Umwelt- und analytische Toxikologie

Heavy Metals Distribution in Soil Profile Exposed to Leachate of Septic Tanks in a School Environment

Abstract

Solomon Iyobu-Oki*, Ndokiari Boisa, Joshua Konne and John Ugbomah

This study examined the physicochemical properties of soil exposed to leachate from septic tanks within the International Secondary School of the Rivers State University, Rivers State, Nigeria. Soil samples were collected in quadruplicates from depths 0.0 m (surf), 0.5 m (sub), 1.0 m (deepsub) and 1.5 m(Msub) for each 0.5 m, 1.0 m,1.5 m and 2.0 m horizontal distances away from all eight sides of two septic tanks yielding a total of 128 samples. The samples were analyzed using standard physicochemical and AAS techniques, and the obtained experimental outcomes subjected to standard statistical treatment. The results showed that the means of the levels of pH, PO4, and Zn followed the order, surf>sub>deepsub>Msub. Other properties such as EC (Electrical Conductivity), TKN (Total Khejdhal Nitrogen), Ni and Cu also had highest levels of concentration or counts at the surface depth but did not follow this trend. Mn showed the highest occurrences at the Msub depth. The mean Ni level for the site was above the FMEenv and WHO maximum permissible levels respectively.