Fiber concentration in lung tissue of patients with malignant mesothelioma. A case-control study.
The risk of malignant mesothelioma associated with low-level asbestos exposure is an important unresolved issue today. We have analyzed the asbestos fiber concentration in lung tissue from 14 cases of malignant mesothelioma and 28 case-matched controls by scanning electron microscopy. The cases represent 86% of all mesotheliomas recorded by the Cancer Registry of Norway from the county of Hordaland between 1970 and 1979. Based on 1 million fibers per g of dried tissue as an indicator of cumulated asbestos exposure, the odds ratio (relative risk) was 8.5 (95% confidence limits, 2.3-31.1). Assuming that the risk of malignant mesothelioma is related to mineral fiber concentration in lung tissue, it is concluded that a fiber concentration exceeding 1 million fibers per g of dried tissue is associated with an increased risk of malignant mesothelioma. Furthermore, the results are consistent with a no-threshold response.
D000328:Adult; D000368:Aged; D001194:Asbestos / Q000009:adverse effects* / Q000032:analysis; D005260:Female; D006801:Humans; D008168:Lung / Q000032:analysis*; D008297:Male; D008654:Mesothelioma / Q000209:etiology* / Q000378:metabolism; D008875:Middle Aged; D009664:Norway; D009784:Occupational Diseases / Q000209:etiology* / Q000378:metabolism; D010997:Pleural Neoplasms / Q000209:etiology* / Q000378:metabolism; D011336:Probability; D012306:Risk
D001194:Asbestos