Induction of micronuclei and nuclear abnormalities in common toad tadpoles (Rhinella arenarum) treated with Liberty® and glufosinate ammonium.

LAJMANOVICH, R.C.; CABAGNA ZENKLUSEN, M.C.; ATTADEMO, A.M.; JUNGES, C.M.; PELTZER, P.M.; BASSÓ, A.; LORENZATTI, E.A.

MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 769 p. 7 - 12

1383-5718

The detection of micronucleated erythrocytes (ME) in blood represents a widely 29 used method for the detection of chromosome damage by chemical water contaminants 30 such as herbicides. We investigated the changes in some circulating blood cell 31 parameters of common toad (Rhinella arenarum) tadpoles that were exposed to three 32 sublethal doses (3.75, 7.5, and 15 mg/L) of a commercial formulation of a glufosinate33 ammonium (GLA)-based herbicide (Liberty®, LY®) as well as to the corresponding 34 active ingredient GLA for 48 and 96 h. The frequency of ME and other erythrocyte 35 nuclear abnormalities (ENAs, i.e., lobed nuclei, binucleates or segmented nuclei, kidney 36 shaped nuclei, notched nuclei, and picnotic nuclei) were evaluated and compared with 37 positive (cyclophosphamide, CP, 40 mg/L) and negative (dechlorinated tap water) 38 controls. The results reported in the present study indicate that the exposure of R. 39 arenarum tadpoles to LY® and GLA induces a concentration-dependent increase in ME 40 frequency. The ENAs frequency also increased significantly at 48 h in all the chemicals 41 assayed (CP, LY® and GLA) respect to the negative control, whereas at 96 h, 42 differences in ENAs were found between CP and GLA (7.5 mg/L) respect to the 43 negative control. Our study demonstrates that the commercial formulation of a GLA44 based herbicide induces micronuclei formation in R. arenarum tadpoles, in contrast with 45 the active ingredient. According to these results, the inert ingredients of the commercial 46 formulation played an important role in the production of this genotoxic damage in 47 erythrocytes of amphibian tadpoles.