This periodic table summarises daily upper intake limits for various elements (data taken from a variety of sources). Of the elements highlighted, Thallium is the most toxic. However, some of these elements, like copper, are essential minerals for which there is also a recommended daily intake. Remember, the dose makes the poison.
Periodic table produced using R. Click to zoom.
Important note: these limits are for the most common form of elemental intake, e.g. sodium salts, phosphates, chlorides. One would not want to ingest Na, P, or Cl in elemental form!
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