A Review of Stable Isotope Labeling and Mass Spectrometry Methods to Distinguish Exogenous from Endogenous DNA Adducts and Improve Dose-Response Assessments for Chemicals with both Exogenous and Endogenous Exposures.

Authors: Kun Lu, Yun-Chung Hsiao, Chih-Wei Liu, Rita Schoeny, Robinan Gentry, and Thomas B. Starr

Some chemical carcinogens can produce DNA adducts and DNA adducts have been used as biomarkers of exposure. However, DNA adducts of various types are also produced endogenously in the course of normal metabolism. This review summarized a highly applicable methodology, termed Stable Isotope Labeling and Mass Spectrometry (SILMS), which is superior to previous methods as it not only provides absolute quantitation of DNA adducts, but also differentiates the exogenous and endogenous origins of DNA adducts.