Effect of choline and mineral fibres (chrysotile asbestos) on guinea-pigs

Both short-term and long-term, low and high doses of parenterally administered choline produce pathological lesions in lungs and lymph-nodes of rats and guinea-pigs. Male guinea-pigs given choline by intraperitoneal injection, 40 doses of 50 mg of choline chloride, 5 days per week for 8 weeks, developed lung lesions consisting of peripheral nodules of small cells, neoplastic bronchiolar epithelium, carcinomatous lesions and changes in the pleural surface by the end of the experiment (680 days). In a second group, a single intraperitoneal injection of 15 mg of chrysotile asbestos given after 210 days of choline administration resulted in the early onset of pulmonary lesions at 570 days but there was, in addition, evidence of enhancement of cancerous lesions both in lung and in lymph-nodes at 570 days and 680 days as compared with choline alone. It is clear from the present experiment that the parenteral administration of carcinogenic mineral fibres (chrysotile asbestos) and availability of excess choline act synergistically in producing cancerous lesions in lungs and other organs.