Parents are being urged to watch out for more than just the usual hazards when shopping for toys this holiday season.

Toys that have small parts are still the most common danger.

Coin-size lithium batteries in many toys and electronic devices can pose another big problem if kids swallow them, said Carol Ann Giardelli, director of Safe Kids New Jersey.

"When a button battery gets stuck in a child's throat, the saliva triggers an electrical current," she said. "This causes a chemical reaction that can cause severe damage and burns to the esophagus."

Parents who suspect a child has swallowed one of those batteries should immediately rush to the emergency room because severe injury can occur within a couple of hours, Giardelli said.

Peter Skopec of the New Jersey Public Interest Research Group agrees that the most common danger comes from toys with small parts that young children can swallow.

"A great way to test whether a toy is a choking hazard is by using an empty toilet paper roll," he said. "If the toy fits inside the empty toilet paper roll, then it is too small for kids under the age of 3."

The national report from the Public Interest Research Group found there are still toys for sale that have high levels of toxic chemicals, and some that produce noises loud enough to damage hearing. The group also has provided a list of safety tips.