Geochemical composition and potential health risks of geophagic materials: an example from a rural area in the Limpopo Province of South Africa.
Bioaccessible fraction
Geophagic materials
Health risk assessment
South Africa
Journal
Environmental geochemistry and health
ISSN: 1573-2983
Titre abrégé: Environ Geochem Health
Pays: Netherlands
ID NLM: 8903118
Informations de publication
Date de publication:
Aug 2023
Aug 2023
Historique:
received:
24
06
2022
accepted:
24
03
2023
medline:
7
8
2023
pubmed:
10
6
2023
entrez:
9
6
2023
Statut:
ppublish
Résumé
Geophagy is a common practice among rural population of the Fetakgomo Tubatse Local Municipality area in the Limpopo Province of South Africa. Although, the practice might be beneficial to the health of the consumers, its negative effects could overshadow the positive effects and might lead to detrimental health issues. The present work sought to investigate the geochemical composition as well as pH and organic matter (OM) content of geophagic materials commonly consumed in the study area. Furthermore, assessment of the potential health risk of the materials on geophagic individuals was also considered. Twelve samples were collected in the study area and analysed by X-ray Fluorescence (XRF) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) for major and trace elements composition. The results showed higher concentrations of non-essential elements (e.g., As, Cr, Pb) than the proposed recommended daily standards intake, suggesting a potential health risk. The alkaline nature (pH 6.80 to 9.22) of the studied samples might affect the bioacessibility of some essential elements. Furthermore, the OM content (> 0.7%) observed in some of the studied samples may retain pathogenic micro-organisms detrimental to health. Although As and Cr presented a low bioaccessible fraction (< 16.0%), health risk assessment revealed that their concentrations represented a hazard (HQ > 1) and might induce non-carcinogenic health threats to geophagic individuals. Based on the geochemical analysis, pH and OM content as well as health risk assessment findings, the studied geophagic materials are not considered suitable for human consumption. The practice should therefore be discouraged amongst the population in the study area to avoid possible detrimental health issues.
Identifiants
pubmed: 37296282
doi: 10.1007/s10653-023-01551-6
pii: 10.1007/s10653-023-01551-6
pmc: PMC10403411
doi:
Substances chimiques
Soil
0
Trace Elements
0
Metals, Heavy
0
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
6305-6322Informations de copyright
© 2023. The Author(s).
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