Three science mistakes that non-scientists make
post by Jen Coleman
I’m a sucker for science. I am inclined to believe it. So when politics and science get whipped into a froth and poured over a debate about protecting health and the environment, I need a refresher on what science can and cannot do.
Thanks, UC Berkley’s “Understanding Science” site, for the refresher!
http://undsci.berkeley.edu/teaching/misconceptions.php
Here are three things about science I learn and re-learn all the time:
Science mistake #1: Expecting to find the truth
When the news talks about “scientific proof,” it sure sounds like the truth is established. But a scientific idea is never once-and-for-all proven. There’s never certainty. Science works by collecting evidence, and then accepting or rejecting an idea until more evidence comes along.
When regulators in the U.S. say that a substance is “safe” for health, it sure sounds like they have proven it once and for all. But the system is rigged. In some cases, a substance is considered “safe” even when there are big gaps in our understanding of how it may impact human health. It takes far more scientific evidence before regulators will conclude that a substance is “unsafe”—often after people have been harmed.
Science mistake #2: Rejecting science because it is uncertain
Just because science can’t prove something beyond the shadow of a doubt, it doesn’t mean science is untrustworthy. Science at its best embraces uncertainty as a drive for exploration. Scientists test an idea in more and more ways, and come back with more and different kinds of evidence, making that idea more reliable and less likely to change.
So: who decides how much evidence is enough? Dr. Bruce Lanphear raises that question in his article on “The Impact of Toxins on the Developing Brain.” There’s a global system for deciding when there’s enough evidence to call something a carcinogen, but no such system for neurotoxic substances. Lead, mercury and PCBs are all “well established” as raising the risk of cognitive harm; but pesticides, air pollution and PBDE flame retardants are not considered “definitive” despite growing scientific evidence to strengthen such a conclusion.
Science mistake #3: Thinking science is a done deal
It happens all the time that scientists revise their accepted ideas—even those written down in textbooks. It’s not a mistake or an underhanded trick. It’s a healthy part of the process. We make decisions all the time based on the available scientific evidence, and it makes sense to do so. But if we’re smart, we’ll be able to respond when new scientific evidence requires us to make revisions.
For example, before 1950, we thought toxics could not pass through the placenta; then, new evidence showed that babies are exposed to toxics before birth. The heavy metal lead is also an interesting case: we once though there was a “threshold” so that, under a certain dose, lead had no effect on children’s brains. Now we have enough evidence to see that there is no safe level of exposure to lead.
The upshot:
Science is an important tool for decision-making. But we have to invest in science if we want it to work; “lack of evidence” is not a scientific way to make decisions.
That’s why OEC supports the Toxic Free Kids Act (SB 478): it would gather evidence we don’t have on how, when and in what quantities our kids are exposed to chemicals of concern in children’s products.
We also have to decide how much evidence we need in order to act; solid and irrefutable proof is not what science is about.
That’s why the Toxic Free Kids Act is focused on disclosing and replacing “chemicals of concern to children’s health.” There is enough evidence that these chemicals are in our environments and in bodies, and evidence that these chemicals can raise the risk of adverse health effects.
And then once we act, we must be prepared to both search for new evidence and, if warranted, make changes in our decisions based on that evidence.
That’s why the Toxic Free Kids Act asks the Oregon Health Authority to start paying attention to the new evidence showing that chemical exposures can raise the risk of some of our most prevalent and costly chronic diseases.
So, whether you’re a scientist, an English major or a business whiz, it’s good to keep perspective on the science we count on to keep our world going around. You can do something in the name of good science today: Tell your legislator to support the Toxic Free Kids Act.