Narrative:

During takeoff, noticed odor in cockpit which seemed to dissipate at thrust reduction with first flap retraction. Copilot reported he could still detect odor. During climb out over interphone questioned flight attendants. They reported that the odor was noticed, but seemed to be dissipating. 1 flight attendant reported that a plastic cup had melted against a hot plate in the mid galley. Flight attendant that worked mid cabin galley reported to me that there was no burning or melting plastic in the mid galley, that previous report of melting plastic was in error. During the troubleshooting procedure and in radio contact with maintenance, we turned off the left pack and the trim air switch. The odor in the cabin seemed to dissipate. The copilot reported that he still detected some odor. Left pack was turned on and an immediate increase in odor was noted. Left pack turned off and decision to return to and overweight landing was made. After landing, it was thought that air carrier turbo 2380 poly oil ester had entered the pneumatic stream from the left engine (first flight after left engine change). When heated or inhaled, the oil causes headache, nausea, and increased pulse rate. Also causes confusion. The paramedic stated that it causes a narcotic effect, though company medical says that that is an overstatement of the effect, that it is benign having little effect. The effects did leave after 12 hours as stated by medical.

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Original NASA ASRS Text

Title: A B757-200 IN CLB AT 17000 FT DIVERTED DUE TO FUMES FROM THE L AIR CONDITIONING PACK CAUSED BY RESIDUAL OIL IN NEWLY REPLACED L ENG.

Narrative: DURING TKOF, NOTICED ODOR IN COCKPIT WHICH SEEMED TO DISSIPATE AT THRUST REDUCTION WITH FIRST FLAP RETRACTION. COPLT RPTED HE COULD STILL DETECT ODOR. DURING CLBOUT OVER INTERPHONE QUESTIONED FLT ATTENDANTS. THEY RPTED THAT THE ODOR WAS NOTICED, BUT SEEMED TO BE DISSIPATING. 1 FLT ATTENDANT RPTED THAT A PLASTIC CUP HAD MELTED AGAINST A HOT PLATE IN THE MID GALLEY. FLT ATTENDANT THAT WORKED MID CABIN GALLEY RPTED TO ME THAT THERE WAS NO BURNING OR MELTING PLASTIC IN THE MID GALLEY, THAT PREVIOUS RPT OF MELTING PLASTIC WAS IN ERROR. DURING THE TROUBLESHOOTING PROC AND IN RADIO CONTACT WITH MAINT, WE TURNED OFF THE L PACK AND THE TRIM AIR SWITCH. THE ODOR IN THE CABIN SEEMED TO DISSIPATE. THE COPLT RPTED THAT HE STILL DETECTED SOME ODOR. L PACK WAS TURNED ON AND AN IMMEDIATE INCREASE IN ODOR WAS NOTED. L PACK TURNED OFF AND DECISION TO RETURN TO AND OVERWT LNDG WAS MADE. AFTER LNDG, IT WAS THOUGHT THAT ACR TURBO 2380 POLY OIL ESTER HAD ENTERED THE PNEUMATIC STREAM FROM THE L ENG (FIRST FLT AFTER L ENG CHANGE). WHEN HEATED OR INHALED, THE OIL CAUSES HEADACHE, NAUSEA, AND INCREASED PULSE RATE. ALSO CAUSES CONFUSION. THE PARAMEDIC STATED THAT IT CAUSES A NARCOTIC EFFECT, THOUGH COMPANY MEDICAL SAYS THAT THAT IS AN OVERSTATEMENT OF THE EFFECT, THAT IT IS BENIGN HAVING LITTLE EFFECT. THE EFFECTS DID LEAVE AFTER 12 HRS AS STATED BY MEDICAL.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.