For years, we have been told to shop for Halloween costumes that are flame retardant. However, did you know that manufacturers are no longer required to make them flame-retardant? The Environmental Protection Agency announced earlier this year that the chemical that makes them fire-resistant includes PBD's, which have been shown to act as a thyroid disruptor. It is controversial.
The American Council on Science and Health says there is no credible evidence of any real danger to humans. Some costumes are still flame retardant. So, the EPA says that if you're worried, the best way to protect kids from PBD's is to wear a layer of clothing underneath the costume.