The determination of trace metals in sweat by anodic stripping voltammetry.
Sweating was induced on the forearm of subjects by pilocarpine iontophoresis, and the sweat collected on a small membrane filter. Zinc, cadmium, lead and copper were then determined in the filter by anodic stripping voltammetry (ASV) using one of two alternative techniques: leaching the filter with a supporting electrolyte (0.1 M NaNO3/0.002 M HNO3), followed by ASV of the leachate; or, direct ASV analysis of the trace metals in the membrane filter using a novel thin-layer cell. Average values found for zinc, cadmium, lead and copper in sweat from males were (micrograms 1-1): 720, less than 3, 15 and 80, respectively. Copper in sweat from females was lower (23 micrograms l-1) than for males, although use of oral contraceptives appeared to increase copper concentration.