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Contamination
threatens Thank you for inviting me today to address such an extraordinary group of community activists from around the country. Let me begin with a story. I was in far western China a few weeks ago, at the edge of the Tibetan plateau. I was there to look at some work the W. Alton Jones Foundation has begun supporting to develop new sources of energy for rural communities. We hope to free mothers from the need to use kitchen fuels like coal and firewood that often lead to blindness after long-term indoor use. We had hiked into a remote village, 6 hours over a trail that climbed over a 14,000' pass. No roads led into this village. The scenery was magnificent. Picture it. 22,000' jagged peaks in the background, covered with snow and ice. The village nestled in a U-shaped valley cut by ancient glaciers. Beautiful forests along the hillsides and a grassy meadow in the bottomland.
What a scene. Mountains. Forests. Valley. Yaks clanging. And in the foreground a purple monk. He stood stock still, it seemed, for 20 minutes, his hands raised together in front of his chest, thumbs on top, elbows by his side. He was staring fiercely at his thumbs. A tea kettle hung from his left elbow. As I walked closer I could see that his thumbs were moving slightly up and down, as if he were working prayer beads. Finally I got close enough to see what he was holding so intently. A Game Boy. The world is changing very fast, and all is not what it seems at first glance. From rural China I went to Denmark. In far western China I had been a giant. In Denmark I was a midget, surrounded by large, virile men and tall, lithe women. I was in Copenhagen for a scientific meeting during which I learned something quite unexpected about those virile men. They were not all they seemed.
This is within a range at which fertility impairments are expected. As a biologist, I can tell you that even if we don't know all the details of what is happening, even if there is some uncertainty and imprecision, a population composed of men of whom 40% have biologically-based fertility impairments is not a normal population. These data are consistent with reports from other countries indicating that over the past 50 years some places in the world have experienced large declines in sperm count. And fertility patterns are changing in women, also. For example, before 1921, there had been only 20 cases of endometriosis reported in the medical literature. Endometriosis can dramatically reduce a woman's ability to bear children. Now we know that at least 5.5 million women in the US and Canada are affected. It is appearing with ever greater frequency in younger women. Endometriosis can be a difficult condition to detect. Some of the increase, perhaps a lot of this increase, has been due to increasing efficiencies of detection. But not all. Public health experts believe that the real rate of endometriosis has increased substantially since World War II. These are two scientific hints of a future in which men and women who wish to have children but can't will become increasingly common. They are hints that a new front will open up in the global fight over reproductive rights. The right to choose is the right to make your own choices about when to have children. Here to fore, it has been assumed, for the most part, that when you want to, you can. I believe this assumption is no longer a safe one, for an increasing number of people in the world. There are likely to be multiple causes for this. Some have to do with life style choices, simple biologically realities that flow from the choice many women are making in this country to wait until later in life to conceive. But this is not the whole picture, as suggested by the high frequency of fertility impairments in young Danish men and increasing commonness of endometriosis in younger women. The scientific meeting I attended in Denmark was about a new field in biology and toxicology that has emerged during the last 10 years. It has grown out of a series of disparate discoveries indicating that widespread contamination can interfere not only with the ability to reproduce, but also with the quality of life that might be expected for a child that grows to maturity after exposure in the womb. Not just their experience as a child, but life-long impacts on intelligence, disease resistence and fertility. I should state at the outset, and will remind you as several points through my comments that the science on this issues is incomplete. In an absolute, pure scientific sense, there is not certainty, but in my opinion and in the opinion—and indeed in the opinion of the Royal Society, Britain's equivalent to our National Academy of Sciences in a report issued last month—enough is known to recommend that strong measures be taken now to reduce exposures. So what's the story? There are four pieces to the story. First, we are all contaminated, every person in this room, by several hundred compounds that were not part of human body chemistry just 3 generations ago. Some of those contaminants are most likely benign, some are known to be harmful, but for the vast majority, we don't know. The two generations of people born since world war two are walking, global experiments in toxicology. Second, we have learned through research with animals that some of these compounds intefere with the hormonal signals that guide development in the womb. The developing embryo and fetus depends upon getting the right natural hormonal signals at the right time in development. They determine what that individual will become-things as basic as sex, the number of digits, the shape of the uterus if it is a girl, whether all the pieces of the reproductive tract are functional, whether the immune system works and whether the brain is wired properly. Compounds that mimic or interfere with these natural signals can derail development, send it off on the wrong track, subtley or grossly depending upon the timing and the magnitude of the interference. Third, we have seen a dramatic change in scientific understanding about the level of contamination necessary to cause an effect through this hormonal interference. We now know that there has been a paradigm shift in thinking about health impacts of contamination. The old way was too narrow, too limited, and that many-indeed perhaps the most important effects-would be utterly missed by standard approaches. The old paradigm focused on acute toxicity. How do high levels of contamination affect health? How do they cause cancer? How do they kill directly? How do they overcome the body's defenses, like a massive invading army overwhelming the defenders simply by brute force and large numbers? The new paradigm realized that there were other ways that contamination could work, work like a terrorist. Instead of an army, a small number of molecules could hijack the hormonal control of development and could cause intense, life long damage, undermining the immune system, eroding intelligence, diminishing reproductive capacity. This terrorist attack on fetal development works because the imposters can work at very low levels of contamination. sometimes at levels tens of thousands of times lower than the brute force approach considered by traditional toxicology. They don't need to overwhelm the system or kill it, they just need to insinuate themselves into the natural control process and add to it or subtract from it. Let me give you a few examples of the sorts of impacts that have been discovered in animal studies, both in the laboratory and in wildlife.
Phthalates in fact have been the focus of a fierce battle involving government, industry and environmental health proponents because, believe it or not, phthalates can be an important constituent of items designed to put in babies mouths, despite the facts that phthalates leach out of soft plastics, that they can proven toxic effects in animal experiments, and that the health consequences of long-term exposure to infants are unknown.
The
US fought this caution. Through the US Trade Representative's office
the government applied diplomatic pressure to dissuade Europe from
acting. Ultimately consumer activism from US organizations led toy
manufacturers
to begin taking phthalate-containing toys off the market voluntarily. These first three pieces to this story—the ubiquity of contamination, the reality of hormone disruption and the new recognition of the potential importance of low level contamination—are now well established scientifically through measurement and experiment. The fourth piece is not. The fourth piece is a question. Given all of that, what is happening out here in the real world to real people? We now know that significant numbers of people are now exposed at levels that cause problems in the laboratory. We know that people are experiencing syndromes analogous to these same problems. What we can't say with certainty, however, is whether what we see in people is being caused by contamination intefering with the mechanisms known to work in the lab. Let me give you some examples. Early puberty: Some data suggest that young girls in the US are reaching puberty earlier than before. This is not known for certain. It turns out that good studies documenting the age of puberty 50 years ago simply aren't available as a baseline. Accepting those early studies limitations, a paper released in 1997 suggests a downward shift in the age of puberty for American girls, and documents some strikingly early signs of pubic hair and breast development--measureable percentages beneath the age of 3 and significant numbers by the age of 8 and 9. These results and other reports are leading pediatricians to reconsider what should be "normal" to expect.
But while we don't know for certain that there has been a change, what we do know is that it is quite easy to affect the age of puberty in animals with modest exposures to hormone disruptors in the womb. Estrogenic exposure causes puberty to occur earlier in females. Anti-androgenic delays puberty in males. Hypospadias. Hypospadias is a birth defect of the penis. It is reliably produced in laboratory animals using certain anti-androgenic hormone disruptors like diethylhexyl phthalate (DEHP) and vinclozolin. Results from the lab suggested to the US Centers for Disease Control that it would be worthwhile to examine changes in hypospadias rates in the US. The resulting study showed a doubling of hypospadias since 1970. These trend data are firmer than that for the age of puberty, the animal studies are equally strong, and the only way for hypospadias to occur is for development to be disrupted in the womb. But, there is no firm evidence demonstrating, with scientific certainty, that human hypospadias is caused by endocrine disrupting synthetic chemicals. I should point out that there also are no studies that have been done that could prove or disprove that possibility with certainty. We are left with human trends consistent with animal experiments combined with certain knowledge that humans are exposed to the same contaminants. Sperm count. The best available data and the most sophisticated analysis to date indicates that on average sperm counts have declined by 40% over the past 5 decades. More detailed analysis clearly shows large declines in sperm counts in some places. Most recently reports have come in from China and India indicating large recent declines. As with hypospadias and date of puberty, laboratory work shows clearly that contaminants found in the human womb cause sperm count declines when fetal animals are exposed experimentally. This combination of evidence plausibly implicates endocrine disruption in the womb as a possible cause for low sperm counts measured today in many different geographic regions. There is, however, no scientific certainty. This has proven to be a highly controversial subject largely because the historical data on what sperm count used to be are so patchy and even the modern data are of such varying quality. Unfortunately, the data showing no decline, particularly from the United States, are almost invariably from studies using statistical sampling procedures that are biased (an example; another example). These studies have been useful to industry attempting to defuse concern over sperm count, but misleading scientifically. Disease resistance. Contamination's impact on the immune system is beginning to get serious attention with striking results. Let me briefly describe a study done by the US National Cancer Institute and the US Centers for disease control on non-Hodgkin's Lymphoma (NHL). NHL is one of the cancers whose incidence has been increasing steadily over the past 30 years. It had been thought that exposure to Epstein Barr Virus (EBV) was a risk factor for NHL. This study by the National Cancer Institute and the Centers for Disease Control reveals it is far more complicated, and also raises a much broader issue. They found that exposure to EBV alone is a negligible risk factor for NHL. Independent of EBV exposure, exposure to PCBs increases the risk to NHL by about a factor of 4.5. But if you are exposed to both EPV and PCBs, your risk of NHL rises over 20-fold. I believe that the effect of contamination on disease resistance is the sleeping giant of this issue. Contamination affects the immune system, undermining the body's ability to resist disease. With a weakened immune system, people fall prey to diseases they normally would have been able to resist. Traditional public health statistics would attribute their illness or death to the disease agent, not to contamination. This would lead to a vast underestimation of the importance of contamination in human disease. All the necessary science is not in on immune system impacts. Enough is available to know that it is a serious problem. I believe that within a few years we will have a new paradigm for the interaction between disease agents and chemical contamination. In essence, it will be that you can't understand the epidemiological impact of a disease agent, without knowing its contamination context. Intelligence and behavior. I will mention one result. Dr. Elizabeth Guillette found striking impacts on the ability of children to respond to a simple instruction based on their level of exposure to pesticides. She asked them to draw a picture of a person:
[An excellent report has just been published by Greater Boston Physicians for Social Responsibility on contaminants that are developmental neurotoxicants.] Looking at this diversity of evidence—from animals, from people, on sperm, hypospadias, behavior, etc.—what emerges is a mosaic of data all of which converges on the likelihood that these contaminants are affecting people in the real world, but it falls short of providing us definitive proof with scientific certainty. Thus this scientific case is not over. But I have concluded that enough evidence is available from a diversity of sources to conclude that exposures must be cut back sharply. We have an experiment underway in the bodies of people and the wombs of mothers all over the world, one whose results may not be evident with scientific certainty until long after it is too late. Let me mention to important proofs of the enormity of this experiment. The first is an analysis carried out by Environmental Defense showing how little experimental toxicology has actually been done to test the safety of most chemicals in widespread use today.
The answer was stark. Most chemicals in widespread use in America today have not been tested for safety. And while industry lawyers might have us believe that the absence of data is proof of safety. Nothing could be further from the truth. Absence of data is proof of ignorance. It is proof of the vast experiment that has been unleashed unwittingly on Americans, indeed global citizens. One of the most striking of these experiments is the ubiquitous use of bisphenol A. BPA was first synthesized in the late 1930s during the effort to create artificial estrogens. Not as powerful as diethylstilbestrol (DES), which was invented during that same rush, BPA was put on the shelf until someone discovered that when polymerized it formed a very useful plastic, polycarbonate. As polycarbonate it has entered consumer society in a myriad of forms, including plastic water bottles, plastic baby bottles, coating for kids' teeth (to reduce the likelihood of cavities) and the inside coating of food cans (to minimize food interactions with the can). Only recently with work by several different laboratories, notably those of Nicolas Olea in Spain and Fred vom Saal in Missouri, have we learned that bisphenol A is extraordinarly potent at endocrine disruption and also that the quantities of bisphenol A that leach out of these plastic products and processes cause exposures to people at levels known to cause strong impacts in animals. My point here is that bisphenol A is out of the bag, everywhere, including in the mouths of children, and we have no confirmation of safety. Instead, we have indication of significant risk. But we have a system that allows the contamination in an uncontrolled experiment in the real world instead of insisting first upon a demonstration of reasonable safety in the lab. In this country the regulatory apparatus is proceeding very slowly. There's no question why. The paradigm shifts involved here create an enormous challenge for the use and manufacturing of chemicals as it is now practiced, and bless our political system, those with vested interests and lots of money are using the money to protect their interests. Which is where you all might come in. I said at the outset that a new dimension to the fight over reproductive rights may be emerging. This is it. Our current approach to the regulation of chemicals permits chemical trespass in the most intimate environment of all, a mother's womb, with no information about safety. It threatens to create a world in which impaired fertility is common and in which, as a result, only the rich can afford the medical interventions that allow them to reproduce. It threatens to create a world in which children grow up at heightened risk of disease, with intellectual impairments, and with their own fertility problems. This is not a just world. Here's the problem. We know enough about the science here to realize these patterns of contamination create plausible risks, risks established from a wide body of evidence. We don't understand it all, but what we do know is very disturbing. But industry lawyers and their scientists can argue legitimately that the level of proof is not certain. And that's true. Just like the level of proof for tobacco and cancer wasn't certain, for decades after reasonable people concluded that enough evidence was available to finger cigarettes as agents of cancer. We're getting the same arguments today. And worse, I can tell you that details of the science of hormone disruption make it vastly more difficult, if not impossible, to obtain enough certainty to satisfy industry's lawyers, as long as we live in a society constrained by morals from conducting planned scientific experiments on people. Epidemiology won't deliver a final verdict for decades, if ever. And in the meantime, unless we act to reduce exposures, we condemn additional generations to additional unplanned, uncontrolled experiments. These are experiments whose results we will not know until it's too late to call them off. It's the sort of experiment that would be rejected by any medical ethics board in the world. Medical experiments on people begin with the premise of prior informed consent. And I ask you. Who asked us? Who asked us for permission to perform this experiment. Don't you have the right to make reproductive choices? These contaminants interfere very directly with those rights. What we need is a dramatic change in the standards of proof for what chemicals are allowed to be used in products and processes that have led to that fact I mentioned at the outset, that each of us carry several hundred novel chemicals in our blood. We need to be far more cautious about letting chemicals move from the lab into the marketplace. We need to demand much more evidence that chemicals don't cause harm. We need to acknowledge that there are some contaminants whose risks, although still uncertain, are so large that we simply won't let them be used or produced in commerce. We need to insist that experiments take place in the laboratory, not in our children's bodies nor in the wombs of our mothers. Thank you. |
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