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. 2019 May 20;9(22):190601.
doi: 10.5696/2156-9614-9.22.190601. eCollection 2019 Jun.

Spatial Distribution and Health Risk Assessment of Soil Pollution by Heavy Metals in Ijebu-Ode, Nigeria

Oludare Hakeem Adedeji  1 , Oluwafunmilayo O Olayinka  1 , Opeyemi O Tope-Ajayi  1
Affiliations

Spatial Distribution and Health Risk Assessment of Soil Pollution by Heavy Metals in Ijebu-Ode, Nigeria

Oludare Hakeem Adedeji et al. J Health Pollut. .

Abstract

Background: Soil pollution by heavy metals in urban areas is of major concern to city planners and policy makers because of the potential threat to human health. Hence, an investigation of soil pollution is crucial to urban environmental assessment and management.

Objective: To determine the spatial distribution and health risk assessment of seven heavy metals (cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn)) around Ijebu-ode, southwest Nigeria.

Methods: Surface soil samples were analyzed for Cd, Cr, Cu, Mn, Ni, Pb, and Zn levels using standard procedures. Geographic information system (GIS) data, pollution indices (enrichment factor, geo-accumulation index), and the health risk assessment model, respectively, were used to analyze the spatial distribution, pollution level, and potential health risk of heavy metals.

Results: Low pH was observed in the urban soils. The average concentrations of the seven heavy metals investigated were in order of Zn > Pb > Mn > Cu > Cd > Ni > Cr. There was high spatial variation in the distribution patterns of the heavy metals. The cancer risks for Cu, Mn, Pb, and Zn for children (1.50 × 10-3 - 2.71 × 10-2) and Mn, Pb, and Zn for adults (7.89 × 10-4 - 2.97 × 10-3) were higher than the acceptable range of 1 × 10-6 - 1 × 10-4.

Conclusions: Anthropogenic activities from different urban land uses contribute to the pollution levels and spatial distribution of heavy metals in soils. Increasing pollution of urban soil may contribute to the occurrence of some health risk for residents in the study area.

Competing interests: The authors declare no competing financial interests.

Keywords: GIS; geographic information system; health risk; heavy metal; toxicity; urban soils.

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Figures

Figure 1
Figure 1
Map of study area showing sampling locations
Figure 2
Figure 2
Percentage contributions of heavy metals across different land uses in the study area.
Figure 3
Figure 3
Percentage of non-carcinogenic risk distribution of different exposure pathways for adults and children in Ijebu-ode
Figure 4
Figure 4
Percentage contributions of heavy metals to different exposure pathways
See this image and copyright information in PMC

References

    1. Roche MY, Lechtenbohmer S, Fischedick M, Grone MC, Xia C, Dienst C. Concepts and methodologies for measuring the sustainability of cities. Annu Rev Environ Resour [Internet] 2014;39:519–47. doi: 10.1146/annurev-environ-012913-101223. [cited 2019 Mar 17] Available from: Subscription required to view. - DOI
    1. Yang L, Li Y, Peng K, Wu S. Nutrients and heavy metals in urban soils under different green space types in Anji, China. Catena [Internet] 2014 Apr;115:39–46. doi: 10.1016/j.catena.2013.11.008. [cited 2019 Mar 17] Available from: Subscription required to view. - DOI
    1. Kuzmanoski MM, Todorovic MN, Anicic Urosevic MP, Rajsic SF. Heavy metal content of soil in urban parks of Belgrade. Hemijska Industrija. 2014;68(5):643–51.
    1. Nezhad MT, Tabtabaii SM, Gholami A. Geochemical assessment of steel smelter-impacted urban soils, Ahvaz, Iran. J Geochem Explor [Internet] 2015 May;152:91–109. doi: 10.1016/j.gexplo.2015.02.005. [cited 2019 Mar 17] Available from: Subscription required to view. - DOI
    1. Li ZG, Zhang GS, Liu Y, Wan KY, Zhang RH, Chen F. Soil nutrient assessment for urban ecosystems in Hubei, China. PLoS One [Internet] 2013 Sep 27;8(9):e75856. doi: 10.1371/journal.pone.0075856. [cited 2019 Mar 17] Available from: - DOI - PMC - PubMed

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