Abstract
Biological effects of raw and treated wastewater were evaluated by selecting gene expressions for sexual reproduction and growth in male and female Medaka, and after 96 hour exposure to the samples by comparing the differences in the extent of the gene expressions between control and exposure in the form of Euclidian distance. In addition, reproduction tests using adult Medaka were carried out in the treated wastewater in order to clarify the relationship between the gene expression level and egg laying. As a result, by the treatment of activated sludge process and microbial carrier, biological effects evaluated by the gene expression were reduced to the level of a river with the category of Aquatic life A of the environmental quality standards for conservation of aquatic lives. Also, adverse effect of treated wastewater on the egg laying was not confirmed.
