Sarcomas Induced in Rodents by Imbedding Various Plastic Films.

Sarcomas have been produced in rats by imbedding subcutaneously various plastic films, namely cellophane, an alcohol-extracted cellophane, a commercial polyethylene, a very pure polyethylene and vinyl chloride film. 2. Sarcomas have been produced in mice, but in a lesser percentage of cases, by imbedding cellophane and pure polyethylene film. 3. Apparently impurities and additives in the films do not account for the production of these malignant tumors. 4. So far every plastic film tested has produced sarcomas in a certain percentage of instances. 5. Other foreign bodies, such as linters, surgical cotton and glass cover-slips similarly imbedded in the anterior wall of rats have not produced malignant tumors. 6. No adequate explanation of the mechanism of this carcinogenic effect of imbedded plastic films has been found. 7. The experiments have been limited to rats and mice.