The summary of physical examinations made at beginning of study shows four males and five females. No serious defects were found in any of the group. Two of the males had symptoms of the skin of the fingers and hands which are suggestive of the effects of radiation. One male attributes his nervousness and digestive disturbances to continued exposure to radiation. He states that members of his family, without actually knowing whether he had been exposed to radiation or not, could accurately tell by his increased nervousness and irritability that he had been exposed to radiation. Two females had enlarged thyroid glands. The cardiac findings in all the females are thought to be functional. Menstruation in the females had not been disturbed by exposure to radiation. One female (No. 5) had recently returned from two months' sick leave. A physician had made a clinical diagnosis of anemia and nerve fatigue. At the time of the physical examination made during this study, she still felt nervous and depressed. It will be noted that in all the cases except in No. 4, No. 5, and No. 8 there seems to be a rather low blood pressure. Case No. 5 had only recently returned from sick leave when this reading was made. Case No. 8 works with radium only one day a week, thus leaving case No. 4 as the only one whose blood pressure apparently was not lower than it normally should be. These blood pressure readings were made with a Tycos instrument, the auscultatory method being used.

The physical examinations, therefore, seem to show that, of the nine persons examined, only two presented any signs of the effect of radiation upon the skin, and that exposure to radiation apparently produced a lowering of blood pressure in the majority of cases. It was thought that there might exist a relation between the decrease of red or white blood cells in certain members of the group and the low blood pressure, but it appears, upon careful study, that such was not the case. (See Table III.)

The next step in the investigation was an examination of the blood to determine whether any changes could be noted. An examination of the blood of the employees of the section made on February 6, 1922, gave the results shown in Table II.

TABLE II.-Summary of initial blood counts made February 6, 1922.

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In the studies made by Mottram, anything less than an 8 per cent variation was considered "no change." Applying this standard to the blood examinations tabulated above, we find that all in the group were below normal in polymorphonuclear neutrophiles. Two (No. 3 and No. 5) were below normal in small lymphocytes. All save one (No. 8) were above normal in large lymphocytes. Three persons (No. 4, No. 6, and No. 8) were below normal in total white cells. Two persons (No. 5 and No. 6) were below normal for total red cells. Thus we find that three persons (No. 5, No. 6, and No. 8) had a deviation from normal in more than one of the cellular constituents of the blood.

Following the initial examination and blood counts, other blood counts and blood-pressure readings were made at intervals varying from two weeks to two months, covering a period of about a year and a half. The accompanying graphs show results of these several blood counts.

It will be noted that cases No. 10, No. 11, and No. 12 appear in the graphs. These represent employees who entered the section after the study had begun. A record of their physical examinations will be found in the summary shown in Table I, except No. 10, upon whom no physical examination was obtained before he left the section. Again applying the standard that anything less than 8 per cent variation is considered "no change," we find that there were changes and variations in the blood picture as follows:

For the polynuclear neutrophiles there was a tendency to be somewhat below normal, although the last count shows all save one within allowable limits. All members of the section show a decrease below normal in the number of small lymphocytes. The large lymphocytes vary and most of the time are above normal, but the last two counts show a decline in all the members of the section. The total white cells vary also; the last count shows four persons below normal limits, two dropping to 4,900. The last count of total reds shows three below the allowable limit; and during the year several other individuals fell below the lower limit. In the studies to be made henceforth it is planned to run a control group for blood counts. It appears probable that there are appreciable individual differences in the resistance to changes in the blood.

Table III, showing blood-pressure records, is of interest. The readings were made by the auscultatory method; a Tycos instrument was used most of the time. On one or two occasions a mercury instrument was used. From this table it is evident that most of the workers in the radium section have a rather low blood pressure, both systolic and diastolic, as compared with the commonly accepted normal, and that these low blood pressures have continued persistently during the entire period of this study.