Can Shopping Make You Sick: We Test For Dangerous Bacteria

When you go to the store to pick up a few things, most of us use a shopping cart.  They're everywhere, and usually out of mind.

But have you thought that hundreds or thousands of others have had their hands right where you do... on the handles... in the baskets. We set out to learn whether those carts we use every day might make us sick, whether E.coli or Salmonella is common.

"If someone coughts on their hands and then grabs a cart, yeah, germs could be transmitted. We set out to find out. With the help of Dr. David Lakey of the University of Texas Health Center at Tyler, we are guided through the process.

This is a scientific process. There is a procedure to get everything right. We went to five stores: three supermarkets, a drugstore, and a discount retailer.  Using the instructions from U.T. Health Center, one cart at each location is examined.  Each sample is sealed in its own tube, and labeled. We repeated the process over and over and over again. Some of the carts were so dirty the swab began to turn dark. But might what's on this, make us sick?

So to the lab we go. The samples are placed immediately on the Petri dishes. And not only the swabs from the carts, we checked a tabletop, and the ultimate control sample -- the human hand, specifically mine -- unwashed -- and then after washing with antibacterial soap more than 15 seconds.

The fingers again pressed on the plate.

"Bacteria can live 24 hours or 48 hours on an inanimate object. If you don't clean it off," Lakey says.

The samples grow for several days.

Reporter: "Did you expect to find something there?"

Lakey: "I thought you'd find a few more bacteria there."

"The lower basket had a few bacteria, but they were common bacteria that is on a hand. No pathogens [that would] cause illness," Lakey says.

For several other stores, they just had tens to a few hundred colonies of bacteria.  Others might have had visible dirt, but of the 15 samples tested from shopping carts, only four had any detectable bacteria.

"It's not something that we would have concerns with causing illness," he adds.

So we took three samples, from carts at five different locations, and at each one of those locations, we didn't find as many bacteria, as on the human hand.

"The most bacteria were found on hands before washing, greater than 300,000 colony forming units of coagulate negative staph, the same organism that we found 10 colony forming units on the handle."

Just a few on the carts versus more than 300,000 on my fingers.

"That is a normal amount -- that number is normal. If you swab anyone's skin, you're going to find that organism there," Lakey says.

So to find a few of them on a shopping cart isn't so surprising. But after washing with antibacterial soap, the count was still around 100,000 colonies on my fingers. Lakey says testing only five carts probably prevented us from finding germs that could make us sick. So whenever you go to the store, he has this advice.

"There is a potential for raw meat having bacteria in it and if it's put on a surface, you can transmait whatever bacteria, germs or there to someone else," Lakey says.  He says the best thing all of us can do to stay well, is to keep our hands as clean as we can. Dr. Lakey suggests using alcohol-based hand sanitizer after handling carts or anything else others touch.  They're a very effective defense against getting sick. Also, several supermarket chains and other stores offer antibacterial or cleansing wipes you can use on the carts themselves.