Binding of tritium-labeled polycyclic hydrocarbons to DNA of mouse skin.

Evidence was obtained to confirm previous observations of the firm binding of certain carcinogenic polycyclic hydrocarbons to the DNA, RNA, and protein isolated from mouse skin after the in vivo application of these compounds. The possibility of the influence of several artifactual causes of hydrocarbon binding to DNA was carefully investigated, and it was concluded that the binding that is measured represents the true extent of metabolic reaction between the hydrocarbon and the DNA of mouse skin. The correlation between the extent of binding to DNA and carcinogenicity was studied, and two instances were observed in which binding of a hydrocarbon to DNA was not associated with a carcinogenic event. The possible relationships between these findings and carcinogenicity are discussed.