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Member Research & Reports

Member Research & Reports

Harvard Finds Nano-sized, Charged Water Particles Can Inactivate Foodborne Bacteria

In a U.S. Department of Agriculture-funded study published in the journal Environmental Science & Technology, Dr. Philip Demokritou, associate professor of aerosol physics and director of the Laboratory for Environmental Health NanoSciences at Harvard T.H. Chan School of Public Health, and colleagues describe how nano-sized, charged water particles called Engineered Water Nanostructures (EWNS) can inactivate foodborne bacteria on both stainless steel surfaces and on the surfaces of tomatoes. They found a dose-response relationship in the study; that is, the more EWNS they used, and the longer the EWNS were in contact with the pathogens, the more the deadly bugs were destroyed.

Results from the study suggest that the new nanotechnology-based approach could provide an environmentally friendly and inexpensive alternative to current food decontamination methods, which often involve substances containing chlorine or ammonia that can leave unhealthy residue on produce.

“We cannot continue to battle infectious diseases using chemical warfare,” said Dr. Demokritou. “This new method is chemical-free, leaves no residues, and uses very little electricity.” Preliminary findings also suggest that inhalation of EWNS appears to be safe — in a study led by Dr. Demokritou and his team last year, the researchers found that mice exposed to inhaled EWNS showed no adverse lung injury and inflammation at doses higher than those used in airborne bacteria inactivation experiments. Read more