(NaturalNews) Naturally occurring clay may turn out to be one of the most effective ways to kill antibiotic-resistant superbugs, according to a study conducted by researchers from Arizona State University and published in the journal Environmental Geochemistry and Health.
"Minerals have long had a role in non-traditional medicine," said Enriqueta Barrera of the National Science Foundation's Division of Earth Sciences, which funded the study. "Yet there is often no understanding of the reaction between the minerals and the human body or agents that cause illness. This research explains the mechanism by which clay minerals interfere with the functioning of pathogenic bacteria."
The key to stopping superbugs?
According to researcher Lynda Williams, clay minerals have been used in many traditional medical systems for thousands of years. Relatively recently, green clays found only in France and traditionally used in French mineral baths were proven to have antibacterial properties. Indeed, the green clays were used effectively to treats Mycobacterium ulcerans, a bacterial species that causes the skin disease known as Buruli ulcers.
"These clays," Williams said, "demonstrated a unique ability to kill bacteria while promoting skin cell growth."
Buruli ulcers begin as painful swelling of the skin but can eventually lead to large, open ulcers on the arms and legs. If untreated, the disease can lead to permanent deformity and even secondary infections that can cause death.
The French green clay was eventually depleted, however, and scientists have been searching for viable replacements. The value of antibacterial clay has become even higher as more and more pathogens continue to develop resistance to numerous forms of pharmaceutical antibiotics.
"As antibiotic-resistant bacterial strains emerge and pose increasing health risks," Williams said, "new antibacterial agents are urgently needed."
Indeed, multi-drug-resistant bacteria are now so prevalent and dangerous that they are considered a global health concern.
"This serious threat is no longer a prediction for the future," reads a 2014 World Health Organization report, "it's happening right now in every region of the world and has the potential to affect anyone, of any age, in any country."
Clays kill MRSA, E. coli
The new study identifies and partially explains antibacterial properties in clays extracted from a volcanic deposit near Crater Lake, Oregon. The tests were conducted using the bacterial species Escherichia coli and Staphylococcus epidermidis, which are common causes of human digestive and skin infections, respectively.
The researchers found that the clays flooded the bacterial cells with iron, overwhelming their ability to store the mineral and eventually killing them.
In addition, the researchers found that clays with antibacterial activity tend to be more acidic, thereby creating an environment more hostile to bacteria. This is particularly significant, since chronic, non-healing wounds tend to have a higher pH (i.e., less acidity and more alkalinity) than healthy skin. This same principle is used in many current wound treatments, such as acidified nitrate.
"Antibacterial clays can buffer wounds to a low [more acidic] pH," Williams said. "The clays may shift the wound environment to a pH range that favors healing, while killing invading bacteria."
Clays extracted from the Crater Lake region have also shown antibacterial activity against superbugs including methicillin-resistant S. aureus (MRSA) and extended-spectrum beta-lactamase-resistant E. coli (ESBL).
"To date," Williams said, "the most effective antibacterial clays are those from the Oregon deposit."
Even in the Oregon deposit, not all clays were equally potent. Apparently, the geologic history (and thus chemical composition) of the clays plays a key role. The researchers found that two blue clays from the deposit were very effective against E. coli and S. epidermidis, while a white clay was 56 percent effective against E. coli and 29 percent effective against S. epidermidis. A red clay had no effect.