Traditional wire metal brushes are dangerous because as the brush ages, the tiny wire bristles can fall off and stick to your grill, or even worse your food. If ingested the tiny bristles can become lodged in your throat, stomach or intestines causing illness or damage to your insides.
For more information check out these media releases:
Doctors Warn About Dangers of Grill Brushes - WSMV News 4
New Standard - Global News
Guard Against Grill Brush Dangers - Consumer Reports
Wood is a great and safe alternative to the traditional brushes to clean your gill between meals. It forms to your barbecue grates no matter the shape or size and knocks off any stuck on food.
** Harmsen's Hockey recommends that periodically you remove your grates and do a thorough cleaning of them. Please consult your barbecues user guide or company website for best cleaning practices **