Nitrogen dioxide is known to be an air pollutant inducing photochemical smog, in which reactive species such as an oxygen atom O (³P), ozone and hydroxyl radical etc. could take part in its appearance. Aromatic hydrocarbons released from automobiles into the troposphere underwent a ring fission leading to glyoxals (α-diketones) and the hydroxyl-nitration of the ring leading to nitrophenols under the circumstances. Their formation could be attributed to the action of the above active species. Moreover, α-diketones or suspended particulates, one of air pollutants, caused the photo-epoxidation, for example, converting aldrin into the corresponding epoxide, dieldrin.

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Mercury pollution due to gold mining activities in Amazonian region has become a matter of worldwide concern in recent years. To assess the extent of mercury pollution and its health effects, the four years'collaborative study between our Institute and Federal University of Rio de Janeiro has been started in 1992 as a part of Global Environmental Research Project in the Environment Agency of Japan. This paper outlines the results of our preliminary study on mercury pollution mainly in Tapajos river basin, where can be considered the oldest and most productive gold mining area in Amazon. Human hair and blood as well as fish samples were collected from gold mining area and five fishing villages and analyzed for total mercury and methylmercury with new methods recently developed in our laboratory. The results to date showed that the inhabitants of fishing villages near gold mining area were more exposed to methylmercury than those far from gold mines. A few hair samples tested had methylmercury levels greater than 50 ppm, the minimum threshold value for methylmercury poisoning. Analysis of hair samples from gold miners and workers in gold shops showed that they were mainly contaminated with inorganic mercury. From these analytical results, together with mercury analysis in fish as well as human blood samples, the mercury pollution mechanisms in the study area are also discussed.

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In 1993, ICP (inductively coupled plasma) spectrometry and ICP/MS (mass spectrometry) were adopted by the Water Works Law and by the Basic Environmental Preotection Law for as offical methods for determining metals in water. The elements of water quality standards are aluminum, boron, cadmium, chromium, copper, iron, lead, manganese, molibdium, nickel, sodium and zinc. An ICP spectrometer has a mono-, polychrometer detection system and a sequential detection equipment, as well as characteristic functions such as simultaneous multi-elemental analysis. The linear dynamic ranges are four to six orders of magnitude for many elements and low detection limits for many elements. ICP/MS can also perform simultaneous multi-elemental analysis, and shows greater high sensitivity and less interference compared with an ICP spectrophotometer. The ICP and ICP/MS spectrometers, their principles, the function of the apparatus, interferences and applications to water and food analyses are described.

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To determine the nitrogen dioxide level in indoor air as one of the many harmful atmospheric pollutants, a total 200 sampling locations in Seoul and its suburbs were selected. A Palmes tube based upon Fick's 1st law of passive diffusion was used for gaseous nitrogen dioxide absorption. Atmospheric nitrogen dioxide diffuses through the tube and forms a stable complex with triethanolamine coated on a stainless steel screen in the tube. This complex was spectroscopically analyzed by adding a coloring reagent. The average nitrogen dioxide level obtained from 200 sampling locations in Seoul and its suburban areas investigated over 3 seasons, was 60.22 ppb with the range of 43-79 ppb. The nitrogen dioxide level tended to accumulate in the winter. The relationship between nitrogen dioxide in the level and the type of business or fuel, differences in the amount of fuel consumed and facility of ventilation are discussed.

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In order to estimate the effectiveness of sodium dichloroisocyanurate (SDI), an effervescent disinfectant tablet, for general disinfection use at medical facilities, its antimicrobial activities against various organisms, including hepatitis B virus, and its chemical stability were studied by comparing it with those properties of sodium hypochlorite (SHC). Solutions of SDI and SHC containing 100 ppm, 500 ppm and 1000 ppm available chlorine (av. Cl) showed equivalent activity against vegetative bacteria, Mycobacteria, fungi and bacterial spores. Virucidal action required a higher concentration of both disinfectants : 1000 ppm av. Cl of SDI and SHC did not inactivate hepatitis B surface antigen (HBs-Ag) in 60 min, whereas 5000 ppm av. Cl of both disinfectants inactivated HBs-Ag in 3 min at 25°C. Although solutions of SDI and SHC were relatively stable for 24 h under clean conditions, both solutions markedly decomposed in the presence of human serum. In the presence of 30% human serum, 10000 ppm av. Cl of SDI and SHC decomposed to approximately 6600 ppm and 2600 ppm, respectively, immediately after preparation at 25°C. Based on these results and the simplicity of preparation of dilutions for use, SDI is considered to be a useful disinfectant for use in medical facilities.

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Effects of cholecystokinin on metallothionein in mice were studied. The total amount of metallothionein in the mouse pancreas increased after the injection of cholecystokinin. The increase was dose-dependent and a positive relationship was observed between amylase activity in the serum and the total amount of metallothionein in the pancreas. A pre-injection of zinc, cadmium or benzene depressed the increase of the serum amylase activity after the injection of cholecystokinin. In the case of pre-induced MT, a negative relationship was found between metallothionein concentration in the pancreas and amylase activity in the serum. These results indicate that the metallothionein concentration in the mouse pancreas increased after the injection of cholecystokinin, and suggest that metallothionein in the pancreas may protect the pancreas against acute pancreatitis caused by cholecystokinin.

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The method for the automatic analysis of methamphetamine (MA) and amphetamine (AP) in the urine was developed using a prepstation in combination with a GC/MS instrument. A prepstation can automate many pretreatment steps, such as solid phase extraction (SPE) and derivatization. Human interaction is only required to load the urine samples into vials, cap them and place them on the auto sampler tray. All of the following steps were automated : 1) An urine sample of 1.5 ml was injected into the SPE cartridge (DAU), where MA and AP were retained. 2) The cartridge was then washed with 1M acetic acid (1 ml) and then with methanol (3 ml). 3) The MA and AP were then eluted using 0.1% sulfric acid-methanol (0.5 ml) from the washed cartridge. 4) The elute was evaporated and dried. Then a 4N sodium hydroxide (0.02 ml) and a 10 ppm diphenylmethane in dichlormethane (0.2 ml) internal standard (I.S.) solution were added and stirred. 5) A derivatizing reagent, N-methyl-bis-trifluoroacetamide (MBTFA) was added into the sample. 6) And finally, the reaction mixture was injected into the GC/MS instrument for analysis. The total analysis time for 10 samples was approximately 10 h and 20 min. The calibration curves, using the I.S. method, demonstrated good linearity throughout the concentration range from 0.1 to 10 μg/ml for both MA and AP. Using a scan mode the detection limits were 20 ng/ml for both MA and AP and using selected ion monitoring (SIM) the limits were 1 ng/ml for MA and 3 ng/ml for AP. The relative standard deviation using the scan mode for a 1 μg/ml sample was 5.9% for MA and 6.0% for AP.

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Rubber particles emitted by abrasion of automobile tire tread have caused environmental pollution, and may be hazardous to our health. In this study, airborne particulate samples were collected on the glass fiber filter using high-volume air sampler at the roadside of the 2-nd Shinmei highway in Kobe. Rubber particles in the roadside atmosphere were analyzed by pyrolysis gas chromatography. The concentration of rubber particles was estimated from the total amount of styrene and isoprene, because these two compounds are pyrolysates of styrene butadiene rubber and natural rubber which are main materials for tires. These concentrations were 0.5-10.5 μg/m³, which corresponded to 0.4-6.3% of total airborne particulates. These concentrations were higher than those in other reports, because the sampling point was the roadside of the highway in this experiment. Furthermore quantitative and qualitative analyses of rubber additives (Zn-DMDTC and IPPD) in airborne particulates were carried out by HPLC, GC and MS. Zn-DMDTC, after converted into Co-DMDTC, in airborne particulates was analyzed by HPLC. The concentrations of Zn-DMDTC were 0-5.1 pg/m³. The detected amount of Zn-DMDTC did not show mutagenic activity. However, in the case of long term exposure to these tire tread particles, we must take a hazardous effect by Zn-DMDTC into consideration. On the other hand, IPPD was confirmed in none of samples by GC and MS.

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We studied the binding between bovine serum albumin (BSA) and methamphetamine (MAMP) with the ultra filtration method. Under the conditions employed by this study, the reaction requires the incubation for 18h at 37°C to be equilibrated. The pattern of Scatchard plot of the binding reaction between BSA and MAMP was biphasic. The results suggest that BSA had two binding sites for MAMP ; the binding constant and the maximal binding of MAMP to BSA in classes I and II bindings were 216.9×10³ M^-1 and 0.2, and 0.1×10³M^-1 and 14.9, respectively.

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Suspended particulate matter (SPM) levels in air samples collected with a high-volume air sampler from the Kobe area in Japan were measured. Furthermore, the evaluation of the source apportionment to SPM was investigated by the chemical mass balance (CMB) method based on nine elements, i.e., Ca, K, Na, Fe, Mn, Al, Ni, Zn and V, as an index element. The sum of the percent contributions to SPM from six main sources (soil, marine, fuel oil combustion, iron-and-steel industry, refuse incineration, cement particles) was calculated to be about 25%. Among these sources, fuel oil combustion showed the largest contribution.

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This paper describes the results concerning the effects of various disinfectants on the oxygen uptake rate (OUR) of activated sludge (AS). To start with, in vitro inhibitory effects of four test disinfectants : STERIHYDE^[○!R], HYAMINE-T^[○!R], ISODINE^[○!R] and HYPAL No.20^[○!R], on OUR of two kinds (AS-A ; Kamaboko fishcake industrial waste water and AS-B ; local municipal sewage) of AS were determined by the previously mentioned method. The IC₅₀ values of thirty-three kinds of typical disinfectants were measured for AS-A, respectively. GRINCE^[○!R], termed 2, 4, 4'-trichloro-2'-hydroxydiphenyl ether (0.3% Irgasan DP 300), and Irgasan DP 300 alone, inhibited most strongly by the IC₅₀ values of 6 mg/l, respectively, and followed by Cetylpyridinium chloride (20 mg/l), OSVAN^[○!R] (58 mg/l), HYAMINE-T^[○!R] (58 mg/l), Potassium permanganate (60 mg/l), Thimerosal (65 mg/l) and Benzethonium chloride (80 mg/l). However, with Phenol, Suponated cresol, Resorcin, Silver nitrate, Medical soap, Bronopol and Acrinol, the concentration of these disinfectants which results in the IC₅₀ value were over 1000 mg/l. In addition, the toxic effects on OUR of AS in the presence of an equivalent mixture of two disinfectants tend to become stronger than that of the disinfectant alone. Namely, the additive effects of OUR-inhibition seemed to exist (For example ; Saponated cresol-STERIHYDE^[○!R], HIBITANE^[○!R]-GRINCE^[○!R] etc.).

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