B737-800
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 2
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Illness / Injury; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Diverted; Flight Crew Overcame Equipment Problem; General Physical Injury / Incapacitation
Aircraft
At cruise; aft flight attendants complained of fumes near aft galley that smelled like burning plastic or electrical fire. No smoke was observed. No passengers complained. The two forward flight attendants went back and confirmed the smell; but were not exposed very long. The two aft flight attendants were exposed longer and complained of throat and chest pain. We elected to turn around and divert to ZZZ. The two aft flight attendants were taken for medical care. No one else was affected. On ground in ZZZ; passengers disembarked. ARFF personnel scanned the aft galley area with thermal imaging equipment and noticed nothing overheating. A mechanic searched the aft galley area and smelled nothing with the packs off; but did notice smell when right pack was turned on. Apparently something wrong in right pack causing fumes.
B737-800 Captain reported medical diversion after being notified by flight attendants of 'burning plastic/electrical fire' odor causing physiological issues. Two flight attendants received medical treatment.