As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER T/O, F/A REPORTED A STRONG ELEC/CHEM ODOR COMING FROM THE AFT OF A/C. ODOR BECAME SO STRONG F/A COULD NOT GO AFT OF THE GALLEY. EMERGENCY LANDING BY CREW AT YYZ. CAPT REFUSED AIRCRAFT. CABIN RECIRC FAN FOUND TO HAVE INTERNAL DAMAGE. PLACARD PER MEL 21-00-43. C/BS J-8 J-9 J-10 PULLED AND COLLARED.