[Determination of dust content in the lungs of 10 cases with stage I coal workers' pneumoconiosis (CWP)].

Dust deposition in the lung tissue of 10 cases with pathologically diagnosed stage I CWP was determined. The left lung tissue was digested by 37% hydrochloric acid, and its organic composition was removed by chloroform and 50% ethanol. Results showed total dust content averaged 8.64 grams per left lung, with a standard deviation of 5.54 grams. Dust content varied in different parts of the lung, measured the highest in lymph nodes, the upper lobe and pleura the next and the lowest in the lower lobe, with a very significant difference by ANOVA (F = 44.76, P < 0.001). Dust less than 5 microns in diameter accounted for 94.0% of the total content, and that equal to or more than 10 microns only 0.8%. A certain amount of fibrous dust could be found in the lung. Dust deposited in the lung accounted only for 0.64% of that exposed to.