Now spinach and iceberg lettuce can be treated with enough radiation to kill bacteria such as E. coli and salmonella, which can cause food poisoning. The FDA issued food-irradiation in the wake of recent salmonella and E. coli outbreaks, such as the 2006 E. coli outbreak that pulled fresh spinach off store shelves. The rule -- which only applies to spinach and iceberg lettuce -- doesn't require irradiation. It just permits it.
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