Black lungs in the general population: a new look at an old dispute.

Almost from the time that autopsies were first routinely carried out, darkening of lungs with increasing age was described. Different explanations for the origin of the accumulating black pigment arose and by the early nineteenth century three hypotheses had emerged: 1) soot inhaled into the lungs from the air; 2) carbon accumulating in the lungs from abnormal pulmonary carbon dioxide metabolism; and, 3) pigment derived from the blood. In 1813 the English physician and chemist George Pearson published a paper in which he described the recovery of the black pigment from lungs and its chemical analysis. Pearson declared the black pigment to be airborne carbon/soot from the burning of coal and wood. He described these particles depositing in 'black spots' in the terminal airways and accumulating in the peribronchial lymph nodes, forming 'black glands'. Despite Pearson's prescient account, debate continued and the true explanation, given in that paper, was not fully accepted until the late nineteenth century.

Deposits in the lungs of Kwäday Dän Ts'ìnchi man: Characterization by a combination of analytical microscopical methods.

OBJECTIVES: The approximately 250 years old remains of the Kwäday Dän Ts'ìnchi man were found in a glacier in Canada. Studying the state of preservation of the corpse, we observed black deposits in his lung. Following this observation we wanted to determine: (1) location of the deposits in the lung tissue, (2) composition and origins of the deposits. METHODS: By light microscopy (LM) and transmission electron microscopy (TEM), we studied the deposits in the Kwäday Dän Ts'ìnchi man' s lung and compared it with distribution of anthracotic deposits in contemporary samples from the David Harwick Pathology Centre (DHPC). To determine chemical composition of the inclusions we used Raman spectroscopy. Scanning electron microscopy and elemental mapping was used for determine the chemical elements. RESULTS: The histopathological identification of anthracosis in the Kwäday Dän Ts'ìnchi man's lung allowed us to distinguish crushed parenchyma from conducting airway tissue and identification of particles using LM and TEM. Crystal particles were found using TEM. Ordered carbonaceous material (graphene and graphite), disordered carbonaceous material (soot) and what might be minerals (likely conglomerates) were found with Raman spectrometry. Gold and lead particles in the lung were discovered with scanning electron microscopy and elemental mapping. CONCLUSIONS: Presence of soot particles in anthracotic areas in the Kwäday Dän Ts'ìnchi man's lung probably were due to an inhalation of particles in open fires. Gold and lead particles are most likely of an environmental origin and may have been inhaled and could have impacted his health and his Champagne and Aishihik First Nations (CAFN) contemporaries.

James Craufurd Gregory, 19th century Scottish physicians, and the link between occupation as a coal miner and lung disease.

By the mid-19th century about 200,000 miners were employed in a UK coal mining industry still growing with the advances of the Industrial Revolution. Coal miners were long known to suffer poor health but the link to inhaling dust in the mines had not been made. In 1813 George Pearson was the first to suggest that darkening of lungs seen in normal individuals as they aged was caused by inhaled soot from burning oil, candles and coal, which were the common domestic sources of heat and light. In 1831 Dr James Craufurd Gregory first described black pigmentation and disease in the lungs of a deceased coal miner and linked this to pulmonary accumulation of coal mine dust. Gregory hypothesised that the black material seen at autopsy in the collier's lungs was inhaled coal dust and this was confirmed by chemical analysis carried out by Professor Sir Robert Christison. Gregory suggested that coal dust was the cause of the disease and warned physicians in mining areas to be vigilant for the disease. This first description of what came to be known as 'coal worker's pneumoconiosis' sparked a remarkable intellectual effort by physicians in Scotland, culminating in a large body of published work that led to the first understandings of this disease and its link to coalblackened lungs. This paper sets out the history of the role of Scottish physicians in gaining this understanding of coal worker's pneumoconiosis. It describes Gregory's case and the lung - recently discovered in the pathology collection of the Surgeons' Hall Museums, Edinburgh, where it has lain unnoticed for over 180 years - on which Gregory based his landmark paper.

The influence of dust standards on the prevalence and severity of coal worker's pneumoconiosis at autopsy in the United States of America.

CONTEXT: Coal worker's pneumoconiosis is a major occupational lung disease in the United States. The disease is primarily controlled through reducing dust exposure in coal mines using technological improvements and through the establishment of dust standards by regulatory means. OBJECTIVE: To determine if dust standards established in the US Federal Coal Mine Health and Safety Act of 1969 have reduced the prevalence and severity of coal worker's pneumoconiosis. DESIGN: The study population included materials from 6103 deceased coal miners submitted to the National Coal Workers' Autopsy Study from 1971 through 1996. Type and severity of coal worker's pneumoconiosis were classified using standardized diagnostic criteria. RESULTS: Among miners who worked exclusively prior to the 1969 dust standard, 82.6% had coal macules, 46.3% coal nodules, 28.2% silicotic nodules, and 10.3% progressive massive fibrosis. Lower prevalences were noted among miners exposed exclusively to post-1970 dust levels: 58.8% had coal macules, 15.0% coal nodules, 8.0% silicotic nodules, and 1.2% progressive massive fibrosis. The differences in prevalence were highly significant (P < .001) for all types of pneumoconiosis, including progressive massive fibrosis, after adjustment for age, years of mining, and smoking status. CONCLUSIONS: The study confirms a beneficial impact of the first 25 years of the dust standard established by the 1969 act on the prevalence and severity of coal worker's pneumoconiosis in US coal miners. However, pneumoconiosis continues to occur among miners who have worked entirely within the contemporary standard, suggesting a need for further reductions in exposure to respirable coal mine dust.

Beyond a shadow of a doubt? Experts, lay knowledge, and the role of radiography in the diagnosis of silicosis in Britain, c. 1919-1945.

The history of silicosis provides an important chapter in the history of occupational and environmental health. Recent historical scholarship has drawn attention to the importance of patient attitudes, popular protests, and compensation claims in the formation of a "lay epidemiology" of such a disease, frequently challenging the scientific orthodoxies devised by large corporations and medical specialists. Surprisingly little research has been undertaken on the United Kingdom, which provided much of the early expertise and medical research in respiratory diseases among industrial workers. This article examines the introduction of a particular technique, x-radiography, and its use by radiologists and others in debates on the causes and consequences of silica inhalation by the laboring population in Britain during the early decades of the twentieth century. In contrast to some recent interpretations, and also to the narrative of progress that practitioner historians have developed since the 1940s, this article suggests that the use of this technology was contested for much of this period and the interpretation of X-rays remained disputed and uncertain into the 1950s. The article also questions recent accounts of lay epidemiology as an adequate model for understanding the progress of such innovations in medical history.