I have a lot of sputum and at times it is hard thick chunks. I have copd, lung cancer and because of my extreme cough and so much sputum they ran sputum tests for bacterial and fungal. I have something called mycobacterium abscessus. It is something that people with other respiratory issues can get from soil, water, medical equipment. It is a non- tuberculosis non contagious infection in your lungs. There are many species of this. It is very difficult to treat and treatment can last for more than a year and very difficult to cure. You have to be treated with3-4 toxic antibiotics for long periods of time. Look up NTM infections and MAC lung disease infections. Not saying you have any of this but it may be worth getting your Dr to run sputum tests. Even with lung cancer and copd I never had the symptoms I do now until I got this mycobacterium infection. I have a lot more shortness of breath, wheezing, and sputum than I did before this awful infection