As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF, COCKPIT AND CABIN FILLED WITH SMOKE, DID NOT SMELL LIKE ELECTRICAL. FLIGHT RETURNED TO SEA. MAINT INSPECTED ENGINES INLETS AND EXHAUST APU AREA AND RAM AIR DOORS, NO DISCREPANCY FOUND. RAN APU WITH A/C PACKS AND ENGS WITH PACKS. SUSPECT ANTI-ICE FLUID FUMES CAUSED TROUBLE. ALL ELECT SYSTEMS OPERATED NORMAL AND ACFT RETURNED TO SERVICE.