How About Them (Dirty) Apples?

A local lab reveals the sickening stuff that rubs off on your fruits and veggies

Selma90, Flickr

New testing done at a San Diego lab will probably make you think carefully about how long you wash the produce you serve to your family.

Quadrants Scientific, Inc. President Mark Shannon tested six apples purchased from grocery stores around San Diego for microorganisms. Half were washed for fifteen seconds with cold water (the minimum recommended by the USDA).  The other apples were tested just as they came out of the stores.

Technicians found about a quarter million microorganisms on the surface of the unwashed apples, compared with only about 5,000 on the washed ones. It was a similar story when they tested a carrot.

They identified at least three different microorganisms on the washed apples: Kocuria rosea, Bacillus megaterium and Leifsonia aquaticum. The microorganisms were in low enough numbers that Shannon was not alarmed. But he says if someone ate high concentrations of the microorganisms, they might get sick.

"It's a numbers game, the body can only take too much of an insult so we don't want to be adding too much bacteria we want to keep it as little as possible," Shannon said.

He says the elderly, young children and people with compromised immune systems would be most at risk.

Shannon says vigorously washing the apples for 15 seconds in cold water reduced those microorganisms by 98 percent.

"Now I'm probably going to put a timer on my kitchen sink and make sure I hit the thirty second mark," said Sugar Jones, a mother of two and a consumer columnist for the website

 Jones says she has often wondered about how many people have handled the produce she buys for her family, so she washes most food with a scrub brush.

"I really don't want them getting sick off of something that's supposed to be healthy for them," Jones says.

The good news?  The apples tested at Quadrants Scientific did not show a trace of what Shannon says would be the biggest concern:  fecal contamination.

Shannon also says you should even wash produce even if you wont eat the peel or skin.  He says, when you cut into produce, you're going to push the microorganisms that are on the skin or peel into the meat.  So when you eat the meat, you also eat those microorganisms dragged into it by the knife.

According to the Centers for Disease control, one in six people are expected to get a food-borne illness every year and about 3,000 people die.

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