The U.S. food industry is increasingly turning to irradiation to kill deadly bacteria such as E. coli and listeria in meat — a move environmentalists, food-safety advocates, and others say could amount to leaping from the frying pan into the fire. Irradiation uses high-energy electrons, gamma rays, or X-rays to kill bacteria. Critics say the process depletes vitamins and nutrients and leaves chemical byproducts in food. They also deride irradiation as a band-aid solution to the larger problems of filth and disease in the meat-production industry. The American Meat Institute estimates that under 5 percent of the 9 billion pounds of beef sold in the U.S. last year were irradiated, but it also predicts “exponential growth” in use of the technique. SureBeam, the largest beef irradiator in the country, expects to treat between 300 million and 350 million pounds of beef in 2003, up from roughly 15 million pounds last year.