Methods for the qualitative analysis and determination of antimicrobial agents in fabrics are described. At present, antimicrobial agents mainly used are 2, 4, 4'-trichloro-2'-hydroxydiphenyl ether (Irgasan DP300), 3-(trimethoxysilyl) propyldimethyloctadecyl ammonium chloride (DC5700) and thiabendazole (TBZ). The procedure of qualitative analysis is as follows : (1) DC-5700 in fabrics is checked by the adsorption of bromophenol blue (BPB) on the strips packed in column. (2) Irgasan DP300 eluted with ether from fabrics is detected by Gibbs reagent on silica gel thin layer chromatography (TLC). (3) TBZ is eluted with methanol from the fabrics after the ether-elution and detected by UV 254 nm after spraying sulfuric acid on silica gel TLC. DC-5700 is determined from the amount of 1-octadecene, formed in Hofmann degradation, measured by gas-liquid chromatography (GLC). The determination of Irgasan DP300 in fabrics is carried out by high performance liquid chromatography (HPLC) on the acidic fraction of extract with methanol : acetic acid (9 : 1) under reflux and TBZ is determined by GLC on the alkaline fraction of the abovementioned extract. By using the qualitative and quantitative system, Irgasan DP300, DC-5700 and TBZ were detected in 12, 4 and 2 samples, respectively, of 23 commercial fabrics treated with antimicrobial agents.
A method for the quantitative determination of oxine-copper [bis (quinolin-8-olato) copper], a fungicide used widely in golf links, in water was developed. Oxine-copper was extracted from the sample water with dichloromethane. The dichloromethane solution was evaporated to dryness. The residue was dissolved in methanol and the solution analyzed by high performance liquid chromatography. The analytical conditions were as follows : column, Inertsil ODS-2 equipped with ceramic filter (GL Sciences, 5 μm, 250 mm×4.6 mm i.d.) ; mobile phase, acetonitrile-50 mM phosphate buffer [pH 3.5, containing 0.1% ethylene-diaminetetraacetic acid disodium salt] (EDTA-2Na) (40 : 60, v/v) ; flow rate, 0.8 ml/min ; detection wavelength, 240 nm. Under these conditions oxine-copper was converted to 8-hydroxyquinoline by EDTA added to the mobile phase, and the resulting 8-hydroxyquinoline determined quantitatively. The calibration curve for oxine-copper was linear in the range of 1-100 ng. The minimum detectable amount of oxine-copper was 0.1 ng. This method is widely applicable to the determination of trace amounts of oxine-copper in water.
Indoor air pollution by chlorpyrifos and S-421 applied to building timbers for the control of termite was studied. Chlorpyrifos and S-421 in indoor air were adsorbed on silica gel by suction using a diaphragm air pump, eluted with 50 ml of acetone and determined by gas chromatograph-mass spectrometry. Chlorpyrifos and S-421 levels in indoor air ranged from 0 to 0.258 and from 0.012 to 0.174μg/m3, respectively and tended to be higher in summer with a rise in atmospheric temperature than those in other seasons. Chlorpyrifos and S-421 levels in the air of the Japanese-style room are higher than those of the wash room. The chlorpyrifos and S-421 levels were found to decrease by the use of a ventilator.
The level of radioactive cesium (the sum of (134)cesium (Cs) and (137)Cs) was investigated in total diet samples collected from adults living in the Sapporo area, Hokkaido. They were ashed, and examined with a germanium semiconductor detector. The maximum and average radioactivities of cesium in an indivividual's daily food intake were as follows: 1.0 Bq and 0.24 Bq in July 2011, 1.3 Bq and 0.30 Bq in November 2011, 3.9 Bq and 1.0 Bq in February 2012, and 0.34 Bq and 0.12 Bq in July 2012, respectively. The committed effective dose would be 0.022 mSv/year in the case of continued intake of meals containing the maximum cesium concentration.
