Abstract
On the macroscopic examination of the mucous membrane of the pharynx and larynx of pupils of elementary and middle schools in the air polluted district, more significant increase of incidence of injection of the retropharyngeal wall, enlargement of the retropharyngeal lymphoid tissues, dilatation of vessels of the pharynx and injected swelling of the vocal cords, injection of the epiglottis and arytenoid area are found in the pupils of the elementary schools than in pupils of unpolluted districts.
Among the pupils of the middle schools is also a significant incidence of enlargement of the retropharyngeal lymphoid tissues and dilatation of vessels of the pharynx.
A further study will determine which group of pupils of the elementary schools and the middle schools are much more contaminated.
