Inorganic fibres in the lung tissue of Hungarian and German lung cancer patients

Objective: To ascertain the lung burden of asbestos fibres in Hungarian lun g cancer patients in comparison with the cumulative asbestos exposure estim ated from the occupational history. Methods: For 25 Hungarian lung cancer p atients, lung tissue fibre analysis was performed by scanning transmission electron microscopy (STEM) and counting of ferruginous bodies (FBs) by ligh t microscopy. Cumulative asbestos exposure in fibre-years was assessed from a standardised occupational history using the report "fibre years" of the German Berufsgenossenschaften. Results: Median and maximum concentrations o f fibres longer 5 mum per gram dry lung tissue (g dry) were 0.03 and 7.38 m illion fibres/g dry for chrysotile, 0.00 and 0.21 million fibres/g dry for amphibole and 0.22 and 0.62 million fibres/g dry for other mineral fibres ( OMFs). The maximum values were observed in one patient for whom a high asbe stos exposure was evident in advance from the occupational history. Conclus ions: In comparison with reference values obtained by the same method for G erman patients with no indication of workplace asbestos exposure, increased concentrations of more than 0.2 million chrysotile fibres/g dry were obtai ned for six of the 25 Hungarian patients (24%). For one of them, the second highest estimate of a workplace exposure of 60 fibre-years and the highest tissue concentration of 7.38 million chrysotile fibres/g dry substantiate a high probability of a causal relationship to asbestos. A further comparis on can be made with the results for 66 German patients treated by surgical lung resection for a disorder other than mesothelioma, mainly lung cancer. For the Hungarian lung: cancer patients, similar amounts of chrysotile but distinctly lower amounts of amphibole fibres and distinctly higher amounts of OMFs were observed. A correlation between exposure estimates from occupa tional history and concentration of fibres in the lung tissue was observed for amphibole (Spearman: R = 0.66, P < 0.001, Pearson: R = 0.50, P = 0.01) and for chrysotile (Pearson: R = 0.48, P = 0.02).