[Para. 1 of Summary] Biofilms occur when microbes attach to surfaces in a matrix of self-produced slime,” says Evan Ronan, currently a PhD student in Ryerson’s Environmental Applied Science and Management Program. “They’re also notoriously difficult to eradicate,” he adds. “This is of particular concern when biofilms form on medical devices implanted in the human body – at least one half of all hospital-acquired infections can be attributed to biofilm growth.”