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Article

Assessing the Efficacy of the Artisan Relocation Policy as a Soil Pollution Mitigation Strategy in Urban Nigeria: Five Years after Relocation

Ibigoni Clinton Howard ORCID ,  Chima Hyacinth Nwafor-Nwangwu ORCID ,  Chioma Chinagorom Howard ORCID
    Received: 4 August 2025; Revised: 2 November 2025; Accepted: 9 November 2025; Published: 16 November 2025

    Abstract

    Government‑mandated relocation of artisan workshop operators in Nigeria aims to reduce soil pollution from mechanic clusters, yet its effectiveness as a remediation strategy has not been empirically evaluated. This study provides the first evidence‑based assessment of artisan relocation policy efficacy, using the Old Nekede mechanic village, Imo State, five years post‑relocation as a case study. Soil samples from five georeferenced stations were analysed for cobalt, nickel, iron, zinc, lead, and aluminium, and benchmarked against regulatory standards, geo‑accumulation indices, ecological risk index, and a policy effectiveness scorecard. Human health risk was as‑
    sessed using the United States Environmental Protection Agency (USEPA) four‑step framework across ingestion, dermal, and inhalation pathways for adult and child receptors. Source control was confirmed: Pb and Ni fell below detection limits at all stations. However, Fe, Zn, and Co persisted at mean topsoil concentrations of 843.2, 115.1, and 6.45 mg/kg, substantially exceeding regulatory target intervention values. Active Fe leaching into subsoil at Site D indicated continuing localised groundwater risk. Child hazard index (HI) ranged from 0.009 to 0.043 and did not exceed 1.0 at any station; adult HI ranged from 0.001 to 0.005. Cobalt carcinogenic risk is not quantified,
    as USEPA Integrated Risk Information System (IRIS) does not publish a verified oral cancer slope factor for cobalt; the non‑carcinogenic HI is used as the basis for cobalt risk characterisation in this study. The policy scorecard rated three of eight criteria as Achieved, two as Partial, and three as Not Achieved. Artisan relocation is an effective
    source‑control measure but is fundamentally insufficient as a complete soil pollution mitigation strategy. Future policy must incorporate mandatory remediation frameworks, structured post‑closure monitoring, and community health protection provisions.

    Keywords

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