You are right to be concerned about the blood in your boyfriend’s sputum. Coughing up blood is definitely abnormal, under any circumstance. Given his age and long smoking history, the blood was probably due to his having chronic bronchitis. If so, that would be serious now and, even more so, later in life. This blood should be considered serious and, at a minimum, he should see his doctor and have a chest x-ray.
hi sorry not got a lot of advice for you but i would make an apointment for him to see the doctor and take a sample of the thick mucus and get it analized and go from there hope he gets it sorted out good luck