As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 2 JFK-BUF, AIR RETURN TO JFK DUE TO DURING TAKEOFF ROLL SLIGHT ODOR DETECTED, CONTINUED THROUGH INITIAL CLIMBOUT. NO INDICATIONS OF SMOKE OR HAZE. CABIN REPORTED SLIGHT ODOR TOO. QRH FOLLOWED AND PACKS WERE TURNED OFF, ODOR DISSIPATED. PERFORMED FIM 21-20-00-801A FOUND RIGHT ACM NR 2 PACK CONTAMINATED. REMOVED AND REPLACED RIGHT ACM IAW AMM 21-51-05. OPS CHECK GOOD.