Spent some time looking for information.
https://youtu.be/3dsDznr4z5w
Aerotoxic Association - Aerotoxic Association
Personal experience: I flew the CRJ200 for about 6 years. Then I went to fly newer corporate aircraft and fly less. What I thought was interesting was I would get a bad cough that hurt and felt infected often when I was flying at the regional airline in the CRJ200. After leaving and flying newer aircraft and less hours my cough was gone and never returned. I have not been flying much for a few years and again I never get the same cough.