Narrative:

The aircraft had significant ice and snow accumulation. At the deice pad; the deice crew used an unusually large amount of fluid to clear the contaminant. All checklists and procedures were completed in accordance with the CRJ200 manual. It was my takeoff on runway xxr. With good VMC we configured for a standard takeoff; flex thrust; flaps 8 degrees; engine bleeds open and APU off. Approximately 1 minute after takeoff; 'smoke toilet' EICAS message illuminated. All other EICAS indications were normal. I maintained control of the aircraft and took over communications while the first officer completed the non-normal checklist. First officer contacted flight attendant (first item on checklist). Flight attendant advised us that she could hear the smoke detector in the lavatory. However; she verified that there was no smoke or fire in the lavatory. She did mention a strange smell and mist in the aft cabin. I noticed the familiar smell of glycol. I believe she was not familiar with the smell of glycol because she was relatively new. While the first officer was working on the checklist; I advised tower that we needed to return for the smoke warning. ATC gave us vectors for a visual approach to runway zz. The first officer was in constant contact with the flight attendant during the flight. Her reports indicated that the mist and odor were dissipating as the flight progressed. We completed all normal checklists and landed without incident. After landing; I spoke to the flight attendant again to confirm the status of the cabin and passengers. She advised me that the cabin was clear and that none of the passengers required medical attention. We waved off crash fire rescue and continued to the gate. A discrepancy was entered into the log. I believe that glycol entered the bleed air system. The glycol was forced into the air conditioning system under high pressure (takeoff power) resulting in a smoke caution. I believe this occurred as a result of the large amount of glycol that was used to clear the aircraft of contaminants and using engine bleed air for the takeoff. Inform deice crews of this incident and stress the importance of avoiding 'no spray' areas. Consider revising post-deice checklist to enhance items that clear 10th stage bleed air system. It appears that this is a common problem in the crj-200. I have since learned of multiple similar incidents.

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Original NASA ASRS Text

Title: CRJ-200 flight crew requires deicing prior to departure then experiences toilet smoke EICAS one minute after takeoff. Glycol smoke is suspected and crew returns for uneventful landing.

Narrative: The aircraft had significant ice and snow accumulation. At the deice pad; the deice crew used an unusually large amount of fluid to clear the contaminant. All checklists and procedures were completed in accordance with the CRJ200 manual. It was my takeoff on Runway XXR. With good VMC we configured for a standard takeoff; flex thrust; flaps 8 degrees; engine bleeds open and APU off. Approximately 1 minute after takeoff; 'Smoke Toilet' EICAS message illuminated. All other EICAS indications were normal. I maintained control of the aircraft and took over communications while the First Officer completed the non-normal checklist. First Officer contacted Flight Attendant (first item on checklist). Flight Attendant advised us that she could hear the smoke detector in the lavatory. However; she verified that there was no smoke or fire in the lavatory. She did mention a strange smell and mist in the aft cabin. I noticed the familiar smell of glycol. I believe she was not familiar with the smell of glycol because she was relatively new. While the First Officer was working on the checklist; I advised Tower that we needed to return for the smoke warning. ATC gave us vectors for a visual approach to Runway ZZ. The First Officer was in constant contact with the Flight Attendant during the flight. Her reports indicated that the mist and odor were dissipating as the flight progressed. We completed all normal checklists and landed without incident. After landing; I spoke to the Flight Attendant again to confirm the status of the cabin and passengers. She advised me that the cabin was clear and that none of the passengers required medical attention. We waved off Crash Fire Rescue and continued to the gate. A discrepancy was entered into the log. I believe that glycol entered the bleed air system. The glycol was forced into the air conditioning system under high pressure (takeoff power) resulting in a smoke caution. I believe this occurred as a result of the large amount of glycol that was used to clear the aircraft of contaminants and using engine bleed air for the takeoff. Inform deice crews of this incident and stress the importance of avoiding 'no spray' areas. Consider revising post-deice checklist to enhance items that clear 10th stage bleed air system. It appears that this is a common problem in the CRJ-200. I have since learned of multiple similar incidents.

Data retrieved from NASA's ASRS site as of May 2009 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.