If your mucus is gray or black... …you likely inhaled dark-colored particles, like smoke from a fire or heavy exhaust. Regular smokers can also blow out darker mucus because of the tar or other toxic ...
Mercola, you should seek medical attention: If your symptoms persist for more than 10 days If you experience difficulty breathing, develop a severe cough, notice thick green or yellow mucus ...
Green mucus results from an intensified immune response. The green tint comes from an enzyme called myeloperoxidase, which is produced by neutrophils (a type of white blood cell). This enzyme ...