Due to a certain defect in the airconditioning air duct, the humidity builds up to a high level causing eventual mold formation in the air duct. As a result of that a bad smell will progressively increase untill it can be easily noticable especially during the first minute of starting the air conditionner. Molds are known to be strong allergens and can result in worsening nasal allergy symptoms, cough, nasal congestion, and sneezing. I belleive it is a health hazard to people with mold allergies like my son who had noticable wosening of his nasal congestion and eventually his obstructive sleep apnea symptoms as a result of that. Up on cantacting the local dealer in teh area and later the BMW customer service department, they acknowledged the problem since I was not the only one with the same complaint, but they only offered to clean the ducts once a year, which is a short term remedy and does not prevent the recurrence of the problem. I beleive it is a haelth risk and customers need to be informed upfront about this problem before they make a selection to buy that vehicle.

- Louisville, KY, USA