Hematotoxic Effect of Consuming Geophagic Clay Contaminated with Heavy Metals: An Experimental Study in Wistar Rats (Rattus norvegicus)
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Geophagy, or the intentional ingestion of clay, is widely practiced in sub-Saharan Africa, particularly among pregnant women. However, its toxicological effects remain poorly documented. Clays may contain heavy metals such as lead (Pb), cadmium (Cd), arsenic (As), and nickel (Ni), which may become bioavailable after ingestion and cause systemic and hematological effects. In this study, Wistar rats were exposed for eight weeks to various doses of contaminated clay, administered either through the diet or by gavage. Blood concentrations of heavy metals, hematological parameters (red and white blood cells, hemoglobin, platelets), and essential trace elements (iron, manganese, selenium) were analyzed. The results show a dose-dependent accumulation of heavy metals. High doses, particularly when administered via gavage, caused severe microcytic anemia, leukopenia, and thrombocytopenia, suggesting bone marrow damage and disruption of heme synthesis. At moderate doses, milder effects with compensatory mechanisms were observed. A disruption in trace element balance was also noted, with a decrease in iron and manganese and an increase in selenium. The correlations confirm a link between heavy metal exposure and hematological disorders. This study highlights a health risk
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