Narrative:

We received a call from business class galley flight attendants (fas) reporting that she was feeling light headed and dizzy. 10 minutes later all 3 fas in the business class galley called to report light headedness; difficulty breathing; and slight headache. Recirc fans were turned off to increase fresh air to cabin. Only those 3 fwd fas were affected; the 3 working in coach were not. Symptoms went away within a few minutes. Approximately 10 minutes after that a 4th flight attendant who had come fwd to assist in the business class section called to report that he too now had a headache. Contact made with dispatch; [medical services]; and [maintenance] at this point. While conversing with dispatch we received another call from fwd galley to report all 4 of them now had all previous symptoms return. Decision to descend and divert was made at that point. Made immediate descent to FL240 to further lower cabin altitude and original plan was [a] diversion. After level at FL240 for 10 minutes purser called to inform us that all symptoms had gone away. I also had them use portable O2 starting just prior to descent. At that point decision was made in conjunction with dispatch to continue to ZZZ. Upon arrival we were met by emergency medical personnel who checked all crew members vitals. At no point during the time that the fas were showing symptoms did either of us in the cockpit feel any of the same symptoms. I had the relief pilot check them and several passengers to see if they were ok. Problem seemed to be located in the fwd galley only. We did have a shipment in the fwd cargo compartment which contained 44 lbs of dry ice which the emergency crews were notified about. After arrival police also met the aircraft and wanted statements from all of us. I refused for us and recommended the same to the fas.

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Original NASA ASRS Text

Title: A B767 returned to the departure airport after the business class flight attendants became light headed. Coach flight attendants were unaffected. Forty four pounds of dry ice were in the forward cargo hold.

Narrative: We received a call from Business Class galley Flight Attendants (FAs) reporting that she was feeling light headed and dizzy. 10 minutes later all 3 FAs in the Business Class galley called to report light headedness; difficulty breathing; and slight headache. Recirc fans were turned off to increase fresh air to cabin. Only those 3 fwd FAs were affected; the 3 working in Coach were not. Symptoms went away within a few minutes. Approximately 10 minutes after that a 4th FA who had come fwd to assist in the Business class section called to report that he too now had a headache. Contact made with Dispatch; [medical services]; and [maintenance] at this point. While conversing with Dispatch we received another call from fwd galley to report all 4 of them now had all previous symptoms return. Decision to descend and divert was made at that point. Made immediate descent to FL240 to further lower cabin altitude and original plan was [a] diversion. After level at FL240 for 10 minutes Purser called to inform us that all symptoms had gone away. I also had them use portable O2 starting just prior to descent. At that point decision was made in conjunction with Dispatch to continue to ZZZ. Upon arrival we were met by emergency medical personnel who checked all crew members vitals. At no point during the time that the FAs were showing symptoms did either of us in the cockpit feel any of the same symptoms. I had the relief pilot check them and several passengers to see if they were ok. Problem seemed to be located in the fwd galley only. We did have a shipment in the fwd cargo compartment which contained 44 lbs of dry ice which the emergency crews were notified about. After arrival police also met the aircraft and wanted statements from all of us. I refused for us and recommended the same to the FAs.

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.