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  • Part of this video was sponsored by LastPass. Stick around to the end for a

  • word from our sponsor.

  • Are negative ions good for you?

  • Normally I'd dismiss such a question out of hand.

  • In fact that's exactly what I did when a friend brought

  • it up about a month ago. But he was insistent he said no this is for real

  • there's science behind it.

  • And so I looked into it and I found this.

  • There are literally hundreds of published peer-reviewed scientific studies on the

  • biological effects of ions.

  • It's a body of research that begins about a century

  • ago and continues to the present day.

  • And this is just a fraction of it.

  • Now these studies aren't just about any old ions they're about atmospheric ions or air

  • ions. And although the results are not uniform, they all begin with the premise

  • that positive ions make us feel bad and negative ions make us feel good.

  • So in this video I want to get to the bottom of this.

  • These are Himalayan salt lamps.

  • With the heat from the light bulb, it releases negative ions into the air and of

  • course negative ions are what you breathe in and produce the serotonin in

  • the body and in serotonin is like the primary neurotransmitter in your whole

  • body and all living things and that's what makes you feel good...

  • awesome.

  • Can I jump in here for a second. When I first heard all this business

  • about atmospheric ions, my first thought was 'why should we expect there to be

  • many ions in the atmosphere at all?' I mean to recap, an ion is just an atom or

  • a molecule that has gained or lost an electron. If it loses an electron it's a

  • positive ion. If it gains an electron it becomes a negative ion. But here's the

  • thing: unlike charges attract. So moving about in the atmosphere I'd

  • expect the positive and negative ions to find each other and then BOOM they're

  • back to being neutral.

  • However, as it turns out there are some processes that

  • are constantly generating atmospheric ions.

  • For example cosmic rays. These are

  • highly energetic particles from across the universe that slam into our

  • atmosphere and transfer their energy to the air, creating ions in the process.

  • Cosmic rays are thought to create around 500 ions per cubic

  • centimeter at ground level. In fact they're the most significant source of

  • ions generated over the oceans.

  • But here on land there are other sources of

  • ionization, things like natural radioactivity.

  • There are these long-lived

  • isotopes of uranium and thorium and their decay products that can spit out

  • highly energetic particles in the form of alpha, beta and gamma rays.

  • These ionize the air and they vary widely from place to place but they can contribute

  • hundreds up to many thousands of ions per cubic centimeter.

  • If you were to recommend one of these to me that like has the most negative ions, er, which one

  • do you think?

  • I would just go for which one's hottest. -yeah?

  • Because it's the heat from the lightbulb that creates the heat, which makes the reaction in the salt.

  • Got it.

  • Wow! This one's great. Yeah? This would just be perfect

  • And then you have thunderstorms. Each lightning strike generates copious

  • amounts of ions.

  • Perhaps one of the more surprising sources of negative ions is waterfalls.

  • As water droplets collide with each other or with wetted surfaces

  • with high velocity, the water molecules create this electrified spray with

  • negative ions that can be transferred to the air around it.

  • Depending on your distance from the waterfall, ion levels can reach tens of thousands of ions per

  • cubic centimeter. And the same effect occurs with ocean waves crashing on shore.

  • Hello! Hi Derek, how are you?

  • Good, Can I give you that? Sure.

  • So what I want to know is how many negative ions are there coming off that lamp when it's on?

  • We have a technique involving mass spectrometry that measures negative ions coming off

  • of solids and so we can give it a try.

  • Are you an ion expert? I've been studying

  • ions for 55 years. Whoa

  • And have written hundreds of papers on all

  • aspects of ions.

  • So this is my salt lamp. it's meant to give us lots of negative

  • ions. Can you tell me whether it's giving us some negative ions?

  • We're gonna have a look and the thing we're utilizing here is that the inlet to this mass

  • spectrometer is at atmospheric pressure and if there's ions there we'll be able

  • to detect them. So this is like.. is it is it kind of like an electronic nose or

  • something for ions? sniffs the ions. - You could think of it as a nose for ions. Yeah, yeah, sniffs the ions. -OK

  • The lamp is next to the ion sampling cone. I mean it's not on yet but we'll see

  • if there's any ions coming from it. -No so this display here this would be this

  • is our mass to charge axis here so how how heavy they are in molecular

  • weight essentially and if there's ions being formed we're gonna see some signal

  • on this screen. -There'd be like some peaks? Some peaks, yeah

  • Now does it need to warm up?

  • er -I think that's the idea, yeah.

  • Now there are some places that do naturally

  • have lower concentrations of ions, namely the interiors of houses and businesses.

  • Because these structures provide some shielding from the cosmic rays and from

  • the natural radioactivity. Plus if you have metal ducting and air

  • conditioning, well some of those charged ions will get stuck in the ducts

  • so typically levels inside homes and businesses can be as low as around 100

  • or 200 ions per cubic centimeter.

  • Ion concentrations are also typically lower

  • in polluted areas, in big cities or around factories. And that's because the

  • ions actually cling to those pollutants or the aerosols and so they

  • don't live as long in the atmosphere.

  • So the assertion that we live in

  • environments with fewer ions than our ancestors is true.

  • If you're thinking that you feel better around waterfalls and oceans and after

  • thunderstorms than you do in polluted cities or around big factories, well

  • maybe that's the reason why scientists have been studying the effects of

  • negative ions on human health for nearly a century.

  • So let's consider the evidence...

  • In one study people suffering from seasonal affective disorder were

  • randomly assigned to one of three treatment groups: bright light therapy

  • high concentrations of negative ions or low concentrations of negative ions.

  • They found that both bright light therapy and high-density negative ions independently

  • produced antidepressant effects, but not low density negative ions.

  • In another study, participants in a high-density negative ion environment had significantly faster

  • reaction times and reported being more energetic than those in an ambient air control.

  • Now if all this sounds too subjective, EEG experiments showed people

  • exposed to high-density negative ions had a slower alpha wave frequency with

  • higher amplitude. Participants also reported increased relaxation, alertness,

  • and improved working capacity. And opposite results have been found with

  • positive ions. In one study volunteers were exposed to high concentrations of

  • positive ions for two hours. Symptoms of anxiety and excitement significantly

  • increased. During the time of exposure serum serotonin levels also increased

  • significantly. This has even been taken into real-world work environments. An

  • air ionizer was fitted to the air-conditioning unit in an office

  • building and periodically turned on and off over 12 weeks. When the ionizer was

  • pumping out negative ions, workers reported 50% fewer headaches. They also

  • reported increased alertness, perceived atmospheric freshness, and environmental

  • and personal warmth. It's feeling it's feeling pretty hot it's been on for an

  • hour? yeah. So the question is can a salt lamp generate negative ions? let's check

  • for negative ions? -let's look again

  • Doesn't look like it.

  • But, I mean there's not even like a background.

  • No, there's not... it's just like

  • it's not even sitting there.

  • So your conclusion after testing this device is

  • that it's producing no negative ions. -We're certainly not able to detect any negative ions.

  • The idea for how these salt lamps are meant to create negative

  • ions is that water molecules are meant to land on the surface and liberate

  • chloride ions from the lattice.

  • But ask any chemist worth their salt and they'll

  • tell you the energy required to do this is way too high so it just doesn't

  • happen.

  • What I find ironic is that there are crystals which when heated will

  • produce ions. It's just that salt doesn't have the

  • right crystal structure to make this work. The gemstone tourmaline does.

  • Those samples are worth many thousands of dollars.

  • Tourmaline has a structure such that if you heat it and cause it to expand, it will actually

  • develop an electric charge on the faces of the of the crystal you have

  • discharges between those faces, breakdown in air and forming ions and that

  • charge then can get transferred to any organic molecule that's present in the air.

  • A five degree change was enough to generate ions. -I just find this

  • extraordinary that there is a crystal, there is a material that you could heat

  • up and create negative ions. So the reason people wouldn't have tourmaline

  • lamps is because tourmaline is just really expensive?

  • okay so we didn't get

  • any ions off of the salt lamp but I brought something along that I think

  • might give us some ions. This is an ionic air purifier. When this product was first

  • launched it sold a two million units. It works by using high voltage to ionize

  • the air and accelerate those ions to produce the light breeze you can feel

  • without any moving parts. -Okay I feel a breeze coming out of it

  • and that should be going into the nozzle? we've got it pointed right at our ion

  • Inlet so that's good.

  • We seem to be seeing some ions at the moment and we

  • have the ionic breeze right up next to the source so.

  • These are negative ions

  • these are negative ions.

  • So if you want negative ions what you need in your

  • house is not a salt lamp, it's an ionic air purifier.

  • Before you rush out to buy

  • one I should warn you that generating these ions produces an unfortunate

  • by-product:

  • ozone. So right now we're measuring about 17 parts per billion

  • actually of ozone. So let's put this up to the front and see whether or not

  • we see an increase in the amount of ozone.