Development of Simplified Method for Algal Growth Inhibition Test and Its Application to the Assessment of Total Hazard in Landfill Leachate Samples

Abstract

To evaluate the total hazard existing in effluent water, three different bioassays, namely, the in vitro basal cytotoxicity test using a human cell line, bioluminescence inhibition test using luminescent bacteria and algal growth inhibition test, were applied to landfill leachate samples. To simplify the algal growth inhibition test, a new method using 96-well microplates and a microplate fluorometer was developed. Based on the results obtained using the bioassays, scoring of the total hazard existing in the samples was attempted. While the scores obtained with the basal cytotoxicity and bioluminescence inhibition tests showed similar patterns, those obtained with the algal growth inhibition test showed a different pattern. Nevertheless, the total scores of the samples indicate that the total hazard existing in raw leachate was significantly reduced by a wastewater treatment process. Thus, this type of scoring of the total hazard existing in landfill leachate may be useful for priority setting for the risk management of landfill sites.