Have you ever wondered which elements of the periodic table are toxic? Or maybe why they're toxic? The truth is everything is toxic if the dose is high enough—even water. (We're talking a lot of water, though.) There are some elements that are, of course, more toxic than others and should be avoided at all costs.
Most toxic elements like mercury and lead are deadly because they accumulate in the body over time, and unless action is taken, they stay there until death occurs. This means that there is no safe exposure limit for certain elements.
What about exposure to a small amount of mercury throughout life? No big deal. Don't freak out if you break a thermometer. However, exposure to mercury many times can cause a buildup of the element in the body. Too much mercury and you are a goner.
Ever wondered where the term "mad as a hatter" comes from? Or after watching Alice in Wonderland did you wonder why Johnny Depps' character was so zany? It's all because of the mercury. Way back in the 1800's hat makers (or hatters) used mercury when processing pelt for hats.18 These poor workers were exposed to a lot of mercury. The element attacks the nervous system (the brain) so exposure to a lot of it makes a person seem like they've gone mad.
What does mercury actually do damage to the body? It binds to –SH groups, which are found in many tissue enzymes and proteins.18 When it is bound to the –SH groups it acts like a Trojan Horse and enters the cells. Once mercury has made its way into biological cells, havoc breaks loose…organ failure and eventually death.
There are other elements, like polonium, that can cause immediate death upon exposure. Most of these elements are radioactive. The amount of polonium required to cause death is almost unbelievable. Just seven picograms of polonium can generate enough radiation to kill a human. That amount of polonium is equivalent to a speck of dust!
Polonium can enter the body by eating or drinking contaminated goods, breathing contaminated air, or by exchanging bodily fluids with a contaminated person. Once in the body the element decays and releases an alpha particle, which consists of two protons and two neutrons with a positive +2 charge.19 These particles are extremely high in energy and cause massive amounts of internal damage. Imagine shrinking a million crazy Sonic the Hedge Hogs and letting them loose in your body. The results are not pretty.
It has been said that radiation poisoning from polonium looks like the end stage of cancer.19 The kidney and the liver break down and the poor contaminated person often experiences vomiting, diarrhea, and hair loss. Unfortunately there is no cure for this type of ailment.
The important thing to remember is that all elements are safe if proper safety, handling, and protocols are used.