Large or coarse particulates are between 10 and 2.5 micrometers in diameter. Particulates of this type are found commonly near dusty roadways and industrial areas. Particulate matter pollution can cause respiratory illness as well as impair atmospheric clearness. Information source: U.S. EPA.
Large particulates, although generally less harmful than small particulates, can cause throat and airway irritation, coughing, decreased lung function, aggravated asthma, and the development of chronic bronchitis. Information source: U.S. EPA.