Masataka Hanashima* and Ayako Tachifuji*

* Department of Civil Eng., Faculty of Eng., Fukuoka University

+ Correspondence should be addressed to Ayako Tachifuji:
(8-19-1, Nanakuma, Jonan-ku, Fukuoka 814-0180 Japan)

Abstract

Recently, the influence of chemicals such as carcinogens and endocrine disrupters on the ecosystem has become a serious problem in Japan. Attention has, therefore, gathered around a bioassay including a genotoxicity (mutagenicity) test. We focused on a mutagenicity related with carcinogenicity as a safety assessment index of landfill and have been investigating the mutagens in waste and leachate since 1986. This paper provides a summary of the results of our investigation. The main results are shown below.

1) The mutagens in leachate are effectively adsorbed on Sep-Pak CSP800 in lower pH (pH2) . 2) Most mutagens in leachate are a direct mutagen induced frameshift mutation which is detected by using S. typhimurium TA98 without S9, so that we can simplify the mutagenicity test. 3) The fate of mutagens in landfill depends on aerobic biodegradation; the more the landfill layer is aerobic, the faster the degradation of mutagens. 4) The problems to be solved are to establish a detection method for hazardous nongenotoxic chemicals, to decide whether premutagens should be included in the mutagens from the viewpoint of risk assessment or not, and to identify the mutagens.

Key words: landfill, mutagenicity, safety assessment index, premutagen, fate of mutagen in landfill