A congressional committee is demanding an explanation from the Kellogg Company regarding what led to the recall of millions of cereal boxes that made several people sick.

In June, Kellogg recalled 28 million boxes of Apple Jacks, Corn Pops, and Fruit Loops cereal after complaints of an unusual flavor and smell.

An investigation by the cereal maker identified the chemical hydrocarbon as the source.
    
The chemical has been approved by the Food and Drug Administration and is often used as a protective coating for foods like cheese and raw fruits and vegetables.
    
However, higher than normal amounts of the substance were found to be used in the boxes. Lawmakers on the Committee on Energy and Commerce raised a number of concerns about the chemical.

"At least one study has shown that 2-methylnaphthalene may cause lung injuries in adults. There are no studies indicating whether children are more susceptible to this chemical," Reps. Henry Waxman, D-Calif., and Bart Stupak, D-Mich., wrote in a letter to the company.
    
Meanwhile, Kellogg has stopped using the packaging liner, saying it won't use it again.