body burden

I couldn't bring 9-month-old Connor with me when I attended my first POPs treaty meeting in Bonn, so I brought my breastmilk pump instead. I vividly remember struggling with my rusty German to convince the women in the conference center kitchen to store my milk in the deep freeze.

As a nursing mother, participating in the POPs treaty meetings took on a very personal dimension. Here's why: persistent chemicals build up in food chains across the globe, and this is a key reason the treaty exists. Human milk — nature's perfect food for infants — is at the very top of the food chain. This is why POPs show up so often in breastmilk.

Turns out a new generation of supposedly safer pesticides isn't so safe after all. In the latest entry of a growing body of evidence, scientists announced last week that pyrethroid pesticides — now in hundreds of pest control products sold for home use — can interfere with the healthy development of an infant's nervous system when moms are exposed during pregnancy. Here we go again.

History tells us that substituting one type of pesticide for another "safer" variety just doesn't work out very well.

Imagine if a persistent, toxic chemical was being added to all sorts of products you use everyday: soap, toothpaste, cosmetics, shaving cream, even toys and underwear. Imagine being told that it was put there to keep you safe from disease, when in reality it could end up making you sicker by contributing to antibiotic resistance. Imagine your food was being grown in fertilizer contaminated with this chemical, and that government tests found it in 75% of Americans. Finally, imagine you had an opportunity to do something about it.

Two studies came out in the last couple of weeks that really illustrate the problems associated with "PBT" chemicals: those which are simultaneously persistent, bioaccumulative, and toxic. Persistent substances resist degradation — you can move them around but it's really hard to get rid of them. Bioaccumulation happens when chemicals in food, water, and air end up getting stored in the body of a living thing. Thus, for a bass living in a mercury polluted lake, the mercury levels in the fish may be thousands of times higher than the levels in the water. A cow grazing on PCB-laced feed will store the chemical in her body and excrete it in her milk, and humans too act as sinks for all kinds of chemicals.

Last week, researchers found a host of toxic chemicals in the bodies of pregnant women throughout the U.S. Industry reps quickly trotted out their favorite messages in response: "Chemicals are a fact of modern life," "just because toxins are in your body doesn't mean they'll hurt you," and "the levels are too low to matter - researchers have new tools that can measure extremely low levels." 

The fact is, low levels of chemicals in the womb can matter a whole lot. And studies like last week's make the chemical industry very, very nervous.