1. A critical appraisal of periodic physical examinations in occupational health practice is attempted discussing some specific aspects of the industrial health maintenance program in Japan. The periodic physical examination of the country have mainly been done to detect a limited number of patients of chronic non-occupational illness. This is because the detection and control of tuberculous patients have long been the major concern of the industrial health service. Experiences since pre-war days of periodic examinations providing tests of detecting tuberculosis may have resulted in application of periodic examinations pertaining almost exclusively to chronic adult diseases which are detectable in terms of diagnostic screening tests.
2. Legal provisions on periodic health checks back to 1929. The original provisions paid special attention to the relevance to workers' health of various occupational hazards and stresses, but they were realized only incompletely in the industrial practice. In contrast to widely distributed periodic examinations for the control of tuberculosis and some other non-occupational chronic diseases, the impact of environmental factors, especially those born of the recent technological innovation, upon workers have been made light of special tests provided periodically for workers exposed to specific toxic agents, on the other hand, have usually no essential relation to the periodic health appraisal mandatory for all employees. Some social backgrounds promoting such a tendency should be taken into account.
3. It should be noted that the periodic physical examination is in general the major and often the only activity of health service within enterprises. The part of an industrial physician or a health service staff, however, must be combined with competence in utilization of individual and collective data that pertain to the qualities of the occupational environment as a whole. The tendency to evaluate environmental effects only through detection of chronic illness which are definable by limited and specialized testings may have resulted also from the past policies of occupational health administration. In not a few cases, the periodic application of formulated physical examinations goes ahead of a fair grasp of occupational health risks existing in workplaces, so that the absence of abnormal test results is very often considered as an evidence of acceptable working conditions.
4. Reassessment of the multi-item mass screening system in periodic health appraisal, planning of a more efficient health examination system, including reduction of roentgenological exposure, and re-education of industrial physicians and other health service personnel are urgent problems. In brief, the periodic physical examination system for industrial workers is at an important turning-point.

抄録全体を表示

Fifty-five female rats were divided into 7 groups and 6 groups of them were given cadmium. by different routes. Cadmium was given to the rats by subcutaneous injections (repeated injections of 120 μg Cd/rat) or by supplementary diets (20 ppm or 2 ppm Cd in diet). Urine samples were collected three times during 35 experimental weeks and were analysed for cadmium, protein and glucose.
Results obtained are as follows :
1) Repeated injections of cadmium brought about increased excretion of cadmium in the urine, and the injected amount of cadmium was linearly related roughly to the excreted amount of cadmium up to 36 injections independent of the difference of the injection interval and of the time of injection. But after 36 injections suddenly a remarkable increase of cadmium excretion was observed.
2) The rats fed with 20 ppm Cd diet over a period of 17 weeks showed only a slight increase of cadmium excretion in the urine, while the rats fed with 2 or 20 ppm Cd diet for 9 weeks after 27 injections of cadmium excreted a remarkable amount of cadmium in the urine. The excreted amount of protein and that of cadmium in the urine were correlated each other in these rats. This suggests that the renal damage would have been caused in these rats.

抄録全体を表示

Statistical analysis of skin temperatures in male office workers was made in connection with the seasonal difference between summer and winter on various spots of the body. According to the Research Committee on physiological reaction to climatic seasonal change in Japan, seasonal : variation of the skin temperature was observed obviously throughout the year. Skin temperatures of extremities varied greater than those of many other selected areas of the body to the change of thermal environment. These previous results, however, had been obtained under seasonal change uncontrolled to some large. extent. In our study, mean air temperature of the room, in which measurement was done, was maintained at 24.6°C in summer and 23.5°C in winter by the central system of air conditioning. Therefore, the purpose of our study was to investigate the seasonal difference of the skin temperature among workers under a modern working conditions that the thermal difference in both seasons was eliminated. The change of skin temperatures were estimated by the use of a bioelectric thermographic computor at three spots including forehead, finger and toe. The results obtained were as follows :
1) As shown in Table 1, the standard deviation of the forehead skin temperature ranged from 0 to 1.04°C as to variance components. They were divided into three parts (a) within person (b) between persons (c) between seasons. The range of the forehead skin temperature showed that it varied with thermal environment to a relatively small extent in comparison with the skin temperature of extremities.
2) The finger skin temperature varied markedly with the individuality of physiological responces, while the toe skin temperature had a remarkable difference between summer and winter.
3) As shown in Table 2, correlation between the room temperature and each skin temperature was significant in summer. On the contrary, there was no significant correlation in winter.
4) Table 3 shows that the forehead skin temperature was much higher than that of two others. In addition to that, it was noted that the forehead skin temperature in summer was lower than that in winter. On the other hand, the toe skin temperature was lower than that of the finger skin temperature in without regard to the season.

抄録全体を表示

溶接作業時に金属fumeを吸入することにより, いわゆる金属熱を起こすことが知られているが, この原因物質および発症のmechanismに関して諸説があるが確定的なものは未だない.われわれは溶接棒の有害性の検定法を確立する目的で, そのfumeの適用量を適確にするため, 吸入法のほかに注射法について試みた結果, 静脈内投与によっても家兎は発熱し, 発熱経過は原因金属の体内分布の時間的変動とよく一致した.すなわち, 金属熱の発症には必ずしも気道粘膜の損傷が必須でなく, むしろ直接作用であるかの示唆が得られた.また用量-反応の関係の存在も認めた.さらに溶接fumeの発熱patternは, LPSやZnO fumeとは, 時間的変動, 耐性獲得の有無等でも異なることを認めた.近年開発された低水素型溶接棒がとくに毒性が高いといわれているが, われわれの実験では, 溶接棒種による差はとくに明確な差が認められなかった.

抄録全体を表示

溶接fumeの有害性については, すでに多くの報告があり, そのほとんどは溶接粉塵の長期間吸入による溶接工肺に関するものである.著者らは溶接作業時に吸入されたfume中の金属化合物がいかなる時間的経過をもって排泄されるかを知る目的で, 動物に実験的に溶接fumeを吸入または注射し2, 3の金属元素について観察した.Fume中に存在する金属酸化物は10数種あり, これらを構成する金属のうちでも生理的に存在の認められている元素と, そうでない元素とでは, その吸収, 排泄の様態も異なると思われる.したがって今回はまず生体内にも存在するFe, Mn, Mgを指標として, 原子吸光法により測定.その結果, 1回のみの暴露によっても排泄にかなりの時間を要し, 長時間かつ連日暴露される条件のもとでは, 慢性的に蓄積の起こることが考えられ, 溶接工肺に見られるような肺における有害性にとどまらず, 中枢その他への慢性的影響の可能性も考慮に入れられねばならないことを知った.

抄録全体を表示