Packaging may be boosting the toxicity of food-poisoning bacteria, according to a food science study at the University of Illinois at Urbana-Champaign.
The researchers found that exposure to nanoplastics inflicted physiological stress in the deadly E. coli strain O157:H7, causing the bacteria to increase production of the Shiga-like toxin that sickens humans, said the research team led by Pratik Banerjee, associate professor in food science in the university’s College of Agricultural, Consumer and Environmental Sciences.
“Other studies have evaluated the interaction of nanoplastics and bacteria, but so far, ours is the first to look at the impacts of microplastics and nanoplastics on human pathogenic bacteria,” Banerjee said.
The work found that nanoplastics — generated in the study from polystyrene, which is in most food service clamshell boxes — specifically with positively charged surfaces stressed the E. coli cells, which have a negative surface charge.
“We started with the surface charge. Plastics have an enormous ability to absorb chemicals. Each chemical has a different effect on surface charge, based on how much chemical is adsorbed and on what kind of plastic,” Banerjee said.
“We didn’t look at the effects of the chemicals themselves in this paper — that’s our next study — but this is the first step in understanding how the surface charge of plastics impacts pathogenic E. coli response.”
