OCCUPATIONAL AND ACCIDENTAL EXPOSURE 



X-ray surveys or on X-ray work in Tuberculosis Bureaux, were examined 

 before commencing in their work and again after a period of four to seven 

 months. Two others who had worked in this type of activity for some con- 

 siderable time were examined during the period during which they were 

 engaged in this work and again after being for some months on work in which 

 there was no exposure to ionizing radiation. The changes in the latter two 

 cases were just the opposite to those found for the fourteen. The usual blood 

 tests were done by a technical assistant at the same time as the blood films 

 were taken for these newer tests. 



There were no significant changes in the counts of white cells, lymphocytes, 

 nor in the lymphocyte/neutrophil ratios. 



There appeared to be an increase in the eosinophil counts but this was not 



Change in absolute 

 lymphocyte counts 



Change in percentage 



of lymphocytes with 



granules 



Change in index 1 



Count 

 40001- 



3500 



3000 



2500 



2000 



1500 



1000 



500 



2270- 



Change fall of 5% 



Index 1 



AO 



35 



30 



25 



24 66-^ 



20 



15 

 —2649 



10 



*-7-43 



Change fall of 69 9% 



Before 

 exposure 



After some 

 months 



Before 

 exposure 



After some 

 months 



Before 

 exposure 



After some 

 months 



Figure 6. Results of tests on occupationally exposed persons 



Statistically significant. However, if the differences between the two values 

 for each person were expressed as a percentage of the first pre-exposure 

 value, the mean of such percentage difierences was significant, P<0-001. 



The values are shown in Figures 5, 6 and 7. The lines joining the points 

 are meant merely to indicate the corresponding points for each different 

 individual. The results of statistical analysis of the values are as shown in 

 Table 5. 



The results shown above indicate the value of paying attention to structural 

 characteristics rather than to mere numbers. For instance, although the 

 absolute lymphocyte counts remained significantly unaltered after some 

 months' exposure, the absolute count oi small lymphocytes showed a marked 



44 



