1. Department of Chemistry, Delta State University, P.M.B. 1, Abraka, Delta State, Nigeria
2. Department of Geology, Delta State University, P.M.B 1, Abraka, Delta State, Nigeria
3. Environment Department, Nigerian Agip Oil Company, Port Harcourt, Rivers State, Nigeria
4. School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Durban, South Africa