title: Ecological Risk of Heavy Metals and a Metalloid in Agricultural Soils in Tarkwa, Ghana.
abstract: Heavy metals and a metalloid in agricultural soils in 19 communities in Tarkwa were analyzed to assess the potential ecological risk. A total of 147 soil samples were collected in June, 2012 and analyzed for As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn. Mean concentrations (mg/kg dw) of heavy metals in the communities decreased in order of Zn (39) ˃ Cr (21) ˃ Pb (7.2) ˃ Cu (6.2) ˃ As (4.4) ˃ Ni (3.7) ˃ Co (1.8) ˃ Hg (0.32) ˃ Cd (0.050). Correlations among heavy metals and soil properties indicated that soil organic matter could have substantial influence on the total contents of these metals in soil. From the results, integrated pollution (C(deg)) in some communities such as, Wangarakrom (11), Badukrom (13) and T-Tamso (17) indicated high pollution with toxic metals, especially from As and Hg. Potential ecological risk (RI) indices indicated low (Mile 7) to high risks (Wangarakrom; Badukrom) of metals. Based on pollution coefficient (C(i)(f)), C(deg), monomial ecological risk (E(i)(r)) and RI, the investigated soils fall within low to high contamination and risk of heavy metals to the ecological system especially plants, soil invertebrates and/or mammalian wildlife. This represented moderate potential ecological risk in the study area, and mining activities have played a significant role.
authors.affiliation: Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita ku, Sapporo 060-0818, Japan. borteysam@yahoo.com.
authors.forename: Nesta
authors.initials: N
authors.lastname: Bortey-Sam
authors.affiliation: Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita ku, Sapporo 060-0818, Japan. shouta-nakayama@vetmed.hokudai.ac.jp.
authors.forename: Shouta M M
authors.initials: SM
authors.lastname: Nakayama
authors.affiliation: Department of Chemistry, Kwame Nkrumah University of Science and Technology, Private Mail Bag, KNUST, Kumasi, Ghana. wofakmann@yahoo.com.
authors.forename: Osei
authors.initials: O
authors.lastname: Akoto
authors.affiliation: Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita ku, Sapporo 060-0818, Japan. y_ikenaka@vetmed.hokudai.ac.jp.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ikenaka
authors.affiliation: Department of Chemistry, Kwame Nkrumah University of Science and Technology, Private Mail Bag, KNUST, Kumasi, Ghana. elvixbaid@yahoo.com.
authors.forename: Elvis
authors.initials: E
authors.lastname: Baidoo
authors.affiliation: Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita ku, Sapporo 060-0818, Japan. hazuki.mizukawa@vetmed.hokudai.ac.jp.
authors.forename: Hazuki
authors.initials: H
authors.lastname: Mizukawa
authors.affiliation: Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita ku, Sapporo 060-0818, Japan. ishizum@vetmed.hokudai.ac.jp.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Ishizuka
mesh_terms: D000383:Agriculture; D004463:Ecology; D004784:Environmental Monitoring; D005869:Ghana; D058955:Metalloids / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis*; D008906:Mining; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D058955:Metalloids; D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants
keywords: Tarkwa; agricultural soil; ecological risk; heavy metals; integrated pollution; metalloid