Abstract
Ecological effects of p-octylphenol a kind of environmental estrogen to Culex pipien molestus were assessed in order to develop the use of Culex pipiens molestus as model organism. The immature stages (from egg to pupa) of Culex pipiens molestus were exposed to p-octylphenol and monitored for alterations in molting, development time, mortality and fecundity. The emergence of female adults was delayed by exposure. p-octylphenol also reduced reproduction capacity (numbers of eggs produced per larvae), which showed the ups and downs depending on the size of population, at concentrations ranging from 10 to 100 μg/L. The weight of adult female decreased at same concentrations. These results indicate that p-octylphenol interfered in the growth of Culex pipiens molestus, and thereby decreased the weight of adult female. Further, this inhibition led to decrease reproduction capacity which included development and fecundity parameter. But these effects were not observed at 125 μg/L. Reproduction capacity may be used for endocrine-sensitive endpoint in the Culex pipiens molestus reproduction test. These endpoints and some knowledge of endocrine systems suggest that Culex pipiens molestus may have potential as model organism of endocrine disrupters.
