Erratum: "Heavy metals"-A meaningless term? (IUPAC Technical Report) (Pure and Applied Chemistry (2002) 74 (793–807) (2002) DOI: 10.1351/pac200274050793)

Abstract

Another group of definitions is based on atomic number. Here there is more internal consistency since three of the definitions cite "heavy metals" as having atomic numbers above 20, that of calcium. Interestingly, one of them comes from the chapter by Lyman in Rand (1995) [21] and contradicts the definition favoured by Rand himself cited in the previous paragraph. The problem with citing metals of atomic number greater than calcium as being "heavy" is that it includes essential metals such as iron and zinc and flatly opposes the historic basis of definition based on density, since it includes elements of density lower than any that has been used as a defining property by other authors. Burrell s definition [22] even includes the semimetals, arsenic and tellurium and the nonmetal selenium.