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Fighting staphylococcus aureus with clay?
There are not many alternative solutions for dealing with bacteria which are becoming more and more resistant to antibiotics. A recent study brings a ray of hope, showing that the ionic composition of clay might grant it antibacterial benefits.
In the fight against bacteria the scope of actions is increasingly limited. Antibiotics, which seemed to be the miracle cure for many infections less than a century ago, are now obsolete. Bacteria communicate with each other and exchange resistance genes which allow them to combat antibacterials. Resistance to multiple antibiotics has become a major public health problem, and new treatments are necessary.
Clay is a therapeutic substance which has been used since ancient times. (The) Egyptians used it in the mummification process, and to treat diarrhea, abscesses and injuries. During the First World War, German and Austrian doctors also used it to cure dysentery, which is an infectious disease of the colon. Nowadays clay is used in naturopathy or in beauty treatments.
A team from Arizona State University has just published a study in Plos One, that highlights the role of clay in eliminating pathogenic bacteria, such as Escheria coli or staphylococcus aureus. The latter is responsible for numerous serious infections that can (even) lead to death. Moreover, the appearance of staph A strains which are resistant to antibiotics and called MRSA makes their eradication extremely tough.
Clay has antibacterial properties
In this study, the scientists examined four clay samples which were more or less able to eliminate E coli and MRSA. In order to identify the elements of clay which are responsible for this antibacterial action, they compared their ionic composition. Their analysis shows that the soluble fractions vary according to the metallic ions they contain, such as iron, copper, cobalt, nickel and zinc (ions).
More advanced experiments showed that an increase in the concentrations of zinc, nickel, cobalt and copper induced an antimicrobial effect against E. coli. In order to destroy the MRSA the concentrations of zinc, cobalt and copper are crucial. Nevertheless, the quantity of ions isn’t a satisfactory criterion and other parameters, like pH, ion solubility or temperature affect the antibacterial properties of clay.
According to the authors, clay might be an effective alternative treatment against bacteria which are becoming more and more resistant to antibiotics. However, these materials can contain toxic metals like lead or mercury. Precautions need to be taken in order to minimize the risk of exposure.