The methods applied for DNA adduct determination in humans have become more reliable. Yet there is a need to characterize the adducts studied better and when possible, to identify them with the help of the available standard compounds. Use of standard compounds also allows quantification of adduct levels. There is a lack of knowledge on the adduct levels and their half-lives in target and surrogate tissues. Most adduct studies have been carried out on occupational populations exposed to complex mixtures. White blood cells have been the most common source of DNA. Other exposures and tissues should be a subject of study. Notably, dietary exposures have been largely neglected. Biomonitoring of mutations is a relatively new field and a few exposures have so far been investigated. The results have been promising but logistics of the studies have to be improved to make large field studies possible. Future biomonitoring studies should make an effort to combine many end points, with emphasis on adducts, mutations, and constitutional metabolic factors.