop cultivation to allow safer food production. Metal uptake, as influenced by pH change-induced immobilizing agents (dolomite, steel slag, and agricultural lime) and sorption agents (zeolite and compost), was monitored in three common plants representative of leafy (Chinese cabbage), root (spring onion) and fruit (red pepper) vegetables, in a field experiment. The efficiency of the immobilizing agents was assessed by their ability to decrease the phytoavailability of metals (Cd, Pb, and Zn). The fruit vegetable (red pepper) showed the least accumulation of Cd (0.16-0.29 mgkg(-1) DW) and Pb (0.2-0.9 mgkg(-1) DW) in edible parts regardless of treatment, indicating selection of low metal accumulating crops was a reasonable strategy for safer food production. However, safer food production was more likely to be achievable by combining crop selection with immobilizing agent amendment of soils. Among the immobilizing agents, pH change-induced immobilizers were more effective than sorption agents, showing decreases in Cd and Pb concentrations in each plant well below standard limits. The efficiency of pH change-induced immobilizers was also comparable to reductions obtained by 'clean soil cover' where the total metal concentrations of the plow layer was reduced via capping the surface with uncontaminated soil, implying that pH change-induced immobilizers can be practically applied to metal contaminated agricultural soils for safer food production.
authors.affiliation: Division of Environmental Science & Ecological Engineering, College of Life and Environmental Sciences, Korea University, Seoul, Republic of Korea. kkr419@hanmail.net
authors.forename: Kwon-Rae
authors.initials: KR
authors.lastname: Kim
authors.forename: Jeong-Gyu
authors.initials: JG
authors.lastname: Kim
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Park
authors.forename: Min-Suk
authors.initials: MS
authors.lastname: Kim
authors.forename: Gary
authors.initials: G
authors.lastname: Owens
authors.forename: Gyu-Hoon
authors.initials: GH
authors.lastname: Youn
authors.forename: Jin-Su
authors.initials: JS
authors.lastname: Lee
mesh_terms: D002119:Calcium Carbonate / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry; D004784:Environmental Monitoring; D059022:Food Safety; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D010087:Oxides / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D014675:Vegetables / Q000378:metabolism*; D017641:Zeolites / Q000737:chemistry
chemical_list: D017610:Calcium Compounds; D019216:Metals, Heavy; D010087:Oxides; D012987:Soil; D012989:Soil Pollutants; D017641:Zeolites; C016538:lime; D002119:Calcium Carbonate; D008274:Magnesium; C028042:calcium magnesium carbonate