Guys,
I found this site and couldn't believe it!
Home - Aerotoxic Association - Support for Aerotoxic Syndrome Sufferers Its all about Aerotoxic Syndrome which is a long term result of air coming through the air bleed valves and becoming contaminated which results in both pax and crew breathing in this horrible air.
Check out the ingredients of the Mobil Lubricant!
This may well be the cause of crew struggling to become pregnant. Forget radiation!