Lurking inside your faucet is
a chemical that seems safe,
but can actually be a deadly poison – water.
So now you’re probably wondering
what the heck ISN’T toxic if a thing
that you drink every day can kill you,
but if you don’t drink it,
that’ll kill you too.
We spoke to poison expert Debrorah Blum,
and we learned some pretty darn
interesting facts about the diverse
array of poisons out there.
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“I think of poisons as really cleverly evil compounds,
because most chemical compounds,
including the ones that build our bodies
sustain us in one way or another,
and a poisonous compound is a chemical
compound that knows how to turn
a lock your body and do harm.”
Before we get into specifics,
it’s good to know exactly how
we qualify something as poisonous.
Back in the Renaissance,
the grandfather of toxicology, Paracelsus,
gave us a saying that sums it up,
“The dose makes the poison.”
“So he made a point about poisons,
which was that everything is poisonous
or not depending on the dose.
If you take a compound like arsenic,
in a very tiny dose, it doesn’t kill you.
In a very large dose it does.
Now, from the 21st century perspective,
Paracelsus was right and wrong. Yes,
everything notches up according to dose,
but there are materials that don’t
have a safe therapeutic dose.
Lead’s a good example. There is
no dose so small that we know
in which lead is not dangerous.”
To test the toxicity of a substance,
scientists use a method called
the lethal dose 50%, or LD50.
It’s the amount of a substance needed
to kill 50 percent of a test population,
which is usually rodents.
This quantity can then be extrapolated
into how much it would take to kill a person.
For example, the LD50 of water is 6 liters
for someone weighing about 165 pounds.
That means if you weigh a buck 65 and
guzzle about one and a half gallons
of water all at once, you’re toast.
So don’t do that.
While on the other hand, there are
some poisons out there that can kill
instantly with a way smaller dose.
Cyanide is the perfect example.
“We have a lot of experience with poisons
killing people because we’ve killed
a lot of people over our homicidal history
and so cyanide causes an almost
instantaneous destruction of the enzymes
that process oxygen in your cells.
You suffer a very rapid chemical suffocation, it’s
damaging the nerves so quickly, you may convulse.
So a poison that attacks the central nervous
system is going to kill you a lot more quickly.”
So a dose of cyanide pretty much
certifies you as immediately dead.
But there are other poisons that take a long
time to finish the job and are nearly undetectable.
For example, in 2006, Russian spies
poisoned ex-KGB agent Alexander Litvinenko
with radioactive polonium-210.
“There were assassins from Russia that
had put polonium 210 in his tea.
It’s tasteless so it’s a great poison.
I mean he was desperately starting
to be sick within a few hours, but
it took him quite a while to die
because it’s a radioactive poison,
it moves through the bloodstream,
deposits in the bones,
and it starts just emitting radiation
from where it’s lodged so you get
this slow cook of the radiation.”
Litvinenko, although having symptoms
within a couple hours, took around
three weeks to die from the poisoning.
And toxicologists nearly didn’t even figure it out.
You have to know to look for polonium-210
or else you’ll miss it in an autopsy.
It just goes to show you,
there really is an incredibly
diverse array of poisons out there.
In fact, much of the chemists’
beloved periodic table is poisonous.
Just how much you ask? Deb, take it away. “Haha!
Man, so much of the periodic table is poisonous.
There’s antimony, there’s copper poisoning,
you can actually poison yourself with copper.
You can poison yourself with…
well, nickle’s not so bad,
but you can poison yourself
with other radioactive elements.
You can poison yourself with gold,
gold is really toxic.
You can poison yourself with silver,
but you’ll only turn blue.”
That’s right Deb you turn blue,
but with enough of it, you can die.
But even though there’s poisons everywhere,
it’s really not that much of a problem.
Like with water, what gives life
can also take it away.
Some of the world’s most powerful medicines
are also poisons at higher doses.
So don’t lock yourself away in fear of poisons,
step out into the world with an appreciation
that chemistry like every science
has a dual nature.
Check out Deb’s amazing book
“The Poisoner’s Handbook”,
the link is in the description.
And also, don’t forget to subscribe
and we’ll see you again soon.