LOS EFECTOS TERATOGENICOS COMO EXPRESION DE CALIDAD AMBIENTAL ACTUAL Y DESDE UNA PERSPECTIVA EVOLUTIVA

J. HERKOVITS; C.S. PÉREZ-COLL; L.A. CASTAÑAGA; M.T. SANDOVAL; C. ASOREY; L. MUÑOZ; C. ZUCKERBERG; C.M. ARONZON

Salud ambiental y humana. Una vision holistica

SETAC

Lugar: Buenos Aires; Año: 2006; p. 88 - 90

Teratogenesis is accepted as a highly significant end point for hazard assessment of physico-chemical agents while from the evoecotoxicological perspective, ontogenic features such as the stage-dependent susceptibility to noxious agents could be considered biomarkers of ancient environmental conditions. In this contribution the notorious stage-dependent susceptibility to environmental pollutants is reported focusing on teratogénesis produced by UVB radiation on Bufo arenarum embryos. The ED50 of UVB (J/m2 at 168hr post exposure) ranged from 800 at gill circulation stage up to 12.312 at blastula. The main adverse effects were delayed development, reduced growth, asymmetry, acephaly and tail flexures. Taking into account that the ozone shelter developed after free oxygen was available, that is from 2.4 billion years ago onwards, the very high resistance to UVB radiation at blastula supports the hypothesis that multicellular ancestors of amphibians flourished in the anoxic Earth.