Accumulation of heavy metals occurrence in industrial soils of Gebeng industrial area / Nur Izzati Mahamad Zamal Shari

The aim of this study was to measure the deposited concentration of Ni, Fe, Mn and Zn in the surface soil around Gebeng Industrial Area (GIA), Kuantan, Pahang. Eight samples were collected from four different directions: north, south, east and west of GIA during the monsoon season from December 2012 to January 2013. All the soils were digested by using aqua regia and the metals concentration in soils were analysed by using Flame Atomic Absorption Spectrometer (FAAS). The mean concentrations of heavy metals in soils obtained were: Zn has the value of 41.4 mg/kg, 13.4 mg/kg for Ni, 69.2 mg/kg for Mn and 39,685.4 mg/kg for Fe and were ranked as follow: Fe > Mn > Zn > Ni. Two different parameters were used to describe the contamination of these metals in the soil: Contamination Factor (CF) and Enrichment Factor (EF). Based on the four directions for CF, it is suggested that mostly the soils in these areas were in the categories of no or suspected contamination and none of the area has the extreme contamination level of heavy metals in the soil. A factor that leads to the differences CF values among these sites is the type of soil that act as recipient of heavy metals pollutants. From the values of EF, these elements can be grouped into two potential sources which are
anthropogenic (EF>10) and natural sources (EF<10). The results obtained showed that only 12.5% from all the data from anthropogenic sources and the remaining are came from natural or lithogenic sources. The pattern that was observed in this study is the higher EF value of the elements was recorded as the distance of the sampling point further away from central point. This pattern probably means that the heavy metals distribution throughout the region is generally influenced by the climate conditions - prevailing wind and rainfall. Based on the overall results obtained, it is clearly showed that most of the soils were contaminated by the industrial activities at GIA due to the higher values as compared to the background value.