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Tens of millions of gallons of crude oil leak into the ocean every day. Naturally, from the sea floor. Why is it so much worse when far less oil comes from a hole dug by humans? The psychology of risk perception offers an explanation.
Let's say you notice that every time you smell that great smelling flower in your neighbor's yard, you get a little boost in your memory. You realize that this could benefit not only to mankind, but your bank account, so you buy some of these plants at a local garden shop, harvest and dry the leaves, and put them in a box with some rainbows and crystals and blue skies on the label and call the product "Nature's Own Memory Enhancer". You could take that to any local store that sells vitamins or herbal supplements, and have it on sale the next day.
Now let's say that your dog was diagnosed with cancer but after he chewed on the leaves of that great smelling plant in your neighbor's yard, the cancer disappeared. You take some of the leaves of this plant to a friend who works in a science lab, who takes the oil from the surface of the leaves and puts it in a petri dish with cancer cells, and the cancer cells die. You may have a cure for cancer! But unlike the "natural" product, it would take you a decade and hundreds of millions of dollars or research before you could put a version of your neighbor's plant on the market in the form of a human-made pharmaceutical.
Why is that? Why do we have such stringent rules for human-made biologically active substances, and practically none for "natural" biologically active substances? The answer comes from research into risk perception, which has found that natural risks are less scary than human-made ones. It doesn't matter how big or small the actual risk is. A natural one is just less frightening. People who fret over all sorts of human-made radiation - from nuclear power or cell phones or power lines - don't freak out about radiation from the sun, which kills 8,000 Americans a year from melanoma skin cancer. A California community trying to choose which insecticide to use to spray for West Nile virus mosquitoes had to chose between a synthetic one that was slight less toxic to humans, and a natural one that was more toxic. They chose the natural, more toxic one. Greenpeace worries about genetic engineering because "...it enables scientists to create plants, animals, and micro-organisms by manipulating genes in a way that does not occur naturally" (my emphasis). UN-natural is scarier, per se.
It's not as though nature isn't often red in tooth and claw. Soy is far more estrogenic than Bisphenol A, the ingredient in plastic bottles and the lining of food cans suspected of interfering with the hormone levels of pregnant mothers and causing a range of health problems in the developing fetus. Radon is a naturally-occurring radioactive gas known to cause lung cancer. Aflatoxin is a naturally-occurring fungus that grows on peanuts and is among the most carcinogenic substances known, far more dangerous than the human-made pesticides, which worry so many people, that are used to control it.
But those are the scientific facts, and as I've noted in this space before, our perceptions of risk are based on not only the facts but also how those facts feel. Natural feels less scary that human-made. And that drives all sorts of choices that can be risky in and of themselves.
A recent Congressional study of herbal supplements found that almost all the supplements tested contained trace amounts of lead and mercury and other toxic heavy metals, and pesticides, and that the label on the box did not accurately reflect the ingredients inside. Can you imagine the uproar had that study been about pharmaceutical products from major manufacturers, Viagra or Prozac or Crestor? Yet there was hardy any public notice of the Congressional study, for the same reason there are few rules regulating herbal supplements and vitamins in the first place. They're natural, which means they're less scary, so we have not demanded scrutiny and control over them the way we have for human-made drugs. They're so lightly regulated, in fact, that when evidence starts to mount that an herbal supplement is causing harm, it takes almost as much science, and time, to get it off the market as it takes to get a pharmaceutical on.
The U.S. Senate is about to begin debate on an updated food safety bill that could remedy this problem, but it's unlikely much will be done to strengthen the FDA's power over herbal supplements. Listen carefully. Can you hear any loud, frightened voices demanding such additional protection? Of course not. There is no political demand to protect us from something we're not all that worried about...a risk that's natural...and as a direct result of this kind of affective perception, the millions of people who take herbal supplements and vitamins are at far greater risk.
