Genotoxicity related to aminoarenes and nitroarenes was evaluated with matters produced during incineration, which would be induced by charred proteins and/or petroleum. We investigated the genotoxicity on discharge water from sludge incineration stokers in a sewage treatment plant using the activated sludge treatment method, fly ash and bottom ash of incineration plants of domestic waste and leachate by using the umu-test which can detect with high sensitivity genotoxicity with aminoarenes and nitroarenes.
Strong genotoxicity could be detected in the fly ash related to aminoarenes and the step grate stoker furnace incinerating sludge and leachate. These facts show that the incineration processes can induce those materials, amino and/or nitroarenes with genotoxicity.

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A large quantity of PCDDs/DFs is discharged from municipal solid waste incinerators in Japan. In this study, a material flow of PCDDs/DFs was analyzed in a municipal solid waste incineration system. As a result, the total amount of PCDDs/DFs released, which contained PCDDs/DFs not only from emission gas but also from residues, was 160 μg TEQ/waste-ton and exceeded the amount of PCDDs/DFs input into the system (1.4-50 μg TEQ/waste-ton), and more than 90 percent of PCDDs/ DFs released was contained in fly ash. As a consequence of the scenario analysis, in the case of controlling incinerators with high technologies, the total amount of PCDDs/DFs released was ex-pected to be 3.65-34μg TEQ/waste-ton, which was nearly equal to or below the amount of PCDDs/ DFs input. In the case of melting or heating dechlorination of fly ash in addition, the total amount of PCDDs/DFs released was expected to be reduced to 0.85-4.6 μg TEQ/waste-ton.

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If molten slag can be used as concrete aggregate, a large amount of slag can be utilized. So, most of the slag made of MSW incineration residue will be able to be used as a sand alternative. This means that it's possible to preserve some natural resources, because sand consumption is partly replaced by the slag. In spite of this merit, when water, slag and cement are mixed, hydrogen gases sometimes evolve, which causes gas bubbles in the concrete. In this study to prevent such gases from evolving, we made slag of different MSW incineration residues and by changing the furnace conditions, resident time and melting temperature. Mixing the slag, cement and water, the evolved gas volume was measured. We were able to find several relationships between the evolved gas volume and these conditions.

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Agricultural PVC film containing PVC 64.5%, DOP (dioctylphthalate) 32% as a plasticizer, Ca-Zn stearates and surface active agent was treated in 0-7 M NaOH solutions at 150-250°C for 0-12h, in order to study the behavior of degradation and characteristics of produced char.
The degree of weight loss due to the decomposition reached 31% for the reaction in 3 M NaOH over 225°C for Oh, which corresponded to the loss of all the plasticizer contained in the agricultural PVC film. Under the same conditions, DOP was hydrolyzed quantitatively to phthalic acid and isooctyl alcohol by the alkali catalyst. In the hydrothermal reaction, the pores in size 10-12, em were produced in the film by the hydrolysis of DOP, besides the succeeding parallel dehydrochlorination of PVC produced smaller pores and brought about the shrinkage of film. The pore size became smaller, about 1-8μm for 12h, along with time.

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The authers reported about mutagenic activities and mutagenic compounds in exhaust gas from municipal waste incinerators in steady operation term.
In this study, mutagenic activities and concentrations of PAHs at starting and stopping terms of the municipal waste incinerators were investigated in comparison with these in the steady operation term.
Mutagenic activities of the exhaust gas were higher in fluidized bed furnaces where CO concentration were widely varied. However, they were not higher at starting and stopping term than steady operation term. The mutagenic activities at starting term were higher than steady operation term when large amount of solid wastes was fed in furnace for quick heating. On the other hand, the mutagenic activities at stopping term were not higher than steady operation term in all the incinerators.
In order to decrease the mutagenic activities, the incineration must be started by gradual feeding wastes or preheating with oil, be fed wastes constantly in steady term, and be supplied full volume air in stopping term as in steady operation term.
Mutagenic activities increased with the concentration of fluoranthene and benzo (b) fluoranthene, but these mutagenic levels were almost same and their contribution ratios for the mutagenic activities of the exhaust gas were low in every term.

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About 65% of coal ash is used as raw material for cement, cement mixture material and so on. However, there is a limit in the improvement of availability without processing in coal ash because there are changes in the quality, coal ash is a fine powder, and the leaching of toxic heavy metals exceeds a standard values for utilization. There, the lime-pozzolana reaction characteristic of coal ash was used, coal ash was kneaded with water, and the mixture was processed under saturation steam atmosphere at about 60°C, eventually turning into a hardend solid. The hardend solid was crushed and was adjusted in grains of 40 mm or less in size. To materialize a large amount of utilization technique as civil materials such as a road base material and so on by granular hardend solid, it was carried out research concerning safety to the environment and stability in quality. It was confirmed that the leaching quantity of toxic heavy metals satisfied the standard value for utilization, and strength of the granular hardend solid improved with the passage of time, for a long term under road base environmental conditions. Furthermore, it was confirmed by actual long term road tests that the granular hardend solid maintained the quality more than the equal to crushed stone to be a representative road base material.

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