Evaluating the mutagenicity of leachates obtained from the bottom ash of a municipal solid waste incinerator by using a Salmonella reverse mutation assay

Chemosphere. 2015 Apr:124:70-6. doi: 10.1016/j.chemosphere.2014.11.013. Epub 2014 Nov 27.

Abstract

The mutagenic potential of leachates derived from the bottom ash of a municipal solid waste incinerator in Taiwan were evaluated using an Ames Salmonella mutagenicity assay with three standard tester strains, TA98, TA100, and TA1535. Three types of leachants, leachant A (pH 4.93), leachant B (pH 2.88), and leachant C (deionized water, pH 6.0), were carried out according to toxicity characteristic leaching procedure (TCLP). Moreover, two types of bottom ash, nonsieved and sieved bottom ash (particle size <4.75 mm), were analyzed with the TCLP and the Ames assay. The concentrations of five heavy metals (Cd, Cr, Cu, Pb, and Zn) in the leachates were also estimated with an ICP-OES. The results indicated that the metal concentrations in the TCLP leachates of bottom ash were all below the limits set by Taiwanese regulations. However, leachate A from nonsieved and <4.75-mm-sieved bottom ash showed mutagenicity. Moreover, leachate A from <4.75 mm-sieved bottom ash displayed stronger mutagenicity than that from nonsieved ash. The leachate A from <4.75-mm-sieved bottom ash, that were diluted by 100-fold showed no mutagenicity. In conclusion, our results suggested that the chemical composition and mutagenic potential of leachates should be monitored to evaluate the safety of bottom ash.

Keywords: Ames test; Biotoxicity; Bottom ash; Mutagenicity; TCLP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Coal Ash / toxicity*
  • Environmental Pollutants / toxicity*
  • Incineration
  • Metals, Heavy / toxicity*
  • Mutagenicity Tests
  • Mutagens / toxicity*
  • Salmonella / drug effects*
  • Solid Waste / analysis
  • Spectrophotometry, Atomic

Substances

  • Coal Ash
  • Environmental Pollutants
  • Metals, Heavy
  • Mutagens
  • Solid Waste