Cardiff Metropolitan University
biomolecules-11-00058-v4.pdf (766.63 kB)

A New Look at the Purported Health Benefits of Commercial and Natural Clays

Download (766.63 kB)
journal contribution
posted on 2022-03-14, 17:00 authored by Alexander Incledion, Megan Boseley, Rachael L Moses, Ryan Moseley, Katja E. Hill, David W. Thomas, Rachel A. Adams
: Clays attributed to have medicinal properties have been used since prehistoric times and are still used today as complementary medicines, which has given rise to unregulated “bioceutical” clays to treat skin conditions. Recently, clays with antibacterial characteristics have been proposed as alternatives to antibiotics, potentially overcoming modern day antibiotic resistance. Clays with suggested antibacterial properties were examined to establish their effects on common woundinfecting bacteria. Geochemical, microscopical, and toxicological characterization of clay particulates, their suspensions and filtered leachates was performed on THP-1 and HaCaT cell lines. Cytoskeletal toxicity, cell proliferation/viability (MTT assays), and migration (scratch wounds) were further evaluated. Clays were assayed for antibacterial efficacy using minimum inhibitory concentration assays. All clays possessed a mineral content with antibacterial potential; however, clay leachates contained insufficient ions to have any antibacterial effects. All clay leachates displayed toxicity towards THP-1 monocytes, while clay suspensions showed less toxicity, suggesting immunogenicity. Reduced clay cytotoxicity on HaCaTs was shown, as many leachates stimulated wound-healing responses. The “Green” clay exhibited antibacterial effects and only in suspension, which was lost upon neutralization. pH and its interaction with clay particle surface charge is more significant than previously understood to emphasize dangers of unregulated marketing and unsubstantiated bioceutical claims.


Published in





  • VoR (Version of Record)


Incledion A, Boseley M, Moses RL, Moseley R, Hill KE, Thomas DW, Adams RA, Jones TP, BéruBé KA (2021).' A New Look at the Purported Health Benefits of Commercial and Natural Clays', Biomolecules.11(1):58.

Electronic ISSN


Cardiff Met Affiliation

  • Cardiff School of Sport and Health Sciences

Cardiff Met Authors

Rachel Adams

Cardiff Met Research Centre/Group

  • Cardiovascular Metabolism and Inflammation

Copyright Holder

  • © The Authors


  • en

Usage metrics

    Cardiovascular Health & Ageing - Journal Articles