What was found
STRONG BURNING ODOR SMELL OF PLASTIC IN CABIN ON CLIMB OUT. COULD SMELL IT IN COCKPIT. DECLARED EMERGENCY, LANDED WITHOUT INCIDENT. PERFORMED HIGH POWER RUN OF ENGINE 1 AND 2, FOUND ODOR COMING FROM ONLY BLEED 2. PERFORMED COMPRESSOR BORESCOPE, NO DEFECTS NOTED. R&R BOTH RECIRCULATION FILTERS.