Variations in the Histological Patterns of the Lesions of Coal Workers' Pneumoconiosis in Britain and Their Relationship to Lung Dust Content^1,2

Abstract

The lungs of 490 British coal miners were examined for comparisons of the lesions of coal workers' pneumoconiosis with lung dust content and dust exposure. Variations were found in histological appearances that formed a range, the extremes of which indicated two separate patterns of disease. In men from high rank collieries, whose lung dust had a high carbon content and little ash, most of the nodules of simple pneumoconiosis were evenly pigmented with dust, and where progressive massive fibrosis (lesions greater than 1 cm in diameter) had developed, this appeared to be by the enlargement of a single lesion. In men from low rank collieries where the ash content of lung dust was high, the centers of the nodules were often free of dust particles and in extreme cases these lesions were very similar to silicotic nodules. If PMF developed in these cases, it often appeared to be by the fusion of closely spaced groups of smaller nodules. While there appeared to be little difference between the lung dust composition of men from high rank collieries and the dust to which they had been exposed, in men from low rank collieries the proportion of the noncoal minerals in the lungs was usually higher than it had been in the mine dust. This indicated some form of differential retention of these components, which was progressively more marked in men with the more serious grades of pneumoconiosis.

Factors associated with the development of progressive massive fibrosis in British coalminers: a case-control study.

“…This pattern, especially when considered in conjunction with the results on quartz and kaolin plus mica concentrations and on particle size, enhances the impression of the distinctive nature of PMF in high rank collieries. 33 Finally, analyses at low and medium rank collieries highlighted breathlessness as the symptom most strongly associated with PMF, with more than a twofold increase in relative risk, highly significant statistically, after matching and adjustment for age and exposure. We have been unable to find an obvious explanation of this association; one possibility is that men who complain of breathlessness may, for a given dust exposure, inhale and retain a greater dose of dust because of differences in breathing pattern.…”

Progression of Pneumoconiosis in Coal Miners after Cessation of Dust Exposure: A Longitudinal Study Based on Periodic Chest X-ray Examinations in Hokkaido, Japan

“…Most studies on the development of CWP were reported in the U.K. (1)(2)(3)(4)(5)(6), and such studies on pneumoconiosis/silicosis in workers other than coal miners have also been reported in sandblasters (7,8), in pencil slate workers (9), iron-ore miners (10), granite miners (11,12), and so on (13)(14)(15). Without the newly additional dust exposure effects, we have declared that the progression of pneumoconiosis was observed even after retirement from coal mining.…”

Selenium and exposure to fibrogenic mineral dust: A mini-review

“…Radiographic appearance allows classifying CWP into simple pneumoconiosis and progressive massive fibrosis. Simple CWP is characterized by small rounded lung opacities in the upper zones of both lungs, while progressive massive fibrosis features large conglomerate lung opacities (Davis et al, 1983;Soutar and Collins, 1984;Young et al, 1992). Two types of coal mining exist, surface coal mining and underground coal mining.…”