Autopsy study of coalminers’ lungs. Final report on CEC Contract 6244-00/8/103

This report is based on the examination of lungs from 500 coalminers who had. worked in 25 collieries that were involved in the British National Coal Board’s Pneumoconiosis Field Research Study. These collieries were chosen from all the mining areas in the United Kingdom.The study group of 500 cases is not typical of all miners involved in Pneumoconiosis Field Research being biased in favour of selection of older men with established pneumoconiosis. For each set of lungs detailed estimations were made on the number and types of dust lesion or areas of emphysema and the dust content of one lung was extracted for mineralogical analyses. For the purpose of this report the cases were classified into three pathological types based on macroscopic examination: those with only soft dust macules (M) , those with in addition ore or more palpable small fibrotic nodules (F) and cases with nodules larger than 1 cm (PMF). Pathological findings were compared with the lung dust content at death as well as lifetime estimates of dust exposure. In addition chest radiographs taken shortly before death, where these were available were compared to the types of pathology found at autopsy as well as to the lung dust content. The main conclusions from each group of studies are presented in three chapters and may be summarised as follows:-A comparison of pathological types of pneumoconiosis found at autopsy with lung dust content and lifetime dust ex-nosureFor the whole group of cases the mean weights of all types of mineral dust present in the lungs increased between the pathologicaltypes M, F and PMF although there was considerable variation withineach category.When the collieries were divided into six groups defined by the rank of coal mined it was found that in cases from all rank groups the mean lung weights of each mineral increased between the three pathological types but the level of increase varied considerably. For cases with either macules or fibrotic nodules the total dust did not differ significantly between the rank groups. For cases with PMF, however, those from the highest rank group contained significantly more dust than those cases from other rank groups.