, ,

Longtime listener, big fan (please please please get someone on to talk about safe spaces and politically correctness), but I’m writing because a recent episode changed my opinion of Jill Stein. I used to think she was a smart person pandering to lefty conspiracy theorists.

Now I think she herself is a fan of pseudo-science, and lacks a basic understanding of how the world works. The tipping point was her stance on WiFi: Stein thought it was a plausible health risk, and should be looked into.

That’s ridiculous.

Let’s start with the intuitive argument. Shove your way towards your wireless router or cable modem, and look at the power cord which plugs into the back of it. Pretty small, right  Mine’s about as thick as a headphone cable. 100% of the router’s power comes through that cord, so that sets an upper limit for how much energy it can emit.

Now I want you to check the power cords for other devices that emit electromagnetic radiation (or EMR), such as your microwave, electric stove, lamps, and television.

Oh sorry, you didn’t know that microwaves, infrared, and visible light are all forms of EMR? It’s true, all of them are transmitted via photons, they only differ in the amount of energy they pack per photon. Yes, even stoves emit EMR. All of them draw power from the same outlets as your router. Now, what do you notice about their cords? All of them are thicker, in some cases substantially more. The energy a cable can carry is proportional to the area of its cross-section, too; double the diameter, and the capacity quadruples.

Admittedly, this cable test is pretty crude; most of a stove’s heat is delivered by physical contact, not radiation, your microwave is shielded so nearly all the EMR it emits are contained, and your lamp cord was probably designed to fuel a power-hungry incandescent bulb and not a low-energy compact-florescent or LED. But it’s a handy ballpark that suggests you should be more worried about nearly every other device in your house.

Besides, we can put numbers to the rate of energy consumed.

Device Watts
Wireless router (TP-Link WR702N) 0.8
40-watt equivalent LED light bulb 8
Wireless router (Asus RT-AC68U) 10
40-watt equivalent Compact Florescent bulb 10
100-watt equivalent LED light bulb 20
Samsung HL-T7288W 72″ HDTV 230
Small microwave 500
Small oven 1000
Large microwave 1500
Large oven 3000

Those numbers are misleading, too; your wireless router is also a computer, which sucks away a decent fraction of the incoming power, and if it also doubles as a cable or DSL modem it consumes some energy to transmit data across those wires. WiFi power usage varies dramatically, and while it’s typically 0.1 watts it tops out at 1 watt (though “omnidirectional” antennas can feed you 4 watts if you’re in the right spot). In fact, your smart phone’s screen emits more EMR than its antennas when active! So you should be more concerned about the radiation dose you get from the nearest lightbulb, even if it’s one of those ultra-efficient LED ones.

Heck, we can go further. The typical human being outputs roughly 100 watts of EMR. You get more radiation by hugging someone than from your WiFi router! At the Earth’s surface, the Sun is directly or indirectly responsible for about 1,000 watts of radiation per square metre. If the average woman stands on her toes outside on a sunny day, she’s getting a dose of 1,500 watts of radiation.

Device Watts
Typical WiFi power output 0.1
Maximum WiFi power output (overall) 1
Maximum WiFi power output (directional) 4
40-watt equivalent LED light bulb 8
40-watt equivalent Compact Florescent bulb 10
100-watt equivalent LED light bulb 20
Human being 100
Samsung HL-T7288W 72″ HDTV 230
The Sun 1000

“Aha,” I hear you say, “but we know sunlight harms you!” Quite true, there’s more to this than just power levels. Damaging something by slow weathering is quite different from tossing a rock at it.

The relevant rock is known as “ionizing radiation:” the photon hits an atom with enough force to knock out an electron off. This attracts it to bonds where it can fill that hole, changing how it interacts with other atoms. That’s usually a bad thing.

Since we’re dealing with atoms, we’re playing by the rules of Quantum Mechanics. The “quantum” part is because everything is quantised. Think of those “you must be this tall” markers at carnival rides; if you are taller than that line, you can ride, otherwise you cannot. Two small children arriving right after each other cannot ride, even if the sum of their heights would have been well above that line. It’s a simplified analogy, but accurate at the scales we’re discussing.

So how much energy does a photon need to be ionizing? A trip to Wikipedia suggests 3.1 electron Volts is a conservative figure, but that’s a meaningless quantity for most of us. I’ll just assign it a value if 100%, to make comparisons easy. The energy of a photon is determined by its wavelength or frequency, which makes filling in values easy.

Type of Photon Peak Wavelength eV Relative
WiFi (low band) 12cm 1.0332E-05 0.00033%
Microwaves 12cm 1.0332E-05 0.00033%
WiFi (high band) 5.1cm 2.43106E-05 0.00078%
Human radiation 9500nm 0.13051 4.21000%
Stove (375 Fahrenheit) 6250nm 0.198375 6.39919%
Stove (450 Fahrenheit) 5740nm 0.216071 6.97003%
Red light 700nm 1.7712 57.13548%
Pseudo-ionizing radiation 400nm 3.1 100.00000%
Blue light 390nm 3.17908 102.55097%
FCC-defined ionizing radiation 124nm 10 322.58065%

WiFi is nowhere near ionizing, at least by itself. During my earlier analogy, however, I bet you imagined one kid sitting on another’s shoulders to get past the height restriction. That’s a valid move: if a WiFi photon happens to hit an atom at exactly the same time as something else, the combined energy of the two could be enough to knock out an electron. This is a very rare event, given how sparse the subatomic realm is, but “rare” isn’t “impossible.”

But if WiFi only has 0.00078% of the power needed, the second photon has to contribute the remaining 99.99922%. Anything that could generate a photon that powerful could probably generate one with 100% of the power too. You need a source of ionizing radiation in order to boost WiFi to the ionizing level! Blaming WiFi for this is like blaming a baseball cap for putting a kid past the “you must be this tall” mark, except for the analogy to fit the baseball cap has to be thinner than a single wool fibre.

“But hang on, what about that study Jill Stein cited?,” I pretend to hear you say. Ugh, don’t remind me; I did some coverage of that study earlier on, and I regret not finishing it. Still, read through what I typed up and you’ll get a feeling that study is deeply problematic. If you’d rather not, here’s a teaser:

As one of the reviewers noted, it’s very easy to fish for correlations with so many variables in play and so many different ways to slice the data. If the typical study has a 30% chance of finding a false positive for a single variable, there’s a 31% chance two of the five metrics will have false positives. The typical study has a false negative rate of about 45%, though, while one of the reviewers noted this study’s was over 95%; while false positives and false negatives are only loosely related, it’s a safe bet that my above back-of-the-envelope calculation is an underestimate.

Let’s riff off that with some basic Bayesian stats. If the odds of a random substance actually being cancerous are 5%, the odds of this study getting a false positive are 5%, and the odds of this study getting a false negative are 95%, then the odds of cell phone radiation being cancerous, given that this study found it to be cancerous, are… 5%.

I’d actually have more respect for Jill Stein said she believed vaccines are harmful, because that’s more plausible than thinking WiFi is a health hazard.