The FDA’s approval last month of the irradiation treatment of spinach and lettuce to kill the potential harmful bacteria, pathogens and insects, including causes of food-borne illnesses like E. coli and salmonella has stirred a long debate about how to improve the safety of food.

There are about 76 million cases of food poisoning annually, according to the Centers for Disease Control and Prevention. Infected people usually experience a wide variety of symptoms including abdominal cramps, nausea, vomiting and diarrhea. Foodborne diseases cause approximately 325,000 hospitalizations, and 5,000 deaths each year in the United States, according to the CDC.

Trials conducted in the field of food irradiation by the U.S. Department of Agriculture have shown that treating spinach and lettuce with relatively low radiation kills 99.9% to 99.99 % of E.coli.

The FDA’s decision was criticised by some consumer groups and by foodmakers who say it will take time and money to make the treatment practical.

The FDA’s approval of food irradiation treatment followed the 2006 E.coli outbreak that pulled fresh spinach off store shelves and sickened dozens of consumers.

However, the FDA doesn’t have any plans to allow the irradiation of any other vegetables so far.

“The agency has determined that this action is of a type that does not individually or cumulatively have a significant effect on the human environment,” the FDA said.

Officials of the nonprofit Food & Water Watch Agency claim that there is far too little information on the effects of a long term use of irradiated vegetables, to allow such a measure. FDA claims the procedure is extremely safe and it would not allow a procedure that would stop a disease and cause another.