Predisposing conditions include Inadvertent injury to the canal caused by cleaning with cotton swabs or other objects Allergies Psoriasis Eczema Seborrheic dermatitis Decreased canal acidity (possibly due to the repeated presence of water) Irritants (eg, hair spray, hair dye) Attempts to clean the ear canal with cotton swabs can cause microabrasions of the delicate skin of the ear canal (these microabrasions act as portals of entry for bacteria) and may push debris and cerumen deeper into the canal.