Does Washing Fruits and Vegetables Make Them Safe?

Washing fruits and vegetables is smart. But can it keep you safe from bacteria outbreaks like the recent tomato scare?
While rinsing a tomato under cold water rids the produce of a lot of potentially harmful bacteria, some of these tiny critters are resistant to the shower. Basically, they hang on tight, experts say.

The result can be outbreaks of Salmonella or E. coli in humans, even if we're careful.
Tomatoes can pick up such a pathogen from contaminated soil, irrigation water, manure, wildlife, or farm workers.
"If you've got bacteria on the surface of fruits and vegetables, and you give them a wash with cold water, it removes some of what's on the surface," Niemira told LiveScience. "Unfortunately, it [cold water rinsing] doesn't remove all of them, and that's a problem. If things are well attached or living in a tight-knit community called a biofilm, that's going to be hard to get rid of."

Rough surfaces, like those on cantaloupes and spinach, provide lots of nooks and crannies in which bacteria can hide out, Niemira said. Tomatoes are much smoother, though their surfaces do contain tiny pores that make homes for bacteria.
You would want to wash rougher-surfaced fruit more carefully. Niemira cautions, however, too rough of a cleaning can bruise or tear the protective layer covering tomatoes and other fruits and vegetables.

Damage to the produce can lead to spoilage, and the associated "spoilage bacteria." While these bacteria aren't harmful to humans, the organisms make produce mushy and provide more hangouts for human pathogens, such as Salmonella, Niemira explained.