Abstract
Because the waste treatment is regarded as one of the major sources of environmental contaminations by hazardous substances, regulations against hazardous wastes were newly established and revised. The Waste Disposal and Public Cleansing Law and the criteria of the hazardous waste were revised, and then more volume of hazardous wastes were treated specially. Internationally, ocean dumpings of wastes will be prohibitted and transboundary movements of hazardous wastes were regulated. In Japan, environmental contaminations caused by the waste disposal have not been revealed. However, leachates from landfill sites were found to include various hazardous substances and they were proved to be toxic by bioassay tests.
