Akio Kamiya

Mutagenic activity and PAH analysis in municipal incinerators

Abstract We have investigated the mutagenic activity of fly ash and emission gases from municipal waste incinerators. A negative relationship was obtained for complete combustion and a positive one for incomplete combustion. There were more mutagens in emission gas than in precipitated fly ash and residual ash. The total revertants per minute for emission gas discharged from the incinerator to the environment corresponded to those for 1700–3000 motor vehicle exhausts. Various polycyclic aromatic hydrocarbons (PAHs) were detected as a result of incomplete combustion and most of the mutagenic substances were released into the environment from the municipal incinerator as volatile emission gases. Urban waste incinerators are the main source of environmental pollution which results from incomplete combustion.

Study of odorous compounds produced by putrefaction of foods : V. Fatty acids, sulphur compounds and amines

Abstract An investigation was made of the relationship between odour and odorous compounds in solid waste. A variety of foods were kept separately in 20-1 polyethylene bottles at 23°C for 3 months and chemical analyses of the headspace gas and leachate were performed at regular intervals. In addition, the offensive odours were characterized by sensory tests. It was found that fatty acids and sulphur compounds were the main components producing the offensive odour of domestic waste and amines do not play an important role.

Study of the behaviour of mutagens in wastewater and emission gas from a municipal incinerator evaluated by means of the ames assay

We have investigated the mutagenic activity of extracts from the wastewater of sewage treatment plants in municipal waste incinerators and evaluated the relative contribution of various routes of emission from the incinerator to the total output of mutagens. The mutagenicity of wastewater extracts from a complete combustion incinerator was 10% of that from an incomplete combustion unit. About 90% of all the mutagens produced in a municipal incinerator are discharged into the atmosphere as emission gases, and 10% are disposed of in the wastewater treatment plants. Most of the mutagens in wastewater treatment plants are not decomposed by normal aeration times, but are removed by adsorption onto suspended solids.

Isolation of dinitropyrene in emission gas from a municipal incinerator and its formation by a photochemical reaction

In a previous paper, direct-acting mutagenicity was reported in emission gas from incomplete municipal incineration using Salmonella typhimurium TA-98 and TA-100. This paper reports the detection of dinitropyrene (DNP) as a direct-acting mutagen using nitrogen selective gas chromatography. The gas-phase photochemical reaction of pyrene with nitrogen dioxide was examined in a quartz vessel with various reaction times and temperatures. 1-Nitropyrene (1-NP) was readily formed from pyrene in the absence of light irradiation and at low temperature, but DNP was not formed under similar conditions. DNP formation was catalyzed by nitric acid. The formation of DNP is dependent on light irradiation, temperature and HNO3 as catalyst. In a combustion source these factors affect the formation of DNP.

The Mutagenicity of Refuse Leachate from a Municipal Incinerator.

The mutagenicity of refuse leachate from a municipal incinerator was studied by liquid rec-assay and Ames assay. Volatile components were found to be negative, and nonvolatile components positive, in the Ames assay and the leachate was found to have DNA-damaging capacity in the liquid rec-assay with S-9 mix. PAHs derived from tobacco ash and carbonyl compounds generated by the putrefaction of foods were confirmed to be main contributors to DNA-damaging capacity and mutagenicity in refuse leachate.