TERRY COLLINS: It's my very special pleasure today to introduce to you, Professor Fred Vom Saal. Fred is the greatest professor at the highest rank at the University of Missouri at Columbia. Fred is really an epic scientist in my opinion, in modern American Science. He began looking at low dose, he is an endocrinologist, he began looking at low dose adverse effects of a very common chemical, Bisphenol A, well over 15 years ago and I guess. And published results that were highly problematic for the on-going use of this compound, which we make about 6 billion pounds in the US alone and of which we put into an extraordinary array of products. The progress of Fred's scientific-academic life from those initial complications is quite an extraordinary story. And it goes all the way to really straightening out or setting the vectors up to really straighten out the way science is done at the FDA and at the national level. Fred is an iconic figure in endocrine disruption. The things that he has done to make the country, make corporate America look at very serious issues associated with the low dose adverse effects of everyday chemicals is completely extraordinary and I'm truly delighted that he could be here and share his insight and incredible science and knowledge with us today. Please welcome, Professor Fred Vom Saal.
PROF. FRED: I would like to thank Terry Collins for the invitation and I’ve had a wonderful day here looking around this really, just spectacular university and very impressive facilities. And so, what I want to do today is to give you an idea of the mess that our system has evolved into with regard to assessing the risk posed to everyone in this room by chemicals that are presented to the public as completely safe. And the reason that the system is a mess is that there is a huge amount of science generated and practically all of it is ignored by Federal Regulatory Agencies. And with the Obama administrations, people brought into the Federal Regulatory Agencies, it's-- we are experiencing, for the first time a shift in attitude and it isn't just a shift in attitude from the Bush administration. We had just as vigorous arguments with the people in the Clinton administrations as we did with the Bush administrations. So, it's really been very bipartisan in terms of being anti-science.
So, what I'm going to do is talk about a molecule that, about 20 years ago, I've never heard of. I'm an endocrinologist, I am not a toxicologist and-- But this is a sex hormone. This acts like a sex hormone - estradiol, a hormone that everybody has active in his or her body, men and women. And so, it really falls under the domain not of toxicology but of endocrinology. I started studying this as in endocrinology and infuriated toxicologists by doing this. I thought I’d tell you about this story which has been kind of a strange one.
So, Bisphenol A is used to make plastic. And as we know, plastic is fantastic, that's-- And we live in a plastic planet and it's pretty much revealed by this picture, it pretty much says it all. We are being absolutely inundated about every two and two and a half years, a trillion pounds of plastic are made. Most of them are thrown away in the landfill. The rate of recycling is relatively low. In addition, they beautify our rivers, and this is the Los Angeles River flowing out into the Pacific Ocean, where one of the best characterized cyclonic events that occurs in all oceans where you have this flow of water that actually concentrates debris in the middle of what is termed, the Pacific garbage patch. But this occurs in the South Pacific, the North Pacific, the
Indian Ocean; all over the world. You have these events occurring where you have this massive contamination of debri accumulating that is going to be an ecological nightmare for the future. And one other thing you'll notice, this is Hawaii, and the flow is down here. So, here's a typical Hawaiian beach, which many people in geology believe when it comes to looking at our era, what is going to characterize our era is massive concentrations of plastic, everywhere because there's just so much of it made.
Now, there is a huge price being paid by aquatic wildlife, migratory birds that are surfing along the water, and eating up all of this plastic. Now people always ask me, how do I know one plastic from another. And the plastic industry was phenomenally clever and nobody ever licensed the recycling code. Practically, all these plastics are non-recyclable, and the city I live in, they'll recycle the ethylene base plastic, polyethylene terephthalate, sand high-density polyethylene one and two. The rest of and them, they won't take. You don't want to recycle polyvinyl chloride, it generates dioxin, polystyrene; and polycarbonate is not a recyclable plastic. And so, the idea that they're putting recycling codes on them is pretty amusing, to begin with, because they are not recyclable. And all they do is basically tell you the base polymer, and the reality is that there is no such thing as a pure plastic. All of these plastics like we know there are phthalates, which blocks testosterone production that are also required to make polyvinyl chloride, they’re released from the water bottles, that you get. There you go, you want to get a hit of phthalates? Take a drink. Also, you get trace metals out of them; the older, warmer they get, the more they release. There are--
These are all petroleum products, and they practically all have brominated, flame retardant sur phosphated flame retardants. Then there's Tetrabromo Bisphenol A, which is the highest volume flame retardant and these are all neurotoxic. So, if there is a safe chemical, I don't know about it, but number seven is-- essentially means none of the above, over 90% of it, 95% is Bisphenol A, this extremely high volume chemical that I'm going to talk about, that I stumbled onto by accident.
It's estimated that last year about 8 billion pounds were made, the amount going up 10% a year. It's one of the highest volume chemicals in production. It's used in so many different products. It lines cans, it’s used as dental sealant and dental filling, to make all kinds of plastic products, plastic wrap. And my research assistant took some receipt paper held it in her hand and then wiped her hand off and had thousands of micrograms of Bisphenol A on-- that she had on her fingers. She had touched food with that, she would have been massively exposed to it.
The receipt paper is coated with free Bisphenol A. It’s not in polymer form, it's like talcum powder being on it. Put your hands on it. It's just on your hands. You stick your hands in your mouth or you touched food, you touch your clothes, it is clearly a major source of contamination in humans.
But when Bisphenol A is polymerized to make polycarbonate plastic, it's polymerized in a reaction that is linking these Bisphenol A molecules that are a synthetic estrogen. But when in a polymer form, they are not estrogenic, this big long chain.
The problem is, under increased acid or base or increased temperature, ester bonds are hydrolysed and release free BPA. So, you buy a baby bottle and you're told to sterilize it. While the moment you start doing that, you are degrading the quality of that plastic and releasing into anything that you put into that baby bottle, namely, your baby’s food or any other polycarbonate item or a tin can that’s lined with Bisphenol A and is heated to hundreds of degrees in order to sterilize the food in it. You are impregnating that with Bisphenol A. And so, we measure Bisphenol A using a variety of techniques; we were using LC with mass spectrometry on this, and you can see that the acidic tomato sauce gives you a high hit. Peas are always high. This is a rubber-made container called microwave-safe, soup cans. What I'd like to point out is that this is in part per billion levels and these are considered extremely low levels and so the public is very easily misled into thinking: “That's an extremely small amount. Who could care about that?” Well, the answer is “You should!”
And these are Eddie Bauer sport water bottles. These are brand-new. As they get older, they leach, maybe 10 times more, okay, but these are brand-new. These are all of the major brands of baby bottle that up until a year ago, when, due to our work in other people’s; all of these corporations gave up and stopped producing polycarbonate baby bottles, they are using alternatives. Hopefully, they will come to Dr. Collins, and get some help and replace them with safer and not more dangerous chemicals.
And so, Bisphenol A is what is called an endocrine disrupting chemical. And endocrine disruptors have to do with disrupting hormones that control the coordinating-- they are the coordinating systems of our body. They control your metabolism, your reproduction, just all of the systems in your body. And these endocrine disruptors act in adults to cause harm. All right, on the other hand, the focus has primarily been on development because the same hormones that control your adult systems, also control foetal development. And the difference is that a woman can take an endocrine disrupting chemical- ethinyl estradiol in birth control pills. And while she's taking it, it disrupts her ability to reproduce. When she stops taking it, she can recover and reproduce. So, these are transient in general effects. If you expose a foetus to an endocrine disrupting chemical during the time tissues develop, that effect, essentially puts the foetus on an entirely different developmental path that can never be reversed.
So, it's not that adults are not at risk with chronic exposure to these. You can get cancers, metabolic diseases like diabetes because you're exposed all the time to them. You can't get away from these chemicals. But we’re primarily interested in foetuses because a single hit during the time that an organ is developing will permanently change the life of that baby. And this example is pretty extreme, but it really gets the point home. The control of the development of the penis versus the vagina and the clitoris in the female is under the control of the sex hormones testosterone and estradiol. And we can manipulate these hormones and take a female, XX female and make her have these organs. All right, so, if you fool around with hormones during foetal development, you can definitely cause some observable changes. All right, it’s not-- these don't have to be subtle. Everybody says, “All these are subtle changes”, I don't think that's too subtle. But there are lots of other subtle physiological metabolic changes that go along with this that are harder to see and make life much more difficult for physicians.
So, what is Bisphenol A? Here’s estradiol, here is one of the most potent estrogenic drugs. It was given to millions of women during the ’60s, ’70s, ’50s, and it was thought that they needed it to stop from spontaneous abortions. Instead, all it did was cause cancer, infertility and disrupt the life of millions of children born, whose mothers took this during pregnancy. So, it's a carcinogen. And Bisphenol A does pretty much everything DES does, or the estrogen in birth control pills, ethinyl estradiol. It is a man-made, estrogen, and it was known to be an estrogen in the 1930s. And before people like Terry Collins came along, chemists in the 1950s thought, “Oh let's take this sex hormone, make baby bottles out of it! Wouldn't that be a great idea?!” I don't think so, but they apparently did and they did that.
And so, this idea of green chemistry where you are thinking of the consequences of the
chemicals you are using to make the products that we’re now using in our everyday lives, this is
something that has been really, one of the major initiatives at Carnegie, that people in the world I live in are so excited about, that we won't make these mistakes again.
So, the way estrogens work is they get into cells, and they bind two receptors that activate genes. And estradiol binds to its estrogen receptor and activates estrogen-responsive genes to change cell function.
Bisphenol A can get into cells and do exactly the same thing estradiol can do. Bisphenol A does
some other things. I mean, this is like your, you name it and it's bad and this chemical does it. It
also binds to the receptor for the males for the thyroid hormone. And that's critical for brain
development and when it binds to that, it blocks its ability to function. And so, it interferes with
normal brain development, low thyroid hormone, low IQ, brain damage. It also binds to the
receptor for male sex hormone and interferes with its action. So, here you take a developing
male baby, you block its ability to respond to male masculinizing hormones. You estrogenize it, and you inhibit the ability of its brain to form function, normally. Relatively bad set of events.
Not only is it doing this, but it is also doing something else called gene programming. So, it isn't just that it's blocking an event or activating an event, it is permanently altering the ability of these genes to function. And it does that when we usually think of chromosomes. And if you look at the parts of the chromosome and you unwind the protein coat and you look at the protein coat that the DNA is wrapped around, you find that there are specific regions of the DNA that these chemicals can activate an enzyme methyltransferase that will just stick a little methyl group on the DNA. It doesn't cause a classic mutation. That methylation event silences that gene and it no longer functions. It's equivalent to a classic mutation. So, these chemicals can re-program gene function and once that's done, it's permanent. Alright, so these are genetic programming chemicals.
So, we actually have an understanding of the molecular mechanisms by which we do this. So, if you think about what I was taught. Probably many people were taught about the way heredity worked. It was just heredity is all a matter of genes. This idea of the environment through epigenetic mechanism determining which genes act normally and which genes don't is really a new idea. It is now the major emphasis of research in Biology, particularly Developmental Biology. Last time I checked, over a thousand NIH grants were devoted to studying that issue.
So, one of the important things is the issue as Terry Collins mentioned that what is become the huge argument in endocrine disruptive research is, first of all, these chemicals operate at levels that most people would think are too low to matter. If I say a part per billion, you would think that can't possibly matter. And the other thing that is really scary to them is that high and low doses of endocrine disrupting chemicals don't do the same thing. And in classical toxicology, they only study high doses and nobody has ever studied the amounts of chemicals that we are actually exposed to, which are these very low part per billion levels. And this idea that the high and low dose effects lead to what are called U-shaped or inverted U-shaped dose-response curves.
So, in classical toxicological thinking, the idea is “more is worse”. Makes sense if anybody would think this, all right, if a little bit as bad, more is more bad. If a little bit as good, more is morbid.
Well, that turns out to not be true for hormones. But it is the fundamental assumption of
toxicology that dose-response curves are monotonic, they go in the same direction. And that
there is a theoretical dose that causes no effect. All right, below which you don't have anything to worry about and that you can test very high doses and they'll tell you everything you want to
know about what low doses do. The problem is that this became dogma in toxicology and
nobody ever got around to testing doses of chemicals that are actually in the human body. So, all of the chemicals that you're exposed to, that you're told are safe, the very few of them
that have actually been tested, have never been tested at the amounts you're exposed to. But you’re told those amounts are completely safe in the complete absence of data. And I committed heresy. I actually started testing doses that were not only at the range of human exposure but below it and the toxicologist got extremely angry with me because they said, “No, we don't do that.”
So here's, the paradigm of toxicology. They go find an amount of very high dose chemical that causes an acutely toxic effect. It used to be the amount that killed half the animals now. It's the amount that makes the animals really sick but doesn't kill them. And then they’ll test maybe two or three doses and they'll predict from that, a dose that is likely to cause no effect. Often, they don't find a dose that causes no effect. They just predicted and the idea is the system is completely at zero function at this threshold.
One of the problems with endocrine disrupting chemicals is that we have endogenous estrogen that chemicals like Bisphenol A add to. And so, what you really have to do is look at the total amount of estrogen present. Not, it is not possible that there is no estrogenic activity at this theoretical threshold, because you have all of your own estrogen and then this exogenous estrogen is adding to it. And it turns out that natural estrogens first increase activity and then decrease activity of specific responses. So, this is a fundamental characteristic of all hormones. All right, I teach undergraduates endocrinology. This is in every endocrinology book. This is in every endocrinology course and yet it's not accepted as a possibility by people in the chemical risk assessment community. So, this is just a summary to basically say here you have these principles of toxicology that assumes that as dose increase effects increase. This is classically stated as the dose makes the poisons. The core assumption of toxicology and is based on 16th-century hypothesis by Paracelsus. And just for Bisphenol A, there were over 20 studies showing that this is not true, all right. But, you know, if you don't believe something they don't matter.
So, when I started publishing about this, industry made some very funny comments about me. But one of the things that they said, that the reason I put this up here is not to show they were making funny comments, but that they were making incorrect comments. That what they were saying is that what I was really implying is that high doses were safe and low doses were dangerous. What I'm really saying to you is that high and low doses do very different things. And if your premise that high dose testing predicts low-dose responses, that's false. High doses can be very toxic and very dangerous. They're just going to do entirely qualitatively different things than low doses do. And so, they're not predictive of the dangers posed by low doses. That's very different than what they're stating here, they’re misrepresenting the issue.
So how is it that a hormone can do something different at a low and high dose? These are very very simple data. These are from an FDA conducted study, by a friend of mine who's a research scientist at the Food and Drug Administration. And he took the uterus of a rat and he started giving higher doses of estrogen and one of the things you see, this is a characteristic of
steroid hormones. At low doses, they increase the number of receptors available to respond to
them. They increase the sensitivity of the tissue in terms of the tissue's ability to respond to the
And that's also true for Bisphenol A, it stimulates the production of estrogen receptors. But you get to a certain dose and then it completely shuts down the ability to make the receptors, okay. So, at high doses, the tissues become very unresponsive to the hormone. At low doses, they become more responsive. Exactly the opposite, predicting inverted U dose-response curves.
The other things that happen, is at this point, it is primarily these chemicals and estrogen are causing effects through binding to estrogen. When the estrogen receptor system is shut down at high dose, these estrogen molecules start binding to all of the other receptors in the cell.
There's a lot of receptor crosstalk at very high doses, and so all kinds of weird stuff that would
never happen at a very low-dose when the affinity is not high enough to bind to all of these other receptors. You just see estrogenic responses, up here you start to see all kinds of hormonal systems disrupted. Again, qualitatively, totally different responses.
So, I thought I'd give you a very simple example of this in a clinical setting because practically everybody knows what the drug Tamoxifen is. It’s taken by millions of women for breast cancer and here's an example using human breast cancer cells from our laboratory at the University Missouri and my colleague Wade Well Sean's, who does this work with me. And what we did here is you put a little bit of estrogen in and you stimulate growth of human breast cancer cells. And then you start adding Tamoxifen to the system, which, remember, is an anti-estrogen, blocks breast cancer. Only problem is, at this low dose range, it stimulates breast cells to proliferate. When a woman is put on Tamoxifen therapy, she's going to be told, “You may experience an increase in bone pain, you may experience an increase in discomfort.” As you go through this flare reaction in the low-dose range, where this is estrogenic. And then as you get up to this high therapeutic dose range, it will start blocking estrogen. It does exactly the opposite at high and low doses. This is true, for if you have prostate cancer and you're taking Lupron, low-dose flare reaction, high dose inhibitory effect on prostate cancer. And if the doctor lets the dose in your blood get down into this range, it will kill you! Okay, so you got to be very careful if you're taking these drugs.
So, this is a characteristic, again, of all hormones, all hormonally active drugs, and all hormonally active chemicals. So, and again we get back to the part per billion issue. So, I told you Bisphenol A is active in the part per billion range and everybody says, “Oh! It's really weak. It’s a really weak chemical. It is weaker than estradiol”. Absolutely, estradiol can operate to stimulate human breast cancer cells at the lower part per trillion. So, Bisphenol A is about 10,000 times less sensitive, less potent than estradiol, okay!
But this is still a tremendously small number, all right. So, estradiol happens to be one of the most potent hormones known and Bisphenol A is not as potent as it but it's still operating in a
staggeringly low range. Remember, one part per billion Bisphenol A can cause an effect on all these tissues. It can cause prostate cancer, pancreatic cells, pituitary brain cells to proliferate all kinds of things.
This is the average amount of Bisphenol A in human male foetuses, and here foetuses in female, 2 to 3 parts per billion. The bottom 5th percentile is point one parts per billion and the top is about 10. So, it's about a hundredfold range and the middle is 2 to 3. We are dead centre in the bioactive range of Bisphenol A, and that's what we’re exposed to. And we’re told, “Oh it's really weak. Don't worry about it.”
So here's a baby getting its daily dose of drugs, and it’s from just drinking baby formula out of a bottle. The US National toxicology program estimates it's getting about 5 µg per kilogram per day. And I tell you that because at 25 µg per kilogram per day treated with a pregnant rat and looking in the foetuses, you have over the 24-hour period, approximately 1/10th in a rodent foetus of what's in the average human foetus, all right. And I’m going to show you some data of what this does to a rodent baby. And I’m going to do this by showing you some of our data on the prostate this gland located below the bladder, the urethra runs through it. It was put there to torture men as they get old by getting big and constricting the urethra are killing us by becoming cancerous and I am going to also show you that these glands of the prostate also run down the urethra and cause all kinds of problems and I'll show you some data on testis.
So, one of the first things we did was we, fed females the Diethylstilboestrol just to look at them with a very well-characterized estrogen from very low doses to one that was clearly toxic. What do we find? Exactly what I told you, low doses in adulthood. So, this was just treating the mother with these doses; after birth, these animals were never touched.
In adulthood, we look at their prostates and the low-dose animals had enlarged prostate. The high-dose animals had small prostates. So, we went on the second day of prostate development in the mouse foetus and what you see in the prostate at this time, here's the bladder and here's the urethra and the prostate glands are beginning to bud out of the urethra because eventually the prosthetic fluid that forms in the seminal fluid is going to come down these glands into the urethra and join with the sperm, become the seminal fluid. And so, what we do is we dissect out the prostate from the foetus, section it, and then scan it into the computer coding all the different regions. And here are the dorsal glands of the prostate, the lateral glands, glands the ventral. And the computer also reconstructs the urethra and that's very important because--
So, here's what a high dose of Bisphenol A does. On the second day of prostate development, there are no glands. It kills it. So high dose of estrogen completely blocks prostate development, all right? It’s just goodbye, nothing there.
If you get down much lower, so, instead of 200 µg per kilogram now you're down in this .1 µg per kilogram range, you know, 2000 times lower. Now what you see is a huge relative to control animals increase, in prostate gland number, in prostate gland size and what really intrigued us is-- here’s the bladder, neck, and here's the bladder neck of estrogen, estradiol, or Bisphenol A exposed animal. It's massive, it's tremendously constricted relative to what it is in an untreated animal and the glands are clearly being stimulated and this is just to give you a quantitation of that.
The size of the prostate on the second day of development in the foetus and the exposed Bisphenol A is already two times larger than normal and so we can take the individual
sections and immune-stain them for proliferation using proliferating cell nuclear antigen that's only expressed during mitosis. And we find these cells doubling in their rate of proliferation and by counterstaining with another antibody, we can identify them as the prostate stem cells.
So, Bisphenol A is causing the stem cell population of the prostate, start abnormally proliferating. And when we go in and we look at the genes that are involved in this, all of the stimulatory growth factors are being up-regulated by Bisphenol A and estradiol and the growth factors that would normally suppress growth are being down-regulated. So, one of the conclusions here is that you're not going to find any of this stuff out testing high doses. The assumption in toxicology that because you've got a low dose of Bisphenol A you don't really need to worry your high-dose testing, says none of this stuff is going to occur. That's just not true. This is just some of the adverse effects that we see occurring in the human population over the last 20 to 30 years. There were 50 million pounds of Bisphenol A made in the early 1970s; there are 8 billion made today, massive increase in the use of this chemical.
These are diseases that are occurring in the human population - breast and prostate cancer have been steadily going up over the last 40 years; the incidence of hypospadias, according to the CDC, doubled between 1970 and 90. There’s been a gradual sperm count decline in some regions, not others. We’re worried about early sexual maturation of young girls. Polycystic ovarian disease and uterine fibroids, increasing incidence of miscarriage. We know obesity is going through the roof. Type II diabetes is now occurring in children. I was taught as a student; it was adult onset diabetes; heart disease.
What we now see is there is clear evidence from both animal and human studies that type II diabetes, insulin resistance, high glucose in the face of high insulin occurs in both human epidemiological studies and animal studies and we understand in great molecular detail, how this is occurring in the beta cell of a mouse.
We know that miscarriage is caused in rodents by abnormal chromosome… occurring in females. Bisphenol A in rodents causes uterine fibroids and ovarian cysts. It causes early puberty. We published that in Nature and 99. We published that sperm count decreased, that's been repeated about in 10 times. Early puberty has been seen in at least 10 different studies and I've shown you this urethral obstruction, and a colleague at Rochester and I are going to be co-publishing set papers on that, so that's been replicated.
One of the important things is practically everything you're looking at here has been replicated and the thing that is really scaring people is that the brain is probably the most sensitive organ to endocrine disruption and this is a poster sought child chemical - ADHD chemical. It causes learning impairment when exposure occurs during development and animals are hyperactive. And none of the social behaviors of animals are normal and interestingly normal gender differences in behavior are virtually eliminated by BPA, which is fascinating. The effects in males and females are never quite identical in the brain.
So why all the argument? We have hundreds of studies in animals funded by the government showing that range of adverse effects. There are over 200 studies that represent those findings, all funded by the government. And then hundreds of additional molecular studies… about… this molecular mechanism underlying all those findings. There are 15 government-funded studies that have not found effects. We’ll talk about them.
Then the chemical industries come along. They have conducted 15 studies, every one of them claim Bisphenol A is safe. Not all of them contain data that show that, but that's a conclusion from every one of those studies. So, we have a very interesting, very skewed distribution over 90% of government studies showing harm. Again, hundreds and a hundred percent of industry studies saying, “Completely safe, don't worry about it, one little bit.” And so, what is this all about, well, this guy David Michaels, who is now in the Obama administration after some tremendous fight at the, is it OSHA?
PROF. FRED: Occupational Safety and Health and he wrote a book based on this called ‘Doubt is Their Product’. It’s really a distressing book to read because this was taken from a tobacco industry document where the lawyer basically said our job is to create doubt about legitimate science, which of course was part of the tobacco settlement that this information had to be released.
And then the coup de grace was the smoking gun found by a reporter for Chemical and Engineering News, who found the letter from the Weinberg Group who used to work for the tobacco industry and is now the chief product protection firm for the plastic industry. They wrote DuPont about Teflon chemical PFOA and this is what they wrote: “We will harness, focus and involve the scientific and intellectual capital of our company with one goal in mind - creating the findings you need to protect you in court.” That's, I mean, that's essentially what they're saying. So, we’ll just manufacture science and… publishing this got Paul Thacker fired from Chemical and Engineering News. They didn't…
AUDIENCE: Environmental Science and Technology
PROF. FRED: Yeah, environment, excuse me, Environmental Science and Technology, yes indeed… What did I say, Oh I’m sorry, the wrong journal, and they're very unhappy with him, disclosing that.
One of the things that I thought that I would point out to you is that what has become a really big issue in this, is that there have been specially bred animals over the years, to be bred for different reasons. Charles River took a rat that they bought from Sprague Dawley in 1950, and then started selectively breeding it to produce monster litters and become huge animals.
So, these animals’ growth curves are just, totally unbelievable and they produce huge litters of animals, 50% more babies per litter than the original stock. The only problem is in the process of doing that, the birth control pills, ethinyl estradiol, the estrogen and birth control pills is effective in 99.97 women i.e., only 3/10,000 women don't respond to a .3 µg per kilogram dose of this. But these rats, some of them require up to 200 µg per kilogram to show any effects of this estrogen. So, these animals have been bred along with being huge and huge litters, they’re extremely unresponsive to estrogen. 15 Bisphenol A studies have been conducted with these rats and all of them show nothing. And that accounts for most of them have been fun, except for two or three by the chemical industry that accounts for all practically all the government studies that don't show anything.
So, the chemical industry ran one study with this rat back in 2002 and the National toxicology program looked at it and was extremely critical of the author and it was funded by the chemical industry and they said, “We know there are huge strain differences the way they respond to estrogen. And so, animal selection should be based on the ability to respond to positive control estrogens.”
So, if you look at this situation where this animal is clearly unresponsive within the human range of response, they deemed this study by this Tyl et al to really be unacceptable, because the animal was so clearly insensitive to the positive control estrogen.
The mouse that I use, we published this in Human Reproduction, responds to an ethinylestradiol. Here's the clinically effective dose in women and our mice show a decrease in sperm production at .002 µg - a hundredfold lower dose than what women are sterilized by and this is not, this is obviously not the lowest dose that women can respond to, but the clinically effective dose in virtually a hundred percent of women.
So, we know that women are responding in this range and we believe that this mouse and so does the National Toxicology Programme uses this, but this is a very effective mouse to use for BPA and other estrogen research and remember, .002 is 10,000 times slower than a dose of Bisphenol A administered to pregnant females in adulthood. You look at daily sperm production just like we did back here. These were just exposed to foetuses to ethinyl estradiol.
In adulthood, looked at their sperm production just exposed to Bisphenol A as foetuses in adulthood how much sperm, permanent inhibition of sperm production relative to the normal amount and but it took 10,000 times more. But remember, this dose of Bisphenol A generates 1/10th the amount of Bisphenol A in the blood of these babies relative to what's in the human normal human foetus. Just due to its mother being exposed to this chemical.
So, a study was just published that just blew people away because it was so absurd, they used another rat that's extremely insensitive. They published a male paper and a female paper, I’m just showing you the-- from the same study. So, these are what the males and the females all took 5 to 50 µg of Bisphenol, of ethinyl estradiol to show a response. This is the clinical range of, so clearly, these rats are very insensitive to estrogen. And our data show that if it takes 50 micrograms per kilogram to show an effect of the ethinyl estradiol you need 10,000 times more of that of Bisphenol A to see an effect. That's what our data show and that's what dozens of other studies show consistent throughout the literature. And what they did was they had a completely irrational set of Bisphenol A doses. This is only four times higher than the stocks.
And so, 24 scientists got together and published a letter in this journal - Toxicological Sciences and said this is a kind of study that is contaminating the scientific literature. And this letter is online right now or it's actually appearing in this… it’ll appear this week in the journal. It is signed again by 24 scientists saying the journal has to stop publishing this kind of research that is clearly not being reviewed properly because no one would predict an effect of these doses of Bisphenol A.
And the journal editor went out and found this poor guy who they got to write this editorial in which he said this one article essentially, “Gee! Is it time for us to completely forget about any concern about Bisphenol A?”, and he also attacked the National Institute of Health for funding Bisphenol A. He also basically said, “I really don't know much about this subject. I'm really uninvolved in this.” So, he may be sort of the deaf, dumb and blind little guy who they got to write this letter who’s really embarrassed the hell out of himself. But we really do have a problem with this journal because, at the same time, we have the National Institute of Health setting a set of criteria that it has established for funding research not only on Bisphenol A but other chemicals, that is, you need to include appropriate positive controls; establish what range of sensitivity your animal has and then you set up your appropriate doses of Bisphenol A or whatever.
You need to use an animal that is at least as sensitive as humans. Clearly those rats I showed you didn't meet that test. You need to use state-of-the-art methods which you tend to find in an NIH funded research which is very competitive and you have to measure internal dose and measure a wide range of doses. In all of our studies, we are now measuring. It's not rocket science to use LC-MS to measure this. So the chemical industry just funded a study – it's online in the same journal toxicological sciences and they violate every one of the standards established by NIH to do this kind of research. Is it that they don't understand them? No, clearly they do. They didn't measure the internal dose. They had no positive controls, they use this staggeringly insensitive rat and they don't really use appropriate methods in this study. So my conclusion here and the conclusion of the 23 other scientists that wrote this letter with me is that one of the problems we face is the chemical industry is now conducting this research clearly not to advance science, but to use in court and to use for stimulating the kind of regulatory changes that they want and that there are journals such as the Society of toxicology that have become vehicles for funding for publishing flawed research and this is exactly what we say in our letter that this research is contaminating the scientific literature because clearly, they are not going through an adequate review process. So one of the things that I would end by saying is that you know Bisphenol A we know it operates through similar mechanisms in animals and humans. It causes a wide range of adverse effects in animals and in humans at doses that are present in humans and this really is concerning and that we are seeing effects in animals that are really low and one of the things that this suggests is that humans are actually well within the range of harm based on current human exposure levels to this chemical. And this really is somewhat unique. A lot of toxicology involves testing very high temp levels of chemicals and we have no idea what the levels in our bodies are really doing and the reason Bisphenol A is out there is, it was declared generally regarded as safe in 1963 and approved with no information being known about it and most people don't understand that the FDA drug side requires testing efficacy and safety prior to use. Whereas chemicals in food, there are no studies of health effects and until there are data such as we have with Bisphenol A nothing stunt about them there just declared, generally regarded as safe, they are grandfathered in. And while the FDA states that safety means that there is a reasonable certainty in the minds of competent scientists that the substance is safe under the conditions of use. But they recently said in a January press conference- ‘we really recommend that people reduce exposure to this, we recognize it's a problem’. Unfortunately, we have no regulatory authority over this chemical. We can't even find out the products it's used in. We don't have the authority to even go to the industry and ask where it's used, this would require extensive rule-making or new legislation from Congress. And that's really depressing because that also applies to tens of thousands of other chemicals used in products. This is the industry's response to all of this. They ran this Ad all the time saying ‘this stuff is great, eat it, be happy’. It’s kind of hard to imagine. Anyway, I'd like to thank my collaborators and my students and my research associates who have helped with this and I thought I'd leave you with some websites where you can get a lot of follow-up information to what I just talked about. A lot of the details you can find on these websites. So I'll stop there.
TERRY COLLINS: Well thank you very much, Prof Fred Vom Saal. We could take questions now.
AUDIENCE: Fred, it was very convincing to show the different methods of (inaudible), but most of the facts is still surprising, and this is why I would ask you to help us to understand if you have any molecular mechanism as to why this is going on. Why this is happening? Because I can understand something like, we measure at this concentration as (inaudible) taking you to lower concentration, there should be an (inaudible). But here the situation is totally different. (inaudible).
PROF. FRED: Well, but there's one thing that I did leave out that I think might be helpful and that is, there are many types of receptors in the nucleus for instance. And they are part of what is called the nuclear receptor superfamily and there are dozens of them. One of the things that happen is at very low doses, estrogen only binds to it's only read its own receptor because the affinity for other receptors like androgen or thyroid or mineralocorticoid receptors or whatever, the affinity is very low and it requires an extremely high concentration to bind to those receptors. So what happens at very high receptor at very high concentration is that you get what is called receptor crosstalk and now at high doses, it is interacting with response systems. It would never interact with at low dose and the consequence of that is, as you increase dose and you do Microarray analysis of gene activity, you see entirely different arrays of genes expressing across the dose-response curve. And one of the intriguing things is you see genes that are involved in inhibiting responses stimulated at high doses. Those genes are not expressed at low dose; you see stimulatory genes expressed at low dose. Just like I showed some of--. So we actually have a reasonably good molecular understanding that you should never see the same qualitative effects at low and high dose. You have different arrays of genes and different arrays of receptors.
AUDIENCE: It is well known for many many years the basic principle of endocrinology is negative feedback in (inaudible). So, at very low dosage it is stimulation, when we get a very high dosage, its negative feedback in short span. (inaudible)
It’s expensive and this has a relatively short half-life. One of the scary aspects of this given that it has a short half-life it's present in everybody's blood in the United States. The CDC found it in 93 to 95 percent of people and for something that only lasts a couple of days that means that there is essentially chronic exposure to this. Since the FDA and no one can find out what products it’s in and a person who wrote a book called slow death by rubber duck cut, Rick Smith. It’s actually a fascinating book and he set up an experiment and he dosed stems, he ate a meal full of Bisphenol A from BPA products. His dose level went up sevenfold, but when he went to do everything conceivable to avoid it, he went back to the average level in the United States doing everything he could think of to avoid this chemical. And he couldn't get it out of his body. It's until we have legislation and the toxic substance control act is trying to do this in industries, fighting it like hell, that allows a government agency to find out what products the chemicals are used in. You can't avoid this chemical because we have no idea what it's in, and therefore we have no idea how to avoid it. We know it's in cans, we know it's in polycarbonate drinking bottles and stuff but that alone, avoiding them isn't going to get it completely out of your body. It is very frustrating.
AUDIENCE: It is sort of a political question. If you have an idea to get rid of polycarbonates and you yield money to do the research, how do you make sure your proposal lands in the right hands?
Well luckily, the NIH panels are phenomenally, the ones that I go to - our endocrinology panels. They don’t know this chemical from a hole in the wall and they're not political about it. If I were to go to a toxicology panel, I'd probably get massacred. But I'm going to endocrinology panels and the response over here by a person who obviously studies hormones and understands them is the typical response of anybody in endocrinology, which is- “Yeah! There is nothing new here.” Other than that this is a chemical in commerce that is associated with disease and we want you to figure out the molecular mechanisms of the disease. We are not challenging any of the basic concepts that you're proposing. Because we learned them in introductory endocrinology.’ So I don't run into that problem. I've been continuously funded to do this. I got my first NIH grant at 76 and have been continuously funded ever since. Never had any trouble.
TERRY COLLINS: The fact that you are giving this lecture all around the world, the fact that you are writing this (inaudible) actually is the only way we can re-sentence the circumstances with the questions you ask, you have a far higher probability that you can do this work (inaudible).
AUDIENCE: A couple of comments. One is that, it is really interesting to hear about the political side because a lot are very similar to the difficulties that scientists had when they were studying the effects of lead, attempting to get lead out of gasoline in 40 years ago. And then I read another comment. You know, when toxicology research is done, typically individuals or animals- a large number or a large population is given an identical dose and then the response is generally a bell-shaped curve. And the idea behind a regulation to define the maximum level is that, if you can have a level that is sufficiently low, the tail of the bell-shaped curve will be below the effects level. But if you're talking about the inverted ‘U’ shape. Then you are really running into problems because you cannot define a dose that’s sufficiently high and safe.
PROF. FRED: You have just nailed why the risk assessment community is hysterical over this issue. Because it really throws out the window. All of the fundamental processes used in chemical risk assessment, it invalidates them and there is a panicked about that and not so much that they can argue about BPA, but it invalidates every risk assessment for every chemical that's ever been done. And that is a scary proposition.
TERRY COLLINS: Do you have a question there?
AUDIENCE: Yeah, there is some good news. My toxicology friends have told me that Bisphenol A has been removed from baby bottles and baby products now. So there is good news on the horizon.
PROF. FRED: The good news is; BPA is finished as a food contact item. I don't have a problem with it being used to make my glasses or to make CDs as long as it's supposed, disposed of properly. But we can't think of BPA being removed from packaging as an ultimate victory. What we need is this concept that we were just talking about that the risk assessment process for all chemicals has to be revised. The whole way we go about thinking about risk and the whole chemical testing paradigm has to be scrapped and we constructed based on 21st-century science, not on the concepts of Paracelsus from the 16th century that the dose makes the poison. And so hopefully BPA will be the tip of the spear that will help do that and I'm very happy to have BPA get out of baby bottles but we can't do this pick. There are 55,000 chemicals in commerce; we can't do this a chemical at a time.
TERRY COLLINS: A question here?
AUDIENCE: Yeah, I am speaking way out of my knowledge area the main question I thought is, you showed the results on (inaudible) of rats. Are the changes so significant that you are actually saying that mutation is expectedly passed on to future generations that you know (inaudible).
PROF. FRED: So everyone was initially taught that during mutagenesis in early embryonic development. There's a global deprogramming so that you start out life as an unprogrammed fertilized zygote and then you have some few imprinted genes from your mother and father, but the great majority of your genes are then programmed due to your environment. There are now data suggesting that these aberrant epigenetic marks that are induced by these chemicals persist through this demethylation, these methyl groups, and these deprogramming processes. These aberrant marks are escaping that and leading to aberrations that become fixed in the genome and are trans-generational. That is still somewhat controversial, but there are now quite a number of studies showing this. So ten years ago I would've said the good news is we get rid of them and in a generation and it's gone.
That is, these may be transgenerational in terms of ripple effect through and maybe a major evolutionary changing event in terms of a very rapid, environmentally induced Lamarckian evolution of events.
AUDIENCE: So that would be(inaudible)
PROF. FRED: Diatrol sebastrol has still only gone to the offspring of the exposed children, who were abnormal. You have to go to the next generation to demonstrate that you are then truly transgenerational, you have to get the F3. That hasn't been done in humans yet but it's clearly a grandchildren effect for the human DES, but that is not explainable through me. There are other explanations besides abnormal imprinting. We have clear evidence for abnormal imprinting in animal studies. That is, it able to go to multiple generations without being lost. And that's a really unfortunate scary set of events.
TERRY COLLINS: Well, one at the back first.
PROF. FRED: So actually they can be used to make synthetic wood and things like that. And seven is a catch. It is not just dyspnoeal but its primarily dyspnoeal. (inaudible)
Well, there is no specific way to deal with it. And since we don’t know what flame it sets when lit fire on it, we don’t have the possibility of burning it and then releasing bromine or bromine by-products. Terry Collins would know a lot more about the dangers of that.
TERRY COLLINS: Yeah, one last question.
PROF. FRED: So I'm working with the Teamsters union right now to set up that study. A good occupational health study in the United States has not been done. A not so great occupational health study was published this about four or five months ago in human reproduction from China. But they provided so little information and the levels were off the charts. They were hundreds of times higher than anything ever seen in the United States, which now these were people working in a factory maybe that's possible but, I would say that's an open question. We need to know if the kind of occupational exposure to steel beams which we know cause men to be infertile working in factories that were making things like DES. These men were infertile. They grew breasts. They had breast cancer. I mean they were a metabolic nightmare. Bisphenol A could potentially do that if there's no protection for these people, but we have no evidence that that's happening because there is-- no studies have been done.
PROF. FRED: So what in this journal, in response to this article that was just published in toxicological sciences. Again twenty-four scientists got together and wrote a letter extremely critical of the Journal as well as the paper basically saying enough of this because this one journal has published the majority of industry studies challenging the health effects of Bisphenol A it's just one industry control Journal doing this you get rid of this journal, there wouldn't be an argument. And so we are a whole bunch of people way beyond twenty-four are in the process now of writing a major commentary in which the issue you just raised is going to be absolutely directly dealt with and say enough of this and we are going to lay out the criteria for good science and say if you don't meet these criteria and you're going to publish something, then people in the regulatory and legal community should just ignore it and it's going to be signed by so many eminent scientists. This can be very difficult for the FDA, EPA or anybody else to ignore it.
TERRY COLLINS: Let us thank Mr. Vom Saal for an extraordinarily interesting lecture.