What was found
AFT FLIGHT ATTENDANT REPORTED FUMES AND A ELECTRICAL SMELL IN THE CABIN. PASSENGERS WERE COMPLAINING ABOUT THEIR EYES BURNING. THE CAPTAIN MADE THE DECISION TO RETURN TO FIELD. THEY DECLARED AN EMERGENCY WITH ATC. FIRETRUCKS MET THE AIRCRAFT ON THE ARRIVAL BACK IN BUT WERE NOT NEEDED. THERE WAS ALSO NO INJURIES TO PASSENGERS OR CREW MEMBERS. / REMOVED AND REPLACED LH ACM IAW CRJ 900 AMM 21-51-08-000/400-801-A01. OPS CHECKS GOOD. LEAK CHECK GOOD. NO MORE SMELL OF EYE BURNING NOTED AT THIS TIME.