Want a good lesson on how not to make thoughtful healthy decisions about risk? Take a lesson from what Health Canada just did. It is a classic example of how our emotional risk perception system can cause us to do really dumb things in the name of keeping ourselves safe.

You know citronella, that familiar lemony-smelling summer time mosquito repellent? It’s in those candles you burn around the pool or the barbecue to keep the bugs away. It’s also used in some bug sprays, for the same reason. (It’s a natural derivative of lemon grass.) But Health Canada has banned the sale of citronella bug spray. Not because there is any serious evidence that it might be harmful. No, this ban is because there is no absolutely conclusive proof that it’s safe.

There is dumbness here at so many levels. First of all, the basic risk standard of proving that something is absolutely safe, while emotionally appealing, is nuts to any objective thinker. You can’t prove a negative. You can’t absolutely prove that something doesn’t cause harm. Health Canada says there are suspicions that citronella oil may contain trace amounts of another natural chemical that may cause cancer and reproductive problems in lab animals exposed to super high doses, way higher than what we we’re exposed to.

But citronella has been as an insecticide in use since just after World War II and there is NO evidence that it does those harms to people. So Health Canada is basically saying to citronella spray sellers “Until you can prove it doesn’t do what it has never been shown to do in more than 70 years, you can’t sell it.” Like I said, proof of safety may feel like a nice protective standard, but consider all the things in the real world we’d have to give up if that were the standard everything had to meet. Dumb # 1.

Dumb # 2 is the inconsistent way Health Canada, and the U.S. and the EU and Japan and most countries, treat the risk of pesticides. (A pesticide is anything that kills whatever we call a pest; insecticides kill bugs, herbicides kill weeds, fungicides kill mold, etc.) Health Canada has NOT banned the use of citronella in candles, or perfumes, or soaps. These sources expose our skin and lungs the very same stuff just as the bug spray does. If there is a risk from one application, it’s there in the others. Why ban only the spray?

Because the rules for pesticides are different, the standards much higher. Why? In part because the word “PESTICIDES!!!” has become so negatively stigmatized that whenever we hear it, we worry about anything associated with it. And we demand that the government protect us. As a result, governments around the world have tighter rules for “pesticides” than for many other potential hazards that could be even greater. For instance, the rules are much less restrictive for the natural products we use to repel pests, like citronella, that are sold in forms (like those candles) that don’t qualify under the ‘pesticide’ rules. Different rules for different risks, all of which potentially threaten us equally, but some of which scare us more. Dumb # 2.

And then there is the lesson of excessive fear because of uncertainty. As researchers in risk perception have found, when we can’t detect something with our senses, or we don’t understand it because it is scientifically complex, we don’t know what we need to know to protect ourselves. That uncertainty leaves us feeling powerless, unable to keep ourselves safe, and that feeling of powerlessness makes any risk scarier. Pesticides, and indeed most industrial chemicals, can’t be detected with our senses and involve some complex hard-for-most-of-us-to-understand toxicological risk details.  Lots of uncertainty. Against that natural protective instinct, we want certainty, proof, a guarantee that there are no lurking dangers we don’t know about.

So Health Canada has adopted a super precautionary approach, at least towards pesticides and industrial chemicals, which essentially says that while any uncertainty remains, a substance or process or product is banned. Again, that sort of precaution feels safe, but consider what we’d have to give up if such a standard – absolute and certain proof of safety - were applied against all the substances and processes and products in our modern lives. Dumb # 3.

We all do this same thing in our own personal lives, make decisions and choices about risk based more on how things feel than what makes the most sense if we just looked at things objectively, without all our instincts and emotions and values clouding our view of the facts. I do to. I worry too much about some things – riding as a passenger in car while the driver is talking on her cell phone – and not worrying enough about others things – like talking on my cell phone when I drive. But I know those choices can sometimes get me into trouble and expose me to risks all by themselves. The challenge is to recognize this threat of worrying too much or too little, the risk that sometime arises from the way we perceive risk in the first place, and try and overcome it with a little more careful thinking, in the name of making smarter, healthier choices.

Thank you, Health Canada, for providing one more lesson that might challenge us to think a little more carefully about how to keep ourselves safe.