McDonald's recalls 33 million unsafe activity trackers included in Happy Meals

McDonald's recalls 29 million activity wristbands in the U.S. and 3.6 million in Canada because they are at risk of irritating or burning a wearer's skin.

The quick service restaurant chain had been including the "step-it" activity trackers in Happy Meals as part of a child fitness promotion between August 9 and 17ththis year. They came in two styles Activity Counterand a motion-activated Light-Up Band.

The Activity Counter comes in translucent plastic orange, blue or green, and features a digital screen that tracks a child's steps or other movement. The Light-Up Band comes in translucent plastic red, purple, or orange, and blinks light with the child's movement.

The devices are being recalled after at least 70 people developed blisters andother problems.

"Consumers should immediately take the recalled wristbands from children and return them to any McDonald's for a free replacement toy and either a yogurt tube or bag of apple slices," the U.S. Consumer Product Safety Commission says.