CHEMICAL, MINERALOGICAL AND MICROBIOLOGICAL CHARACTERIZATION OF SOME GEOPHAGIC CLAYS FROM THE DEMOCRATIC REPUBLIC OF THE CONGO: CBRN RISKS

Abstract

This study focuses on the chemical, mineralogical, and microbiological characterization of geophagic clays from Grand Bandundu, Kisangani, and Kongo-Central in the Democratic Republic of Congo (DRC), with the aim of distinguishing kaolinitic clays from illitic ones. Traditionally consumed by populations in Kinshasa, these clays were analyzed to assess their potential health effects. X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses revealed that the clays from Kongo-Central are primarily kaolinitic, containing quartz, whereas those from Bulungu and Kisangani are mostly illitic with low quartz content. This distinction highlights specific properties, such as potential nutritional benefits due to minerals like calcium, magnesium, and iron. However, the presence of toxic elements such as lead and arsenic poses significant health risks. At the microbiological level, while the analyses revealed no contamination by Escherichia coli or Pseudomonas aeruginosa, the samples do not meet WHO standards, indicating hygiene deficiencies.