Small effect on plasma selenium level by occupational lead exposure.

Selenium level in plasma (P-Se) was slightly, but statistically significantly (2p = 0.02) lower in 25 lead-exposed secondary smelter workers (P-Se 1.09 +/- 0.02 mumol l-1, mean +/- SEM; blood lead level, B-Pb, 1.9 +/- 0.1 mumol l-1) than in 25 matched controls (P-Se 1.16 +/- 0.03 mumol l-1; B-Pb 0.2 +/- 0.01 mumol l-1). Further, there was a significant negative (2p = 0.02) correlation (r = -0.33) between B-Pb and P-Se. The data indicate a minor interaction, in humans, between occupational lead exposure and selenium status.