International Journal of Environment, Agriculture and Biotechnology (IJEAB) Vol-2, Issue-3, May -Jun- 2017 http://dx.doi.org/10.22161/ijeab/2.3.25 ISSN: 2456-1878 Quantification of Heavy Metals using Contamination and Pollution Index in Selected Refuse Dumpsites in Owerri, Imo State Southeast Nigeria Onwudike, S. U1, Igbozurike, C. I2, Ihem, E. E1., Osisi F. A.1, Ukah, C. I1 1Department of Soil Science and Technology, Federal University of Technology Owerri, Imo State Nigeria 2Department of Soil Science and Environment, Imo State University Owerri, Nigeria Corresponding author: Dr. S. U. Onwudike, Department of Soil Science and Technology, Federal University of Technology Owerri, Imo State Nigeria. Running title: Contamination and pollution level of heavy metals at dumpsites. Abstract— Many sites in urban cities are used for resulted to generation of large agricultural and municipal dumping of domestic, industrial and municipal wastes wastes [1]. Most often, people deposit these wastes on or because of high human population density in the area. along the road sides, unapproved areas, open dumpsites in Most often, people use these dumpsites for growing of the markets or in water ways [2] and management of these crops without knowing the level of heavy metal wastes has been an environmental challenge to Nigerian contamination in soils of these areas. This study governmental [3]. Inappropriate disposal of these wastes evaluated the quantification and contamination level of causes environmental pollution and contamination of heavy metals in some refuse dumpsites in communities of underground and surface water bodies [4]. Research the State Nigeria. Three replicate soil samples were works have shown that heavy metals such as lead, collected from the dumpsites and at 20 m away from the cadmium, nickel, manganese and chromium amongst non - dumpsite which do not receive sewage water within others are responsible for certain diseases in man [5]. the root zone of 0 – 40 cm depth using soil auger Large quantities of these toxic metals accumulate in soils sampler. Samples were analysed for soil properties and used as dumpsites [6]. Accumulation of these metals in heavy metal concentrations using standard methods. The the soil affect soil ecosystem thereby causing significant concentrations of the studied heavy metals (Cu, Pb, Zn loses of soil quality [7]. and Cd) were compared with the permissible limits of A lot of research has been conducted to evaluate the other countries. Results showed that in the three studied heavy metal concentrations in soils at refuse dumpsites locations, soil pH at dumpsites were 40 .6%, 39.4% and [8]. [9] studied the vertical migration of heavy metals in 38.9% higher than the values in the control sites while dumpsites soil in Maiduguri Metropolis Nigeria, [10] soil organic carbon were higher in the dumpsites by evaluated the concentrations of heavy metals in municipal 50.1%, 31.3% and 41.1% as compared to the control dumpsite soil and plants at Oke-ogi, Iree, Nigeria. These sites. Cu concentrations at the three locations were below authors found out different concentrations of heavy the standard limits of United Kingdom, European Union metals in dumpsites with some heavy metals being above (EU), USA and WHO. The concentrations of the studied the permissible limit. Soil acts as a major sink and source heavy metals passed the contamination stage and of heavy metal ions [7]. Consumption of foods produced therefore will pose negative effect on plant and soil from dumpsites help in heavy metal accumulation in the environment. Use of the dumpsite for crop cultivation or body which is detrimental to life. This problem is as compost materials should be avoided and construction common among farmers who make use of soils from of shallow wells near these areas should be discouraged. dumpsites as manure or as soil amendments for the Keywords— Contamination, environment, heavy metal, production of vegetable and other arable crops. municipal wastes, pollution. According to [11], contamination / pollution index is a method of comparing the concentration of soil heavy I. INTRODUCTION metals with an international standard to determine the Migration of people from rural to urban cities has degree of pollution or contamination of a given location increased human population density and hence has and the effect of the concentration on soil plant and www.ijeab.com Page | 1202 International Journal of Environment, Agriculture and Biotechnology (IJEAB) Vol-2, Issue-3, May -Jun- 2017 http://dx.doi.org/10.22161/ijeab/2.3.25 ISSN: 2456-1878 environment. Differences between soil contamination heavy metals using contamination and pollution index in range and soil pollution range is given by the metal selected refuse dumpsites in Owerri, Imo State Southeast contamination/pollution index (MPI) [11]. This index Nigeria. represents the ratio between the heavy metal content effectively measured in soil by chemical analysis and II. MATERIALS AND METHODS reference value obtained from the control soil [12]. 2.1. The study area Heavy metal concentration at dumpsites often exceeds the The study was carried out in Owerri (Imo State Capital) permissible limits and could be detrimental to land users. Nigeria. Three communities were studied namely [11] Suggested periodic evaluation of the concentration of Ihiagwa, Umuchima and Eziobodo communities. The heavy metal or toxic substances at dumpsites for policy sampling sites in these communities were selected based making. There is a dearth of information on the on human activities around each dumpsite. The sites’ quantification of heavy metals using contamination and coordinates were taken with a Geographical Positioning pollution index in selected refuse dumpsites in the study System (GPS) as shown in Table 1. area. The study therefore evaluated the quantification of Table.1: Coordinates of the study locations Location Land use Longitude Latitude Ihiagwa1 Refuse dumpsite 5˚ 24ˈ 11ˈˈN 7˚ 01ˈ 22ˈˈE Umuchima 1 Refuse dumpsite 5˚ 23ˈ 35ˈˈN 6˚ 01ˈ 26ˈˈE Eziobodo 1 Refuse dumpsite 5˚ 22ˈ 48ˈˈN 7˚ 01ˈ 36ˈˈE Ihiagwa2 Refuse dumpsite 5˚ 24ˈ 16ˈˈN 7˚ 02ˈ 26ˈˈE Umuchima 2 Refuse dumpsite 5˚ 23ˈ 31ˈˈN 7˚ 01ˈ 21ˈˈE Eziobodo 2 Refuse dumpsite 5˚ 23ˈ 05ˈˈN 6˚ 01ˈ 43ˈˈE Ihiagwa 3 Refuse dumpsite 5˚ 24ˈ 07ˈˈN 7˚ 01ˈ 23ˈˈE Umuchima 3 Refuse dumpsite 5˚ 24ˈ 12ˈˈN 7˚ 03ˈ 22ˈˈE Eziobodo 3 Refuse dumpsite 5˚ 22ˈ 45ˈˈN 6˚ 01ˈ 31ˈˈE The locations have an average annual rainfall range of 2.3. Laboratory Analysis 1950 mm – 2000 mm and annual temperature range of Particle size distribution (sand, silt and clay fractions) was 27°C – 30°C with average relative humidity of 79%. The determined by hydrometer method according to the geological material of soil in the study area is an ultisol procedure of [15]. Soil pH was determined using pH and classified as Typic Haplustult [13], derived from metre in soil / liquid suspension of 1: 2.5 according to Coastal Plain Sands (Benin formation) of the Oligocene- [16]. Organic carbon was determined using chromic acid Miocene geological era and are characterized by low wet oxidation method according to [17]. Total nitrogen organic matter, cation exchange capacity and are highly was determined by kjeldahl digestion method using leached [14]. concentrated H2S04 and sodium copper sulphate catalyst 2.2. Soil sampling mixture according to [18]. Available phosphorus was A reconnaissance visit of the study area was carried out to determined according to [19]. Exchangeable Mg and Ca demarcate the sampling points in the three communities were extracted using ethylene diamine tetra acetic acid under refuse dumpsite practices and a control soil 20 m (EDTA) [20] while exchangeable K and Na were away which do not receive sewage water. At each extracted using 1 N Neutral ammonium acetate sampling site, three replicate samples of approximately (NH4OAC) and then read using flame photometer [20]. 1kg of soil were randomly collected in each community Total exchangeable base (TEB) was obtained by the from a mini pedon of 0 – 40 cm depth using soil sampling summation of exchangeable Ca, Mg, K and Na. spiral auger sampler. The samples were mixed thoroughly 2.4. Determination of heavy metal and taken in labelled nylon bags to differentiate the Heavy metals were determined by weighing 10 g of each sampling points. The samples were grounded, air dried soil sample into a 100 mL conical flask washed with and sieved through 2mm mesh sieve and taken to the deionized water. In each flask, 6 mL HNO3/HClO4 acid in laboratory for heavy metal content and routine soil the ratio 2:1 is added and left overnight. Each sample was analysis. digested at 150°C for about 90 minutes and the www.ijeab.com Page | 1203 International Journal of Environment, Agriculture and Biotechnology (IJEAB) Vol-2, Issue-3, May -Jun- 2017 http://dx.doi.org/10.22161/ijeab/2.3.25 ISSN: 2456-1878 temperature was increased to 230°C for 30 minutes. HCl Rs = concentration of heavy metal in solution was added in ratio 1:1 to the digested sample and reference soil (control) re-digested again for another 30 minutes. The digested The difference between soil contamination range and soil sample was then washed into 100 mL volumetric flask. pollution range is given by the metal The mixture was cooled down to room temperature to contamination/pollution index (MPI). The value of this avoid formation of insoluble perchloric compounds and index represents the ratio between the heavy metal late made up to mark with deionized water. Atomic content effectively measured in soil by chemical analysis absorption spectrometer is used to read the heavy metal and reference value obtained from the control soil. Values concentration in the digest and the amount of each heavy of contamination/pollution index of soil greater than 1 (> metal was extrapolated from the calibration graph 1), define the pollution range and those less than 1 (<1) prepared.