This study features the largest number of chemicals ever tested for in the same group of people – 210 chemicals were tested. The results were staggering – each participant tested positive for an average of 53 known human carcinogens, 55 chemicals known to cause birth defects or developmental delays, and a host of other chemicals. Each participant tested positive for chemicals that damage the brain or nervous system, that weaken the immune system, and chemicals that cause reproductive abnormalities. Perhaps most disturbing: these 210 chemicals tested represent only a small fraction of people’s exposure. More than 500 chemicals are used in the U.S. as active ingredients in pesticides alone. More than 3,200 chemicals are regularly added to foods. More than 2000 new chemicals are registered for use in the U.S. each year – most with no safety testing.
Combinations of chemicals can be far more damaging than individual exposures. We do know that just as drug-drug interactions can cause serious side effects, chemical-chemical interactions can multiply the risks. For example:
This Body Burden Report shows PCBs and dioxin in the same people. These often appear together – even in breast milk. Researchers looked at liver damage caused by the two. By themselves, the PCBs caused no liver damage. Dioxin did cause some. But mixed together, the two chemicals produced 400 times the damage of the dioxin alone. (Van Birgelen, A.P.J.M., et al. Environmental Health Perspectives (1996) 104:550-557.)
Some pesticides in common use can act like the female sex hormone estrogen. Researchers at Tufts University School of Medicine measured the effects of 10 such pesticides. Taken one at a time, they had no measurable effect on human tissue. But when different combinations were tested, these same low levels of pesticides now showed a strong estrogen effect. (Soto, A. et al. Environmental Health Perspectives (1994) 102: 380-383.)
Two commonly used pesticides, aldicarb and atrazine, are found in our food and our drinking water – and in our bodies. When tested individually at levels found in the groundwater in the U.S., they showed no adverse effects. But when combined – the way they are in the water – the combination produced immune system impairment. (Porter, W.P., et al. Toxicology and Industrial Health (1999) 15: 133-150.)
In short, the Body Burden study reminds me of a smoke detector or a carbon monoxide alarm – alerting us to a silent but serious danger, hopefully in time to wake us from our sleep. This study leaves no doubt about the pervasive pollution of our bodies with large numbers of toxic chemicals in combination, most of which didn’t even exist when my parents were born.
Major Recent Studies