Bisphenol A. Balancing Fact and Fear as We Face a Risk.

Have you heard about Bisphenol A? Maybe not. How about that potentially dangerous chemical that's been in the news, the one in plastic water bottles and baby bottles and in the lining of our food cans? That's Bisphenol A, BpA for short. It might be dangerous. It might not be. We don't know. But we DO know we're afraid. How are we supposed to deal with a risk like this, a mix of fear and fact?
Here's a quick rundown of the facts. BpA acts like estrogen in our bodies, turning up or down various systems influenced by that hormone. Some studies on rats and mice suggest that if a developing fetus is exposed to tiny tiny doses, at certain critical periods during fetal development, BpA can cause birth defects, particularly in a baby's reproductive organs. It may also impair fertility. There are a few small studies suggesting BpA may be associated with heart disease and diabetes in adults, but that evidence is pretty sketchy at this point.
Meanwhile, the U.S. FDA and European Food Safety Agency have analyzed hundreds of experiments that have been done on BpA to date, and they say there is no evidence the chemical is a risk to humans. It's safe, they say. No government has banned it, though the Canadians and some U.S. states have said, just as a precaution, it shouldn't be used to make baby bottles.
But boy does BpA hit some classic risk perception buttons. When we only have partial information like this, we tend to make judgments using something called the Representativeness Heuristic, the mental shortcut of making sense of what we do know by fitting it into categories of background knowledge that seem relevant. BpA is a CHEMICAL, and just because it's in that category it rings alarm bells. It's a product of the less-than-trusted chemical industry, another category that automatically triggers concern.
BpA is human-made, and that makes a risk scarier than if it's natural. (Soy is powerfully estrogenic too. Nobody's demanding that the FDA regulate that!) The risk of BpA, if there is one, is imposed on you via food containers. It's not something you choose, and an imposed risk always evokes more worry than if it's voluntary. BpA is undetectable by our senses, which makes it harder to do anything about, and the less control we feel we have about a risk, the more afraid we usually are. And the science of BpA is uncertain. The fewer facts we have about a risk, the scarier it usually is.
The same inherent psychological characteristics that tend to make BpA scarier to you and me, make it a better story to journalists, who want their work to get lots of attention. So news coverage of BpA emphasizes the uncertainty of the evidence, the questionable trustworthiness of industry-sponsored research, the fact that we're exposed to this human-made risk involuntarily via our food containers. The same psychological characteristics that make BpA alarming in the first case, are magnified in how the news media report the issue. And what the news media tell us about risks like this is pretty much the only way we know anything about it. So our fears grow.
Now the government has to decide what to do. Environmentalists say there's enough evidence to ban BpA. Industry says the evidence shows that it's safe. The decision that government faces about BpA is like most risks. It's not just a matter of the facts. It's how those facts feel. The TOXIC-ology and EPIDEMI-ology and BI-ology can only take us so far. In the end, policy will also reflect the PSYCH-ology of risk perception. In a democracy, that's as it should be.
The only problem is, that may produce policy that feels right, but doesn't maximize human and environmental health. If we rush to ban BpA, for example, will its replacements produce their own dangers? (We replaced carcinogenic solvents in the electronics industry with chlorofluorocarbons that turned out to destroy stratospheric ozone, which protects us from cancerous rays from the sun. D'Oh!) If we rush to ban BpA from containers of baby foods, can the infant formula industry convert to other ways besides cans to provide all the liquid formula moms need? Not without a lot of time to make that conversion (which some companies are working on already, foreseeing such a ban).
Facts, and feelings. Risk perception is a product of both. BpA is a great cautionary tale that we need to understand not only the facts, but the roots of our feelings, if we are to make the most careful and thoughtful choices about how to protect ourselves, as individuals, and as a society.

David Ropeik is author of "How Risky Is it, Really? Why Our Fears Don't Always Match the Facts" which explains our perceptions of BpA and many other risks.