Blessed by the Potato

I’m disgusted by this article in the Huffington Post. I’ve been warned about that rag and the quality of their science knowledge (worse than none) before, but it became the topic of some discussion over at PriusChat, and I had to check it out for myself. Note that I have ranted on this subject before.

The author describes her experience buying a Prius, after which she experienced headaches. She took the car back to the dealer, got a Highlander instead, and the headaches went away.

If that was all there was to it, it’d be fine: a weird anomaly, who knows why it happened, but her problem is solved so good for her.

But that wasn’t all there was to it. Because the Prius is a hybrid, she immediately jumped to the conclusion that somehow, the magnetic fields were causing her headaches. She then goes on to insinuate that these same fields caused “inflammatory” issues and a brain tumour in people she knows who happen to drive hybrids.

This is not evidence, it’s not science, it’s fearmongering of the worst sort.

To try to add weight to her arguments, she got a “meter” and tried taking some measurements of the magnetic fields on her own. And you know what, the only thing the general public fears more than magnetic fields are numbers, so you can bet that went well. She obviously did not know how the meter (or magnetic fields) work, because she only gives one number in the article.

Here’s the thing about magnetic fields: they’re kind of like sound. You have a frequency, and a strength. So to say you have a sound of 70 dB, or a magnetic field of 2 mG, doesn’t fully describe it. You’d also want to know if it was a deep bass thrum, or a middle C, or so many Hz for the magnetic field. And she doesn’t say that anywhere.

That gets particularly important when she pulls out this mystery meter. I’ll bet you dollars-to-doughnuts she’s trying to use a cheap “trifield” type survey meter, that only has a little dial readout for showing field strength. These are meant to be used around power line fields where you know the frequency you’re dealing with in advance, and they give very screwy results when presented with fields of unknown frequency and transients. Unfortunately, all we can say about the fields present in a car is that they are highly unlikely to be 60 Hz powerline fields.

Often, these meters are induced-current based, so if you have a 1 mG 60 Hz field, it shows up as 1 on the meter. But, if you have a 1 mG 600 Hz field, it shows up as 10 on the meter. So when someone who is unskilled at science or numbers — or much of anything really — gives a number in an article, I have basically zero faith that that number represents what they think it represents. For example, she says that just turning on the Nav and AC system in her car increased the field almost as much as the hybrid drivetrain did, but that makes little to no sense, on many levels. First off, the nav and AC shouldn’t draw nearly as much power as what’s needed to move the car (though all of these are well-shielded in a hybrid), so the measurement shouldn’t have gone as it did. And even if that was the case, it would mean that the nav and AC should be just as much a cause of her headaches as the hybrid drivetrain if she believes magnetic fields are responsible. She shouldn’t be out on a crusade against hybrids, but against in-dash nav systems!

She justifies getting a nav system in her Highlander by saying that the slightly smaller Prius “compacts” the fields, again showing that she doesn’t understand how things work — the extra space in the SUV is wasted, the design constraint still puts the nav system at arm’s reach for the driver.

She then goes on to insinuate that hybrids pose a health danger, remarking that “I started to wonder about my clients who drive hybrids. Every one of them has an inflammatory issue that baffles me…” Her byline says that she’s “Yoga, health expert”. What do you want to bet that every one of her clients, no matter what they drive, has “an inflammatory issue”?

The conclusion though was the biggest tip-off for anyone remotely familiar with the FUD surrounding hybrids that she was not a source to be taken seriously: she repeats some of the nonsense about the batteries and Sudbury, that has been debunked many times (including here), clearly indicating that she has not done her homework.

Scientific articles have peer review systems to try to catch these kinds of glaring errors, and those occasionally do fail (recently, our group tore apart an article, providing 3 pages of corrections, and the other reviewer said simply “it’s fine”). But the mainstream media, which should be more careful since it deals with a more credulous audience, often has much more glaring mistakes present — perhaps because journalists are equally credulous when it comes to technical matters.

All that said, we return to the issue of her headaches. It’s been said that we can’t disagree with the fact that she experienced headaches that went away when she changed cars. I’d say that we could disagree with even that level of evidence (did she make it up to get a controversial article out that other people would cite, even if just to debunk her?), especially given how subjective and random headaches can be. But, let’s grant that her headaches did happen, and even that they went away with the change in cars. It could be that the headaches were unrelated to the car itself, and could have been due to the stress of buying a new car, worrying about finances, etc., and would have gone away in a few days/weeks anyway. But even if we grant that somehow, the headaches were due specifically to the car, that does not lead us to blame the hybrid transmission and/or magnetic fields. There simply is no evidence of that. She had an individual problem, and she solved it by changing cars, and that’s great for her. But it’s misleading to then go and blame one specific aspect of the car without any evidence. She could have been allergic to the ecoplastic used in the dash, or to a host of other things. My favourite theory revolves around the rearview mirror: the Prius is a great car and I love it, but the rearview mirror is horribly low. I’m constantly ducking my head to look under it to check for pedestrians as I make a right turn, and if she was doing the same that repetitive head-ducking motion could have given her a headache. Or, similarly, the rear spoiler splits the rear window, at just about the height most cars’ headlights fall. If she’s driving down even a moderately bumpy road, their lights would constantly strobe to her point of view as they disappear behind the spoiler and reappear above or below it.

There are numerous reasons why this car in particular could be giving her headaches, and unless she’s willing to get back in it for some experimentation, we can’t say what factor could be responsible (if any). It brings us back to the issue of placebos: for an individual person, a placebo may work to solve their problem, such as a headache. They may be willing to pay money for a placebo (e.g., a homeopathic tincture). On the individual level, that’s fine: do what you need to do to solve your individual problem. But on a societal level, we don’t want to ascribe efficacy to what we know are really just placebos and have them for sale in our pharmacies, because it’s not good science, and it’s not good policy. Likewise, we don’t want to go around banning things like cell phones and wifi and hybrids without evidence that they are indeed causing harm (and if she’s afraid of hybrids, man, wait till she sees some of the controversy over cell phones!).

Finally, a quick repeat of my note on risk vs benefits. We know that hybrid cars have demonstrable environmental and financial benefits. We know that they can reduce our individual exposure to known carcinogens (e.g.: diesel), and our societal exposure to other pollutants. We don’t have good evidence that they even do have increased magnetic fields inside of the passenger compartment, and if they did, whether those fields would be harmful. The risk-benefit right now is highly likely skewed towards there being a worthwhile benefit, but because people are so afraid of the unknown, the unknown risks are large in their minds, and lead to articles like this one.