The Facilities Aren't Up to Par
If you think the stinky socks and dirty gym shorts that litter your kid's room are a health hazard, then you might want to forgo sending him to summer camp.
Camps are notoriously dirty, as the facilities are usually left unattended for the majority of the year or are repurposed housing, such as old college dorms. Either way, the lighting, plumbing, cooking facilities and even the structural integrity of the buildings themselves may be lacking, so if sanitation is a concern, insist on a personal tour of the entire camp before writing any checks.
Oh, and while you're there, look out for bugs. While you can't get around critters in the woods, living and dining areas should be relatively pest-free. If they're scuttling around under the floorboards or even scurrying out in the open, that's not ideal for little bare feet.