This Much Is True

Dietary endocrine disruptors such as isoflavones and bisphenol-A have EPA-defined dosage guides (see 11/8 post entitled The Reference Guide for bisphenol-A). This clears up the question of “how much is too much,” and eliminates the need to heed vague, cautionary speculation regarding dietary consumption of endocrine disruptors.

The other major concern put forth in the essay ”Paralysis Through Analysis” is whether environmental endocrine disruptors have a significant effect on human and wildlife health. This has been explored over the course of this weblog through examination of propaganda websites and facts regarding specific environmental endocrine disruptors. The main concern in this arena is the effect of pesticide treatment and runoff on wildlife and human health. For this reason, the Pesticide Action Network’s wealth of resources regarding environmental endocrine disruption provide excellent answers.

This poster previously wrote regarding the impartiality, reputability, and usefulness of the Pesticide Action Network’s fact sheets. These qualities do not automatically extend to all parts of the PAN web site, and indeed, the specific Endocrine Disruptors page has its strengths and weaknesses. It is slightly less accessible than the pesticide fact sheets, presenting solid examples and proof, but not always including the conclusion drawn from that research. This allows the reader to jump to erroneous conclusions more easily than when the statements of the writer are stated explicitly, as in the fact sheets. It errs on the side of professing the danger of endocrine disruptors, and indeed is aimed at spurring readers into action about monitoring endocrine disruptors.

However, the one conclusion that seems positively natural and necessary after reading this page is this: more research is needed regarding the effects of environmental endocrine disruptors, including pesticides. Through this weblog’s six weeks of examining the topic, this need for more research has continued to present itself in the form of bickering propaganda citing half-truths, as well as well-supported articles that tend to say “well, we don’t really know, but here is what the evidence suggests.” In closing, the BCA Advanced Chemistry Paralysis Through Analysis weblog summates with this quote from the PAN Endocrine Disruptor Page:

“Data on the health effects on humans of environmental [estrogens] is fragmentary, but suggestive and worrisome.”

The suggestions of the previous research, and the fragmentary nature thereof, make an excellent basis for more research. They do not provide a sound basis for the unsubstantiated, extrapolated conclusions often abounding on the internet: logical, alarmist, or otherwise.

Bisphenol-A in Dental Sealants

After bottled water, dental sealants are the most common case of rumored bisphenol-A exposure. They are made mostly of a monomer called bisphenol-A glycidyl methacrylate, or bis-GMA, along with bisphenol-A dimethacrylate (bis-DMA), ethylene glycol dimethacrylate (EGDMA) and triethylene glycol dimethacrylate (TEGDMA). While many of these polymers contain bisphenol-A, it is important to note that bisphenol-A itself is not used in dental sealants.

The fear of bisphenol-A exposure from dental sealants was started by a study conducted by Nicolas Olea in 1996 at the University of Granada and Tufts University. Olea found that an hour after applying a variety of commercial dental sealants, the saliva of his test subjects contained between 90 and 931µg of bisphenol-A. Considering that the Reference Dose for BPA is only 50µg, the experiment appeared to raise a grave and legitimate concern.

However, this experiment has not been replicated with the same results. Two groups have attempted experiments using the same sealants, but recorded levels of BPA 10 and 250 times lower than those found by Olea. Additionally, both found that after 24 hours, there was no measurable amount of BPA in the blood and saliva of the subjects.

While the disparities between the results may appear irreconcilable, there are reasonable explanations. Many suggest that the equipment Olea used might have confused triethylene glycol dimethacrylate (TEGDMA) with bisphenol-A. Additionally, Olea used excessively large amounts of sealant, which might have caused leaching.While there is some risk of bisphenol-a exposure attributed to dental sealants, it is essentially negligible, as it does not come near the RfD value established by the EPA.

The Reference Dose for Bisphenol-A

Although a number of groups state otherwise, there is only one generally accepted guideline regarding safe bisphenol-a exposure - the Reference Dose for Chronic Oral Exposure (RfD) as established by the EPA. In short, the reference dose is the amount of a chemical a person can take in on a daily basis without it having any harmful effects, measured in milligram of substance per kilogram of body mass per day. The recommended dose for bisphenol-a is 0.05 mg/kg/day.

The reference doses for all chemicals are determined experimentally. To find the RfD for bisphenol-a, scientists fed animals varying amounts of the chemical to see at what point they could observe adverse effects. This point, known as the Lowest Observed Adverse Effect Level (LOAEL), was established to be 50 mg/kg/day in rats, at which point the F1 (second) generation became underweight, and 130 mg/kg/day in mice, at which point the scientists found an increased number of multinucleated giant hepatocytes (abnormal liver cells). Tests were also conducted on dogs, but no serious adverse effects were found.

With this information, the EPA determined the RfD of bisphenol-a to be 0.05 mg/kg/day. Despite the varying LOAEL’s, the EPA is confident in its results. It feels that its investigation was sufficiently complete and that there is little reason to believe that the RfD should be lower. Therefore, the consumer should have confidence that any government-approved products containing bisphenol-a are safe for regular usage.

A Truthful, Balanced Website

There exists at least one truthful website regarding synthetic endocrine-disrupting toxins in the environment. It is called the Pesticide Action Network UK, or PAN UK.

PAN UK has a database of pesticide fact sheets, including discontinued and currently monitored pesticides. Each pesticide fact sheet is written simply, and is easily understood and accessible. All information is cited to reputable references, and each article has a lengthy list of diverse sources (usually at least 15 sources per fact sheet, sometimes as many as 30).

This fact sheet on the commercial fungicide chemical Vinclozolin, for instance, cites government- and university-funded studies regarding the possible endocrine-disrupting properties of the fungicide. It chronicles the history of monitoring the chemical, including what decisions were made regarding its safety and what investigations are still underway. The Vinclozolin fact sheet delineates between acute and chronic toxicity risks, and specifically addresses each health concern. In the “Chronic Toxicity” section, it addresses the important question of whether Vinclozolin is an endocrine disruptor, and how much bearing the tests on animals may have on effects of Vinclozolin on humans:

The [EU’s Scientific Committee on Plants] said humans were not more sensitive than animals, and that it was unlikely that a single exposure could cause ill effects… It did however, note that adverse effects on young animals were generally irreversible, whereas effects on adult animals could generally be reversed. It is likely that as a result the UK ACP will now consider restoring the currently suspended approvals.
In the meantime, the US EPA considers vinclozolin to be an endocrine-disrupting chemical interfering with lipid metabolism and/or storage and inducing reduced sperm count, decreased prostate weight and delayed puberty in test animals.

This website publishes clear, balanced, accessible facts based on good research of well-founded university and government studies. It is a rare, refreshing gem of a webpage. Though not as titillating or alarming as many of the previously posted propaganda websites on this blog (such as the Soy Online Source and Our Stolen Future), this website is certainly much more exciting .

Won't Someone Tell Us the Truth?

Andrei Sakharov once wrote, “intellectual freedom is essential to human society -- freedom to obtain and distribute information, freedom for open-minded and unfearing debate and freedom from pressure by officialdom and prejudices. Such a trinity of freedom of thought is the only guarantee against an infection of people by mass myths, which, in the hands of treacherous hypocrites and demagogues, can be transformed into bloody dictatorship.” Unlike Sakharov, we currently live in a non-dictatorial state that does not oppress its people. Yet, society continues to suffer mass myths at the public level which affect everyday lives.

For example, in 1998, the Natural Resources Defense Council, an organization that works to “ensure a safe and healthy environment for all living things” published on its website the following statement on the exposure of endocrine disruptors in the mass market:

“The majority of the more than 2,000 chemicals that come onto the market every year do not go through even the simplest tests to determine toxicity. Even when some tests are carried out, they do not assess whether or not a chemical has endocrine interfering properties.”

Our scientific community has proven this to be verifiably false. The FDA carries out four phases of studies and tests to determine the toxicity of products on the mass market. Study after study, it has been proven that risks of endocrine disruptors in plastics and other everyday items are non-existent. Yet, this “nationally-renowned” organization strives to confuse the public and create panic. They will argue that it is a simple fact of intellectual freedom: they are allowed to say whatever they want to say.

The question herein lies: where does intellectual freedom stop and verified evidence begin? Certainly, intellectual freedom has gone excessively far in the controversy over endocrine disruptors on the mass market. Won’t someone simply tell us the truth?

Dr. vom Saal's Shocking Allegations

The notorious Bisphenol A critic, Dr. Frederick vom Saal, revealed study results on his website for 125 studies conducted on the low dose effects of Bisphenol A. Of those 125 studies, 114 of them were funded by the government and 91.2% of those presented harmful effects. The remaining 11 were funded by the chemical industry, of which 0% found harmful effects.

However, the most alarming evidence that he presented was a 1938 article in the Lancet by Nobel Prize laureate, Sir Charles Dodds, which outlined his discovery of the estrogenic effects of DES (which led to its mass production for pregnancy treatments). Apparently, Dodds discovered that DES was even more powerful than a newly discovered estrogenic chemical called Bisphenol A. Therefore, Bisphenol A was never used as a drug, and instead was mass manufactured as a monomer to make plastics and cans. Vom Saal wrote:

"Sir Charles Dodds received the Nobel prize for discovering the extremely potent estrogenic drug diethylstilbestrol (DES) in 1938, which was more powerful than any of the estrogenic chemicals, including bisphenol A, examined in this 1936 article. Bisphenol A was thus never used as a drug, and, instead, in 1957 bisphenol A was used as the monomer to make polycarbonate plastic and resins used to line cans."

In effect, Vom Saal is saying that the plastics industry totally ignored the fact that Bisphenol A is an estrogenic compound on the sole basis that DES was stronger. That's like saying that Big Macs should become a staple in diet menus simply because triple layered fudge cakes are more fatty. If this is true, vom Saal might be on to something. The missing link, however, lies in the original evidence of the estrogenic effects of Bisphenol A before 1938. If Dodds was referencing this evidence--where is it? It seems that Vom Saal hasn't found it yet.

Endocrine Disruptors and Gender Ratios

In October of 2005, a group of scientists published a journal article about an Aamjiwnaang First Nation (Native American) community in Ontario. The community is located near an industrial center and in recent years has been encountering very disturbing sex ratios. In the past ten years, 41.2% of all births have been male children and in the past five years, this number has decreased to 34.8%. The scientists’ study set out to find if endocrine disrupting materials produced in the industrial plants were influencing the sex ratios.

The study included surveys, environmental analysis and both a Canadian and First Nation control group. In the end, the data collected revealed that the sex ration of the community had remained relatively constant until 1993, at which point it began to fall at a steady rate.

While it is certainly possible that these results were caused by other factors, such as nutrition, parental age, and illness, endocrine disruptors appear to be a reasonable cause for the sudden change in the community’s sex ratio. Though the sex of the fetus is determined at conception, parental hormone levels have been determined to be partially responsible for determining the birth ratio. Because endocrine disrupting chemicals can “mimic” hormones, they can have the same effect as naturally occurring chemicals. More importantly, the study found that the area of the community had been known to contain EDC contamination:

“Numerous studies indicate that wildlife populations in the Great Lakes area are being adversely affected by the level of contamination, and that evidence from wildlife research could be used as a sentinel for human health effects (Fox 2001). In the Great Lakes area close to the Aamjiwnaang reserve, fish with intersex gonads (both male and female) have been reported in Lake St. Clair (Kavanagh et al. 2004). There is also ongoing research in the St. Clair River Area of Concern region of the Great Lakes that is documenting reduced hatching success and altered sexual development in turtles as well as changes in the sex ratios of birds (Environment Canada Canadian Wildlife Service 2003)”.

If the only condition that caused the gender ration of the Aamjiwnaang to change so dramatically was industrial waste, other industrial towns may soon face similar problems. Though it is impossible to pinpoint the issue to Endocrine Disrupting Chemicals, the possibility that they may be responsible does constitute a cause for concern. While more studies must still be conducted to prove this theory, action ought to be taken to clean up industrial communities, not only because of their risk of EDC exposure, but also because of the general health hazards they pose.

DES is Not an Estrogenic Compound

Dr. Schwarcz begins his discussion of endocrine disruptors in “Paralysis Through Analysis” with a mention of alligator penis length. Dr. Schwarcz mentions a study on the alligators in polluted Lake Apopka in Florida. The alligators in Lake Apopka had penises 24% smaller than the penises of alligators in a nearby, cleaner lake. An abundance of a testosterone-blocking chemical, that accounted for the difference in length.

The authors of this study very carefully denoted what could and could not be deduced from the findings. Like Dr. Schwarcz, they do not claim universality, and draw a line between alligators and mice, and mice and humans. No claims are made about a non-studied relationship. All references are cited. While seemingly elementary, these qualities do a significant service to the reader by insuring reputability. This is a reputable article on a focused study.

One section of this article discusses a point glossed over by all DES-related articles previously mentioned in this weblog:

The underlying cause of these abnormalities, as well as the reported developmental problems in females, has been hypothesized to be due to "estrogenic" contaminants…Although DDT has been reported to be estrogenic…a controversy exists as to whether p,p'-DDE is estrogenic or not …However…p,p'-DDE binds the androgen receptor preferentially compared to the estrogen receptor and acts in the yeast system as an antiandrogen.

This has huge implications regarding articles claiming that DES is estrogenic. True, it is an endocrine disruptor. But there is no cited evidence in any articles mentioned in the weblog to show that antiandrogens are responsible for the same effects as estrogenic compounds (including possible increased risk of breast cancer and thyroid activity disruption).

This is further proof that the inflammatory articles on the internet must be checked and re-checked against reputable scientific findings. Examining each claim closely against articles such as this reveals holes and hand-waving on the part of the propagandists on both sides.

The Dark History of Synthetic Estrogens: DES

Between 1938 and 1971, four million pregnant women were prescribed Diethylstilbestrol, a ‘miracle’ drug that was said to improve chances for a healthy and successful delivery. However, Diethylstilbestrol (DES) proved to become the horror for at least three generations of women, and will continue to haunt generations to come with adverse health effects.

In 1971, the U.S. Food and Drug Administration announced the link between DES consumption and the development of clear cell adenocarcinoma of the vagina and cervix and an increased risk of breast cancer in the daughters of those who consumed the drug. In later studies, it was shown that the sons of those who consumed DES developed an increased risk of testicular and prostate cancer. Additionally, it was discovered that those who were exposed to DES have a higher rate of preterm deliveries and second trimester spontaneous abortions. According to a 1997 study, published in The American Family Physician, even generations as far back as grandchildren can exhibit effects such as an increase in reproductive tract tumors.

Perhaps it is the story of DES that drives the studies and conclusions of Bisphenol-A critic, Dr. Frederick vom Saal. The scientific community persistently advocated the safety of DES for nearly 35 years. Similarly, much of the scientific community currently denies any significant link between average human exposure to Bisphenol-A and estrogenic effects. Perhaps the story of DES teaches us this: never doubt the critic.

Response to “Does Bisphenol-A Cause Miscarriages?”

At around the same time that the Guardian reported on a Japanese study liking Bisphenol-A to miscarriages, ourstolenfuture.org, a website devoted to exposing the perceived evils of Bisphenol-A, did a similar report. While the website has very clear motives and views, its report on the study was fairly impartial. In fact, Our Stolen Future gave more facts about the study than did the Guardian.

While one might have expected ourstolenfuture.org’s analysis of the article to interpret the results of the experiment as definitive evidence for their cause, the website took a more resigned approach. The article acknowledged the small sample size of the experiment and that the results may have been incorrect. At the same time, it tried to discount this by using the results of experiments conducted on animals as evidence for the dangers of BPA. However, within their rigidly dogmatic theories, the ourstolenfuture.org made a very valid point:

“The possibility that BPA may be a cause of some percentage of these abortions opens the possibility that some cases of spontaneous abortion may be preventable through exposure reduction.”

Even if there is no solid, conclusive scientific evidence that Bisphenol-A is dangerous to the population of the world, perhaps governments should try to limit its use because the consequences would be too great if it actually were dangerous. Maybe the United States should impose EU-like regulations, which acknowledge the possible risk of Bisphenol-A without doing too much damage to businesses. The truth of the matter is that in the end, the most important concern should not be who is more correct, but the outcome with relation to human lives.

Synthetic Endocrine Disruptors Estriol, DDT, and DES Inspire Propaganda

This weblog has so far explored the validity of claims that exposure to bisphenol-A and isoflavones is harmful to humans. In his essay, “Paralysis Through Analysis,” Dr. Joe Schwarcz mentions synthetic estrogenic compounds other than bisphenol-A, such as DDT, DDE (a biproduct of DDT decomposition), and DES. Perhaps a better idea of the climate surrounding endocrine disruptors can be gained by looking at the public internet reaction to these chemicals as well.

A Google search with search terms DDT and DDE shows that the inflammatory, relatively unsubstantiated writings about endocrine disruptors are not limited to bisphenol-A and soy. The first page linked to on that search, entitled Estriol, DES, DDT written by Ray Peat makes broad cautionary claims about Estriol, DDT, and DES, as well as hormone replacement therapy for menopausal women and dietary estrogenic exposure.

This webpage is a work of manipulated fact to the point of science fiction. Mr. Peat’s claims are not even loosely based on the sparing quotes he uses from scientific journals; it would be kind to say that his claims are even inspired by the quotes. In one example, Mr. Peat uses the fact that “weak” estrogenic compounds in the environment become much stronger through synergistic reactions (which is a cited example from the journal Science in 1996) to draw the conclusion that exposure to different types of estrogen are “almost certain to have unexpected results.” This is simply a provocative, fear-inducing method of saying that no one has significantly studied this possibility and that it frightens the author. "Almost certain" of "unexpected results" means "I don't know what is going to happen."

Mr. Peat also makes claims which he does not even pretend to prove or support. For instance, he claims that hormone replacement therapy is upsetting because it is “administered in quantities much larger than [menopausal women’s] bodies ever produced metabolically.” Regardless of whether this is true, Mr. Peat gives no indication that that quantity of estrogen is dangerous to these women. Once again, it alarms him, and he alarms his readers.

The unsubstantiated claims on this webpage are too numerous to name individually.

This is not science writing: it is broad, uninformed speculation made to prey on fears and encourage distrust of the scientific and medical communities. There are reasons for caution and inquiry with respect to these institutions, but not on account of this article. Unsubstantiated arguments are mentioned offhand with vague, cautionary language and faulty reasoning. No complete arguments are made, and reasoning is secondary to shock value. Hopefully, pages like this succeeds in causing skepticism and distrust toward the author, and readers judiciously continue research in more reputable places. Sadly, as indicated by the popularity of this web site (Google presents pages in the order of most-linked to least-linked on that topic), that is not likely to be the case.

Does Bisphenol-A Cause Miscarriages?

On June 11th, the Guardian reported on a startling Japanese study that links miscarriages and high levels of Bisphenol-A in the blood. The study examined 45 women who had three or more miscarriages and 32 women who had not had any. They found that the women with multiple miscarriages had, on average, three times more Bisphenol-A in their blood. Additionally, 17 out of 35 of the women who became pregnant during the study suffered miscarriages. Of these, four of the stillborn fetuses had the wrong number of chromosomes.

The article goes on to praise the significance of the study, quoting the scientist who made the discovery and a representative from the World Wildlife Fund. Elizabeth Salter-Green of WWF-UK had this to say:

"This study shows the importance of taking action to eliminate exposure to endocrine-disrupting chemicals such as bisphenol-A. WWF would like to see a ban on the use of bisphenol-A in food packaging, baby bottles and in any other product where it will be a source of human and wildlife exposure."

However, not everyone agrees. Alan Boobis of the Imperial College London, a member of the Food Standards Agency of the United Kingdom, believes that the study is too small to produce conclusive evidence and that the results found are only a “hypothesis”. He is not alone; Bisphenal-a.org, a website run by the plastic companies, claims that a similar article published in Current Biology did not follow international standards in their work, thereby nullifying the results. They additionally stated that the study used quantities of Bisphenol-A that were much higher than any consumer could accumulate in their body. Though there seem to be a number of studies proving the connection between Bisphenol-A and miscarriages, Mr. Boobis and the plastic companies do have a point: One cannot trust evidence based on faulty methods.

EPA Weighs in on Low-Dose Theory

In August of 2001, the EPA’s division of the National Toxicology Program hosted a conference in Research Triangle Park in North Carolina to put the best minds in the endocrine-studies community together to figuratively decide the merits of the proposed low-dose theory.

Once again, the low dose theory claims that hormonal side effects of Bisphenol A could occur at exposure doses much less than 5 ppb, the current screening level by the FDA.

Dr. Frederick vom Saal, alongside scientists from the plastics industry, were invited to share their studies and professional viewpoints on the subject matter. The panel of scientists and experts were asked to evaluate the empirical evidence of demonstrating low-dose effects of Bisphenol A on the reproductive and endocrine systems, the evidence demonstrating the lack of low-dose effects, the analysis of biological structures of Bisphenol A and identified natural endocrine disruptors, each studies’ use of a variable chemical in experiments (to identify technique errors), and to identify gaps in research that could help with additional studies of the low dose theory.

The panel, however, concluded that there is insufficient evidence that Bisphenol A can produce endocrine disruptive effects at normal daily consumption:

“There is credible evidence that low doses of BPA can cause effects on specific endpoints. However, due to the inability of other credible studies in several different laboratories to observe low dose effects of BPA, and the consistency of these negative studies, the Subpanel is not persuaded that a low dose effect of BPA has been conclusively established as a general or reproducible finding. In addition, for those studies in which low dose effects have been observed, the mechanism(s) is uncertain (i.e., hormone related or otherwise) and the biological relevance is unclear.”

However, after the NPT’s report was published later that year, vom Saal went right on back to his lab and continued research on the hormonal effects of Bisphenol A, causing added worries and panic in the public that not everything was settled. The scientific community had already weighed in on the issue and claimed that vom Saal’s theory was ‘not credible’. Vom Saal wouldn’t listen. The question is: are his actions stubborn or simply persistent?

Article Cites "Proof" For Questionable Conclusions

Countless websites point their readers towards studies showing that isoflavones (a phytoestrogenic protein in soy) can act like estrogen, or that “too much” soy is unhealthy. Unfortunately, it is far more difficult to find an article specifically giving information about what quantity of soy is safe to consume. The Soy Online Service, a commonly linked website for articles on the dangers of soy, has a Doses Simplified page, which purports to do so, but serves only to create fear.

For instance, on the Doses Simplified page, under the heading “Adults,” the Service states that “A glass a day melts the thyroid away.” It goes on to cite a women’s magazine article stating that “as little as 30mg a day of soy isoflavones have been proven to suppress thyroid function.” Between the catchy and frightening manipulation of a familiar adage and the quotation of a seemingly reputable article, this passage quickly and effectively causes fear. Influenced by this warning, a consumer is unlikely to ask whether the “proven suppression of thyroid function” is harmful. That is exactly what the reader deserves to know. The simple fact that a substance somehow affects a chemical process in the body should not cause alarm. To some degree, that is how metabolism of most food works. Thus, stating that isoflavones suppress thyroid function without stating to what degree, or whether this suppression is harmful, is irresponsible. The image of one’s thyroid melting away is indeed an alarming prospect. The reader is led to believe, partially influenced by the headline, that a certain quantity of soy is dangerous because it affects a bodily system at all.

Under the heading “Women,” the dosage guide resorts to a different tactic: taking one finding in a scientific study completely out of context. It states that “Disruption of the Menstrual Cycle ( a harbinger of potential fertility problems) was caused by 45mg/day for only 30 days…Irregular cycles are also a risk factor for breast cancer.” The article links to an abstract that does indeed state that 45 mg/day of isoflavones disrupted the menstrual cycles of six women. It did not, however, link these changes in menstruation to the same types of menstrual changes that act as a risk factor for breast cancer. Furthermore, nowhere does the abstract of the study state that the changes of menstrual regularity were in any way linked to “fertility problems.” The dosage guide extrapolates beyond reason to the point of lying.

So what does the abstract of this scientific study say about the effects of soy on breast cancer risk? One needs only to look at the abstract’s conclusion to see the sentence, “The responses to soy protein are potentially beneficial with respect to risk factors for breast cancer and may in part explain the low incidence of breast cancer and its correlation with a high soy intake in Japanese and Chinese women.”

E.U. Puts Higher Standards on Endocrine Disruptors

In October of 2004, the European Commission adopted a new system named REACH for the regulation of potentially harmful chemicals, including believed endocrine disruptors, within the EU. While this may seem like a dismissible occurrence, a number of environmental and health organizations have praised it, including the World Wildlife Fund, which claims that REACH represents “a big step towards better chemicals policy…by requiring adequate scientific data as a precondition for selling chemicals - or products containing chemical”

REACH takes a completely different view on endocrine disruptors. While governments typically do not strictly regulate chemicals until they have been proven to be harmful, REACH balances the need to use chemicals with the need to protect the health of the consumer, as seen in the WWF’s description of the new conditions by which companies can get their chemicals authorized:

“The regulator will prioritize the chemicals of very high concern [including endocrine disruptors] selecting those that will enter authorization first. For such chemicals, companies will be told that they must apply to the regulator for an authorization if they wish to continue using the chemical. They must justify their use by either showing that the use will be ‘adequately controlled’, or if this is not possible, that the use is justified by a socioeconomic assessment, taking into account safer alternatives (though the text states that the existence of safer alternatives is not sufficient reason to refuse an authorization).”

It would appear as though the system employed by REACH should serve as a model for chemical policy in other countries, as it does not outwardly ban chemicals that might prove dangerous. Rather, it requires that they be monitored to secure general safety within reasonable standards. Especially when considering endocrine disruptors, about which there is so much debate, REACH seems to mollify the fearful without employing unnecessary precaution.

The entirety of REACH may be found here

What if vom Saal is right?

Dr. Fred vom Saal is not crazy, nor is he a fraud. It is vital that every critic come to realize this when scrutinizing his work. He certainly is not a Kevin Trudeau. He is a professor of reproductive biology at the University of Missouri and holds several degrees from New York University and Rutgers University. Therefore, although many people might disagree with his work, it certainly deserves a thorough review and analysis.

Recently, Dr. Fred vom Saal published an article in the Environmental Health Perspectives Journal of the National Institutes of Health- An Extensive New Literature Concerning Low-Dose Effects of Bisphenol A Shows the Need for a New Risk Assessment. In it, he refutes the findings by the Harvard Center for Risk Analysis by claiming that significant new medical literature points to the effects of Bisphenol A as an estrogen-like compound:

Of a total of 115 published studies with low doses of BPA below the prior LOAEL of 50 mg/kg/day that we accessed via a PubMed search at the end of December 2004, there have been 94 published studies reporting invivo estrogenic activity of BPA. Of the 94 low-dose studies reporting significant effects, 31 published studies have reported effects caused by doses of BPA at and below the reference dose of 50 µg/kg/day.

Rate of growth and sexual maturation, hormone levels in blood, reproductive organ function, fertility, immune function, enzyme activity, brain structure, brain chemistry, and behavior are all affected by exposure to low doses of BPA. Many of these effects are due to exposure during early development (gestation and/or lactation), but effects due to postweaning-through-adult exposure have also been reported.

Furthermore, Dr. vom Saal asserts that the recent study by the Harvard Center for Risk Analysis were funded and sponsored by the American Plastics Council and that the findings deliberately picked 19 of the 47 available studies to scrutinize, the majority of them being industry-sponsored studies.

It is critical for the medical and scientific community to carry out its studies in an objective and impartial manner. The issues at hand affect everyone. What if Bisphenol A turns out to be harmful? What if it causes hormone disruption? Even worse, what if BPA turns out to act as a carcinogen? If one contingent of the medical community argues that BPA is harmful and the other asserts that it is absolutely safe at all levels—who should the average citizen trust?

Article Warns that Soy is a Dangerous Phytoestrogen

The average consumer can’t help being unsure about the effects of low-dose synthetic endocrine disruptors. Professors, research scientists, governments, and industries have evidence to clearly support both sides of the debate, and the only way to thoroughly evaluate the validity of their claims is to look at the techniques and approaches of the studies themselves. Most Americans do not have the time, interest, or education necessary to do so. Even the experts can’t agree.

Dr. Schwarcz mentions in "Paralysis Through Analysis" that only 0.001% of all estrogenic compounds are synthetic, and asks: if we’re worried about endocrine disruptors at all, shouldn’t we worry about the 99.9% of them that are non-synthetic? People can’t completely avoid ingestion of and exposure to endocrine disruptors, but maybe it would be prudent to cut down on the major sources of dietary endocrine disruption, including soy. Soy is a phytoestrogen, and the medical community (as well as a large number of alarmists looking to turn a profit) has made clear the possibility that it may be linked to an increased risk of breast cancer, modified fertility, and thyroid problems (including hypothyroid difficulties and even thyroid cancer).

In a report on the “The Dangerous Downside of Soy Products,” focuses on the dangers of soy infant formulas. Citing the Soy Online Service, the article claims that “for infants, any soy is too much.” This ignores the fact that for many infants, breast milk and non-soy formulas are not a healthful option because the infants cannot process milk proteins or elements of other milk-alternative formulas. The risks must be weighed against the benefits. In general, “The Dangerous Downside of Soy Products” is a fair treatment of the topic. It warns against adults “consuming huge amounts of soyfoods for their putative disease-prevention value,” but not against consumption of any soyfoods at all. It points to quantitative assessment of how much soy is contained in 128 common soyfoods. The emphasis on moderation and responsible encouragement of moderation and dialogue with one’s physician to assess individual risk factors make this site far less inflammatory than some.

Some of the language in this article is accusatory and unreasonably conspiratorial. The article claims that soy is not more well-known as a cause of health problems because “of the tremendous strength of the large agricultural companies that dominate America’s soy market.” While this language tends to be balanced by responsible recommendations, it still marks a trend of distrust and accusations toward the medical and industrial community. While indicating the USDA as the place to find soy content reports, it directs the reader to the Soy Online Service to find out "how much soy is too much." Articles warning about health dangers of endocrine disruptors should come with a disclaimer: May appeal to fears and induce emotion-based thinking.

Harvard Study Slams vom Saal’s Assumptions

According to a Harvard Center for Risk Analysis study published in 2004, Weight of the Evidence Evaluation of Low-Dose Reproductive and Developmental Effects of Bisphenol A, there is no ‘consistent affirmative evidence’ of low-dose Bisphenol A effects on the human hormonal system. This directly refutes Dr. Fred vom Saal’s “low-dose” speculations.

The low-dose theory states that Bisphenol A, at very low amounts (below the screening capabilities by the FDA of 5 ppb) can act as an artificial estrogen, thereby disrupting the endocrine (hormonal) system and possibly acting as a carcinogen.

Fed up with inflammatory speculations, scientists at the Harvard Center for Risk Analysis put this “theory” to the test. A panel headed by Donald Mattison investigated and compared 19 different animal studies to determine the effects of low-dose Bisphenol A exposure. Using criteria including universality (whether an effect is found throughout all species and experiments), proximity (the effects in species closer to humans / similar routes of exposure), and plausibility (the possibility of shared characteristics by Bisphenol A and estrogenic compounds), the panel concluded:

“The panel’s review of the literature indicated that BPA does not exhibit several key characteristics that are typical of estrogenic agents. For example, natural estrogen causes cancer at high doses, whereas BPA does not. The panel concluded that because BPA does not share these other well-established estrogenic characteristics, it is unlikely to be exhibiting estrogenic characteristics in the case of the disputed impacts on the male reproductive tract.”

How long will it be until a desperate Dr. vom Saal questions the credibility of Harvard’s conclusions?

How would you like your endocrine disruptors, natural or artificial?

In The Fly in the Ointment, Dr. Joe Schwarcz writes regarding human exposure to natural estrogen-like compounds in day-to-day life. He states that the presence of these compounds should negate all arguments that synthetic endocrine disrupters can be overtly harmful because only 0.001% of all estrogenic compounds are synthetic. However, not everyone shares his views. The writers of Our Stolen Future, a book that warns about the dangers of endocrine disrupters, differ in opinion. In an article published on their website, the authors explain their doubts:

"Their argument fails on several grounds. First, it fails because much, but not all, of the exposure to synthetic hormone disruptors is not dietary. Their argument is irrelevant to non-dietary exposures. Second, it fails because it completely ignores the fact that many hormone disruptors interfere with hormones other than estrogen."

As I see it, this rebuttal has more faults than Dr. Schwarcz's argument. To address their first concern, it is totally contradictory to say that synthetic endocrine disruptors are not absorbed through dietary exposure. One of the key arguments used by those who are worried about synthetic endocrine disruptors is that compounds found in plastics can be leaked through plastic water bottles and milk bottles. To say that this is not dietary consumption is absolutely preposterous.

The second argument, on the other hand, would seem perfectly logical, if it weren’t for the figure Dr. Schwarcz mentioned of 0.001% of all endocrine disruptors being synthetic. Even if only 1% of natural endocrine disruptors interfered with estrogen, they would still be 1000 times more numerous than synthetic endocrine disruptors. Clearly, Schwarcz is not the one with the flawed argument.

Japanese Study Seems to Refute Exposure-Level Claims

“Paralysis Through Analysis” presents the argument over whether everyday exposure to endocrine disruptors (such as DES, DDT, DDE, and bisphenol-A) is significantly dangerous. The plastics industry adamantly refutes claims of adverse effects of bisphenol-A at any level of exposure. They also deny detectable leeching of bisphenol-A from plastic products. Dr. Fred vom Saal spearheads the “other side” of the debate. He claims that quantities of bisphenol-A so small that they “defy laboratory detection can still cause an effect in animals” (page 49 of The Fly in the Ointment). Dr. vom Saal also claims that large doses (such as some of those used by the plastics industry to test effects of bisphenol-A) do not have adverse effects because in toxicology, proportional doses do not necessarily produce proportional results.

This is commonly accepted knowledge. Dr. vom Saal maintains that “a tiny dose in the fetus could cause effects unseen in adults given even higher doses” (page 48), a statement supported by the effects of Fetal Alcohol Syndrome when compared to the effects of adult alcoholism. This does not categorically prove that dose is not proportional to effect, but it does support the notion of such a trend.

This would seem to be convincing support for Dr. vom Saal’s assertions. Unfortunately for his theory, there is evidence that doses far higher than those he tested can disrupt endocrine function. Not being a toxicologist, I can only raise a question: is the toxicity per dose a single-peaked distribution? If so, according to an experiment done at Kamakura Women’s College in Japan (link to study), the peak in animal response occurs at a far higher dose than Dr. vom Saal asserts.

After administering 1 ppm of bisphenol-A to one group of rats and 100 ppm to another group, the researchers found endocrine disruption in one group only: the group treated with 100ppm of bisphenol-A. The effects are described in this section of the abstract:

General edema and swelling were found in all embryos treated with
bisphenol A at the concentration of 100 ppm… In regard to animals treated
with bisphenol A at a concentration of 1 ppm, no histological changes were found.
In conclusion, we considered that bisphenol A markedly produced general
histological changes at the concentration of 100 ppm, but not at
the concentration of 1 ppm.

Laboratory equipment can detect bisphenol-A at levels of 5 parts per billion. It is possible, though seemingly unlikely, that there is a zone (from levels less than 5 ppb to at least 1 pmm) in which the chemical does not affect endocrine function whatsoever, and that levels above or below this huge range are toxic. It is possible that this is a dual-peaked distribution. It is also possible that Dr. vom Saal is wrong. This study makes both possibilities worth consideration.

This study also brings into serious question the bisphenol-A producers' claim that the chemical is non-toxic in animals at doses "both higher and lower" than doses in Dr. Patricia Hunt's study. It would seem that neither vom Saal nor the plastic industry has a theory that withstands strict scrutiny.