Geophagic Clays from Cameroon: Provenance, Metal Contamination and Health Risk Assessment.

This study assessed the mineralogical and geochemical characteristics of geophagic clays sold in some markets in Cameroon to ascertain their provenance, contamination status and human health risk. To achieve this, 40 samples from 13 markets in Cameroon were purchased and analysed using X-ray diffractometry, X-ray fluorescence and laser ablation inductively coupled plasma mass spectrometry for their mineralogy and geochemistry, respectively. The geophagic clays were dominantly made up of kaolinite and quartz.

U-Pb ages of detrital zircons in Cretaceous-Paleogene/Neogene kaolins within Eastern Dahomey and Niger Delta Basins (Nigeria) as provenance indicators.

Detrital zircon grains within four (4) deposits including two (2) Cretaceous and two (2) Paleogene/Neogene kaolins in Nigeria were analysed using U-Pb LA-SFICP-MS to determine their provenance. The zircon textures were dominated by xenocrystic cores and oscillatory zoning in the Cretaceous and Paleogene/Neogene kaolins, respectively. The Th/U ratios obtained for the detrital zircon grains within the kaolins were predominantly within known values for rocks with magmatic origin.

Health Risk Evaluation of Trace Elements in Geophagic Kaolinitic Clays within Eastern Dahomey and Niger Delta Basins, Nigeria.

The deliberate consumption of earthly materials is a universally recognised habit with health benefits and risks to those that practice it. Thirteen (13) samples comprising of six (6) Cretaceous and seven (7) Paleogene/Neogene geophagic kaolinitic materials, respectively, were collected and analysed for trace element concentrations (V, Cr, Co, Ni, Zn, Pb, and Fe), and possible risk on consumers' health. The trace element compositions were obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and X-ray fluorescence spectrometry (XRF) analytical methods.