Table 2

Exposure estimates by case status for Y-12 participants

Exposure metricControlBeSCBDBeS/CBD
All participants, n127351954
 Year of first beryllium exposure1970 (1970)1973 (1970)1973 (1969)1973 (1970)
 Years with direct beryllium exposure*3.2 (1.3)2.1 (0.48)3.7 (2.3)§2.6 (1.4)
 Assigned cumulative exposure, μg/m3-years3.91 (0.98)3.44 (0.26)8.79 (2.64) §5.33 (0.89)
 Assigned lifetime-weighted average exposure, μg/m30.13 (0.03)0.12 (0.02)0.32 (0.11) §0.19 (0.04)
 Highest task exposure, μg/m31.81 (1.00)1.16 (0.26)3.75 (1.19) §2.07 (0.63)
Participants never working at K-25, n80141024
 Year of first beryllium exposure1971 (1969)1970 (1970)1970 (1970)1970 (1970)
 Years with direct beryllium exposure*3.5 (1.2)3.8 (2.4)5.7 (4.2)4.6 (3.4)
 Assigned cumulative exposure, μg/m3-years5.24 (1.02)3.88 (2.43)15.31 (3.86)8.64 (3.08)
 Assigned lifetime-weighted average exposure, μg/m30.17 (0.03)0.15 (0.10)0.54 (0.13)0.31 (0.12)
 Highest task exposure, μg/m32.05 (1.00)1.08 (0.38)3.27 (1.78)1.99 (1.00)
  • Values are mean (median).

  • * Years×% time.

  • Maximum assigned beryllium exposure for any work task regardless of length of exposure.

  • p<0.05 versus controls (Wilcoxon rank sum).

  • § p<0.05 versus BeS (Wilcoxon rank sum).

  • 0.05<p<0.10 versus controls (Wilcoxon rank sum).

  • BeS, beryllium sensitisation; CBD, chronic beryllium disease.