I once heard that almost everything that gets into you slightly increases your risk of cancer (water is the exception), but there are different levels of risk.

I once heard that almost everything that gets into you slightly increases your risk of cancer (water is the exception), but there are different levels of risk. Some compounds will practically guarantee that you get tumors (like radiation, also benzene is really bad), but others are really negligible (like coffee or junk food, especially if you consume it rarely). So the important part is how much these compounds increase your risk of cancer. If a single day's exposure to a new car increases your risk of cancer enough to be noticeable than there's an issue. Otherwise just don't expose yourself to the smell often and you should be fine.