Electrothermal vaporization (ETV) as a means of sample introduction for inductively coupled plasma mass spectrometry (ICP-MS) has been applied to the study of fundamental processes occurring within the graphite vaporization tube. The application of ETV-ICP-MS to the analysis of real samples requires the careful selection of experimental conditions as well as the use of a chemical modifier. Chemical modifiers can act as physical carriers improving the mass transport efficiency of analyte from the ETV to the argon plasma resulting in better sensitivity and linear calibration curves. For the analysis of materials such as Arctic snow and slurries, ETV-ICP-MS was found to be from 2 to 350 times more sensitive than graphite furnace AAS for the determination of tranition elements and from 10⁴ to 10⁶ times more sensitive for the determination of the rare earth elements. ETV-ICP-MS was successfully applied to the determination of Cd isotope ratios in ruminant blood and tissue samples.