Living Well: Huge CDC report on toxins shows need for further study

By BOB CONDOR
SPECIAL TO THE POST-INTELLIGENCER

A quick chemistry lesson: There are about 80,000 chemicals registered for U.S. industrial use. Some 3,000 of them are produced at rates of 1 million pounds or more.

That's a long list. You would have to consider it impossible for the government to monitor all 80,000 or even the heavy-duty 3,000 for public health safety. It's just too much for the likes of the Environmental Protection Agency or Centers for Disease Control and Prevention.

The logical approach is to turn it around. Require companies to prove chemicals used in their products won't harm people. Put the burden of proof on marketers ready to sell the newest cleaners or bug killers or fire-resistant electronics equipment.

That idea, though entirely sound, doesn't stand a chance of enduring highly politicized corporate America. Can you say "lobbyist?"

So the next best thing is to test people. See what chemicals show up in their blood and urine. If public health officials and environmental activists can get enough people to notice that adults and kids alike are walking chemistry labs, then maybe some sort of pressure can be applied to companies using potentially harmful chemicals in their products.

"Instead of rubber-stamping almost every new chemical that industry invents, we've got to strengthen and modernize the laws that are supposed to protect Americans from pollutants," said Jane Houlihan, vice president of research for the Washington, D.C.-based Environmental Working Group ( www.ewg.org ).

To that end, Houlihan and plenty of her eco-minded colleagues were glad to see the federal government itself get a bit deeper into the activism end of protecting us from toxic chemicals. Last Thursday, the CDC published its Third National Report on Human Exposure to Environmental Chemicals.

The findings were not unexpected but nonetheless dramatic. The CDC reported most of us have dozens of pesticides and other toxic compounds in our bodies. One common chemical is the family of pyrethroids, which are active ingredients in pretty much every household pesticide. There are a high number of Americans with an overload of phthalates used in nail polish, other beauty products and soft plastics.

It is the first time researchers have investigated pyrethroid levels in the body. The synthetic is a common ingredient in both household pesticides and mosquito sprays. Considered safer than older pesticides, including DDT, pyrethroids can be toxic to the nervous system in high doses. Some scientists think lower doses can still adversely affect hormonal function.

The CDC report is expansive -- more than 400 pages explaining a study that searched for 148 toxic compounds in 2,400 Americans 5 years or older.

"It is the largest and most comprehensive report of its kind ever released anywhere by anyone," CDC director Julie Gerberding said during a news conference.

But the CDC report is still limited in scope, mostly because it documents the chemical load in our bodies yet doesn't get into the business of interpreting how those toxic compounds will affect our health.

"It is an essential initiative and the first time we have known the extent to what we carry in our bodies," said Elise Miller, director of the Institute for Children's Environmental Health based in Freeland. "But there are lots of missing pieces, such as gene-environment interaction and synergistic exposure. We are still studying one chemical at a time."

Miller said researchers and non-profit organizations will be at the forefront of determining which chemicals are the biggest disrupters of good health. Her organization will spend the next month preparing an analysis to "translate the CDC data for lay audience."

"The CDC findings are still a lot less than we need to know," she said.

The Environmental Working Group is well respected for its "biomonitoring" studies. Just this month, EWG released a study showing the presence of more than 200 chemicals in umbilical cord blood. The sample size was relatively small at 10 but every cord specimen (donated by the Red Cross from 2004 births) was loaded with nearly 300 chemicals, including many known to be toxic or cancer-causing agents such as mercury, fire retardants, pesticides and the Teflon chemical PFOA. More than 200 of the potentially toxic compounds were never before discovered in cord blood. The study is available at www.ewg.org/reports/bodyburden2

What concerns scientists is that until now it has been assumed that the placenta protects an unborn baby from toxic exposure. This study indicates otherwise.

"Chemical exposures during childhood can be far more harmful than those later in life," said Houlihan of EWG. "Our cord blood findings above all raise the need for more testing. The companies that produce these chemicals have a responsibility to know if their products end up in babies, and to share what they learn with the public."

Unfortunately, those companies aren't willingly sharing information about potential harm or even how to tell if someone has high exposure to one of their chemicals. It is critical that public awareness moves to outcry and demand for change.

While it is to be commended for putting time and money into chemical exposure in humans, the CDC knows an opportunity to play up the positive. It cranked out press releases and the news conference statements made sure to point out that both lead exposure in kids (mostly because it was eliminated from gasoline and paint) and secondhand smoke exposure are dramatically lower than past periods.

Miller was neither fooled nor cynical.

"Lead and secondhand smoke are key pieces," said Miller, adding that she would like to the see the government look harder at flame retardants in its next report on human exposure to environmental chemicals. "In fact, they are wonderful examples of when public health policies are successful. We simply need more regulation and public health policy on other toxic compounds."