Protecting consumers from the virtues of anti-microbial agents

November / December 2018
GREEN CHEMISTRY

University of Victoria civil engineering Professor Heather Buckley led a team that has won an international award for its contribution to resolving one of the leading challenges surrounding the use of anti-microbial chemicals: how to employ them sufficiently to keep infection at bay without providing infectious agents with the opportunity to develop a resistance to this effect.

University of Victoria civil engineering Professor Heather Buckley

University of Victoria civil engineering Professor Heather Buckley. Photo credit: University of Victoria

“Any time you introduce something into the environment designed to kill off bacteria and mold, it’s part of a cumulative stress on the environment,” she explains.

Among the most widely used examples of these stressors are preservatives such as parabens and methylisothiazolinone, which prevent micro-organisms from getting into a wide range of personal-care and household products. Such formulation makes these products safer to use, but since most of them end up going down drains, they introduce these agents to the surrounding environment, where they are encountered by huge populations of micro-organisms, some of which will survive and pass their resistance on to descendants.

Faced with the prospect that anti-microbial compounds may simply become useless against ensuing generations of bacteria and mold, Buckley and others have been exploring ways of preventing this widespread exposure from occurring. It was a problem she first tackled while working at the University of California Berkeley’s Center for Green Chemistry, then carried on when she joined the University of Victoria.

Earlier this year she led a 10-member team that included Berkeley researchers, members of the US Department of Agriculture, and representatives of companies that develop environmentally friendly alternatives to traditional soaps and cleaning materials. Together they won a competition mounted by the Massachusetts-based Green Chemistry and Commerce Council (GC3), which wanted to attract outstanding examples of innovative environmental solutions to practical commercial problems.

What distinguished the team’s contribution was a unique “reversible” feature. Their anti-microbial agent includes two proprietary components that form a biologically active dimer once they are added to a product such as shampoo. Once they have been diluted by use, however, they revert to their inert forms. When they ultimately find their way into the surrounding environment, they will be unable to contribute to helping microorganisms develop any kind of resistance to their active form.

“It is inherently non-toxic at the end of life,” notes Buckley, adding that these constituents are also biodegradable.

The GC3 award included prize money that is being split amongst the team members. UVic’s share will be supporting a graduate student investigating how this same reversible strategy can be applied to water treatment and storage in order to avoid the use of harsh disinfectants like chlorine. Buckley envisions the usage of anti-microbial agents becoming much more limited, so that their effectiveness remains focused only on those points in a product life-cycle where it is needed.

“Microbial resistance is something that is crucial for people as the immediate users," she says. "It’s crucial in terms of population health, and it’s really crucial if you think about those who are being exposed to high levels of these chemicals during their production.”