Cotinine and N-(2-hydroxyethyl)valine as markers of passive exposure to tobacco smoke in children

J Expo Anal Environ Epidemiol. 2005 Jan;15(1):66-73. doi: 10.1038/sj.jea.7500344.


Large segments of populations, including children, are exposed to environmental tobacco smoke (ETS), a risk factor for lung cancer and heart, circulatory and respiratory diseases. Recently, ETS was classified as a class A carcinogen by USEPA, as carcinogenic to humans by IARC (group 1) and by the National Toxicology Program of the US National Institutes of Health. Cotinine, a product of the metabolism of nicotine, is measurable in urine and, correlates strictly and directly to ETS exposure, therefore representing a well-known internal dose marker. Another marker of active tobacco smoking is the N-(2-hydroxyethyl) valine (HOEtVal) which results from the reaction between ethylene oxide (EtO) and the N-terminal valine of hemoglobin. The aim of this study was the evaluations of ETS markers, namely urinary cotinine and HOEtVal measured in blood in 100 children with ages ranging between 3 and 13 years. Experimental findings show that cotinine, as a specific internal dose marker, and HOEtVal, as a nonspecific biological effective dose marker, both depend on the passive exposure to ETS as well as on the active habit of smoking.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Biomarkers / urine*
  • Child
  • Child, Preschool
  • Cotinine / urine*
  • Environmental Exposure*
  • Female
  • Humans
  • Male
  • Reference Values
  • Sensitivity and Specificity
  • Tobacco Smoke Pollution*
  • Valine / analogs & derivatives*
  • Valine / urine*


  • Biomarkers
  • Tobacco Smoke Pollution
  • 2-hydroxyethylvaline
  • Valine
  • Cotinine