Concentrations of Ti (from the titanium electrodes), Fe (from the stainless steel electrodes), Pt (from the platinized-titanium electrodes), and elemental carbon (from the graphite electrodes) migrating into the heating media were taken as measures of electrode corrosion. In each experimental run, once the ohmic heating was completed, a 25.00 (±0.03) ml sample was pipetted out, after removing the electrodes and thoroughly mixing the fluid. A 25.00 (±0.03) ml sample of the respective unheated heating medium was used as a method blank. All the samples were collected into polypropylene sample bottles, and then stabilized by adding concentrated nitric acid (5%, v/v). Quantitative analyses of the metal ions were performed by a Perkin–Elmer Sciex ELAN 6100 DRC inductively coupled plasma–mass spectrometer (ICP–MS) [12]. The elemental carbon concentrations were determined by a Perkin–Elmer Optima 3000 DV inductively coupled plasma–optical emission spectrometer (ICP–OES) monitoring the emission spectra near 193.03 nm.