Futoshi Ikeda* and Hidehiro Kaneko**

* Graduated Students, Faculty of Engineering, Yamanashi University (EBARA CORPORATION)
** Faculty of Engineering, Yamanashi University

+ Correspondence should be addressed to Hidehiro Kaneko:
(4-3-11 Takeda, Kofu, Yamanashi 400 Japan)

Abstract

The effect of extraction conditions (S/L and pH) on the toxicity evaluation of a municipal waste incinerator's (MWI) fly ash was examined by quantitative analysis and the Daphnia acute toxicity test. Regarding S/L, the toxicity of MWI fly ash per unit amount of fly ash, which was determined with the leachate prepared with S/L = 1w/v%, was larger than that which was determined with the leachate prepared with 10w/v%. Regarding pH, the leachate prepared with pH = 4 showed higher toxicity than that prepared with pH = 7 or 12. The leaching condition with pH = 12, however, was considered preferable in order to evaluate the release of lead, because the release of lead under this pH condition was higher than that of other pH conditions. Considering the relationship of pH dependency to the toxicity of leachate, the major toxic constituent in the leachate prepared with pH = 4 was copper, and that prepared with pH = 12 was lead.

Key words: fly ash, toxicity, extraction condition, Daphnia acute toxicity test