Determination of toxicity and ecotoxicity of chemicals, pesticides and biocides using zebrafish embryos.

BICHARA, D.; ARRANZ, S.E.; CALCATERRA, N.B.; ARMAS, P.

Rosario, Santa Fe, Argentina.

Workshop; 1st Argentinean Workshop in Environmental Science.; 2009

Fac. Cs. Bioq. y Farm. - U.N.R.

The introduction of chemicals into the environment by human activities represents a serious risk to environmental and human health. Therefore, information about the toxicity of chemicals, pesticides, biocides and pharmaceutical drugs is required. Common eco-toxicity tests make use of adult fish specimens to evaluate aquatic toxicity. However, there is an increasing ethical demand for the replacement of animal tests. One convenient choice is the use of the “fish embryo toxicity assay”, which has been demonstrated to correlate with acute fish assays. This test is performed with non-hatched embryos of the zebrafish Danio rerio, allowing to determine the toxicity of a substance or liquid sample by using 24-well multiplates. We have optimized our zebrafish facility for the test conditions and evaluated several reference drugs in order to contrast our results with results from other laboratories. Moreover we designed a variant test using a single 96-well multiplate to perform the complete assay, that allow to rapidly obtain the LC50 for a drug or liquid sample in short times and using low volumes. The test was performed using commercial formulations of the broad-spectrum systemic herbicide glyphosate (N-phosphonomethyl glycine) and the insecticide cypermethrin (cis and trans mixture of cyano-3-phenoxybenzyl-2,2-dimethylcyclopropanecarboxylate). Results from these assays indicate LC50 values that are 1000-fold (in the case of glyphosate) and 2-fold (in the case of cypermethrin) lower than the concentrations used in Soya farming lands. In addition, taking advantage of the zebrafish as an excellent model organism for the study of physiological function, here we present the design and construction of the molecular tools for the generation of a transgenic fish line that will result useful to detect liver cellular damage in vivo by using bimolecular fluorescence complementation strategy.