Heavy Metals Contamination in Soil and Their Risk Assessment and Bioremediation in Korea : Case Histories

1. Measurement of 1.0g soil sieved -80 mesh Making of 2L aqueous extraction fluid with DI water and 60.06g glycine 1 2 1 Adjustment to pH 1.5 by conc. HCl Putting of 1.0g soil and 100mL extraction fluid into wide-mouth HDPE bottle 4 3 5 Placing of the bottle into extractor of water bath maintained at 37 oC 6 6 7 Rotating of extractor at 30 rpm for 1 hour 7 Extraction of 10mL fluid from reaction vessel Heavy Metal Contamination in Soil Abstract Geological Map of the Chubu Area Mine As Cd Zn Dongil mine 5.76 2.56 0.80 Okdong mine 8.88 1.11 0.44 Songcheon mine 26.32 0.42 10.74 SBET (Simple Bioavailability Extraction Test) Dongjung mine 1.00 0.13 0.02 Dokok mine 0.11 3.45 0.03 Hwacheon mine 5.38 0.97 0.57 Mine Soil pathway Groundwater pathway Rice grain pathway Bacillus carboniphilus JCM9731 79 Bacillus sporothermodurans M215 45 Dongil mine 3.1 x 10-6 6.6 x 10-4 3.6 x 10-4 39 Bacillus shackletonii LMG 18435 Bacillus aeolius 41 Okdong mine 1.2 x 10-6 7.2 x 10-4 8.5 x 10-4 52 Bacillus marisflavi TF11 Songcheon mine 2.0 x 10-5 4.6 x 10-3 - Bacillus aquimaris TF12 85 Bacillus vietnamensis 151 95 Dongjung mine 8.0 x 10-6 1.7 x 10-4 - Bacillus muralis LMG 20238 54 Dokok mine 6.8 x 10-7 1.9 x 10-5 - Bacillus niacini IFO15566 Bacillus siralis 171544 62 Hwacheon mine 1.6 x 10-6 1.3 x 10-4 8.2 x 10-4 Bacillus flexus IFO15715 52 44 SPb-1 Bacillus thuringiensis NCIMB 9134 91 Bacillus thuringiensis ATCC10792 90 Bacillus weihenstephanensis DSM11821 100 Bacillus mycoides ATCC6462 96 Bacillus mycoides 6462 90 Bacillus halmapalus DSM 8723 Bacillus luciferensis LMG 18422 97 Heavy Metals Contamination in Soil and Their Risk Assessment and Bioremediation in Korea : Case Histories Hyo-Taek Chon*1) , Jin-Soo Lee2) , and Jong-Un Lee3) • Department of Energy Resources Engineering, Seoul National University, Seoul 151-744, Korea ( chon@snu.ac.kr) • Technology Research Center, Mine Reclamation Corporation, Seoul 110-727, Korea • Department of Energy and Resources Engineering, Chonnam National University, Gwangju 500-757, Korea In this paper some case histories on heavy metals contamination in soil, human risk assessment around metal mine areas, and bioremediation of heavy metals-contaminated sites are reviewed. Heavy metal contamination in soil is classified into two categories; one is natural enrichment of heavy metals in soil from high background source rocks, and the other is anthropogenic contamination from non-point and point sources. Some potentially toxic elements are highly enriched in areas covered with black shale. The level and dispersion patterns of Se and U in soil underlain by black shale were discussed in regional and local scales. Heavy metals contamination in the areas of abandoned base metal mines was investigated. The concept of pollution index (PI) of soils gives important information on the extent and degree of multi-element contamination and can be applied to the evaluation of soils before their agricultural use and remediation. Pollution level of Pt in dusts and soils from various traffic volume urban roads in and around Seoul, capital city of Korea, waspresented. Environmental geochemical surveys were undertaken around some abandoned metal mine sites to investigate the bioavailability of As and heavy metals by the SBET (simple bioavailability extraction test) method and to assess the risk of adverse health effects on human exposure to heavy metals influenced by previous mining activities. One case history on biosorption of cation heavy metals to microbial cells is introduced to present its potential for the bioremediation of contaminated field site. Natural Enrichment (The Occurrence and Dispersion of Potentially Toxic Elements in Areas Covered with Black Shales) Se and U Concentrations in Soils in Dukpyung Area - Local Scale - Regional Scale Heavy metal concentration in soils Geological Map of Dukpyung Area Study Area Enrichment Index (EI) Map Dukpyung Se Chubu Se and U Concentrations in Soils in Chubu Area Guryongsan (north) and Changri (south) Black Shale Formation EI = Se U Anthropogenic Soil Contamination 1) Heavy Metals Contamination around Metal Mine Sites 2) Pollution Level of Platinum in Urban Environment Pt levels in road dusts PI (Pollution Index) Seoul metropolitan city in Korea • The capital city of Korea • The total area : 605.52km² • Population : 10,456,095 as of the 1/4 of 2008 • 2.95 million vehicles were on register in 2008 • Mean traffic volume : 4.6 million vehicles/day in 2004 PI > 1 : metal concentrations in soil are above the tolerable level PI < 1 : average level of metals in soil is below the tolerable level PI = Heavy metal concentrations around the Sambo Pb-Zn barite mine Soil Sampling locations around the Sambo Pb-Zn barite mine Pollution index in soils around the Sambo Pb-Zn barite mine Pt level vs. Traffic Volume There is a tendency to increase Pt levels in road dusts along with traffic volume Highest level(Busy road in Seoul) Lowest level(Suburbs of Seoul) Hazard indices of As, Cd and Zn for toxic (non-cancer) risk Human Risk Assessment around Abandoned MetalMine Sites Multiple Pathways of Exposure Abandoned Metal Mine Sites 1. Aqueous effluents entering surface and groundwater systems 2. Contaminated dust entering surface water bodies 3. Contaminated surface and groundwater used for irrigation and drinking 4. Disposal of contaminated articulate matter onto agricultural soils 5. Soil ingestion (through bad hygiene) 6. Plant uptake from soils 7. Ingestion of contaminated plants Results of cancer risk for As with exposure pathway Bioremediation Identification of the Isolated Bacterium from Contaminated Soil Experimental Procedure of Biosorption Biosorption Effects of Pb and Cd by SPb-1 According to the Initial Concentrations of the Heavy Metals Isolation of bacteria from oil-contaminated soil Adaptation of isolated bacteria to Pb and incubation Mixing of Pb solution and cells in various condition Separation of biomass by centrifugation Analysis of residual Pb and Cd concentrations by AAS Pb Cd