Special Report: Gross-ery Bags

Shoppers are no longer choosing between paper or plastic, now they're bringing their own reusable bags to supermarkets. But there's a hidden drawback behind this convenient, environmentally friendly choice. 7's Sorboni Banerjee reveals what's inside these "Gross-ery Bags."

Reusable, recyclable, eco-friendly grocery bags are becoming super popular at supermarkets.

Kelcy Scolnick, Shopper

"I try and use them every time I go out."

Bradley Gibson, Shopper

"Use reusable bags. It's the best thing for our Earth."

They're great for our planet, but are they great for your family?

7NEWS looked closely inside some of these bags and found something potentially dangerous lurking inside.

We chose shoppers at random and asked them if we could take a closer look at six of their bags.

Fenwick Smith of Jamaica Plain has been toting his around for years.

Fenwick Smith, Bag Owner

"I use it at least once a week, more likely twice."

In his bag: sugar and vitamins.

In one woman's bag: potato chips and packaged goods.

In another bag: a key lime pie.

These two bags were full of fruits and veggies.

But it's what you can't see that would make you lose your appetite.

We swabbed the inside of each bag and sent the samples off to a lab.

And here's what we found:

Four of the six bags tested positive for bacteria.

Half of the bags had mold inside them.

And all but one of the bags had yeast.

Dr. Khalil Zadeh, Lapuck Laboratories, Inc.

"The laboratory results are definitely significant. They are high enough to issue a warning."

The problem: what's in your bag can get on to your groceries and even onto your dinner table!

And that could make you and your family sick.

Joan Salge Blake, Registered Dietitian & Boston University Nutrition Professor

"What you have to really be careful about is that cross-contamination. That, that bacteria or the pathogens that might be in the raw meats touching or coming in contact with the foods that are raw, like your produce, that you may eat."

To keep your food free of harmful bacteria and mold use different bags for meat and ready-to-eat foods like fruits and vegetables and clean your bags regularly.

Caitlyn Petruccio, Shopper

"I'll probably just wash it."

George Anderson, Shopper

"I was gonna say I'll just wash it every once in a while. I'm sure it will be fine."

Allegra Levy, Shopper

"It's important to use the reusable bags and to use them properly."

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