Carmel on the Case: Lettuce Warn You

WSVN -- Shopping, chopping, slicing and dicing -- it takes a whole lot of work to make a salad. That's why pre-washed, bagged salads are flying off grocery store shelves.

Juan Carlos Gutierrez: "As far as salads, I like to eat bagged lettuce."

Businessman Juan Carlos Gutierrez is either crunched for time or doing crunches at the gym.

So, when it's time to eat, he reaches for a bag.

Juan Carlos Gutierrez: "It's convenient. It's supposed to be pre-washed, and, to the best of my knowledge, it is."

But is pre-washing good enough?

We decided to find out.

We bought and tested a caesar salad kit, a bag of iceberg lettuce mixed with carrots and cabbage, a triple washed spinach and another spinach that clearly says the buyer should "re-wash."

Dr. Pete Kmieck: "The findings were very interesting."

Microbiologist Dr. Pete Kmieck says a certain amount of bacteria can be expected.

But the levels in some salads we tested concerned him.

Dr. Pete Kmieck: "In two of our samples it exceeded the upper limits of our test range to measure it, and these samples would be considered high in coliform bacteria."

Coliform bacteria are common in the environment but some can cause physical problems.

Dr. Gary Luckman: "Gastroenteritis is a kind of illness where you get nausea and vomiting and diarrhea, sometimes fever and chills and cramps."

And sickness from contaminated food can be deadly.

Jeff Allgood: "That's what we suspected -- bad spinach, didn't use it anymore after that."

Last October a 2-year-old Idaho boy died from kidney failure associated with an E. coli outbreak in bagged spinach.

Robyn Allgood: "We've been through all the range of emotions the grief, the sadness, the guilt."

So far, four people have died in the outbreak and became sick.

Caroline Smith Dewaal: "I think we're going to see many more outbreaks and more deadly outbreaks from these bagged salad products."

The national watchdog group, Center for Science in the Public Interest, says when it comes to dirty salad greens, the produce industry has a big responsibility.

Caroline Smith Dewaal: "What the industry needs to do is ensure that animal waste and human waste is kept off these leafy green products."

Carmel Cafiero: "And that's hard to do. Contamination from one field can spread because greens from multiple fields are mixed together during processing. That means deadly E. coli could end up in bagged salads sold nationwide."

And critics say that sometimes the water used to clean the greens isn't changed as often as it should be.

So all the washing in the world may not make a difference.

Caroline Smith Dewaal: "Most salad processors use chlorine to control the bacteria that may show up on the products."

But the industry insists its products are safe.

The United Fresh Produce Association told us:

"The fresh cut produce that's triple washed or ready-to-eat has been handled in a state of the art facility that cleans it better than anybody can do in their own kitchen."

Still, the Food and Drug Administration has expressed "serious concern with continuing outbreaks of food borne illness associated with fresh and fresh cut lettuce."

Luckily, none of the South Florida salads tested positive for E. coli.

But the bags with the highest coliform bacteria were the iceberg mix and the spinach you're supposed to re-wash.

Dr Pete Kmieck: "When you're buying a produced product, and you're using it without rinsing or washing it, you're relying totally on the producer."

As for Juan Carlos, after hearing our test results he says he'll think twice before going from bag to bite.

Juan Carlos Gutierrez: "I do rinse my broccoli and I rinse my asparagus and maybe it's time for me to start rinsing my pre-cut bags of lettuce."

And you might want to also -- because as long as the produce industry is allowed to police itself -- "Lettuce" Warn You -- don't assume clean lettuce is in the bag.