There were performed biochemical and cytological studies of blood in healthy workers of chrysotile asbestos plant in order to determine the functional state of the body, depending on the length of service and working conditions. Mentioned differences between the functional state of the organism were determined in the longitudinal study, under construction on schedule time series with the test group at specified intervals (every year for 7 years surveyed, the same group of healthy workers). The differences between the indices allow one to discriminate different levels of the functional state of the organism for the workers employed at processing complex with experience of 4 and 5 years, and for the employees in the mining and transport workshop with the experience of 5 and 6 years. As a result the work experience of 5 years is considered to be an occupational hazard for workers at processing complex, and 6 years of experience - as an occupational hazard for workers of mining and transport workshop.