A field survey of 278 engineers (20-59 years) in a machinery manufacturing company was conducted to investigate the association of working hours with biological indices related to the cardiovascular system (heart rate variability, blood pressure and serum levels of magnesium, dehydroepiandrosterone sulfate and cholesterol). Average working hours (defined as <"hours at workplace" + "half a commuting time">) and sleeping hours in this study were 60.2 +/- 6.3 hr/week and 6.6 +/- 0.8 hr/day respectively. There were no significant relationships between working hours and biological indices related to the cardiovascular system, but sleeping hours was closely related to working hours negatively. Furthermore, the serum DHEA-S level was significantly related to sleeping hours positively. Combining these two results, it appeared that long working hours might lower the serum DHEA-S level due to the reduction of sleeping hours.
Objectives : To obtain reference values for the pulmonary asbestos and non-asbestos fiber contents of residents in Korea and to compare them with similar results from Japan. Methods : The autopsied lung specimens from 22 deceased people (20 males and 2 females) in Pohang, without any known occupational history of asbestos exposure, were analyzed for incidence of asbestos and non-asbestos fibers by transmission electron microscopy with energy dispersive X-ray analysis after using low temperature ashing procedures. Results : Chrysotite fiber (46.2%) was the major fiber type found in the lungs of the subjects. The asbestos fiber concentrations found in males and females were fiberss(g of dry lungs) and fibers/(g of dry lungs), respectively, showing a geometric mean concentration fibers/(g of dry lung tissue), due to the predominance of males in the sample. The non-asbestos fiber contents in males and females were fibers/(g of dry lungs) and fibers/(g of dry lungs), respectively, with a geometric mean concentration fibers/(g of dry lung tissue). Conclusions : Residents in Pohang had significantly lower levels of both asbestos and non-asbestos fibers than urban residents in Korea. Furthermore, Koreans had significantly lower levels of both asbestos and non-asbestos fibers than Japanese.
Changes in Cholinesterase Activity, Nerve Conduction Velocity, and Clinical Signs and Symptoms in Termite Control Operators Exposed to Chlorpyrifos: Masahiro Gotoh, etal. Asahi Rosai Hospital— We have surveyed periodical medical examinations for pest and termite control operators (n=64) exposed to chlorpyrifos and other organophosphate pesticides. Distribution of serum butyrylcholinesterase (BuChE) activities of all workers ranged 0.01‐1.18 (ApH). Serum BuChE activities in 6 workers in one termite control company were severely depressed and ranged from 0.01 to 0.21 ΔpH. Erythrocyte acetylcholinesterase (AChE) activities in 3 workers were lower than the normal range. Erythrocyte AChE activities and serum BuChE acitivities in chlorpyrifos sprayers were significantly correlated (r=0.720). In other clinical signs, blood urine nitrogen (BUN) in 4 workers and white blood cell (WBC) counts in 4 workers were abnormal. Sensory nerve conduction velocities in the sural nerve of all 6 workers were significantly reduced to 18.8‐26.6 m/s in the left leg and 19.2‐27.2 m/s in the right leg. In the results of ophthalmic examinations, accommodation time (both eyes) in 4 workers extended over the normal range and electroretinography (ERG) in 2 workers showed abnormal ERG including disappearance of oscillatory potential. Chlorpyrifos residue in blood in 4 operators whose serum BuChE activities ranged from 0.01 to 0.03 ApH were detected in the range 2‐8 ng/m 1. They had sprayed chlorpyrifos daily for 5 d before every blood sampling. It is suggested that serum BuChE activity and sensory nerve conduction velocity are sensitive indicators to evaluate the effects of chlorpyrifos exposure, and may be used effectively to monitor exposure and the effects of chlorpyrifos on health.
We investigated the relationship between musculoskeletal disorders and sleep problems among 98 employees (79 women) at three nursing homes. Self-reported data were collected regarding pain in the neck, shoulders, arms, legs, and low back, sleep disturbances, daytime sleepiness (Epworth Sleepiness Scale), and the level of workload on the hands, legs, and low back by type of care. Pain in the arms was significantly associated with less difficulty initiating sleep, fewer symptoms of insomnia, and a higher level of daytime sleepiness. After adjusting for age and gender, only the association between arm pain and daytime sleepiness remained significant (Odds Ratio 6.70, 95% Confidence Interval 1.40-31.97). Participants with both arm pain and daytime sleepiness showed significantly greater levels of workload in some kinds of care in a systemic manner than counterparts without either complaint. These findings suggest that arm pain is associated with elevated sleep propensity/fatigue in nursing home work.
A field survey of 147 engineers (23-49 years) in an electronics manufacturing company was conducted to investigate the effect of working hours on cardiovascular-autonomic nervous functions (urinary catecholamines, heart rate variability and blood pressure). The subjects were divided into 3 groups by age: 23-29 (n = 49), 30-39 (n = 74) and 40-49 (n = 24) year groups. Subjects in each age group were further divided into shorter (SWH) and longer (LWH) working hour subgroups according to the median of weekly working hours. In the 30-39 year group, urinary noradrenaline in the afternoon for LWH was significantly lower than that for SWH and a similar tendency was found in the LF/HF ratio of heart rate variability at rest. Because these two autonomic nervous indices are related to sympathetic nervous activity, the findings suggested that sympathetic nervous activity for LWH was lower than that for SWH in the 30-39 year group. Furthermore, there were significant relationships both between long working hours and short sleeping hours, and between short sleeping hours and high complaint rates of "drowsiness and dullness" in the morning in this age group. Summarizing these results, it appeared that long working hours might lower sympathetic nervous activity due to chronic sleep deprivation.
We examined the relationship between muscle injection of drugs into the quadriceps and its contracture.Subjects were children who had received medication at a clinic during the period from January 1967 to December 1970. Among the patients of the clinic, a high incidence of quadriceps contracture had been observed during the period.As basic data, we took the results of interviews with the subjects, the results of clinical examinations for quadriceps contracture, and medical records of the subjects which had been kept in the clinic.The following results were obtained.1) There were no abnormalities among the subjects who had never been injected in the quadriceps muscle. The incidence and the severity of quadriceps contracture were closely related to the total amount of the drugs injected into the muscles.2) The total numbers of injections of the following drugs were significantly larger in subjects with symptoms of contracture than in subjects without any symptoms.The drugs were Terramycin (Ox-tetracycline), Obelon (Sulpyrin, Aminopropyrin, Theoclate diphenyl pyralin), Chloromycetinsol (Chloramphenicol), Atarax-P (Hydroxyzin hydrochloride), Gammavenin (immuno-Globlin), Panvitan (Vitamin A-D), 10%-Pantocin (Pantethine) and Phenobarbital (Phenobarbital natrium).3) It was revealed by means of quantification theory type II analysis that the main attributable factors of muscle contracture might be the age when the subjects had been injected for the first time, the total number of Terramycin+Obelon injections, and the experience of injection of 10% Pantocin or Phenobarbital, but sex and the year of the beginning of injection might be ignored.Discrimination based on these results between the two groups, a normal group and a moderate or more severe symptomatic group showed reasonable sensitivity and specificity.
'%3e%3ccircle r='20' fill='%23008'/%3e%3ccircle r='17.5' fill='%23fff'/%3e%3ccircle r='3.5' fill='%23008'/%3e%3cg id='d'%3e%3cg id='c'%3e%3cg id='b'%3e%3cg id='a' fill='%23008'%3e%3ccircle r='.875' transform='rotate(7.5 -8.75 133.5)'/%3e%3cpath d='M0 17.5.6 7 0 2l-.6 5L0 17.5z'/%3e%3c/g%3e%3cuse xlink:href='%23a' transform='rotate(15)'/%3e%3c/g%3e%3cuse xlink:href='%23b' transform='rotate(30)'/%3e%3c/g%3e%3cuse xlink:href='%23c' transform='rotate(60)'/%3e%3c/g%3e%3cuse xlink:href='%23d' transform='rotate(120)'/%3e%3cuse xlink:href='%23d' transform='rotate(-120)'/%3e%3c/g%3e%3c/svg%3e)
