An in situ obtained graphite-fiber-based thin-film mercury microelectrode w
as used for determining lead(II) in natural water by stripping voltammetry
without removing oxygen and using no supporting electrolyte. Under the opti
mum voltammetric conditions (E-el = -1.2 V, t(el) = 5 min, c(Hg(II)) = 1 x
10(-7) M, Delta E = 40 mV, v = 105 mV/s), the calibration graph was linear
in the range of actual lead(II) concentrations in natural waters. At a lead
(II) concentration of 0.002 mg/L, the RSD was 11%.