|Budget Amount *help
¥5,600,000 (Direct Cost : ¥5,600,000)
Fiscal Year 1997 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1996 : ¥4,700,000 (Direct Cost : ¥4,700,000)
The neurotoxicity of organic solvents is one of the most important emerging issues in the field of occupational health. We conducted several epidemiological survey on the neurobehavioral and psychological effects using different kind of tests for central nervous system, neuroconduction velocity of peripheral nerves, color vision and other neurophysiological tests among Japanese workers who have been exposed to stirene and toluene. The results of pairwise comparison of the neurobehavioral test, performance on the digit symbol test, Santa Ana test and vocabulary test (synonyms) in exposed subject were significantly lower than those of workers. Neurobehavioral performance of those whose cumulative exposure index (CEI) was above 18 was significantly lower than those of Workers. But performance whose CEI was lower than 18 (i.e.50ppm x 18years) not significant with those of the referent group. Multiple linear regression analysis controlling for confounding variables such as age, alcohol cons
umption, smoking habit, education attainment, vocabulary and digit span tests showed that the synonym score were significantly related to the CEI.Both hand-eye motor coordination and reaction time were also significantly related to exposed duration (years). Color discrimination was examined in 79 male workers exposed to stirene and in 42 workers exposed to toluene. Stirene exposure was due to the handling of glass-reinforced polyester materials and toluene exposure in the photogravure printing process. A standardized quesionnaire was adopted to collect work history, data on occupational or nonoccupational solvent exposure, alcohol consumption and drug use. Color vision was evaluated by the Lanthony desaturated panel D-15 test. The results of the test were expressed as the color confusion index (CCI). A significant difference was found between stirene-exposed workers and age-matched referents but not in the study of workers exposed to toluene and their referents. The mean atmospheric stirene exposure concentration was about 20 ppm. The mean urinary concentration of mandelic acid was 0.43g/1 0.58. There was a significant difference in CCI between exposed workers and age-matched controls. Color vision of workers whose concentration of urinary mandelic acid was 0.42g/1 was significantly impaired when compared with workers whose concentration was 0.42g/1. Multiple linear regression analysis that controlled for confounding variables such as age, alcohol consumption, smoking, and educational attainment showed that CCI was signifcantly related to the concentration of mandelic acid. In both exposed workers and controls, the types of defects were mostly blue-yellow loss, although a few subjects showed complex loss. no one showed red-green loss.
トルエン曝露者の尿中馬尿酸濃度は1.50g/gであった。スチレン20ppm以上の曝露者で色覚は有意に劣ったが、トルエン曝露群では有意ではなかった。末梢神経伝導速度も同様の結果であった。トルエン曝露群では、中枢神経障害を検討したが、平均曝露年数は15.1年、累積曝露指数CEIは12.3+7.6年で、Digit symbol,Santa Anaおよび言語では、曝露群は有意に劣った。特にCEIが18(すなわち50ppmで18年以上曝露)郡では、それ以下に比べ有意に対照群との差が認められた。 Less