Experimental production of mesothelial tumours of the pleura by implantation of dusts in laboratory animals

IN view of the possible association between the development of mesotheliomas of the pleura and exposure to asbestos dust in people living in the Cape asbestos fields1,2, a preliminary experiment was undertaken to see if it was possible to produce mesotheliomas, in animals, by injecting various forms of asbestos into the pleural cavities. 110 young rats, mice, and guinea pigs were used. The experiment has not yet been concluded as 45 of the guinea pigs, and four of the rats, are still alive thirty months after the start of the experiment. This is a preliminary report of our positive findings in 106 rats which have either died or have been killed. © 1962 Nature Publishing Group.