I have had a cronic cough for about the last 4 years now. I was diagnosed with asthma, and am currently on advair, and a sinus infection with nasal pollups, they did surgery to remove the nasal pollups, and I am still stuck with a runny nose six months later, and the cough hasn't gotten any better. I have been coughing up long string like mucus yellow/dark yellow in color for the psat year now. I have had an allergy test about a year ago and chest x-rays, but everything came back negative. i did smoke but haven't for some time now. I work in the industrial construction industry, and have minor exposure to asbestos. I am 29 years old, 5'-6" ad 150 lbs,Any idea?