This is something I've worried about too.
I'd love to see results from studies on this. Unfortunately I have none to share.
I do have this to say. The human body is not as 'fragile' as people like to think. It has evolved with the environment for hundreds of thousands of years (this is true, regardless of your beliefs about where we originally came from). When I bite into an apple, receptors in my body 'designed' to fit with compounds in the apple, compounds that have been there for, again, hundreds of thousands of years, start working. It may make me feel good...or it may tell me that this was a bad apple, and I'll feel sick. But it won't do anything weird, it won't mess with my DNA. I won't get cancer.
This is the reason that GMOs and synthetic chemicals in today's food worries me. 50 years ago, all food was organic. We didn't need a label. Now, the list of ingredients in a McDonald's meal includes compounds that didn't exist in the past century.
What effects do all these new compounds have? We have no idea...and that is the point. That's why, imo, it seems that a new study every day finds out that something new is, actually, a carcinogen.
Long story short (because some of that was really off-topic), I try to use this philosophy when considering health effects of foods, or anything. Is char a carcinogen? Maybe so...but I really do doubt it's more of a risk than, say, constantly walking in a sea of radiation from our cell towers and wifi. Or even driving in a car every day. A stretch with this example - but again, cars have not evolved along with humans. We use them regularly now, and the result? It's one of the leading causes of death, period.
But char? I'd like to think our ancestors didn't start killing themselves when they learned to control fire.
Bottom line: Ignore everything I said, except the second sentence. Listen to the studies. Does anyone have any?