The source of a foul-smelling odour in Sydney's south-west is under investigation after residents have complained that the recurring scent is giving them headaches. The smell has been reported in several residential streets in Revesby, Condell Park and towards Bankstown Hospital. READ MORE: Volunteer firefighter accused of deliberately starting blazesThe stench is being reported in several residential streets in Revesby and Condell Park. The Environment Protection Authority says it's up to Canterbury-Bankstown Council to act, stating the odour is linked to a Condell Park facility that is not licensed with the EPA. For now, council has asked residents to log dates and times they can smell the odour.