Narrative:

While in cruise; the flight attendant (flight attendant)-a called and said that a passenger in first class thought they smelled smoke of some kind; but it was very faint. The flight attendant and other passengers could not smell the fumes at that time. Within about twenty minutes of the first report; a second passenger in first class said they thought they smelled something like what a gas leak in a house would smell like; but again was fairly faint. Flight attendant-a had another flight attendant come forward to verify the odor because she could still not detect anything. The other flight attendant said she could not smell anything; either. The first passenger then reported feeling nauseous; having hot flashes; and vomited. Several minutes later; a passenger in row 8 said they smelled a 'dirty socks' smell or something that smelled like sewage. At this time flight attendant-a had the other flight attendant come from the back of the aircraft to verify the smell. This time the aft flight attendant could smell a 'dirty socks' smell. When the captain and I heard 'dirty socks'; we immediately thought about a fume event and the captain ran the QRH for fumes in the cabin. About this time the flight attendant-a reported that her eyes and nose felt like they were getting irritated. After the QRH; procedure was complete and we had turned pack 1 off; the fumes subsided for the remainder of the flight. The captain followed the guidance in the fom and filled out the appropriate reports. The crew debriefed the event after the flight and a report was submitted. There was some engine work done on the number one engine before we left; apparently replacing a high pressure valve for turbine cooling and additionally adding engine oil to both engines. This may be coincidental but I don't know what other parts the mechanics had to remove to perform this procedure. This was particularly insidious as the smell was quite faint for a long time. Only one passenger smelled it and it seemed to be in conjunction with the ovens at first. The description of the smell was also hard to decipher and only one passenger thought they smelled it for quite a while with no corroboration.

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Original NASA ASRS Text

Title: A320 First Officer reported Flight Attendant and passengers experienced physiological symptoms due to fumes in the cabin.

Narrative: While in cruise; the FA (Flight Attendant)-A called and said that a passenger in first class thought they smelled smoke of some kind; but it was very faint. The flight attendant and other passengers could not smell the fumes at that time. Within about twenty minutes of the first report; a second passenger in first class said they thought they smelled something like what a gas leak in a house would smell like; but again was fairly faint. FA-A had another FA come forward to verify the odor because she could still not detect anything. The other FA said she could not smell anything; either. The first passenger then reported feeling nauseous; having hot flashes; and vomited. Several minutes later; a passenger in row 8 said they smelled a 'dirty socks' smell or something that smelled like sewage. At this time FA-A had the other FA come from the back of the aircraft to verify the smell. This time the aft FA could smell a 'dirty socks' smell. When the Captain and I heard 'dirty socks'; we immediately thought about a fume event and the Captain ran the QRH for Fumes in the cabin. About this time the FA-A reported that her eyes and nose felt like they were getting irritated. After the QRH; procedure was complete and we had turned PACK 1 off; the fumes subsided for the remainder of the flight. The Captain followed the guidance in the FOM and filled out the appropriate reports. The crew debriefed the event after the flight and a Report was submitted. There was some engine work done on the number one engine before we left; apparently replacing a high pressure valve for turbine cooling and additionally adding engine oil to both engines. This may be coincidental but I don't know what other parts the mechanics had to remove to perform this procedure. This was particularly insidious as the smell was quite faint for a long time. Only one passenger smelled it and it seemed to be in conjunction with the ovens at first. The description of the smell was also hard to decipher and only one passenger thought they smelled it for quite a while with no corroboration.

Data retrieved from NASA's ASRS site 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.