To establish more accurate equations for estimating the moment arm length and cross-sectional area of the erector spinae and rectus abdominis muscles, the effects of height, weight and age on those muscles were analyzed by using a high-order polynomial equation. Data on the moment arm length and cross-sectional area at L3/4 were obtained from MRI images of 152 males and 98 females. The statistical model used in this study has any combination of up to third-order independent variables for age, height and weight. The effective independent variables were selected by the forward step method of multiple regression analyses. The results of multiple regression analyses showed that the polynomial equations for the moment arm length of erector spinae in both genders, and that for the rectus abdominis in males, contained all three variables of age, height and weight. That for the moment arm length of female rectus abdominis contained the variables of weight and age. The multiple correlation coefficients of the erector spinae and rectus abdominis were 0.355 and 0.650 for males, 0.364 and 0.411 for females, respectively. The equations for the cross-sectional area of the erector spinae in both genders, as well as that for male rectus abdominis contained only one variable (weight). The multiple correlation coefficients of the cross-sectional area of the erector spinae were 0.576 for males and 0.469 for females. The cross-sectional area of the female rectus abdominis had no effective variables.

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The aim of this study was to examine the effects of a stress management program for teachers on their stress responses, social support, and coping. Participants (n=24) were assigned to either an intervention or a waiting list control group. A five-session program, including psychoeducation, group discussion, role-playing and relaxation training, was conducted for the intervention group at two week intervals. Eight participants from each of the groups responded to pre- and post-intervention questionnaire surveys. The positive intervention effect was significant for social support from co-workers (p=0.035), whereas the negative intervention effect was significant for proactive coping (p=0.033). No significant effect was observed for stress responses (vigor, anger, fatigue, anxiety, depression, and somatic stress responses) (p>0.05). The positive intervention effect was marginally significant for social support from co-workers (p=0.085) and anger (p=0.057) among those who at first had high stress response scores in the pre-intervention survey (n=5 and n=4 for the intervention and waiting list control groups, respectively). Furthermore, the positive intervention effect was significant for social support from co-workers (p=0.021) and marginally significant for resignation coping (p=0.070) among those who at first had high job control scores (n=4 and n=5 for the intervention and waiting list control groups, respectively). Results showed that the stress management program conducted in this study contributed to increasing social support from co-workers. This study suggests that a program that focuses on a particular subgroup (e.g., those with high stress responses or high job control) might be effective in enhancing coping skills, increasing social support, and reducing stress responses.

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To estimate the critical dose of the association between the blood lead concentration (BPb) and δ-aminolevulinic acid (ALA) levels, ALA levels in plasma (ALA-P), blood (ALA-B), and urine (ALA-U), and the activity of δ-aminolevulinic acid dehydratase (ALAD) were determined in 186 Japanese lead workers, aged 18-62 yr, with BPb levels of 2.1-62.9 g/dl. For this purpose, the benchmark dose (BMD) method, recently used in the environmental health field in place of the no-observed-adverse-effect level, was introduced into this study. The BMD was defined as the BPb level that resulted in an increased probability of abnormal change in ALA-related parameters by an excess risk (BMR) of 5% in exposed workers i.e., from P₀ (abnormal probability of 5% in unexposed workers) to P₀+BMR for exposed workers at the BMD. ALA-related parameters were significantly correlated with BPb. The BMDs computed from the 186 workers, after controlling for age, were 15.3-20.9 g/dl for ALA levels, and 2.9 g/d l for ALAD; likewise, the BMDs from the 154 workers with BPb levels of less than 40 g/dl were 3.3-8.8 g/d l for ALA levels, and 2.7 g/dl for ALAD. Since the cutoff value of ALA-P, computed from the latter workers, seems to be closer to the upper normal limit in unexposed adults than does that from the former workers, it is suggested that the critical dose of BPb causing the increased levels of ALA is below 10 g/d l. Such critical doses are necessary to promote preventive activities of adverse effects of lead.

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Ethanol (ETOH) is added to unleaded gasoline to decrease environmental levels of carbon monoxide from automobiles emissions. Therefore, addition of ETOH in reformulated fuel will most likely increase and the involuntarily human exposure to this chemical will also increase. This preliminary study was undertaken to evaluate the possible neuromotor effects resulting from acute ETOH exposure by inhalation in humans. Five healthy non-smoking adult males, with no history of alcohol abuse, were exposed by inhalation, in a dynamic, controlled-environment exposure chamber, to various concentrations of ETOH (0, 250, 500 and 1,000 ppm in air) for six hours. Reaction time, body sway, hand tremor and rapid alternating movements were measured before and after each exposure session by using the CATSYS^TM 7.0 system and a diadochokinesimeter. The concentrations of ETOH in blood and in alveolar air were also measured. ETOH was not detected in blood nor in alveolar air when volunteers were exposed to 250 and 500 ppm, but at the end of exposure to 1,000 ppm, blood and alveolar air concentrations were 0.443 mg/100ml and 253.1 ppm, respectively. The neuromotor tests did not show conclusively significant differences between the exposed and non-exposed conditions. In conclusion, this study suggests that acute exposure to ethanol at 1,000 ppm or lower or to concentrations that could be encountered upon refueling is not likely to cause any significant neuromotor alterations in healthy males.

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Systemic effects of p, p'-DDE (1, 1-dichloro-2, 2 bis (p-chlorophenyl) ethylene ; DDE) on immature male rats were investigated in pubertal Wistar rats after oral administration of DDE. Special rat chow containing 125 ppm DDE (approximately 10 mg/kg DDE) had been administered daily for 42 d since 6 wk of age and its effects had been observed until 12 wk of age. The administration of DDE did not produce any overt signs of toxicity. Neither physical development nor sexual maturation was affected, and serum biochemistry was not impaired at the dose used in this experiment. Moreover, the male reproductive organs and epididymal sperm count were not affected by the administration of DDE during the pubertal period. Our results showed that even immature male rats were resistant to DDE exposure at the daily dose of ca. 10 mg/kg, but metabolic and immunological changes still remained uncertain. Further investigation should be conducted to reveal all the effects of DDE on immature male rats.

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This paper presents the results of an investigation of respiratory symptoms, chest X-ray examinations, and analysis of antibodies to fungi of 138 fur-processing workers and 40 control workers. Industrial hygiene survey and environmental mycological studies were also conducted. The dust concentrations in fur processing workshops (1.8-6.7 mg/m ³) were below the national health limit (10 mg/m³). Most dusts in all fur processing workshops contained less than 2.0% silica. Numbers of isolated fungi in fur processing workshops [629-3,681 cfu/m³ (colony forming unit/m³)] were significantly higher than those in control environments (63-503 cfu/m³). The prevalences of respiratory symptoms in fur processing workers were higher than those in control workers, especially among female exposed workers. The prevalences of the symptoms in female exposed workers were 37.9% with chronic cough, 28.4% with chronic phlegm, 10.5% with dyspnea, 22.1% with chest tightness, and 4.2% with fever. Seven cases showed abnormalities in chest X-ray examinations. The OD_{450 nm} values for antibodies to fungi in fur processing workers were significantly higher than those in control workers (P<0.05). The prevalences of positive anti-fungi antibodies in fur-processing workers were also significantly higher than those in control workers (p<0.01). The results suggested that fungi might be one of the main allergens in respiratory diseases in fur processing workers.

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The aim of this study is to evaluate whether traffic policemen exposed to urban pollutants and possible psycho-social stressors could be at risk of changes on plasma adrenocorticotropic hormone [ACTH(P)] levels compared to a control group. Traffic policemen were matched by sex, age, length of service and drinking habit (<50 g of wine or beer per day) with a control group after excluding principal confounding factors; 62 traffic policemen with outdoor activity (34 men and 28 women) and 62 control subjects with indoor activity (34 men and 28 women) were included in the study. The levels of ACTH(P) were significantly higher in male and female traffic policemen than in the control subjects (respectively P=0.040, P=0.043). The authors hypothesise that occupational exposure to chemical and physical stressors, that may interact with possible psycho-social stressors, could cause a change in ACTH(P) levels in traffic policemen.

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