Chemicals producing carcinogenic effects

'10 Americans' hits home for Mill Valley mom
Jessica Werner Zack, Special to The Chronicle

Monday, March 16, 2009

PCBs. VOCs. Pthalates. Bisphenol A (BPA). The list of industrial chemicals on the minds of consumers is crowded with confusing new acronyms as growing scientific data show a link between chemical exposure and a range of behavioral, reproductive and immunological problems.

Marie McGlashan, an acupuncturist and health-conscious Mill Valley mother of three, says she "stays up on the health issues surrounding pesticides and chemicals, especially when it comes to what to feed my family." So when she joined a group of parents at San Francisco's Katherine Delmar Burke School last fall to hear environmental advocate Ken Cook speak, she didn't expect to be "so stunned by the findings I heard. Seeing his '10 Americans' presentation was a dramatic moment for me."

Cook is the energetic and persuasive co-founder of Environmental Working Group (EWG) in Washington, D.C., a research organization and public health lobbying powerhouse. Cook has been traveling the country since 2005 presenting the findings of EWG's "10 Americans" study, which tested the umbilical cord blood of 10 babies born in U.S. hospitals from a random sample supplied by the Red Cross on the same day in 2004.

287 chemicals found
The research was the most comprehensive testing ever conducted on human umbilical cord blood. It found 287 industrial chemicals in the samples, nearly half of which are known carcinogens. Also detected were dozens of widely used brominated flame retardants (PBDEs) and their toxic by-products, and numerous pesticides, including DDT and others, which were banned more than 30 years ago.


"The placenta does not filter out toxins to the degree scientists and doctors once believed," said Cook by phone from Washington, D.C. In reality, a baby in utero "lives in a critical window of vulnerability," according to Cook, with an immature blood-brain barrier that efficiently transfers nutrients - as well as contaminants - to his or her internal organs.

"I'm not suggesting for one minute that just because you have a carcinogenic chemical in you it's going to cause cancer, or even that if you went out and got tested for a chemical that would necessarily tell you what you should then do for your health," Cook says. "But what we do know about the overlap between genetics and environment is profound.

"We're no longer talking about nature versus nurture. We simply don't mutate and evolve quickly enough to explain things like a 40 percent increase in childhood brain cancer, soaring autism and infertility rates or one in seven women getting breast cancer. One scientist I know says, 'Genetics loads the gun and environment pulls the trigger.' "

Simple lifestyle changes
He promotes making simple lifestyle changes that can minimize chemical exposures: Use cast-iron pans instead of nonstick; filter your water for cooking and drinking; buy organic; avoid products with added fragrance (which is often an indicator of pthalates).

And most of all, he urges people to "realize how much positive change we're capable of. We got lead out of gasoline, we banned PCBs, we got rid of DDT - and we still have cars, we still have an electrical grid and we still have food to eat. Now we need one additional step regarding chemicals and it's pretty simple: If they're in people, we ought to be damn sure they're safe."

Jessica Werner Zack is a freelance writer in Marin. E-mail us at datebookletters@sfchronicle.com.

This article appeared on page E - 6 of the San Francisco Chronicle