ANALYSIS OF THE LEVELS OF SELECTED HEAVY METALS IN THE VICINITY OF A LEAD BATTERIES RECYCLER PLANT IN ATHI-RIVER, KENYA

Abstract

The levels of heavy metals in the environment have been increasing in the recent past as a result of human activities. Since toxicity of heavy metals is widely known, their speciation is increasingly attracting attention. There is therefore need to determine the extent of contamination, in particular those of toxic heavy metals. This study thus aimed to ascertain the levels of heavy metals in soils around a lead battery smelting plant in Athi River, Kenya. A total of thirty-six (36) soil samples were collected randomly from six sampling sites around the plant. Sampling was conducted three times both in dry and wet seasons. The concentrations heavy metals (Zn, Cd, Cr, Ni, Pb and Cu) were determined using the Atomic Absorption Spectrophotometer machine (AAS). The results showed that the average concentration of Pb for the dry season was 3918.5 ppm and wet season was 3706 ppm. For Zn, the mean concentration was 111.83 ppm for dry and 90.83 ppm for wet season. For Cd, the average concentration for the dry season was 13.52 ppm and wet season was 9.63 ppm. For Cr, the mean concentration was 186.67 ppm for dry and 147.17 ppm for wet season. For Cu, the mean concentration was 0.9 ppm for dry and 0.4 ppm for wet season. Finally, the mean concentration of Ni was 23.25 ppm for dry and 22.15 ppm for wet season. The concentrations of Pb, Cr and Cd which were higher than the set limits by USEPA while those of Zn, Cu and Ni were below the set limits. The t-test results showed that the concentrations of all the metals were significantly different for the dry and wet seasons. Additionally, the results showed that the soils were acidic with pH values ranging from 3.85 – 5.00. In order to safeguard the health of the residents of this area, the study recommends that the government through the National Environmental Management Authority (NEMA) should deal with solid waste disposal at the smelting plant by imposing strict measures.