Let’s say you’re going for a hike and out of nowhere an attacker appears.
You don’t know krav maga and you’re not a bear so how are you going to protect yourself
if things get ugly?
Chemistry--in the form of pepper spray.
Pepper spray is no joke.
This stuff is designed to hurt and it’s so effective that a single blast can reportedly
debilitate a person for upwards of an hour.
Let’s take a look at what’s going on in this weaponized hot sauce that gives it its
sting.
The active ingredient in pepper spray is capsaicin, which comes from peppers.
But how is pepper spray THAT intense?
I can jam a jalapeno in an attacker’s eye all I want but it’s not going to do a whole
lot.
To go from this to this, chemists finely grind up a whole bunch of peppers from the Capsicum
family, then use ethanol to extract the capsaicin.
Next most of the ethanol is evaporated off, leaving behind a sticky oily residue, more
formally known as oleoresin capsicum.
This residue is mixed with propylene glycol and water.
The propylene glycol causes the capsaicin to form little droplets that mix throughout
the water, making a capsaicin/water emulsion.
Think of it as an oil and vinegar salad dressing -- except with smaller droplets designed to
inflict pain.
It’s is then packaged into a spray can with a propellant and boom--pepper spray.
We have an video on how capsaicin works and why it triggers that burning sensation.
Check it out here.
Pepper spray is especially painful when it comes into contact with mucus membranes in
our eyes, nose, and mouth.
And just like with many other things, it’s the dose that makes the poison: the more capsaicin
you get in your exposed to, the more you’ll feel the burn, and pepper spray can have 10
times the capsaicin concentration as a habanero seed… or more.
Ouch.
Once someone is pepper sprayed, the capsaicin immediately triggers distress signals to the
brain essentially saying “Help!”
Your body forces your eyes shut, produces streams of tears, and buckets of mucus.
All to try and protect against more injury and flush the capsaicin away.
At the same time the capsaicin inflames the skin around your eyes.
It also stimulates nerve endings in the throat and spasms of the larynx, making it hard to
talk.
The pain has been described as feeling like “thousands of pieces of glass shooting into
your eyes.”
Sounds fun.
So now let’s say you accidentally got pepper spray on yourself.
Here’s what you need to know.
First, do not touch your face.
You’re just going to spread the capsaicin around and make the pain worse.
To get this stuff off you’re going to need something that’s nonpolar, since capsaicin
is nonpolar.
You’re thinking milk’s the answer, aren’t you?
It’s not.
While milk does contain nonpolar fats that can dull the burn, dumping it in your eyes
isn’t the best idea since it’s not sterile.
What you really need is one of these.
The solutions are sterile, and they contain a salt like magnesium hydroxide, which cause
the capsaicin molecules to be released from their emulsified prison and makes them easier
to rinse off.
Just make sure not to grab a mint flavored antacid--menthol can make the pain worse.
Yup science shows mint-sprinkled hot wings might be fusion food too far.
Ideally you’d then flush your eyes out for at least 15 minutes at a wash station, but
chances are if you’ve been pepper sprayed, you’re not gonna have one of these right
next to you.
So just use as much water after the antacid as you can.
Now that you’ve flushed out your eyes be sure to *thoroughly* wash your hands with
a mild soap like liquid dish detergent.
After all that you don’t want to accidently re-contaminate your eyes with any residual
capsaicin from the pepper spray.
But we hate to break it to you - one study suggests that depending on your own physiology,
the best way to get rid of the pain is … just to wait it out.
Once the pain subsides and you can see again, consider seeing your way to a doctor, just
to make sure everything’s OK.
Well we hope you never have to use it, but when worse comes to worst the chemistry packed
into that little canister can give you enough time to get out of a dangerous situation…
and live to learn about chemistry another day.
Be sure to check out our video on how capsaicin works and make sure to hit that thumbs up
on your way out.
We’ll see ya next week.