We verified and modified the measuring method of the EROD activity of in vivo using zebra fish larvae developed by Noury et al., and examined the possibility of connecting this method to Short-term Toxicity Test on Embryo and Sac-Fry Stages such as “WET test” or “draft protocols of effluent testing using bioassays” based on OECD TG No.212. As a result, we found that our method of measuring in vivo EROD activity is possible to connect to “WET test” or “draft protocols of effluent testing using bioassays”, as long as the same lot of embryo and larvae of the same hatch date are used. In addition, comparing with different test using the other lot of embryo or calculating equal concentration of model EROD inducer could be possible, by installing positive control for every test and calculate the specific EROD activation（%）. Moreover, we applied this method to environmental water and validity was proved.
Therefore, this method could be one option in acquiring information about the chemical substance contained in the effluent or environmental water, by connecting it with the “WET test” or “draft protocols of effluent testing using bioassays”.

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Biotic ligand model（BLM）was modified to predict metal mixture effect on algae based on the assumption that toxic mode of action is same among metals. Algal toxicity test of Zn, Cu, and Cd using green alga Pseudokirchneriella subcapitata was conducted, and the result was used for deriving BLM parameters. In addition, metal mixture algal toxicity test was conducted under the combination of Zn-Cu, Zn-Cd, and Cu-Cd. The experimental data was compared to prediction by mixture BLM. Furthermore, existing predictive models of mixture effect, concentration additive model and independent action model, were also used for predict metal mixture effect. Independent action model was the best predictor, suggesting that the toxic mode of action green algae differ among these metals.

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