DECOMPOSITION OF DIOXINS IN SOIL OF PADDY FIELDS AND SOIL OF MUNICIPAL SOLID WASTE INCINERATOR SURROUNDINGS USING SUNLIGHT AND HYDROGEN PEROXIDE

摘要

A large amount of dioxins are stocked in Japanese environment such as paddy soils and surrounding ones of solid waste incinerators. To reduce these stocks of dioxins is necessary to reduce the risk of them to human and ecosystem exposure. In this study, dioxins in paddy soil and incinerator surrounding soil were tried to decompose. One gram of the sample soil was suspended in 300 ml of hydrogen peroxide (H2O2) solution. August's sunlight was irradiated in the former case for 9 hours, and xenon light was irradiated in the latter case for the same hours. As a result, the TEQ in the former soil decreased by 98% at H2O2 12%. In the latter case, it had exceeded the Japanese environmental criteria for soil (1,000pg/g), but decreased by 81% at 12% H2O2 to well below 250pg/g in which a governmental organization was requested to start to investigation.