title: Relationships between formation of micronuclei and DNA adducts and EROD activity in newts following exposure to benzo(a)pyrene.
abstract: The aim of this study was to determine whether the micronucleus test, using the larvae of a lower invertebrate, the newt Pleurodeles waltl, is suitable for evaluating the overall genotoxicity of polluted water (AFNOR Standard, 1992). The study used the pollutant model benzo(a)pyrene (BaP). After having shown that BaP is metabolized by the larvae, the test was carried out under standard AFNOR conditions. We investigated the relationship between the BaP concentration, spectrofluorometric measurement of liver EROD activity, and two genotoxicity biomarkers: DNA adduct production (32P-postlabeling detection) and micronucleus formation in red blood cells (RBCs) (number of micronucleated RBCs per 1,000). A dose effect was found for all three biomarkers, which were seen to be linearly correlated showing that the biochemical mechanisms occurring in the newt larvae exposed to BaP are similar to those described in higher vertebrates. This result confirms the utility of the test for the evaluation of the overall hazard of a given aquatic environment.
authors.affiliation: Centre de Biologie du Développement, Université Paul Sabatier, Toulouse, France.
authors.forename: J
authors.initials: J
authors.lastname: Marty
authors.forename: J E
authors.initials: JE
authors.lastname: Djomo
authors.forename: C
authors.initials: C
authors.lastname: Bekaert
authors.forename: A
authors.initials: A
authors.lastname: Pfohl-Leszkowicz
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000493:pharmacokinetics / Q000633:toxicity*; D015415:Biomarkers; D001711:Biotransformation; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism*; D018736:DNA Adducts; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D007814:Larva; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D015162:Micronucleus Tests; D009153:Mutagens / Q000493:pharmacokinetics / Q000633:toxicity*; D012455:Salamandridae
chemical_list: D015415:Biomarkers; D018736:DNA Adducts; D009153:Mutagens; C056612:benzo(a)pyrene-DNA adduct; D001564:Benzo(a)pyrene; D019363:Cytochrome P-450 CYP1A1