Biomarkers 7 : Are broadly defined as indicators signaling events in biologic systems or samples. They have been classified as markers of exposure, markers of effect, and markers of susceptibility
Department of Health and Human Services (US federal public health agency), The Agency for Toxic Substances and Disease Registry (ATSDR), Glossary (Total Petroleum Hydrocarons), GA, USA 1999. http://www.atsdr.cdc.gov/toxprofiles/tp123-c9.pdf, (Globally Harmonized Sys of Class and Labl of Chem - Brit) {635}