The replacement lid for the bath bomb kit has two holes in it to allow gas to escape. The original lid has no holes. (U.S. Consumer Product Safety Commission)

At least 13 people have been injured by exploding containers used to hold materials to make "bath bombs" or bath balls, the U.S. Consumer Product Safety Commission reported Friday.

A buildup of carbon dioxide has popped the caps off 88 jars of bath bombs/balls or bath fizzies found in Spa Factory's Aromatherapy Fountain kits and Spa Factory's Bath Benefits kits, the commission said.

The flying caps have hurt children, including causing two eye injuries, a cheek welt, a cheek cut and irritated eyes.

"Injuries to adults include four reports of bruising, one swollen joint, and one face gash," the commission said in a recall notice.

Consumers should immediately stop using the products, the notice said.

Health Canada said it is aware of the situation. The product was sold in Canada, and "the department is in the process of gathering Canadian-specific information, including numbers and distribution, as well as instructions for consumers regarding how the recall is being handled," a spokeswoman said in a emailed note.

The mixture in the bath bombs/balls or bath fizzies may include citric acid, which could further irritate eyes.

The importer of the Chinese product, JAKKS Pacific Inc. of Malibu, Calif., has recalled about 516,000 of the kits.

They were sold at Sam's Club, Wal-Mart, Target, and toy stores across the U.S. from August 2008 to January 2009. The products cost about $13 US for the Bath Benefits Kit and between $30 and $50 for the Aromatherapy Fountain.

The purple caps on the recalled products are found on Spa Factory's Bath Benefits Kit (model 37836), Deluxe Spa Fantasy Aromatherapy Fountain (model 37908), Spa Fantasy Aromatherapy Fountain (model 37837), Spa Fantasy Aromatherapy Fountain (model 54892) and Spa Fantasy Aromatherapy Fountain (model 54857).

JAKKS is offering a replacement cap with vent holes.

"After testing potential solutions, we found that placing two small holes in the caps adequately allows all built up pressure to escape, thereby preventing the caps from flying off," the company said on its website.

The company can be reached at (877) 875-2557.