Objective The project is aimed at developing methods to detect DNA adduct in microsamples of genomic DNA for direct evidence of exposure to environmental genotoxins. The measurement of carcinogen deoxyribonucleic acid (DNA) adducts provides both a direct indication of exposure and an early indication of the potential genetic effects which may be produced by a carcinogen.1.3-Butadiene (BUT), a chemical used in the production of synthetic rubber is a potent multisite carcinogen in mice. In humans, epidemiological data showed an increase in lymphomas, leukaemias and other cancers of the haematopoietic system associated with BUT exposure. BUT is metabolized to 1.2-epoxy-3-butene (EB) and 1.2:3.4-diepoxybutane (DEB).Main interest has been focused on investigating DNA alkylation following exposure to DEB, especially in relation to the development of a method for human biomonitoring. Following the reaction of deoxyadenosine monophosphate (dAMP) and polydeoxyadenosine-deoxythymidine (poly dA-dT) with DEB and subsequent high performance liquid chromatography (HPLC), a major adenine adduct has been identified and a HPLC phosphorus-32 postlabelling (32PPL) method for its detection in DNA samples has been developed. This method and the use of synthetic DEB-dAMP as a reference compound for the optimization of the procedure, permitted the detection of the modified adenine in calf thymus DNA and DNA from treated Chinese hamster ovary (CHO) cells.In DNA from CHO cells only one spot, corresponding to the first component of the adduct, was detected on the thin layerchromatography (TLC) plate after HPLC and 32PPL. This may be due to a different accessibility of DNA when packaged as chromatin, leading to the formation of only 1 isomer of the DEB-adenine derivative or to a differential repair of the isomers.Studies on the identification of biomarkers in fish were carried out on in vivo cat fish and on in vitro primary culture of hepatic cells. In in vivo studies, the bile from catfish exposed to 3H-Benzopyrene was collected several days after treatment as analysed by HPLC.The formation of DNA Adducts after exposure to genotoxic chemicals is a primary event in cancer initiation. The measurement of carcinogen DNA adducts can provide both a direct indication of exposure and an early indication of the potential genetic effects which may be produced by a carcinogen. Main interest has been focused on investigating DNA alkylation following exposure to DEB, especially in relation to the development of a method for human biomonitoring. Programme(s) JRC-EXPLORES 2C - Specific research programmes (EEC) to be implemented by the Joint Research Centre - Exploratory research -, 1992-1994 Topic(s) Data not available Call for proposal Data not available Funding Scheme Data not available Coordinator Joint Research Centre (JRC) EU contribution No data Address Edificio 29 21020 Ispra Italy See on map Total cost No data
