Assessment of the effect of a commercial formulation of Methomyl on reproduction of Daphnia obtusa Kürz (1874)
-
-
[1] Universidad de Valparaíso
-
- Localización: Latin American Journal of Aquatic Research, ISSN-e 0718-560X, ISSN 0716-1069, Vol. 41, Nº. 5, 2013, págs. 979-984
- Idioma: inglés
- Enlaces
-
Resumen
The aim of this study was to evaluate the effect of a commercial formulation of Methomyl on the reproduction in Daphnia obtusa. Neonates (<24 h) were exposed to concentrations of insecticide (1.0, 1.5, 2.0, 2.5, 3.0 µg L-1) for a period of 21 days. The results showed a significant decrease in the number of molts, total neonates, fertility and sex ratio index. Significant regressions were found between reproductive parameters and concentrations of the insecticide: molts (R2= 0.96), fertility (R2= 0.97), number of female neonates born per female (R2= 0.90), and the number of male neonates born per female (R2= 0.94). Embryotoxicity was also observed; the number of neonates born with malformations increased in the highest concentrations of Methomyl 90 SP® tested. In conclusion, Methomyl 90 SP® inhibits reproduction of D. obtusa. However, a clear effect as an endocrine disrupter was not observed. This insecticide is embryotoxic; it causes malformations in neonates of Daphnia obtusa.
