Radiological and toxicological implications of geophagic kaolin consumption during pregnancy in Ghana: A screening-level assessment of maternal and Foetal Exposure

Geophagic consumption of kaolin during pregnancy is widely reported in Ghana, yet its radiological implications remain poorly characterised within the broader environmental exposure framework. This study evaluates the potential contribution of naturally occurring radionuclides in commercially available kaolin to maternal and foetal radiation dose, situating radiological exposure within the wider context of geophagia-related health risks. Ten bulk kaolin samples obtained from major markets in southern Ghana were analysed using high-resolution gamma spectrometry. Activity concentrations of radionuclides from the uranium-238 and thorium-232 decay series, as well as potassium-40, were quantified. Maternal and foetal committed effective doses were estimated under two ingestion scenarios representing low and high habitual consumption. All samples contained measurable radionuclides, with potassium-40 exhibiting the highest activity concentrations, while radium and thorium series radionuclides contributed most strongly to dose. Estimated foetal doses ranged from 0.013 to 0.047 mSv, whereas maternal doses ranged from 0.431 to 1.509 mSv. Although these doses fall within the range of low-level natural exposures, sustained high intake resulted in maternal doses approaching commonly referenced public exposure benchmarks. The findings identify geophagic kaolin as a previously under-recognised ingestion pathway for naturally occurring radionuclides in Ghana. While radiological exposure is unlikely to represent the dominant health risk compared with toxicological and microbiological hazards, it contributes to cumulative exposure and warrants inclusion in integrated environmental health assessments.