Chemicals are one of the wonders of creation. They help heal and feed us; they help fuel our autos and heat our homes; they help produce toys and computers. Yet some chemicals can hurt, making them a perfect target for alarmist demagogues.
According to the Centers for Disease Control's latest "National Report on Human Exposure to Environmental Chemicals," most people had contact with many of the 116 chemicals it studied. Yet this conclusion reflects dramatic advances in biomonitoring.
Scientists are now capable of detecting the minutest trace of a substance, measuring concentrations of millionth and billionth parts.
This enables us to better assess chemical exposure and risk. But it also enables extremists to ignore contact levels when claiming an epidemic of chemical exposure. In fact, the CDC found much good news. Exposure to lead, which is particularly harmful to children, and cotinine, a tobacco residue, is down.
Contact levels with some of the most toxic chemicals were extraordinarily low. Reported the CDC: "For dioxin, furans and coplanar PCBs, most people in the Second Report had levels that were below what the analytic method could detect."
Even the bad news was bad mainly relative to overall successes. For instance, during the 1990s cotinine exposure dropped 55% for teens, 58% for kids, and 75% for adults, yet the levels facing black children remain disproportionately high.
Alas, good news never deters environmental extremists. The Environmental Working Group conducted its own study and found an average of "91 industrial compounds, pollutants, and other chemicals" in nine volunteers studied.
Many of these chemicals, claimed the group, cause cancer, birth defects or other harms. The result is a significant "body burden," as the group puts it.
Scientifically Uninformed
But this is fear mongering at its worst. Simple exposure demonstrates nothing. As the CDC explained: "Just because people have an environmental chemical in their blood or urine does not mean that the chemical causes disease."
This is the case even with substances known to be capable of causing harm. Observes Elizabeth Whelan, president of the American Council on Science and Health, people "should remember the basic tenet of toxicology-the dose makes the poison." Almost anything may be harmful if ingested in concentrations vastly above the levels faced by normal people.
Animal tests also often fall afoul of the substantial differences between rodents and primates. In many cases absorption rates, which vary among creatures, matter far more than exposure levels.
Argues Todd Seavey of the council, "thanks to the CDC report, we're now more certain than ever that the synthetic chemical amounts we are routinely subjected to are trivial. We ought to feel safer than ever."
The Collaborative on Health and the Environment, an umbrella group for the alarmists, claims that chemicals are currently hurting one-third of the population.
This is an attractive argument for the scientifically uninformed, but it fails the basic test of evidence. As Steven Milloy, publisher of Junkscience.com, points out: "Despite more than 40 years and countless billions of dollars of research, no credible scientific evidence exists to link typical exposures to chemicals in the environment with disease."
Indeed, though our theoretical exposure to chemicals has increased dramatically over the last half century, actual chemical contamination of the environment has been falling. And we are living longer and healthier lives than ever. Apparently the human body is well able to bear the alleged chemical burden.
Americans have much to be thankful for, including chemicals. Of course, as with all human phenomena, chemicals generate costs as well as benefits. But we are well-equipped to deal with the many challenges of modern life.
