Currently, the analysis of metals for toxicity evaluation are only assayed for total quantity/quantitative elemental analysis, and no assessment to date evaluates the individual toxicities and sum total toxicities of the individual chemical forms of metals, which can be radically different. A better assessment of true toxicity can be made by looking at the quantitative numbers of each of the chemical forms the metal exists in as a function of one of the different valuations of toxicity, such as LD50 numbers, LD0, LD100, LC50, LOAEL, NOAEL, PEL, REL, TLV, etc., for a new terminology of Toxic Relevance Number (TRN), and the sum of TRN's for the individual chemical forms as TTRN, Total Toxic Relevance Number. While LD 50 is preferred, any of these valuations can be used in the same model to advance our understanding and assessment of true toxicity of a certain metal in a specific exposure.
