Genetic and biochemical biomarkers in the macrophyte Bidens laevis L. exposed to a commercial formulation of endosulfan

PÉREZ, DÉBORA JESABEL; LUKASZEWICZ, GERMÁN; MENONE, MIRTA LUJÁN; AMÉ, MARÍA VALERIA; CAMADRO, ELSA LUCILA

ENVIRONMENTAL TOXICOLOGY

JOHN WILEY & SONS INC

Lugar: New York; Año: 2014 vol. 29 p. 1063 - 1071

1520-4081

ABSTRACTPrevious studies in the wetland macrophyte Bidens laevis L have demonstrated that the insecticide endosulfan induces a high frequency of somatic chromosome aberrations in anaphase?telophase (CAAT), but no DNA changes as determined by the single cell gel electrophoresis (Comet) assay. Thus, cytogenetic biomarkers appear to be more sensitive to the toxic effects of the insecticide than the DNA molecule in the studied species. For this reason, the goals of this study were to use cytogenetic biomarkers - CAAT and abnormal metaphase- and defense biomarkers such as the activity of the antioxidant enzymes ?guaiacol- peroxidases (POD), glutathione reductase (GR) and microsomal and cytosolic (m- and c-) glutathione-S-transferase (GST)- to evaluate in B. laevis effects caused by a commercial formulation of endosulfan. The frequency of CAAT were increased at 5, 10, 50 and 100 ug/L endosulfan with respect to the negative controls, by 3.1, 2.5, 2.5, 3.2-fold, respectively while the frequency of abnormal metaphases was also increased at the same concentrations by 3.5, 2.8, 3.2, 11.3-fold respectively. In addition to these aneugenic effects, other abnormalities such as C-Mitosis and  chromosome clumping were observed at 10 ug/L endosulfan. On the other hand, POD induction at 0.02, 0.5, 5 and 10 ug/L and m- GST inhibition at 0.5, 10 and 50 ug/L in plants exposed during 24 h to endosulfan were observed but all of these responses were highly variable. In conclusion, only cytogenetic biomarkers like CAAT in B. laevis can serve potentially as early warning systems to detect environmentally relevant concentrations of endosulfan in aquatic ecosystems. Key Words: genotoxicity, chromosome aberrations, commercial formulation of endosulfan, wetland macrophytes, peroxidases.