This shiny metal is always in a liquid state.
It's much denser and heavier than water.
And if you jumped into a pool
full of this stuff,
you'd instantly regret it.
The metal I'm talking about
is liquid mercury.
Yeah, swimming in it
would feel like swimming in Jell-O.
Only worse because it would burn
and seriously irritate your skin.
And if you stayed in the pool long enough,
liquid mercury would get absorbed
by your skin and make it to your organs.
Even your brain.
Eventually, it could cause
speech difficulties
and lack of coordination.
You could lose your vision too.
And if you think this is bad,
you haven't seen the worst on our list yet.
Buckle up as we submerge you
in the most dangerous things
known to humanity.
From painful stings
to severe frostbite,
this journey could get fatal quick.
Think you can make it till the end?
Well, for your next dangerous dive,
let me take you to Tanzania.
Here, there's a lake so dangerous
it could turn you to stone.
Huh?
Yeah, that's right.
Lake Natron has uncomfortably high pH levels.
All thanks to being too close to an active volcano,
Ol Doinyo Lengai.
This volcano spews out a rare kind of lava
rich in sodium and potassium carbonate.
And mix this stuff with water
and you've got yourself a mummification pool.
After only five seconds in Lake Natron,
you'd get third-degree burns.
That's because this lake
can get as hot as 60 °C (140 °F).
And don't swallow any of its water.
Because Lake Natron could burn your insides.
If you couldn't get out of this hot water
and stayed submerged long enough,
your entire body would calcify and harden.
Lake Natron would preserve you so well
that even one hundred years later,
people could find your hair
and what's left of your organs intact.
OK, let's take it up a notch
and throw you into something even more dangerous.
Like a pool full of stingrays.
These guys might look cute,
but don't let them fool you.
They're armed with long, venomous stringers,
ready to kill you at any moment.
If you were stung by a stingray,
the venom would flow into your bloodstream.
And it would hurt.
A lot.
That's because of the serotonin in a stingray's venom.
It would cause your muscles to contract badly.
Now imagine
being stung by a pool full of these creatures.
Not only would you feel as if
your body was twisting all around,
but you could also experience a severe allergic reaction.
In that case,
you'd require proper medical attention immediately.
But luckily for you,
stingrays wouldn't go after you
unless they felt threatened.
So just try not to disturb them,
and you'll be fine.
Likely.
Most likely.
Probably.
You know, when it comes to swimming with creatures,
you could do a lot worse.
Have you ever swam in a pool filled with sharks?
Well, you're about to give it a try.
Yeah, sharks can smell your blood.
They can also hear you very well.
Their hearing is on par
with their amazing sense of smell.
But now, if a shark took a bite out of you,
Well, it doesn't necessarily mean it wanted to harm you.
Sharks are just extremely curious.
And they use their teeth like you use your hands.
They investigate their surroundings by touching things around them
with their teeth.
That's weird,
and it really would be unlucky for you
to get stuck with a curious bunch of sharks in one pool.
But the chances are they wouldn't be interested in you at all.
Sharks are wired to hunt fish
and you'd be a lot bigger than most sharks anyway.
So they might be scared of you
more than you'd be scared of them.
As long as you don't make any sudden movements,
you could get out of that pool unharmed.
But I can't say that about the next item on our list.
Volcanoes.
Active volcanoes are hot.
I'm talking 500 °C (932 °F) hot.
And as you stand on the rim of one,
you'd be breathing in a ridiculously hot mix of gases
like sulfur and ammonia.
That alone would cause you to pass out.
But things are about to get worse.
As your unconscious body hit the magma inside a volcano,
the impact would be so hard
that it would break most of the bones in your body.
Your skin would be flaming,
your lungs would get seared.
But contrary to what you might think,
you wouldn't sink.
That's because magma
can be thousands to millions of times more viscous than water.
Oh, but there's one more thing.
Within seconds,
the intense temperature inside a volcano
would make you go poof.
Yeah, you'd ignite into a ball of flames.
And only your bones would be left.
But not for long.
OK, I think it's time to cool off
as you prepared to take the number one most dangerous dive on our list.
A dive in a pool of liquid nitrogen.
Liquid nitrogen is nonflammable.
It has no odor and no color.
And it makes a ton of fun fog
when you expose it to room temperature air.
So why is it the most dangerous thing on our list?
Well, for starters,
liquid nitrogen would displace oxygen around the pool.
Yeah, you wouldn't be able to breathe
and might pass out before you have a chance to feel anything else.
But that would be just the beginning.
This stuff boils at a very low temperature of -196 °C (−320 °F).
So if you took a swim in a pool of liquid nitrogen
longer than a few seconds,
you wouldn't be coming back out.
You would get severe frostbite all over your body.
Your muscles, fat and blood would be frozen solid.
If you managed to stay conscious
and kept your head above the surface,
your body would freeze and sink right down.
But there's good news.
Since you would instantly turn into a human popsicle.
you'd also experience extreme nerve damage,
meaning you simply wouldn't feel any pain.
"Why you do this? I feel no pain."
You would just drown in a freezing cold boiling nitrogen pool.
And that's why it's number one
on the list of things you don't want to jump into.
But hey, some journeys might be worth the risk.
Like a jump in the deepest hole on Earth.
But that's a story for another WHAT IF.