Regulation begins with risk assessment—a careful weighing of the risks and benefits associated with any given chemical. In an ideal world, unbiased, professional regulators would assess the safety of every new chemical before it entered our lives. They would discern all the potential consequences of excessive or continued long-term exposure and, in so doing, would protect us from any slow, unwitting poisoning. In reality, of course, a variety of factors—practicality, economic forces, sheer need— makes implementing such thorough precautions nearly impossible.
The process of weighing the risks and benefits of a particular action in order to decide how to proceed.
Federal agencies (namely the Food and Drug Administration [FDA] and EPA) are mandated to protect us from harmful chemicals; they have the authority to heavily regulate or ban outright chemicals deemed to be dangerous. For substances where the data are uncertain and where the substances may cause unexpected or unpredictable effects, these agencies can employ a “better safe than sorry” strategy known as the precautionary principle. This rule of thumb calls for leaving a wide safety margin when setting the exposure limit—the maximum quantity humans can safely be exposed to. The width of that margin depends on the severity of the potential health effects and environmental damage.
A principle that encourages acting in a way that leaves a margin of safety when there is a potential for serious harm but uncertainty about the form or magnitude of that harm.
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Risk assessment helps us determine the best way to deal with dangerous chemicals. If there are uncertainties, we can apply the precautionary principle and leave a wider margin of safety when setting exposure limits.
The precautionary principle is becoming a favored tactic in the European Union. But in the United States, for the vast majority of chemicals, we take a different approach: “innocent until proven guilty.” Rather than thoroughly testing each individual compound, regulators make educated guesses about safety, based on how other, similar compounds have fared. As a result, toxic products are often discovered only after (sometimes long after) reaching the marketplace—usually when some person or group of people suffer the effects. Rather than preventing these products from reaching store shelves in the first place, we recall them after the fact. This ad hoc regulation puts on the public the burden of proving that a chemical is actually more dangerous than expected.
As the case of BPA shows, even when concerns about safety emerge, deciding which precautions to take can seem like an impossible task. Part of the problem is that, even in our era of warp-speed communication, information is a slippery thing; this is especially true when it comes to science. We are constantly uncovering new information and gleaning new insights about the environment and our relationship to it. And as our understanding grows and changes, existing information often becomes obsolete. In fact, much of what we learn in science class today will be outdated 5 years from now—not because we are wholly ignorant in the present but because we will know so much more in the future.
In fact, much of what we learn in science class today will be outdated 5 years from now—not because we are wholly ignorant in the present but because we will know so much more in the future.
In this rapidly moving current of knowledge floats a seemingly endless array of information sources: newspapers and magazines, websites, scientific journals, and so on. Not all of these sources are equal. While some are carefully vetted for accuracy, others are incomplete or deliberately misleading.