Table 1

Comparison between active and retired miners in 1994 (n=171)

Active miners (n=131) Retired miners (n=40) p Value
Age (y, mean (SD))45.6 (3.2)49.7 (2.0)0.0001
Estimated cumulative exposure to dust (mg/m3.y, mean (SD))51.2 (41.4)67.2 (44.2)0.04
Smoking (%):
 Current smokers5530
Selenium concentration (ng/ml, mean (SD))63.6 (19.1)67.9 (15.9)0.2
Plasma GSH-Px (U/l, mean (SD))694 (234)748 (227)0.2
Erythrocyte GSH-Px (U/g Hb, mean (SD))38.8 (12.5)44.6 (13.7)0.01
Adjusted means:
 Age and smoking adjusted Se concentration (ng/ml)62.672.20.01
 Age and smoking adjusted plasma GSH-Px (U/l)6807850.04
 Age and smoking adjusted erythrocyte GSH-Px (U/g Hb)38.546.50.003