Table of Contents
ISRN Toxicology
Volume 2011, Article ID 954626, 6 pages
http://dx.doi.org/10.5402/2011/954626
Review Article

Analysis of Ammonia Toxicity in Landfill Leachates

1Department of Chemical Science and Engineering, Tokyo National College of Technology, 1220-2 Kunugida-Machi, Hachioji, Tokyo 193-0997, Japan
2Research Center for Material Cycles and Waste Management, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-8506, Japan

Received 23 May 2011; Accepted 6 July 2011

Academic Editor: A. H. Milton

Copyright © 2011 Takuya Osada et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Toxicity identification evaluation (TIE) phase I manipulations and toxicity test with D. magna were conducted on leachates from an industrial waste landfill site in Japan. Physicochemical analysis detected heavy metals at concentrations insufficient to account for the observed acute toxicity. The graduated pH and aeration manipulations identified the prominent toxicity of ammonia. Based on joint toxicity with additive effects of unionized ammonia and ammonium ions, the unionized ammonia toxicity ( L C 5 0 , N H 3 ( a q ) ) was calculated as 3.3 ppm, and the toxicity of ammonium ions ( L C 5 0 , N H 4 + ) was calculated as 222 ppm. Then, the contribution of ammonia toxicity in the landfill leachate toxicity was calculated as 58.7 vol% of the total toxicity in the landfill leachate. Other specific toxicants masked by ammonia's toxicity were detected. Contribution rate of the toxicants other than by ammonia was 41.3 vol% of the total toxicity of the landfill leachate.