OCONOMOWOC, Wis. (WFLA) – A Wisconsin fire department posted on Facebook this week warning people about the dangers of leaving hand sanitizer in their vehicles on a hot day.

In a Facebook post showing a burned car door, the Western Lakes Fire District explained the dangers associated with hand sanitizer.

“By its nature, most hand sanitizer is alcohol-based and therefore flammable. Keeping it in your car during hot weather, exposing it to sun causing magnification of light through the bottle, and particularly being next to open flame while smoking in vehicles or grilling while enjoying this weekend can lead to disaster,” the fire department wrote.

A fire official said the image they shared was taken in Brazil after hand sanitizer contacted open flame. The department is encouraging people “to simply be careful and realize that a product we all use very frequently can be dangerous if it contacts open flame of any kind, but specifically cigarettes or those from grills.”

But can hand sanitizer really combust in a hot car?

It’s true that hand sanitizer, which contains alcohol, can ignite when near an open flame. However, Poynter said fact-checkers in Brazil concluded the temperature inside a car must reach at least 572 degrees for a bottle of hand sanitizer to combust.

According to a 2007 study of hand sanitizer used in hospitals, the World Health Organization said no reports of “fire caused by static electricity or other factors were received, nor were any related to storage areas.”