[Studies on health hazards among cooks providing school lunch service. Report 2. An analysis of factors associated with the development of health hazards].

The previous report revealed that the musculoskeletal symptoms of cooks are related to their working conditions, but the cause and effect relationship was not clarified. In the present report, the relationship between some causative factors and the health hazards is analyzed epidemiologically. The subjects were chosen from the cooks mentioned in the previous report. The results are as follows: A clear relationship was not observed between age and health hazards. A dose-response relationship was observed between the cumulative duration of cooking work and the subjective symptoms. An antecedent-consequent relationship was also shown between the cooking work and the health hazards. Another dose-response relationship was observed between the amount of cooking work and the subjective symptoms. The frequency of "carrying heavy objects" assigned as a cause of development of the hazards, especially of low-back pain, increased in accordance with the number of meals served in each kitchen. It was observed that the improvement of cooking equipment enabled the incidence of symptoms to decline, but the elevation of working speed due to mechanization could still be hazardous. As a result of the physical examination, a similarity was observed between the cooking work and the clinical findings in comparison with ticket-vending machine operators. It is concluded that these results demonstrate a cause and effect relationship between cooking work and the development of health hazards.