Kyohei Yamaguchi

The association between serum levels of Th cytokines and rhinoconjunctivitis caused by methyltetrahydrophthalic anhydride

Background There are few epidemiologic studies on the association between serum levels of T helper (Th) cytokines and allergic symptoms caused by sensitizing agents.

Study on Allergic Rhinitis in Workers Exposed to Methyltetrahydrophthalic Anhydride

Methylterahydrophthalic anhydride (MTHPA) is used as a hardening agent in an epoxy resin system. Because work-related nasal symptoms were observed in some workers exposed toMTHPA at two condenser plants, a cross-sectional survey was performed to improve their work environment. MeanMTHPA levels in the manufacturing processes to which the workers were routinely assigned were extremely low (1.09-22.4 μg/m3). However, specific IgE antibody (S-IgE) was detected in 9 (32%) of 28 workers. Of these, 8 (89%) had nasal symptoms. An IgE-mediated mechanism seems to be associated with at least some of the cases of work-related nasal symptoms. This indicates that the occupational health administration ofMTHPA cannot be controlled simply by limiting exposure in the work environment. Total IgE (T-IgE) levels were significantly higher in S-IgE-positive workers than in S-IgE-negative workers (geometric mean, 200.5 and 51.3 IU/ml, respectively; p<0.002, unpaired t test). These findings demonstrate that workers in whom S-IgE is less likely to be produced, i.e., those in whom the T-IgE level is 80 IU/ml or less, should be assigned to work in these manufacturing processes.

The relationship of lifestyle factors, personal character, and mental Health status of employees of a major Japanese electrical manufacturer

SummaryTo examine the relationship lifestyle factors, personal character, mental health status, and job strain a self-administered questionnaire survey was conducted among employees of a leading electrical manufacturing company in Japan. A total of 2,327 workers (Male=1,668, Female=659) responded to the survey. We analyzed the relationships of health practices based on such factors as: Free child (FC) from the Egogram, the Working-life satisfaction, and the General Health Questionnaire-28 through Path-analysis techniques.The following results were obtained: The mental health status was significantly affected by such factors as health practices, Working-life satisfaction, personal character (FC), life satisfaction, and age. Health practices and personal character (FC) showed a direct relationship to the mental health status and an indirect relationship to the Working-life satisfaction and life satisfaction. The variances accounting for mental health status were 41.8% in male workers and 43.8% in female workers.Path-analysis data suggested that mental health status was affected about 40% by lifestyle, personal character, Working-life satisfaction, and life satisfaction. It was suggested that there might be important factors affecting mental health status but which are unknown to us by as much as 60% in the present day. These findings suggested the necessity of further investigation of the relationship among lifestyle factors, mental health status, and job strain among employees of a reputable company in the present day.

Association of smoking with other lifestyle factors and mental health status of Japanese factory workers

A self-administered questionnaire survey was conducted among factory workers in Japan. The questionnaire included items concerning eight health practices recommended by Morimoto and the General Health Questionnaire-28. Data from 1598 male workers were analyzed. There were few differences in comprehensive health status due to smoking status, but smokers under the age of 30 years had worse lifestyle habits than nonsmokers with regard to favorable drinking and eating breakfast, and smokers between the ages 30 and 44 years had worse lifestyle habits with regard to favorable drinking and eating breakfast, and better habits regarding sleeping hours and working hours. Smokers under 30 showed worse mental health status than ex-smokers with regard to social dysfunction, though there was little difference between those aged from 30 to 44 and those 45 and older. The results suggested the importance of considering the difference in lifestyle and mental health status due to smoking status when providing advice for improving health habits.

Biological Monitoring of Inorganic Mercury in Workers in a Fluorescent Lamp Plant.

Biological Monitoring of Inorganic Mercury in Workers in a Fluorescent Lamp Plant. Masako Iden, et al. Matsushita Electronics Corp., Okayama Factory—The level of mercury in urine is measured as an exposure monitoring of mercury, and the activity of urinary N‐acetyl‐β‐D‐glucosaminidase (NAG) is used as an index of adverse effects of mercury on human kidneys. Here we examined the validity of these procedures by comparing the urinary total mercury (U‐Hg) level and NAG activity in both 75 male workers exposed to inorganic mercury and age‐matched unexposed male workers in a fluorescent lamp plant. To investigate factors affecting the levels of U‐Hg, 12 items were selected in relation to oral intake and excretion of mercury: consumption of 1) soft drink, 2) coffee or tea, 3) milk and 4) alcohol; 5) habit of drinking tap water at the work place; frequency of 6) eating fish and 7) alcohol intake; 8) smoking; 9) use of dental amalgam; 10) eating of home grown rice; 11) exercise habit and 12) age. The U‐Hg level and NAG activity were adjusted by creatinine levels. Personal exposure levels of inorganic mercury in air (A‐Hg) and the U‐Hg level correlated well (p< 0.001) in the exposed group but neither the exposed nor unexposed group showed a correlation between the U‐Hg level and NAG activity. Although the mean level of U‐Hg in the exposed group was higher than that in the unexposed (p< 0.001), no difference was observed in the mean level of NAG activity. A multiple regression analysis followed by a one‐way ANOVA revealed that only the frequency of eating fish per week contributed to increase the level of U‐Hg. The results suggest that oral intake of mercury from fish is a possible confounding factor in the exposure monitoring of inorganic mercury in the work place.

ヘッドスペース・ガスクロマトグラフ(HS・GC)法による尿中アセトン,メタノール,およびメチルエチルケトンの定量

Using HS.GC, We have succeeded in simultaneous determination of Ac, MeOH and MEK in urine without any complicated pretreatment or correction by internal standard. Moreover, in order to lower the detection limits of these materials, study was made on the salting out effect using 14 kinds of salts. As pretreatment, 2.0 ml of urine, 3.0 g of sodium sulfate and small sized magnetic stirrer are put into vial, which is sealed by septum. This is then heated for 10 min in warm bath of 50 degrees C. In order to dissolve the added salts as much as possible, the specimen is stirred by the stirrer. After cooling the liquid to room temperature, the specimen is analysed by HS.GC. The results showed that sodium sulfate was excellent synthetically. 1) Using the urine of workers not exposed to organic solvents three kinds of urine having specific gravity of 1.010, 1.024 and 1.034 were prepared and mixed standard organic solvents (Ac, MeOH and MEK) were added. Recovery percentages and coefficients of variation were calculated. The results showed that recovery percentages ranged from 92.0 to 101.7% and coefficients of variation from 0.2 to 4.6%. 2) The regression equations of standard curves were satisfactory with y = 9053x - 200(r = 0.999, n = 12) for Ac, y = 801x - 400 (r = 0.999, n = 12) for MeOH, and y = 15488x - 277 (r = 0.999, n = 12) for MEK. 3) The detection limits calculated by IUPAC formula were 0.0092 mg/l for Ac, 0.11 mg/l for MeOH and 0.0063 mg/l for MEK. These results indicated that this method is superior to other methods because the pretreatment is very simple, specificity is excellent, analysis by standard curves is possible, and this method is not affected by specific gravity of the urine.