Environmental Contaminants: What’s in Your Blood?
by Bill Chameides | April 7th, 2010
posted by Erica Rowell (Editor)
How many toxins are in our bodies? How much do we know about them? And what should be done about stemming their flow? Those were some of the ideas in last night’s lecture at Duke by Environmental Working Group president Ken Cook.
Yesterday Duke celebrated another NCAA championship, but for me the day’s highlight was a lecture about environmental contaminants.
Ken Cook, co-founder and president of the Environmental Working Group (EWG), a non-profit organization dedicated to using “the power of public information to protect public health and the environment,” was on campus yesterday. His lecture, entitled “10 Americans,” stunned the Duke and Raleigh-Durham folks in attendance.
Cook’s Journey to Environmental Advocacy
After the talk, Ken told me he knew early on he wanted to work in environmental policy. The circuitous route he took began with a bachelor’s degree in history followed by a master’s in soil science. It was as an analyst in the Library of Congress that he first learned about agriculture policy, thus launching one of his life-long crusades — reform of the U.S. farm bill.
His stint at the World Wildlife Fund was punctuated by time off to work on, in his words, the blankety-blank Dukakis campaign: “How,” he asked, “could a campaign blow a 20-point lead?”
In 1993 Ken co-founded the Environmental Working Group. Not surprising, reforming our agricultural policy is a main focus of EWG. Another is tightening regulations on environmental contaminants to protect human health. And that was the topic of Ken’s talk.
Ken began with the story of an EWG study of American blood. In 2004, blood samples from ten Americans were shipped off to a lab and tested for the presence of 413 known toxic compounds. The results? Traces of 287 toxic compounds were found, including:
- 28 waste byproducts like dioxin,
- 47 consumer products such as flame retardants, and
- 212 industrial chemicals and pesticides.
Incredibly, many of these compounds had long been banned for use in the United States because of their dangerous environmental and health effects. These included PCBs (see my video) and breakdown products of DDT — both banned more than 30 years ago.
So where did these blood contaminants come from?
Ken assured us the individuals tested didn’t get them from air pollution, drinking water, consumer products, or occupational exposure — a mystifying pronouncement until he revealed a picture. The sonogram of a baby in its mother’s womb provided the “aha” moment — the 10 Americans were newborns, the blood samples had come from their umbilical cords, and the source of each baby’s toxic contamination was the mother. Clearly, the placenta, which prevents a mother’s blood from mixing with the fetus’s, does not prevent toxic chemicals from flowing from mother to child. In short, these babies were born “pre-polluted” at the earliest stages in their development.
Low Doses and Health Effects
The chemicals found in the newborns included known carcinogens, endocrine disrupters, and neurotoxins. But, Ken pointed out, the findings don’t necessarily mean that these chemicals pose health risks. By the same token, we also don’t know that they don’t. As Ken put it, “If we’re finding a chemical in newborns, oughtn’t we know that the exposure is safe?”
Some argue we needn’t worry about finding contaminants in a fetus because their concentrations in the blood are so low — as little as one part per billion (ppb). In short the argument goes: Low doses don’t matter.
But how is low defined? Is one part per billion really too low to matter? To answer such questions, Ken presented blood-level data on some therapeutic dosages of several popular drugs:
|Drug||Use||Blood Concentration of Dosage (ppb)|
Then he posed some questions I consider worth pondering:
- If these drugs are capable of having significant physiological and neurological effects on humans at low doses, why would we assume that toxic chemicals at equivalent levels in our bloodstream would be benign?
- Before these drugs can be sold, companies are required to go through extensive tests, at great expense, to prove they’re safe. Why wouldn’t we insist on the same level of safety for the chemicals in our bodies that we unwittingly pass on to our children?
The Way Forward
So what’s a consumer and/or mother to do? To start, Ken suggests becoming a “smart shopper.” Know what you buy, what you eat, and what you wear. Even then, he warned, environmental contamination by industrial pollutants and toxic chemicals in consumer products are so ubiquitous it’s virtually impossible to avoid them. (For example, try furnishing your home sans toxic flame retardants.)
The real solution in Ken’s opinion lies with Congress — and a more effective law controlling toxic substances, one with real teeth. The current Toxic Substances Control Act requires the Environmental Protection Agency to prove a chemical is dangerous before it can be banned, but the bar for proof is so high that only five out of an estimated 80,000 plus available chemicals have been banned or restricted (read my related post). The new bill, Ken argues, should turn the tables and require that companies prove the safety of chemicals before they’re let loose in the marketplace.
The argument against such reform is that it would burden industry and raise prices for consumers. I guess it comes down to which you care more about: What’s in your wallet or what’s in your blood.filed under: faculty, health, toxins
and: consumers, contamination, Environmental Working Group, Ken Cook