2006 Volume 9 Issue 1 Pages 11-21
Toxicity identification evaluation (TIE) methods were used to characterize the compounds causing leachate toxicity. The toxicity screening tests were conducted on leachates from industrial and municipal solid waste landfill using freshwater (Daphnia magna) and marine organisms (Brachionus plicatilis, Artemia franciscana and Vibrio fischeri). Only D. magna and V. fischeri exhibited higher sensitivity to studied samples and used as test species in TIE analysis. The results from combining TIE analysis and physical-chemical analysis suggested that less polar organic compounds might be responsible for leachate toxicities. In addition to organic contaminants, the toxicity stemming from the total dissolved solids (TDS) and volatile substances that partly contributed to the toxicity in municipal landfill leachate were detected using D. magna. In this study, D. magna had a higher potential than V. fischeri to differentiate the toxicity of leachate samples with different chemical characteristics. The Microtox test displayed a higher sensitivity to organic compounds. The Cu concentration in municipal landfill leachate samples was sufficiently high to be toxic to D. magna, but the results of TIE-analysis indicated that Cu might not contribute to leachate toxicity. This fact suggested that the method combining the chemical analyses and TIE manipulations with the toxicity tests was essential to gain more insight into the possible causes of toxicity.
