[The relation between the morphological stage of silicosis and the SiO2 content in hilar lymph nodes (author's...

There is a positive relation with significant differences in mean values between the severity of silicosis of hilar lymph noeds and their SiO2 contents. The average SiO2 values in silicosis I amount to 2.03 g %; in silicosis II: 2.86 g%, and in silicosis III: 3.89 g%. The average values in exposed miners without silicosis (= 1.70 g%) show no significant differences in comparison with those of silicose I cases and those of nonexposed male persons (= 0.82 g%). The results justify the attempt of a morphological classification of the severity of silicosis in the hilar lymph nodes encouraging the use of chemical examinations of dust for the evaluation of pneumoconioses, for instance, in the material of mediastinoscopies.