We see the same thing with individual kinds of chemical exposures as well. One of our NIEHS grantees, Philippe Grandjean of Harvard University, followed women during their pregnancy, and then he followed their children. So he had blood samples before they were born from the mother. He had blood samples at birth, and he continued to follow the kids. What he found is that if those children had elevated exposure to PCBs [polychlorinated biphenyls used in electronics], they were less able to mount a normal response to a vaccination.
PCBs are considered likely carcinogens, but they are also endocrine disruptors, like bisphenol A or dioxin, which is something we've heard a lot about in the media lately. What is your definition of an endocrine disruptor?
An endocrine disruptor is anything that affects the synthesis of a hormone, the breakdown of a hormone or how the hormone functions. We used to think it had to bind with a hormone receptor but endocrine disruptors can perturb hormone action at other stages in the process.
Why are they such a big deal?
They're all around us, and I think they can affect us at very low levels. Our hormones control our basic homeostasis, our basic physiology. If you alter your hormone levels, you're not going to behave the same way physiologically, and that includes mentally and everything else. I think that there's growing evidence that some of the chemicals to which we are exposed are doing that to the population right now.
So we have this soup of endocrine disruptors, air pollution and other exposures, which has made epidemiology so difficult. What have you been doing at NIEHS to get to the bottom of these issues?
There are ways statistically that you can control for some of these factors, but I think we have to go beyond that and say, "Well, wait a minute. That's not real life." Maybe we need to look at whether there are interactions. In animal systems, from work that I did starting in the '80s and have continued ever since, we showed that for chemicals that have the same mechanism of action you can basically add up those chemicals to predict the toxicity. This is the toxic equivalency factor approach.
We've been finding with a lot of endocrine disruptors that if they impact the same health effect, such as decreased sperm production, you can just kind of add up chemicals. They may have a different mechanism, but they all affect sperm count. A lot of data show that if chemicals are estrogenic, you can add up their potency. If chemicals are anti-androgenic, you can add them up. If chemicals affect thyroid, you can add them up, too.
Nobody has tried to look even more broadly and say, "Well, I'm gonna take all these chemicals that somehow block male reproduction, and I'm also gonna add that to the chemicals that do something totally different." The way I think we're going to have to eventually get at that is through what we're calling "Tox21," which is this rapid-screening approach being developed with high-throughput screening of in vitro assays. They are cell-based assays looking at many, many, many different kinds of responses. Basically, we can screen up to 10,000 chemicals a year at 15 different dose levels for at least 70 or more different kinds of responses. We can begin now to do this with mixtures where we can make many different kinds of mixtures because we can test so many at a time.
How has spending 33 years studying toxic chemicals affected your outlook on the environment?
We do know that there are many chronic health conditions, non-communicable health conditions, which have increased too rapidly in the last 20 to 40 years. These are things like autism, ADHD and, of course, obesity and diabetes. We have identified chemicals clearly at play in the obesity epidemic. I am not in any way saying to people you can stop exercising and you don't have to watch what you eat, but the question I have is: Are we setting people up to fail because they're exposed to something that alters their ability to metabolize fats or sugars?
Overall, I'd say I'm a pragmatist. I think our air in this country is cleaner than it was, but it's not as clean as it needs to be. Our water is cleaner, but again not as clean as it needs to be. We've taken care of the really blatant environmental problems. We're concerned now about low levels of lead, not the very high levels that there used to be in our environment.—That's a good thing.
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Add CommentFrom using coal ash in kitchen products to polluting ground water to insufficiently or untested food additives to home pesticides, humans have always and will always be the guinea pigs. We can’t really trust the FDA or NIH when it comes to pharmaceuticals; not even OTC meds. The US chemical industry is so politically powerful and so entangled with modern life that the public is basically screwed. So, if we are going to be exposed to something like hexavalent chromium or coal ash no matter what, why even bother with a healthy diet or exercise. If the government doesn’t really care enough about the public to ensure the health of the nation why even bother with the pretense?
Reply | Report Abuse | Link to thisScience finally recognizes that we are a chemical soup composed of water and carbon living in a bigger chemical soup of environment composed of other elements, and life is sustained by various chemical bondings between these two soups.
Reply | Report Abuse | Link to thisI think its more to do with business acting with impunity. It seems obvious the people working for
Reply | Report Abuse | Link to thisthe agency are very concerned. All the agency can
accomplish is to make known the dangers. It really
is up to ALL of us to be informed.
There is a point where the 'other' is actually us.
A surprisingly uncritical and one-sided article, not up to SA's usual journalistic standards.
Reply | Report Abuse | Link to thisWhile much is made of the influence of business interests on US regulatory policy, we don't hear very often about the inluence of activists, which is equally pervasive and, in my experience, significantly more prone to distortions and half-truths. We also too often uncritically conflate the interests of activists with those of the public; while there may be overlap, these are not the same. Finally, we often assume that because someone is employed by a federal agency that they don't have an agenda, but this is in too many cases not correct. Unfortunately, when one becomes an activist (regardless of their agenda or academic and professional qualifications), they cease being a scientist.
If you have read 'Silent Spring' then you know how
Reply | Report Abuse | Link to thisnegligent business can be. Then there is 'Love Canal'.
The Gulf multiple oil spills.
Though the people's reaction might seem overly restrictive, they have very good reason to hold
that view.
Another for the Cassandra file.
Reply | Report Abuse | Link to this"No one except possibly the late John Brunner, in his brilliant novel "The Sheep Look Up," has ever described anything in science fiction that is remotely like the reality ... as we know it."
-- William Gibson in a 2007 interview
http://en.wikipedia.org/wiki/The_Sheep_Look_Up
Unfortunately, you've avoided responding to my point. I don't think anyone would argue that business has not on some past occasions been irresponsible, and at other times the hazard created by an action simply wasn't recognized until later.
Reply | Report Abuse | Link to thisMy point is that while business has an agenda, activist groups have one also, which is chiefly to raise funds for their continued existence; this often means distorting evidence or trumpeting conclusions that are unsupported by the data. Assuming that someone who is an activist has pure motives is as great a mistake as assuming the same of business. Again, once you allow activism (of any stripe) to color science, it is no longer really science.
We all want clean food, air and water. Don't we? If we do, then respective groups in society have a responsibility, as human beings, to safeguard these things. Businesses, individuals, trade organizations, governments. Science is a great tool, but it is only that. True science keeps asking questions, simply because of the complexity of the world around us. Therefore, science ALONE will never give society the answers. The answers will be found in the CONscience necessary to care about Earth's beings and environments, in light of what is known.
Reply | Report Abuse | Link to thisExplain "Chemtrails", the who, what, how, when, and why, and effects of GM frankenfoods as well as on humans directly.
Reply | Report Abuse | Link to thisI agree.
Reply | Report Abuse | Link to thisWhew. After reading this article, I feel like I'm swimming in "chemical soup." LOL. =)
Reply | Report Abuse | Link to thisI totally believe all the chemicals and plastics are causing all these illnesses that we have. There are tons of people now with autoimmune illness now and cancer is rampant. We should take a look at the Amish, they don't use chemicals and most of them are really healthy.
Reply | Report Abuse | Link to thisThe EPA did a huge job protecting citizens from contact with chemicals but were more effective protecting individuals from grams of useful chemicals and net, net let the tons users be in charge of learning. We now have a generation that will pour out rubbing alcohol after 2 years on their own shelf without the thought that nothing changes without chemistry. Without thought is the result of no contact by generalized fear and ignorance.
Reply | Report Abuse | Link to thisIf you read "The True State of the Planet"
Reply | Report Abuse | Link to thishttp://amzn.to/IrVHYa
you might have a different opinion! No one died or contracted cancer at Love Canal, and DDT is much
safer than Rachel Carson described.
Ditto!
Reply | Report Abuse | Link to thisIsn't odd how any time someone doesn't support the chemical industry they are "activists" and their science is somehow suspect? Not that there is anything wrong with being an activist, or, more to the point, that activists can't be good scientists. To say that this article is "not up to the usual standards of SA" is ridiculous on the face of it. It is an interview with a scientist who is respected internationally with good reason for her 33 years of outstanding science and contributions to the field. If you knew remotely what you were talking about, you would know that when Dr. Birnbaum began the dioxin review - now over 20 years, delayed continuously by the chemicals industry - she thought the review would show what the industry said it would show - that the dangers of dioxin were exaggerated. To her own surprise, the findings of the rigorous scientific analysis of the reassessment changed her mind. The data changed her mind. The truth emerges from the data, not someone's political agenda, or commercial interests. Efforts to malign Dr. Birnbaum - or Scientific American, for that matter, for publishing this article - are the true reflection of bias and activism. Why aren't the efforts of those who stand in the way of chemical reform, who reject all but their own "science", and who have their own political agenda also considered activists, and why don't they identify themselves as such? Those who deny the reality of what the science - solid, reproducible, reputable, peer-reviewed science - has shown are no different than those who deny that human activity has an impact on global climate effects. They are the same people who denied the links between tobacco and cancer, and they use many of the same tactics. SA should be applauded for articles that educate about these issues,and the comments about "Cassandras", the quotes from William Gibson who wrote science fiction himself, and the continued bashing of Rachel Carson are frankly laughable.
Reply | Report Abuse | Link to this