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Review of the nature of some geophagic materials and their potential health effects on pregnant women: some examples from Africa

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Abstract

The voluntary human consumption of soil known as geophagy is a global practice and deep-rooted in many African cultures. The nature of geophagic material varies widely from the types to the composition. Generally, clay and termite mound soils are the main materials consumed by geophagists. Several studies revealed that gestating women across the world consume more soil than other groups for numerous motives. These motivations are related to medicinal, cultural and nutrients supplementation. Although geophagy in pregnancy (GiP) is a universal dynamic habit, the highest prevalence has been reported in African countries such as Kenya, Ghana, Rwanda, Nigeria, Tanzania, and South Africa. Geophagy can be both beneficial and detrimental. Its health effects depend on the amount and composition of the ingested soils, which is subjective to the geology and soil formation processes. In most cases, the negative health effects concomitant with the practice of geophagy eclipse the positive effects. Therefore, knowledge about the nature of geophagic material and the health effects that might arise from their consumption is important.

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Acknowledgements

The authors are grateful to the University of Johannesburg and the National Research Foundation (NRF, South Africa) Incentive Funding for Rated Researchers (Grant No 91059) and Collaborative Postgraduate training programme (Grant No. 105295) for the financial support. Carla Candeias is thankful to the Portuguese Institutions University of Aveiro, IU GeoBioTec and to FCT (UID/GEO/04035/2013 and SFRH/BPD/99636/2014) for financial support of her work. Dr Langenhoven, Delicia, Department of English, University of Johannesburg, South Africa, is thanked for the language correction of the early version of the manuscript. Anonymous reviewers and the editor of the journal are acknowledged for their valuable comments, which helped to improve the manuscript.

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Authors and Affiliations

  1. Department of Geology, University of Johannesburg, Johannesburg, South Africa

    Selma N. Kambunga & Hassina Mouri

  2. GeoBioTec, Geosciences Department, University of Aveiro, Aveiro, Portugal

    Carla Candeias

  3. EpiUnit, Public Health Institute, University of Porto, Porto, Portugal

    Carla Candeias

  4. Environmental and Engineering Geology Division, Geological Survey of Namibia, Windhoek, Namibia

    Israel Hasheela

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Kambunga, S.N., Candeias, C., Hasheela, I. et al. Review of the nature of some geophagic materials and their potential health effects on pregnant women: some examples from Africa. Environ Geochem Health 41, 2949–2975 (2019). https://doi.org/10.1007/s10653-019-00288-5

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