Environmental Pollution and Heavy Metals

We have already seen in earlier chapters that even essential metal ions can be toxic — as the historical father of toxicology, Paracelsus (1493—1541), wrote 

In what follows, we pass in review aluminium, cadmium, mercury, lead, and chromium toxicity before turning briefly to metals as poisons. 

Perhaps Humpty Dumpty s definition in Alice through the looking glass by Lewis Carrol fits the bill When I use a word, it means just what I choose it to mean — neither more nor less . 

Biological Inorganic Chemistry, 2nd Edition. DOI 10.1016/B978-0-444-53782-9.00023-1. Copyright 2011 Elsevier Inc.. All rights reserved. 

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