We have examined a screening method for detecting formaldehyde emitted from textile products using a developed formaldehyde-sensing element. We propose two methods. With one method, we measure the amount of formaldehyde emitted from undamaged clothes that had been placed in a package with the developed sensor element. With the other hand, we measure the amount of formaldehyde emitted from clothes that had been cut up and placed in a container with the developed sensor element. We compared the results obtained using these two methods with results obtained using the JIS method (L1041). We found that the determination coefficients for the L1041 method and the two methods were 0.96 and 0.77, respectively, indicating good agreement. We also found that we could carry out a temperature correction of the absorbance values obtained with the two methods. The first method, where we are able to use undamaged clothes without the need to cut them up, would be an effective screening method, because it requires no special procedure, and we can easily estimate the amount of formaldehyde emitted from the clothes simply by placing the sensor element in the package for 1 hour.

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The high performance bamboo charcoal for humidity control was prepared by carbonization with an agent of potassium compound. The mixture of potassium carbonate and raw bamboo chip with the mass ratio (K₂CO₃/Bamboo ratio) of 0.05, 0.1 and 0.5 was carbonized at 500 °C with heating rate of 25 °C /min under nitrogen flow for 2 hours using a tubular furnace. The surface area and the pore volume were measured with BET, α_s -plot and t-plot method, and surface functional groups were determined by Boehm titration. The results showed that the surface area was varied according to the K₂CO₃/Bamboo ratio. The surface area of bamboo charcoal with the low K₂CO₃/Bamboo ratio was smaller than that of original bamboo charcoal of 250 m²/g. However, the high K₂CO₃/Bamboo ratio resulted in the increase in the surface area of 472 m²/g, which was much larger than original bamboo charcoal. The amount of surface functional groups increased with the existence of K₂CO₃, and especially the carboxyl group greatly increased. The result of water vapor adsorption-desorption experiment for each prepared bamboo charcoal revealed that the charcoal with high amount of functional groups could uptake water vapor at low humidity region, while high amount of water vapor adsorption was observed for the charcoals possessing high pore volume content at medium-high humidity region. The water vapor adsorption- desorption experiment as a function of temperature was also performed assuming the seasonal temperature variation. The amount of water vapor adsorption-desorption did not depend on the sorts of bamboo charcoals. Accordingly, the bamboo charcoal carbonized with an agent of potassium compound could be expected as a superior humidity control material, which was hardly affecterd by seasonal temperature variation.

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In conventional monitoring of dioxins (PCDDs, PCDFs, and dioxin-like PCBs) in ambient air in Japan, the average of TEQ concentration in four samples obtained by one solid week sampling in each season (TEQ-S) is regarded as the annual average. The TEQ in the ambient air depends on meteorological conditions and human activities. Due to assess the annual average of TEQ concentration based on four data points, it is necessary to know the accuracy of TEQ-S comparing with the actual annual average from over 50 weeks. In this study, we continuously measured dioxins in the ambient air in Kazo-city (the northeastern part of Saitama prefecture) from December 2006 to March 2010 (3 years and 3 months) collected by one solid week sampling. The TEQs in the ambient air ranged from 0.030 to 0.51 pg-TEQ/m³, which is below the environmental standard value of 0.6 pg-TEQ/m³. The TEQs showed seasonal changes, which tend to be higher in winter and lower in summer. Ninety five % (2.5-97.5 percentile) of TEQ-S ranged in 0.5-2.0 times of the actual annual average. Moreover, we found the concentration of TEQ-S was lower than the actual annual average in many cases. This indicates that the ambient air dioxins should be assessed with considering of which there is a possibility that TEQ-S might be a half of the actual annual average in variation. The actual annual average during the sampling period showed the tendency to decline slightly.

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A rapid and simple analysis of dieldrin in soil using ultrasonic extraction was investigated. The results were as follows. Dieldrin in soil could be extracted with acetone without air-drying of soil. Ultrasonic frequency at 45kHz showed relatively high extractability and good reproducibility of dieldrin in soil. Temperature of extraction solution during the period of ultrasonic extraction effected on extractability of dieldrin in soil; Its optimum temperatures were 50 °C for the total dieldrin extracted with acetone and 10 °C for the phytoavailable dieldrin extracted with 50 % MeOH / water. Based on these optimum condition of ultrasonic extraction, we can measure total and phytoavailable dieldrin in soil at short time of analysis.

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The concentrations of Biochemical oxygen demand (BOD) and ammonium nitrogen in river waters is returning to the early 1960s, but potassium permanganate consumption and total organic carbon (TOC) concentrations does not return. It is thought that their cause comes from the not decreasing of the refractory dissolved organic matter. It seems that refractory dissolved organic matter in raw water is originated from treated water of wastewater treatment plant.
These organic compositions of hydrophobic organic matter and hydrophilic organic matter in refractory dissolved organic matter are not elucidated.

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