lurks in the bins and scraps in shops. It's just wood right?.... well for some folks peanuts are a problem. Some woods used by woodworkers are dangerous to some woodworkers so safety precautions are are a reality. Here is a list of potentioal problems.
http://www.tedswoodworking.com/toxic-wood.htmMasks, gloves in some cases, protective clothing, environmental safety fixtures all need consideration. Note, the tab at the bottom of the article about wood species pictures, could be a good resource for you to bookmark.