title: Variation and distribution of metals and metalloids in soil/ash mixtures from Agbogbloshie e-waste recycling site in Accra, Ghana.
abstract: Illegal import and improper recycling of electronic waste (e-waste) are an environmental issue in developing countries around the world. African countries are no exception to this problem and the Agbogbloshie market in Accra, Ghana is a well-known e-waste recycling site. We have studied the levels of metal(loid)s in the mixtures of residual ash, formed by the burning of e-waste, and the cover soil, obtained using a portable X-ray fluorescence spectrometer (P-XRF) coupled with determination of the 1M HCl-extractable fraction by an inductively coupled plasma mass spectrometer. The accuracy and precision of the P-XRF measurements were evaluated by measuring 18 standard reference materials; this indicated the acceptable but limited quality of this method as a screening tool. The HCl-extractable levels of Al, Co, Cu, Zn, Cd, In, Sb, Ba, and Pb in 10 soil/ash mixtures varied by more than one order of magnitude. The levels of these metal(loid)s were found to be correlated with the color (i.e., soil/ash ratio), suggesting that they are being released from disposed e-waste via open burning. The source of rare elements could be constrained using correlation to the predominant metals. Human hazard quotient values based on ingestion of soil/ash mixtures exceeded unity for Pb, As, Sb, and Cu in a high-exposure scenario. This study showed that along with common metals, rare metal(loid)s are also enriched in the e-waste burning site. We suggest that risk assessment considering exposure to multiple metal(loid)s should be addressed in studies of e-waste recycling sites.
authors.affiliation: Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan. Electronic address: itai@sci.ehime-u.ac.jp.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Itai
authors.affiliation: Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan.
authors.forename: Masanari
authors.initials: M
authors.lastname: Otsuka
authors.affiliation: Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan; CSIR Water Research Institute, P. O. Box AH 38, Achimota, Accra, Ghana.
authors.forename: Kwadwo Ansong
authors.initials: KA
authors.lastname: Asante
authors.affiliation: Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Muto
authors.affiliation: CSIR Water Research Institute, P. O. Box AH 38, Achimota, Accra, Ghana.
authors.forename: Yaw
authors.initials: Y
authors.lastname: Opoku-Ankomah
authors.affiliation: CSIR Water Research Institute, P. O. Box AH 38, Achimota, Accra, Ghana.
authors.forename: Osmund Duodu
authors.initials: OD
authors.lastname: Ansa-Asare
authors.affiliation: Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Tanabe
mesh_terms: D059029:Electronic Waste; D004784:Environmental Monitoring; D005869:Ghana; D058955:Metalloids / Q000032:analysis*; D008670:Metals / Q000032:analysis*; D059027:Recycling; D012989:Soil Pollutants / Q000032:analysis*; D018505:Waste Management
chemical_list: D058955:Metalloids; D008670:Metals; D012989:Soil Pollutants
keywords: E-waste; Ghana; Portable XRF; Risk assessment; Trace element