| Budget Amount *help |
¥5,000,000 (Direct Cost: ¥5,000,000)
Fiscal Year 1992: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1991: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1990: ¥3,900,000 (Direct Cost: ¥3,900,000)
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| Research Abstract |
Two of diffusive personal samplers have been successfully developed. One type takes advantage of 2 plastic disposable injection syringes (2.5 ml). One syringe is cut at 2 cm from the brim. Two brims are put together with porous membrane (Cellpore<@D1(] SY.encircledR.[)@>D1 NW-11) between them. Redistilled water, 2ml, is taken into the syringe, and water is exposed to ambient air through the membrane by keeping the needle joint part upward. In the case of the other sampler, silica gel A (20 to 30 mesh, 1.2 g) is taken into a phi 9 mm X 50 mm in length plastic cylinder. One end of the syrinder is closed, and the other end has a phi 5.7 mm window covered by the porous membrane. Solvent vapor exposure chambers of dynamic flow type was employed for experimental exposure. Exposure of water-equipped samplers to acetone vapors at up to 1000 ppm for up to 8 hours, or methanol vapors at up to 4000 ppm for up to 8 hours showed that the amount of solvent absorbed was proportional to the multiplication of the exposure concentration and exposure duration (i.e., CxT). Recovery after 15 min exposure at the maximum concentrations showed that the recovery was better than 80%. Similar exposure of silica gel-equipped samplers to methyl acetate vapors at up to 1600 ppm for up to 8 hours also showed that the amount adsorbed was proportional to CxT. Short-term peak exposure at 1600 ppm for 15 min showed a recovery of 108%. The experiments as a whole indicate that the water-equipped samplers can be applied for the monitoring of acetone and methanol vapors, and the silica gel-equipped one for methyl acetate monitoring in occupational health.
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