Reaction of cells cultured in vitro to different asbestos dusts of equal surface area but different fibre length.

Peritoneal macrophages from mice were cultured in Leighton tubes and exposed to UICC chrysotile, crocidolite or amosite. Their cytotoxicity (Erythrosin uptake), release of lactate dehydrogenase (LDH) and uptake of 3H amino acids were determined according to weight (100 micrograms/tube), surface area (21.3 cm2 or fibre length. In all reactions tested chrysotile was more active than the amphiboles, but the latter gained activity if applied according to surface area. Uptake of 3H amino acids basis. Long-fibred asbestos dusts proved more cytotoxic than the corresponding short fibres when used on the basis of equal mass. In experiments with ascites tumour cells induced by nemalite the different asbestos dusts showed a very significant reduction of 3H-labelled thymidine uptake, but on weight basis the amphibole uptake was markedly higher.