Chapter Introduction
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CHAPTER 3
INFORMATION LITERACY AND TOXICOLOGY
TOXIC BOTTLES?
On the trail of chemicals in our everyday lives
CORE MESSAGE
Our understanding of the natural world changes almost daily as new evidence is gathered. Unfortunately, misinformation about science abounds in the popular press and on the Internet. For example, we live in an environment full of natural and synthetic chemicals, some of which are toxic, but knowing how to respond to the latest toxic scare is often difficult as we receive conflicting messages about the safety or risks of various chemicals. Developing information literacy skills enables us to better evaluate the usefulness and trustworthiness of various sources of information and then use the highest-quality information we can find to make reasoned decisions about how to respond.
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AFTER READING THIS CHAPTER, YOU SHOULD BE ABLE TO ANSWER THE FOLLOWING GUIDING QUESTIONS
1 What are toxic substances, and how do we make decisions regarding the risks of exposure to these chemicals? Why is the solubility of a toxic substance important to individuals and to ecosystems?
2 What is information literacy, and why is it important?
3 What factors influence a chemical’s toxicity? How is toxicity determined?
4 What are endocrine disruptors, and why is it often harder to determine a “safe dose” of them than it is to determine safe doses of other types of toxic substances?
5 How can we use critical thinking skills to logically evaluate the quality of information and its source? What common logical fallacies are used in presenting arguments?
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In 2008, after a decade of study and contentious debate, a U.S. government-appointed panel of scientists known as the National Toxicology Program (NTP) finally arrived at a tentative consensus: Based upon data they had accumulated up to that point, they wrote in a report that would splash across headlines, they had “some concern for effects on the brain, behavior, and prostate gland in fetuses, infants, and children at current human exposures to bisphenol A.”
Bisphenol A, or BPA, as it is more commonly known, is a synthetic chemical. Since the late 1940s, it has been a staple ingredient in the linings of metal food cans and plastic products of every kind, including food and beverage containers and plastic baby bottles. But in the two preceding decades, a mountain of scientific studies had implicated the unassuming compound in a rash of serious medical conditions, from impaired neurological and sexual development to cancer. At that time, both Canada and the European Union were considering banning the use of BPA in baby bottles and baby formula cans. Most of the NTP panel’s scientists felt that the data were still too uncertain to warrant such a drastic step. But, they thought, it would be prudent for industries that used the chemical to start looking for a replacement. “The panel raised important research questions and public health concerns,” says Sarah Vogel, a public health historian with the Johnson Family Foundation who has closely tracked the case of BPA. “For the first time ever, the U.S. government was suggesting that BPA might not be safe.” The report incited a frenzy.
KEY CONCEPT 3.1
The environment is full of natural and synthetic toxic substances that have the potential to harm living things, and most of them have not been tested to determine safe exposures.
The plastic industry decried the report’s conclusions. In a firestorm of press releases, in newspapers across the country and on cable news, industry spokespeople insisted that their own data showed BPA to be perfectly safe.
Parents everywhere were torn. On the one hand, it was hard to believe that something as commonplace as BPA could be so dangerous; if at least some studies were showing it to be safe, maybe it was. On the other hand, if there was even a chance that this chemical could harm their children, shouldn’t the government take every possible precaution? BPA-free products were exceedingly difficult to find, and without some sort of federal mandate, that was unlikely to change. What were average consumers to do?