Scientific Research Journal (SCIRJ), Volume VII, Issue VI, June 2019 15
ISSN 2201-2796
www.scirj.org
© 2019, Scientific Research Journal
http://dx.doi.org/10.31364/SCIRJ/v7.i6.2019.P0619659
Heavy Metal Geochemistry of Soils in Selected
Industrial and Farmlands of Enugu State: A Preliminary
Investigation
Iyi Emmanuel Chibuike, Ozoko Daniel Chukwuemeka & Ezeh Christopher Chukwudi
Department of Geology and Mining
Faculty of Applied Natural Science
Enugu State University of Science and Technology, Enugu, Enugu State, Nigeria
Email: iyiemmanuel@yahoo.com
DOI: 10.31364/SCIRJ/v7.i6.2019.P0619659
http://dx.doi.org/10.31364/SCIRJ/v7.i6.2019.P0619659
Abstract: The present research was designed for the investigation of heavy metal geochemistry of soils in selected industrial and
farmlands of Enugu State. Soil samples were randomly collected at depths of 0.5m from 60 sites at dumpsites, industries, wetlands,
mechanic workshops, roadsides, animal dungs and river beds during wet and dry seasons using soil auger and polythene bags. The
soil samples were analyzed for Fe
3+
, Mn, As, Pb, Zn, Cd, Cr, Ni and Cu using standard analytical methods. The results show mean
value of Fe
3+
ranging from 515.62 to 107.8 mg/kg in the wet season and 578.7 to 107.8mg/kg during the dry season. Mn varies
between 83.5 - 18.05 mg/kg in the wet season and 101.9 - 18.1 mg/kg in the dry season. As range from 48.35 - 20.9 mg/kg during the
wet season as well as 46.97 - 25.25 mg/kg during the dry season. Mean levels of Pb ranged from 106.6 to 51.3 mg/kg in the wet
season and 96.1 to 43.8 mg/kg in the dry season. Zn concentration in the wet season varied between 425.05 and 228.95 mg/kg, and is
slightly lower than the dry season (432.2 and 190.0 mg/kg), while Cd was found in trace amounts between 2.013 to 0.422 mg/kg in
the wet season and is marginally higher than dry season (2.002 to 0.422 mg/kg). The mean values of Fe
3+
, Mn, As and Pb for both wet
and dry seasons in the study area have reached pollutant level based on FAO/WHO standards for industrial and agricultural soils.
Furthermore, Pearson correlation matrix of the parameters show high positive correlation between Mn and Fe; Zn and Fe; Zn and Mn;
Cu and Cd; as well as Cu and Cr for both seasons which indicates the strong relation between these variables and pointed out that
soils’ deterioration was associated with industrial and agricultural activities. However, there is a potential risk of poisoning of
humans, animals and agricultural produce by heavy metals in the study area.
Key words: Heavy Metal, Contamination, Enugu State, Industrial, Soil
I. INTRODUCTION
Soils are the end point for heavy metals generated by anthropogenic factors (e.g., metal finishing, paint pigment, livestock
wastewater, battery manufacturing, leather tanning, mining activities, municipal waste water sludges, urban composts, pesticides,
phosphate fertilizers, vehicular exhaust, energy and fuel production, power transmission, automobile mechanic workshops, chemical
lumps from industries and factories) and geogenic factors; including parent materials, the chemical and physical soil properties, metal
speciation and climatic conditions (Elanzer et al., 2015; Nouri and Haddioui 2016). Soils, especially those found within agricultural
and industrial sites are highly contaminated by heavy metals, including arsenic (As), iron (Fe
3+
), manganese (Mn) cadmium (Cd),
chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn). Human exposure to these metals can cause deadlier diseases like
gastrointestinal, neurological, tumor, head stuffiness, muscular, congestion of nasal mucous membranes and pharynx, edema of
eyelids, genetic and reproductive malfunctions (Zhao et al., 2012). Heavy metal soil contaminations have become a serious threat to
the health of humans, animals and plants (Ahmadipour et al., 2014).
The rapid increase in urbanization, industrialization and ever-growing population nationwide in combination with the effects of
increasing domestic, agricultural, municipal and industrial wastes has been reported by different authors as prior pollutant which pose
a grievous threat to the environment (Kelly et al., 1996; Assah et al., 2003; Adewara and Akinolu 2007; Njoku and Onyeka 2007;
Sharma et al., 2007; Osakwe 2010; Ekere and Ukoha, 2013). They also remarked that developing countries suffer from problems
arising from industrial effluent and agricultural discharge into soils. Ottensen and Langedal (2001), worked on the chemical
composition of urban surface soil in Trondheim, Noway, to determine whether stack emission from industrial sites, incinerators and
crematoria, as well as road traffic have caused local elevated concentrations of certain elements. They reported that, Cd, Hg, Pb, and
Zn have contaminated the surface soils in the central and older parts of the city and along main roads. The most dominant sources