Damage and repair of DNA in various tissues of the rat induced 4-nitroquinoline 1-oxide.

4-Nitroquinoline 1-oxide induces pulmonary tumors when given by a s.c. route or skin cancer by repeated local applications. This carcinogen is absorbed by the lung more readily than other tissues. Therefore, we have compared the ability of 4-nitroquinoline 1-oxide to damage DNA of the liver, lung, and kidney in the intact animal. A differential effect of DNA damage was detected in all three organs, with the lung showing the greatest amount of damage. All three tissues were able to repair the damaged DNA. The preferential damage of rat lung DNA by 4-nitroquinoline 1-oxide correlates with the specificity of this carcinogen to induce pulmonary tumors.