Here are five articles on food irradiation:
http://www.cdc.gov/foodborneburden/
http://www.ars.usda.gov/main/site_main.htm?modecode=53-25-23-00
http://www.foodborneillness.com/
http://oss.mcgill.ca/yasked/foodirradiation.pdf
http://www.physics.isu.edu/radinf/food.htm.