[Significance of measuring urinary 17-ketosteroid sulfates at the work-place].

We examined availability of urinary 17-KS-S to evaluate work and job strain by presented the results in two field research and one experiment. It became clear that urinary S/OH was a comprehensive parameter of thermal strain, under the combined load condition of temperature and exercise, and as an additional factor, under the various load conditions of air velocity. Significant changes of urinary S/OH before and after the rest break and holiday suggested that the findings reflected fatigue conditions. This suggestion was strongly supported by the finding that the values of urinary S/OH on the first day-off after a mid-night shift and those 1 to 3 days later were not able to recover to the value before the night shift. A ratio between urinary 17-KS-S and 17-OHCS, S/OH, suggests a method of evaluating the degree of strain and the condition of fatigue and over-fatigue by measuring these parameters and thus clarifying the work conditions and work-place environment.