Treatments affecting the rate of asbestos-induced mesotheliomas.

256 Wistar rats received a single injection into the right pleural cavity of UICC crocidolite in order to induce mesotheliomas. They were then given right intrapleural injectons of BCG, crystalline silica, talc, carrageenan or saline (as a control). There was no significant change in the mesothelioma rate in the rats exposed to BCG, silica or talc, but there was a 3-fold increase in mesothelioma incidence in the group injected with carrageenan.