Rarity of mineral fibre pleurisy among persons exposed to Finnish anthophyllite and with low risk of mesothelioma.

Abstract

Endemic pleural plaques are reported from many parts of the world. In Central Europe and in Finland no connection with malignant mesotheliomas has been found, whereas this tumour is often encountered in areas in Turkey where endemic plaques also occur. There seem, however, to be differences in the radiological appearances found in these areas. In the present study chest radiographs of 317 persons with pleural plaques from the endemic area of Finland were scrutinised. It was found that 4-7% showed a blunted costophrenic angle unilaterally and 0-9% bilaterally. The prevalence of sequelae of pleurisy is statistically very highly significantly lower than in people with pleural plaques in Turkey. As the risk of mesothelioma appears to be low in Finland, the results are in accordance with the hypothesis that the risk of mesothelioma in a given population is higher if in that population there is a high incidence of benign asbestos pleurisy.The endemic occurrence of pleural plaques was first described from Finland' and has since been reported from many parts of the world.2 Various mineral fibres in the ground have been identified as the probable cause. Interestingly, Finnish and Central European endemic plaques seem to have no connection with the occurrence of malignant pleural mesothelioma,3 whereas those in Turkey are associated with a sometimes very high risk of development of this otherwise rare tumour.4 A study in Turkey indicated that among populations with a high risk of mesothelioma there was a high incidence of sequelae of pleurisy, presumed to be related to asbestos.5 Comprehensive reports of the frequency of mesothelioma among persons with nonoccupational pleural plaques in Finland are still lacking but available data indicate that the prevalence is lower than in the mineral fibre areas of Turkey, and

Computed tomography of asbestos-related pleural abnormalities

“…A study of a Finnish, male, urban, necropsy population aged 33 to 69 years showed plaques in 58% (Karjalainen et al 1994). Previously, plaques were reported in 52% of the necropsies of urban dwellers and 32% of those who had lived in the countryside in Finland (Hillerdal et al 1984). A high prevalence of pleural plaques has also been reported in Japan (Hiraoka et al 1993).…”

Anthophyllite Asbestos: The Role of Fiber Width in Mesothelioma Induction Part 1: Epidemiological Studies of Finnish Anthophyllite Asbestos

“…reckoned the average fibre concentration was still 50 fibres/ml in the late 1960s. Not surprisingly, as Hillerdal et al (1984) Various points emphasized the horrific dust conditions. Thus, Prof. Huuskonen translated the film that noted at the time of filming a total number of around 40 houses built mainly in the 1940s and 50s.…”

Radiographic abnormalities among Finnish construction, shipyard and asbestos industry workers

“…The Paakkila anthophyllite mine was in operation between 191 8 and 1976, and thus about 40% of all asbestos used in Finland has been amphibole. The high prevalence of pleural abnormalities in Finland and in the present survey is not surprising (2,3,23), because anthophyllite is one of the most aggressive asbestos fibers to induce pleural plaques (25). In terms of use and exposure, chrysotile was the most widespread type in the construction and asbestos cement industry.…”