Appendix B

Subcohort for Dose-Response Analysis

The subcohort for dose-response analysis includes all white males from the study cohort who worked at ORNL or Y-12 for at least part of their employment in Oak Ridge nuclear facilities. For the dose-response analyses follow-up began 365 days after first hire at either ORNL or Y-12. Table B1 summarizes the number of individuals, deaths, and person-years lost by imposing a 365 day entry criterion on the cohort for the facility comparison analysis. The remaining tables in this section provide information on the demographic and exposure data of this subcohort. Additional figures are also supplied to provide exposure data information by year and facility.

Table B1
Impact of 365 Day Entry to Follow-Up
  Total Number Total Deaths Total Cancer Deaths Total Person-Years
Entering Follow-Up 30 days after hire by either ORNL or Y-12 28,770 4,821 1,138 629,636
Entering Follow-Up 365 days after hire by either ORNL or Y-12 28,347 4,786 1,134 603,500

 

Table B2
Distribution of Covariables
  (28,347)
White Males
Birth cohort

before 1/1/1900

729 (2.6)

1/1/1900 - 12/31/1909

2,190 (7.7)

1/1/1910 - 12/31/1919

5,059 (17.8)

1/1/1920 - 12/31/1929

7,221 (25.5)

1/1/1930 +

13,148 (46.4)
Length of Employment

< 1 year

5,064 (17.9)

1 year +

23,283 (82.1)
Paycode

Nonmonthly

20,538 (72.3)

Monthly

7,809 (27.7)

 

Table B3
Average Years of Employment and Follow-Up
  White Males
(28,347)
Years of Employment
Mean 11.6
Median 7.5
Years of Follow-Up
Mean 21.3
Median 22.4

 

Table B4
Distribution by Facility
Facility (28,347)
Number of Workers (%)
ORNL only 11,127 (39.3%)
Y-12 only 8,525 (30.1%)
Multiple facilities* 8,695 (30.6%)

Total

28,347

*At least one of these facilities must by ORNL or Y-12.

 

Table B5
Distribution of Unadjusted External Doses with Lags
  Recorded Dose Lag 2 Lag 10 Lag 20
Total external dose (cSv) 36,720 35,970 31,870 20,800
% of total recorded dose for entire study cohort (90.6) (88.7) (78.6) (51.3)
Number of workers by cumulative external dose (%)

<1 cSv

21,561 (76.1) 21,739 (76.7) 22,550 (79.5) 24,397 (86.1)

>/= 1 to < 5 cSv

5,438 (19.1) 5,278 (18.6) 4,598 (16.3) 3,156 (11.1)

>/= 5 cSv

1,348 (4.8) 1,330 (4.7) 1,199 (4.2) 794 (2.8)

mean cumulative dose (cSv)

1.30 1.27 1.12 0.73

median cumulative dose (cSv)

0.21 0.19 0.09 0
Quantiles (cSv)

100%

461.87 461.87 461.74 461.20

75%

0.95 0.92 0.77 0.32

25%

0 0 0 0

0%

0 0 0 0

 

Table B6
Distribution of Annual Internal Exposure Values
ORNL (1945-1984) Y-12 (1947-1984)

not monitored

116,595 (79.9) 125,914 (72.9)

monitored but not exposed (%)

9,434 (6.4) 7,216 (4.2)

monitored and exposed (%)

19,979 (13.7) 39,600 (22.9)

Total

146,008 172,730

not eligible for monitoring* (%)

13,439 (9.2) 7,060 (4.1)

eligible but not monitored (%)

103,156 (70.7) 118,854 (68.8)

monitored (%)

29,413 (20.1) 46,816 (27.1)

Total

146,008 172,730

*Any year of employment before 1951 is considered to be not eligible for internal monitoring.

 

Figure B1: Percent of ORNL Workers Monitored

FIG0B1.GIF (33239 bytes)

 

 

Figure B2: Percent of Y-12 Workers Monitored

FIG0B2.GIF (72437 bytes)


Figure B3: Percent of ORNL Workers by Annual Internal Exposure Indicator

FIG0B3.GIF (9479 bytes)

 


Figure B4: Percent of Y-12 Workers by Annual Internal Exposure Indicator


FIG0B4.GIF (14538 bytes)


Figure B5: Percent of K-25 Workers by Annual Internal Exposure Indicator
FIG0B5.GIF (30031 bytes)

Table of Contents