Prevalence and Pathogenesis of Pneumoconiosis in Coal Workers

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The National Institute of Environmental Health Sciences (NIEHS) and Brogan & Partners are collaborating with JSTOR to digitize, preserve and extend access to Environmental Health Perspectives.Dust dose and composition do not appear to account wholly for changes in the prevalence of coal workers' pneumoconiosis in Europe. In certain coal pits high progression evidently occurred with relatively low dust exposure or vice versa, whereas progression in relation to dust levels might be variable. Exceptionally high quarts concentrations occur in coal mine dust when pneumoconiosis may progress with unusual rapidity. Under such circumstances lesions resembling silicotic nodules may be found, but with the customarily lower levels of quart the pathological features assume the form characteristic of coal workers. Morphological changes in relation to dust content of human and animal lungs, as well as cellular behavior, have not accounted completely for the epidemiological findings. Considering all the pathological evidence helps explain the pathogenesis of pneumoconiosis and vagaries of progression. The origin of progressive massive fibrosis cannot be explained simply in terms of dust burden or immunological features, and the role of an infective factor cannot be dismissed. Moreover, lipid secretion by alveolar epithelium introduces a new element that could affect the development of simple and complicated pneumoconiosis. In vitro, cytotoxicity appeared to be too variable for predictive purposes, though direct assay of fibrogenicity using the macrophage fibrogenic factor suggested that dust dose was more important than dust composition. Assessing individual susceptibility presents serious obstacles.

Airways obstruction, coal mining, and disability.

“…This was shown by Gough and Heppleston many years ago,'7 18 and has subsequently been confirmed by the US Public Health Service studies which showed that simple CWP in nonsmokers was associated with an increase in the residual volume and total lung capacity and in some instances with a slight to moderate loss of elastic recoil. '920 Furthermore, Hankinson and colleagues, who were working in the Appalachian Laboratory for Occupational Lung Disease (ALFORD) at the same time showed that simple CWP was associated with an increase in air space size.2' These workers were, however, unable to demonstrate that the increased size was associated with a reduction in ventilatory capacity.…”

From Quartz Hazard to Quartz Risk: the Coal Mines Revisited

“…A basic comment on our approach would also be that, although mechanisms of quartz-and coal dustinduced fibrosis are similar, distinct pathological differences are present between simple pneumoconiosis and silicosis (Heppleston, 1988). However, it is unknown whether this difference is relevant to the total lung burden of quartz and its relevance to this risk assessment procedure.…”

“…Epidemiological studies in coal miners have indicated that the risk of dust-related disease is subject to considerable variation. The incidence of sCWP and PMF varies with countries, regions and even within horizons of mine pits (Reisner et al, 1985;Heppleston, 1988;Gautrin et al, 1994). German epidemiological studies showed that the risk of contracting sCWP between coal fields varied between 2 and 40%, although miners had comparable levels of exposure (for a review see Morfeld and Piekarski, 1998).…”

“…Similarly, we know that coal itself can cause pneumoconiosis (Collis and Gilchrist, 1928) and that coal rank (determined by coal quality) does affect the retained lung burden (Douglas et al, 1986) and is involved in the progression of pneumoconiosis (Walton et al, 1977). In addition, the incidence of simple coal workers' pneumoconiosis (sCWP) and progressive massive fibrosis (PMF) at given quartz exposures varies with countries, regions and even within horizons of mine pits (Reisner et al, 1985;Heppleston, 1988;Gautrin et al, 1994).…”

Estimating mortality from coal workers' pneumoconiosis among Medicare beneficiaries with pneumoconiosis using binary regressions for spatially sparse data

“…In Equation (1), π ij represents the risk of death from pneumoconiosis for the i th person residing in the j th county, which is explained by a set of individual and county‐level characteristics X i , and Z j , county‐specific random effects ν j , and individual random effects ε ij . We imposed zero mean identical and independent Gaussian distribution with variance σ 2 on ε ij . We considered three different models.…”