[An epidemiologic study on vibration hazards among workers at the state forests in Kyushu (author's transl)]

There are only very few reports of epidemiologic analysis on vibration hazards among the workers at the state forests of Japan since 1970. It was necessary to perform investigations on the state of vibration hazards anew, through some labor hygienic policies on the prevention of the hazards, such as regulation of the time of using vibrating tools, had been executed to some extent since 1970. From the data of physical check-ups of 861 chain saw users of 24 District Forestry Offices in Kumamoto, Miyazaki and Kagoshima Prefectures in the south of Kyushu, the transition of vibration hazards was studied by using the incidence and prevalence of Raynaud's phenomenon and paresthesia of the fingers as indices. From the yearly transition of the hazards, a tendency was observed of increasing patients with vibration syndrome during the period from 1962 to 1970 when countermeasures on vibration hazards were not sufficient. However, since 1970 the occurrence of Raynaud's Phenomenon has shown a tendency to decrease among the workers with short history of using chain saw and the occurrence of paresthesia of the fingers as indices. From the yearly transition of the hazards, a tendency was observed of increasing patients with vibration syndrome during the period from 1962 to 1970 when countermeasures on vibration hazards were not sufficient. However, since 1970 the occurrence of Raynaud's Phenomenon has shown a tendency to decrease among the workers with short history of using chain saw and the occurrence of paresthesia of the fingers to increase among those with long history. The results are suggestive of making clear the pathophysiology of vibration hazards.