At least one of the three chemicals was detected in 47 of the 51 flavors tested. Diacetyl was detected above the laboratory limit of detection in 39 of the flavors tested. Acetoin and 2,3-pentanedione were detected in 46 and 23 and of the flavors, respectively.
The question is, how much? The lab limit of detection is often in the parts per billion or parts per trillion.
The dose makes the poison!
Hell, frying foods creates acrolein and acylamide which is toxic as hell (it alkylates glutathione, a key anti-oxidant in the body). However, you'd need to eat kilograms of fried food per day to actually reach a toxic level.
Coffee is another great example. It contains 23 known carcinogens.