POTENTIAL ECOLOGICAL RISK OF HEAVY METAL DISTRIBUTION IN CEMETERY SOILS

Abstract

IN THIS PAPER, PRELIMINARY INVESTIGATION WAS CONDUCTED TO EVALUATE THE POTENTIAL ECOLOGICAL RISK OF HEAVY METALS CONTAMINATION IN CEMETERY SOILS. NECROSOL SAMPLES WERE COLLECTED FROM WITHIN AND AROUND THE VICINITY OF THE LARGEST MASS GRAVE IN RWANDA AND ANALYZED FOR HEAVY METAL CONCENTRATIONS USING TOTAL DIGESTION–INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS. BASED ON THE CONCENTRATIONS OF AS, CU, CR, PB, AND ZN, THE OVERALL CONTAMINATION DEGREE (CDEG) AND POTENTIAL ECOLOGICAL RISKS STATUS (RI) OF THE NECROSOLS WERE DETERMINED. THE PRELIMINARY RESULTS REVEALED THAT THE ASSOCIATED CEMETERY SOILS ARE ONLY CONTAMINATED TO A LOW DEGREE. ON THE OTHER HAND, ASSESSMENT OF THE POTENTIAL ECOLOGICAL RISK INDEX (RI) REVEALED THAT CUMULATIVE HEAVY METAL CONTENT OF THE SOIL DO NOT POSE ANY SIGNIFICANT ECOLOGICAL RISKS. THESE FINDINGS, THEREFORE, SUGGEST THAT, WHILE CEMETERY SOILS MAY BE TOXIC DUE TO THE ACCUMULATION OF CERTAIN HEAVY METALS, THEIR OVERALL ECOLOGICAL RISKS MAY BE MINIMAL AND INSIGNIFICANT.