CHAMPAIGN, IL (Chambana Today) – Tiny fragments of plastic known as nanoplastics are turning up everywhere—from drinking water and soil to the food on our plates. Now, new research from the University of Illinois suggests these microscopic particles may be making harmful bacteria like E. coli O157:H7 even more virulent.
In a groundbreaking study published in the Journal of Nanobiotechnology, scientists discovered that nanoplastics with a positive surface charge caused physiological stress in E. coli, triggering the bacteria to produce more of the Shiga-like toxin responsible for foodborne illness.
“Other studies have evaluated the interaction of nanoplastics and bacteria, but ours is the first to look specifically at their impact on human pathogenic bacteria,” said Dr. Pratik Banerjee, senior author and associate professor in the Department of Food Science and Human Nutrition at Illinois.
The researchers used polystyrene nanoplastics—common in takeout containers—engineered with positive, neutral, or negative charges. When introduced to E. coli in both free-floating and biofilm forms, only the positively charged particles caused the bacteria to become more toxic. “Our findings suggest that the surface charge of nanoplastics plays a significant role in bacterial behavior,” Banerjee said. “This could have far-reaching implications for food safety and public health.”
Biofilms, a protective coating formed by bacteria, offered limited defense against the stress induced by nanoplastics. The exposure not only made the bacteria more toxic, but also influenced their growth and colonization patterns. Ongoing research is examining whether nanoplastics also increase the transfer of antibiotic resistance genes in these bacterial communities—a development that could complicate treatment and containment of outbreaks.
The study was supported in part by the USDA National Institute of Food and Agriculture and is part of a broader effort to understand the health risks posed by the growing presence of plastic pollution.