As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOTH AFT LAV SMOKE DETECTORS WENT OFF AFTER TAKEOFF FOR BUF BOTH ENG ANTI-ICE ON FOR TAKEOFF, NO SMOKE, SLIGHT ODOR DETECTED, DISSIPATED RAPIDLY. SUSPECT DE-ICE FLUID INGESTION. APU INLET CLEAN PERFORMED ALT DUCT BURNOUT PER AIJC OPN 5090 AND REPLACED WATER SEPARATOR BAGS PER AIJC 7904. ALL CHECKS GOOD.