Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonate (PFOS) as persistence organic pollutants (POPs) have been detected in environmental waters around the world. However, only few information on PFOA and PFOS in the Thai environment has been obtained. In order to clarify the pollutions of PFOA and PFOS in waters of lakes and seaside areas in Thailand, we analyzed PFOS and PFOA with SPE-LC/MS in water samples in Kasetsert University in Bangkok, Thailand. However, commercial methanol and RO water for LC/MS analysis purchased from chemical companies in Bangkok were contaminated with PFOS and PFOA before use. The contaminants in the solvent and the commercial pure water were removed using a mix-mode anion exchange solid-phase extraction cartridge (OASIS MAX, Waters). PFOS and PFOA were detected from all samples at the ranges between 0.8 and 61.7 ng/L and between 10.0 and 29.0 ng/L, respectively. It should be noted that the molar ratios of PFOS and PFOA in the East-side and the West-side of the Thai Gulf were different. The finding suggests that the pollutants in the both sides might be drained from different sources.

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Concentrations of sixty-four kinds of pesticides in Shinano and Agano River waters and tap waters produced in Aoyama and Shinanogawa water treatment plants (WTP) in Niigata city were monitored twice a week from April 2007 to April 2008. The maximum and average amounts of each pesticide were made clear. The presence of pesticides in the river water correlated with the time of pesticide application to the fields. The concentrations of pesticides were reduced in the process of the rapid sand filtration systems except dichlorvos (DDVP), though the extent of reduction differed in each pesticide. The concentrations of the pesticides were remarkably decreased by the combination process of the rapid sand filtration and the granular activated carbon absorption process. A study with the same intention and method with that mentioned above was carried out in our laboratory from April 1995 to April 1996. When compared with the 90′s results, both the number and the concentrations of the pesticides were found to be decreased in 2007 and 2008.

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Lead contained in plastic shopping bags was analyzed by X-ray fluorescent analysis. The detection rate of bags which contained lead over 100 ppm was about 17∼18 % of colored bags, 4 % of all bags. Both in 2006 and 2007, average lead concentration was about 310 ppm. Concentration and detection ratio of lead were different according to bags′ color. There were some bags whose lead concentrations were over 10,000 ppm.
The amount of lead in plastic bags which had been thrown away as household waste was estimated to be 0.98∼1.3 tons/year in Kyoto city, which is equivalent to 84∼110 tons/year in all over Japan. Since these bags end up being burned up, it may account for 0.5∼2.0 % or more compared to total incinerated lead in Japan. Also because shopping bags are very popular goods in house, it is desired to decrease lead in bags.

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Although the existence of chemicals having binding affinities for cellular receptors is becoming known and some of them are detected in environmental samples, their multiple abilities cannot be ascertained by individual measurements of chemicals. To enable monitoring of river water quality from effects on receptors, we attempted to measure the receptor activities of river water samples by multiple yeast assays transfected with a cellular receptor and co-activator. Water samples from rivers subjected substantially to treated sewage (such as Tama River located in Tokyo), rivers flowing in overpopulated centers (Sumida River, Kanda River and Meguro River in Tokyo) and rivers with luxuriant algae (Sakura River in Ibaraki) had higher activities to the human and medaka -estrogen receptors, the human aryl hydrocarbon receptor and the human retinoic acid receptor, respectively. Because these receptor activities were not consistent with the results of commonly used methods for water quality monitoring, the yeast assays are expected to provide new perspectives on estimation of influences by receptor effects to quality surveys of environmental waters.

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We researched the adsorption properties of 36 agrichemicals and 14 dioxin-like polychlorinated biphenyls (DL-PCBs) on activated carbons. We examined the adsorption ratio of substrates on activated carbons, and then the influences of chemical structure of substrate, pore structure of activated carbon, and solvent effect for adsorption were studied. These experiments revealed that the substrates having not just higher logPow value than 3 but also aromatic ring with sterically-unhindered substituent groups in its chemical structure showed high adsorption property on activated carbons. It was found that the activated carbon which had the large surface area of micro pores in the diameter of around 0.7-0.8 nm and low functional groups on activated carbon surface, had the high adsorption capacity for substrates. It also became clear that solvent polarity greatly affected to the adsorption proparties and high adsorption ratio were observed in the case of water solution for all substrates.

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An analytical method for the determination of polybrominated diphenyl ethers (PBDEs) in sediment and fish samples has been developed by using a sulfoxide cartridge column as an effective clean-up procedure. After saponification of samples, PBDEs were extracted with hexane. Then the extract was treated with sulfuric acid and frorisil column chromatography. The eluate from the florisil column was loaded on a sulfoxide cartridge column, and then PBDEs were eluted with 20 mL of 10 % acetone/hexane. The measurement of PBDEs was carried out by HRGC-HRMS. By cleaning with a sulfoxide cartridge column, the number of peaks on SIM chromatograms that cause the drop of lock mass signal during GC-MS measurement and interfere with the quantification of PBDEs was dramatically reduced. The developed method was applied to the analysis of certificated reference materials of fish tissue and soil. The results obtained were within the range of certificated values except for 2,2′,3,4,4′,5′,6-heptabromodiphenyl ether (#183).

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In this study, we examined the utilization of washing by ultrasonic waves for reduction of four pesticide residues on surface of strawberry and grape in order to reduce a risk on pesticide residues to consumer. The removal rates was high in the order of acetamiprid, diethofencarb, chlorfenapyr and pyridalyl according to solubility in water. In particular, it was found that appending powderly activated carbon in proper quantity was effective on improvement of removal rate of pyridalyl which is water-insoluble.

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Forty-five compounds of ambient polycyclic aromatic hydrocarbons (PAHs) in particulate matter were examined at an urban location of Osaka, Japan, over the period of one year from April 2001 to March 2002. A comparative survey was performed at a roadside location of Shijonawate, located in eastern Osaka. PAH concentrations at the two locations decreased from spring to summer, and increased in winter. The maximum total PAH concentrations of >100ng m^-3 were observed on 15∼16 January at the both locations. However, the use of automobile with diesel engine, estimated to be main emission sources of PAHs, was almost constant at the roadside location during the measuring period. Total PAH concentrations show negative correlations between ambient temperature, sunshine quantity and wind speed. Therefore, possible causes of the increase in PAH concentrations in the winter season is the enhancement of condensation of low-molecular-weight PAHs onto the surface of PM, the depression of the photolytic degradation and the appearance of atmospherically stable layer. In particular, from an estimation of potential temperature gradient, an abnormally strong stablelayer would form on 15∼16 January, resulting in the significantly high PAH concentrations on that day.

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