BY TIFFANY CRAWFORD, POSTMEDIA NEWS
VANCOUVER — Researchers at the University of British Columbia have discovered a rare clay used as medicine by aboriginals in northern B.C. has properties that could be used to treat antibiotic-resistant bacteria.
Some 400 kilometres north of Vancouver, in Kisameet Bay on the Heiltsuk First Nation’s traditional territory, lies a 400-million-kilogram deposit of glacial clay that scientists believe was formed near the end of the last Ice Age, approximately 10,000 years ago.
The grey-green clay, known as Kisolite, has been used for centuries by the Heiltsuk to treat a range of ailments including ulcerative colitis, arthritis, neuritis, phlebitis, skin irritation and burns. Locals have also historically used the clay for eczema, acne and psoriasis.
UBC researchers say the clay exhibits potent antibacterial activity against multidrug-resistant pathogens.
Testing conducted by UBC microbiologist Julian Davies and UBC researcher Shekooh Behroozian found the clay, suspended in water, killed 16 strains of so-called ESKAPE* bacteria samples from sources including Vancouver General Hospital, St. Paul’s Hospital, and UBC’s waste water treatment pilot plant.
As a result of those tests, the scientists recommend the clay be studied as a clinical treatment for serious infections caused by ESKAPE strains of bacteria, a group of potentially deadly pathogens that cause many infections to “escape” antibiotics.
“Infections caused by ESKAPE bacteria are essentially untreatable and contribute to increasing mortality in hospitals,” said Davies, co-author of a paper published Tuesday in the American Society for Microbiology’s journal mBio.
The team was approached three years ago by Kisameet Glacial Clay, a company formed to market cosmetic and medicinal products made from the clay.
“They wanted microbial testing on clay, so I was a bit skeptical at first,” Davies said in an interview Tuesday. “Well, there are all sorts of claims out there, all kinds of folklore medicine and witchcraft.”
However, Davies and Behroozian were surprised to discover that properties in the leachate derived from the clay killed all 16 of the strains of bacteria tested.
Davies said that after 50 years of overusing antibiotics, ancient medicinals and other natural mineral-based agents may provide new weapons in the battle against multidrug-resistant pathogens.
He said no toxic side-effects have been reported in the human use of the clay. So the next stage in clinical evaluation would involve detailed clinical studies and testing on animals.
He said the antibacterial properties would be extracted from the mud and would likely be either injected into subjects or administered using a patch.
Researchers also need further study to understand how the clay works to destroy bacteria.
The research was partly funded by Kisameet Glacial Clay. The company says the colloidal clay from a shallow five-acre granite basin, nine metres above sea level, is hand-harvested by local Heiltsuk contractors.
The company has a memorandum of understanding with the Heiltsuk First Nation on extraction rights.
Kisameet Glacial Clay would like to begin marketing a line of cosmetic products, but does not want to wait until the healing properties can be scientifically proved, said company president Lawry Lund.
Lund said the clay found in Kisameet had been studied in the 1950s by Dr. Ernest Hauser of the Massachusetts Institute of Technology.
Hauser was the first to confirm First Nations claims that the clay had rare healing properties, Lund said, and so when they started looking again at the clay from a marketing perspective in 2006, they decided to confirm the old research.
A traditional use study co-sponsored by the Heiltsuk Integrated Resource Management group confirmed medicinal use of the clay in the late 1940s. However, Lund said, the use of clay by Heiltsuk people is quite limited at this time.
The company then joined up with the team at UBC to study the efficacy of the clay in a number of harmful bacterial pathogens.
“It’s very exciting, but there’s still a lot of fear and trepidation,” said Lund.
“We rely so much on these researchers and we are so grateful that we get to work with this team.”
Lund said there is still much work to be done to confirm the clay’s safety and efficacy. He added that, thanks to several private backers, the company will continue to fund UBC’s research.
* ESKAPE is an acronym used to summarize some of the most common resistant bacteria, namely: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa and Enterobacter species.