In air pollution monitoring, numerous recent studies have indicated a direct relationship between particle size of airborne particulates and their harmful effects on the human respiratory system.
(numerous recent studies; have indicated; a direct relationship between particle size of airborne particulates and their harmful effects on the human respiratory system; L:In air pollution monitoring)
numerous recent studies
have indicated
a direct relationship between particle size of airborne particulates and their harmful effects on the human respiratory system L:In air pollution monitoring