Could Radiation Make Seafood Safer?

Electron-beam pasteurization could reduce the risk of infection with viral pathogens from raw shellfish by 26 percent to 91 percent, depending on the pathogen, according to new research from scientists at Texas A&M University.

The research team, led by Suresh Pillai, PhD, professor of microbiology and director of the National Center for Electron Beam Research at Texas A&M, evaluated the degree to which electronic beam irradiation inactivated two common viral pathogens, hepatitis A and norovirus, in raw oysters. If a typical serving of 12 raw oysters were contaminated with approximately 100 hepatitis A and human noroviruses, they found that an e-beam dose of 5 kGy (kilograys) would achieve a 91 percent reduction of hepatitis A infection risks and a 26 percent reduction of norovirus infection risks.

“Most studies of this technology to date have said, ‘You will kill off the pathogen if you use this dose,’” says Dr. Pillai. “But ours is the first to show the potential reduction in public health risk. To do that type of work, you must have the right type of epidemiologists and risk assessment scientists on the team. We are fortunate to have those experts from the University of Texas School of Public Health, which allows us to make our data set a risk communication and risk management tool.”

That slant to things matters, says Dr. Pillai, because although electron-beam pasteurization was approved by the FDA nearly 10 years ago, but to date, only gamma radiation is used in the pasteurization of raw shellfish, and on only a small percentage at that.

“People in the food industry assume that consumers will not buy irradiated products, which is not true,” he says. “There are increasing numbers of irradiated fruits and vegetables on the market. For example, certain fruits like guavas and mangos from some parts of the world can only come into this country after irradiation, and they all bear the symbol. Not one product has been taken off the shelf due to consumer concerns.”