Rice Germination as a Bioassay to Test the Phytotoxicity of MSWI Bottom Ash Recycling Wastewater

Abstract

This experiment assessed the phytotoxicity effect of untreated wastewater and treated wastewater from a municipal solid waste incineration (MSWI) bottom ash recycling facility on the germination rate and root elongation of two rice varieties (Var139 and Var9) in Taiwan. The results show that undiluted (treated and untreated) MSWI bottom ash recycling wastewater had more adverse effect on rice seed development than the 50% diluted wastewater. Between the two varieties, Var139 showed a higher performance than rice Var9 in diluted wastewaters. A short exposure (5 days) of 50% MSWI bottom ash wastewater presented no environmental risk for root development of both crops. However, short exposure of this wastewater at higher concentration (100%) significantly affected seed germination and root elongation.