What was found
DRUING DESCENT THROUGH 9000 FEET, DETECTED TOXIC FUMES, DONNED OXYGEN MASKS, MOST NOTICABLE THROUGH THE FRONT OF THE AIRCRAFT. COMPLIED WITH INFORMATION NOTICE 2017-T015A.(A) 1& 2. ENGS WERE RUN INDIVISDUALLY ISOLATING PACKS AND BLEED VALVES ONE AT A TIME. SAME PROCEDURE WAS DONE WITH APU. NON ABNORMAL CABIN ODOR NOTICED DURING ALL THIS PROCEDURES. AIRCRAFT IS OK FOR SERVICE.