A study was undertaken to investigate the magnitude of potential trace metal contamination contributed by various commercial evacuated blood tubes to blood samples under experimental conditions. None of the tubes tested contributed significant Cu contamination whereas the 1% nitric acid and human blood leaching data clearly indicate that Zn, Pb and Cd contamination of blood samples can be a significant problem with certain blood collection tubes under normal handling, shipping and storage conditions. The implications of these experimental findings are discussed. It is recommended that several of the evacuated blood tubes be leach tested prior to use with blood or plasma and the eluate analyzed for potential trace metal contamination problems.