Fine sand of less than 60 mesh in size collected from the sandboxes of 40 urban parks throughout the country was subjected to methanol extraction. The mutagenicity of the extract was then measured by the Ames (pre-incubation) method. Most of the samples exhibited mutagenicity, which varied in severity, by four orders of magnitude from the lowest to the highest. The study also indicated that mutagens such as those detected in the TA98 or YG1024 strain existed. High mutagenicity was observed under the condition where S9mix was not added, which suggested that contamination due to direct mutagens was worsening in the sandboxes in parks. By region, mutagenicity tended to be higher in highly populated regions with much industrial activity such as the Kanto area.

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Measurement of acrolein and other aldehydes in ambient air was carried out at the Research Institute of Environment, Agriculture, and Fisheries in Osaka city from May 11 to 19 in 2007. The aldehydes were collected as their derivatives of O-(4-cyanoethoxbenzyl) hydroxylamine (CNET), and determined by liquid chromatography/tandem-mass spectrometry (LC/MS/MS). The concentrations of acrolein, 0.04∼0.49μg/m³, showed the positive correlations with nitrogen monoxide (NO), nitrogen dioxide (NO₂), nitrogen oxides (NO_x), carbon monoxide (CO), and non-methane hydrocarbons (NMHC). On the other hand, it showed the negative correlation with oxidant (O_x). These results suggested that acrolein exhausted from motor vehicles, increased in the morning and midnight, and was easily decomposed under sunlight by photochemical reaction.
Formaldehyde showed a different behavior from acrolein. It showed the positive correlation with oxidant (O_x) generated with the photochemical reaction, and thus increased in the daytime.

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The persistent and hazardous nature of some legally regulated dioxins, including PCDD/Fs and dioxin-like PCBs, makes them of particular concern. However, it is currently not possible to estimate the potential risk of exhaust gases and to act on dioxin measurement data taken in real time at incineration plants, since obtaining results from samples takes time. This study investigates the potential for real-time measurement of organic halogens using atomic emission spectrometry employing radio-frequency helium plasma. Investigations were conducted on the adsorption characteristics of various graphite-based dioxin adsorbents, the basic dose-response relationships of this detection system, and actual gas sampling/measurement using a continuous gas sampling apparatus. The following results were obtained. i)The relationship between halogen amount ratio and peak area ratio using chlorobenzene and bromobenzene as standard compounds showed good linearity. The coefficients between the two parameters varied from 0.66 to 1.4, averaging 1.0. ii)The Carbotrap C tube collected compounds with a boiling point above 180°C; addition of a Carbopak X tube made it possible to collect a wide range of gaseous organic halogens.
The gas sampling tube was incorporated into a semi-continuous sampling apparatus and used for flue gas sampling at actual incineration plants. The sum of the concentrations of organic chlorines and bromines during two five-day measurement periods varied from 0.61 to 9.4μg/m³. This rapid and easy measurement method of organic halogens thus has considerable potential for the management of hazardous substances at incineration plants.

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Influence of solution temperature and acidic surface factional groups on lead(II) ions adsorption onto activated carbons (ACs) were studied. ACs with no surface oxygen, OG-ACs were made by heating at 1273 K under helium flow, and those introduced acidic surface factional groups were prepared with nitric acid, Ox-ACs. The amount of proton released from carbon was measured after the lead(II) ions adsorption was completed. Adsorption of lead(II) ions onto OG-ACs were caused by electrostatic interaction between Cπ electrons on the graphene layer and lead(II) ions, whereas the adsorption onto Ox-ACs were took place by ion exchange. The thermodynamic parameters such as Gibbs free energy change (ΔG⁰), enthalpy change (ΔH⁰), and entropy change (ΔS⁰) were calculated from van′t Hoff plots. Adsorption onto OG-ACs resulted in spontaneous and exothermal process. Though the adsorption by Ox-ACs was also spontaneous from ΔG⁰, the ΔH⁰ was nearly equal to zero because temperature dependence could not be observed for the adsorption onto oxidized carbons. The adsorption kinetics was examined using the Langmuir type rate equation, indicating that adsorption rate constants were greater for Ox-ACs than for OG-ACs. The adsorption kinetic constants were significantly enhanced with increasing solution temperature and/or decreasing in particle size, revealing that the rate determining step of adsorption onto Ox-ACs could be effectively shifted from inter-particle diffusion to collision between adsorbate and adsorption sites.

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A simple pretreatment of sample and comprehensive analysis method has been developed for the GC/MS determination of 29 pesticides in fish and shellfish. For the pretreatment, the pesticides in the sample were extracted with acetonitrile and the lipid in the sample extract was eliminated by partitioning between hexane and acetonitrile. After Sep-Pak Plus Florisil or Florisil PR column clean-up, the sample extract was analyzed by GC/MS (SIM). Recovery tests were performed by use of Sep-Pak Plus Florisil and Florisil PR for fish and shellfish. On the whole, recoveries (%) and CV (%) by Florisil PR were better than those by Sep-pak Plus Florisil in both of Japanese smelt (fish) and corbicula (shellfish). However, Sep-Pak Plus Florisil had better results in pyrokiron, fenthion, etc., so selection of clean-up procedure in agreement with the purpose was recommended. The quantification limits were 0.002∼0.005μg/g for most of the 29 pesticides.

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