Hormone disruptors are regenerating themselves in darkness / casting doubt on environmental risk assessments

Hormone disruptors rise from the dead

Broken-down pollutants reform in the dark, casting doubt on environmental risk assessments.

26 September 2013
The vast amounts of steroids that are fed to cattle in some countries end up in farm run-off and may affect the environment even after they are broken down by sunlight.

Melanie Blanding/Alamy

Hormone-disrupting chemicals may be far more prevalent in lakes and rivers than previously thought. Environmental scientists have discovered that although these compounds are often broken down by sunlight, they can regenerate at night, returning to life like zombies.

“The assumption is that if it’s gone, we don’t have to worry about it,” says environmental engineer Edward Kolodziej of the University of Nevada in Reno, joint leader of the study. “But we’re under-predicting their environmental persistence.”

“Risk assessments have been built on the basis that light exposure is enough to break down these products,” adds Laura Vandenberg, an endocrinologist at the University of Massachusetts in Amherst who was not involved in the study. “This work undermines that idea completely.”

Endocrine disruptors — pollutants that unbalance hormone systems — are known to harm fish, and there is growing evidence linking them to health problems in humans, including infertility and various cancers1. But pinpointing specific culprits from the vast array of trace chemicals in the environment has proved difficult. Indeed, concentrations of known endocrine disruptors in rivers often seem to be too low to explain harmful effects in aquatic wildlife, says Kolodziej.

Beefed up

He and his colleague David Cwiertny, an environmental engineer at the University of Iowa in Iowa City, decided to find out whether the breakdown products of endocrine disruptors could be boosting their environmental impact. Their team focused on trenbolone acetate, a synthetic anabolic steroid used as a growth promoter in more than 20 million cattle in the United States each year (this practice is banned in the European Union).

Cattle metabolize the steroid into compounds such as 17α-trenbolone, a potent endocrine disrupter commonly found in agricultural run-off water. In laboratory tests, just a few tens of nanograms of these compounds per litre can skew sex ratios and decrease fertility in fish2, 3. Some manufacturers have argued that these metabolites pose little risk in rivers, however, because sunlight breaks them down rapidly.

Kolodziej and his team put solutions of 17α-trenbolone and related compounds through several cycles of light and dark in the laboratory. Although concentrations fell during the simulated daytime, the scientists were surprised to see that levels rebounded during the dark periods. At neutral pH and 25 ºC, it took about five days to regenerate 60% of a sample of 17α-trenbolone from its breakdown products. Higher temperatures or slightly acidic or alkaline conditions accelerated this process.

“I’ve never seen anything like it,” says Vandenberg. Field biologists usually collect water samples during the day, she says, and nocturnal regeneration “would certainly have the potential to impact those results.” Moreover, field studies have rarely reported the pH and temperature of water samples, which could have a big effect on true concentrations of contaminants. “I don’t think that anyone had conceived it could be so important,” she says.

The team found the same regeneration process occurring in water samples taken from the Iowa River, and from a test pond seeded with manure from cattle that had been treated with trenbolone acetate. They also note that other steroids with similar chemical structures can regenerate in the same way, including dienogest, an oral contraceptive, and dienedione, an illicit anabolic steroid. The results are published in Science4.

Hiding in plain sight

Kolodziej says that the work casts considerable uncertainty over sampling results for steroid endocrine disruptors, and suggests that a survey of their breakdown compounds in the environment is now urgently needed.

It also highlights a serious drawback in relying on studies that look for single environmental contaminants, rather than a spectrum of their derivatives, he adds. Chemical studies should be complemented with bioassays that use living cells to detect endocrine disruptors, Vandenberg adds.

Last year, a bioassay of this kind found androgens in 35% of freshwater samples tested, far more than chemical assays would suggest5. “What you really want to know is if there’s anything in there that can cause biological activity,” says molecular biologist Gordon Hager, at the National Cancer Institute in Bethesda, Maryland, who developed the assay. Yet current environmental monitoring procedures still rely on checking “a list of chemicals, and they only know how to look for one thing at a time”, he says. “It’s a fool’s errand.”

Journal name:
Nature
DOI: doi:10.1038/nature.2013.13831

Health Research Report 29 JUL 2013

Topics:
DHA for Chronic Pain – Annal of Neurology
Vitamins and Minerals as an alternative psychiatric medications – 2013 IFT
Ginkgo Biloba Extract for Effectively treats Vascular Dementia – Neural Regeneration Research V8 N18 2013
BPA – Damages Teeth Enamel  – AJP
BPA- Causes Obesity in Puberty age Girls – PLOS ONE
BPA- Idiopathic Undescended testis ENDO 2013
BPA – Causes Prostate Cancer ENDO 2013
BPA + Chlorine stop cellular communication – Endocrine disruptors online journal

PFC exposure tied to altered thyroid function

Contact: Jenni Glenn Gingery
jgingery@endocrine.org
301-941-0240
The Endocrine Society

Endocrine-disrupting chemicals may increase odds of women developing mild hypothyroidism

Chevy Chase, MD—Exposure to perfluorinated chemicals is linked to changes in thyroid function and may raise the risk of mild hypothyroidism in women, according to a recent study accepted for publication in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).

Perfluorinated chemicals, or PFCs, are compounds used to manufacture fabrics, carpets, paper coatings, cosmetics and a variety of other products. Among humans and wildlife, PFC exposure is widespread, according to the National Institutes of Health’s National Institute of Environmental Health Sciences. Because these chemicals break down very slowly, it takes a long time for PFCs to leave the body.

“Our study is the first to link PFC levels in the blood with changes in thyroid function using a nationally representative survey of American adults,” said one of the study’s authors, Chien-Yu Lin, MD, PhD, of En Chu Kong Hospital in Taiwan.

Women who had higher levels of a PFC called perfluorooctanoate (PFOA) in their blood tended to have elevated levels of the thyroid hormone triiodothyronine (T3). The study also found an increase in levels of T3 and the thyroid hormone thyroxine (T4) in women with higher concentrations of the PFC perfluorohexane sulfonate (PFHxS) in their blood. The levels rose without the pituitary gland signaling the thyroid to produce more hormones, which is the body’s natural mechanism for adjusting thyroid hormone levels. Men exposed to higher amounts of PFHxS, however, tended to have lower levels of the T4 hormone.

Even though people with a history of thyroid diseases were excluded from the study, researchers found an association between subclinical, or mild, hypothyroidism and elevated levels of PFOA, PFHxS and perfluorooctane sulfonate (PFOS) in women. Hypothyroidism occurs when the thyroid gland does not produce enough hormones and can cause symptoms such as fatigue, mental depression, weight gain, feeling cold, dry skin and hair, constipation and menstrual irregularities. This relationship needs to be explored and confirmed through additional research, Lin said.

The researchers analyzed data from 1,181 participants in the 2007-2008 and 2009-2010 National Health and Nutrition Examination Survey (NHANES), a population-based survey conducted by the Centers for Disease Control and Prevention (CDC). The study reviewed levels of four different PFCs as well as thyroid function.

“Although some PFCs such as PFOS have been phased out of production by major manufacturers, these endocrine-disrupting chemicals remain a concern because they linger in the body for extended periods,” Lin said. “Too little information is available about the possible long-term effects these chemicals could have on human health.”

###

Other researchers working on the study include: L. Wen of En Chu Kong Hospital, L. Lin and T. Su of National Taiwan University Hospital and P. Chen of National Taiwan University College of Public Health.

The article, “Association between Serum Perfluorinated Chemicals and Thyroid Function in U.S. Adults: the National Health and Nutrition Examination Survey 2007-2010,” was published online July 17.

Founded in 1916, The Endocrine Society is the world’s oldest, largest and most active organization devoted to research on hormones and the clinical practice of endocrinology. Today, The Endocrine Society’s membership consists of over 16,000 scientists, physicians, educators, nurses and students in more than 100 countries. Society members represent all basic, applied and clinical interests in endocrinology. The Endocrine Society is based in Chevy Chase, Maryland. To learn more about the Society and the field of endocrinology, visit our site at http://www.endocrine.org. Follow us on Twitter at https://twitter.com/#!/EndoMedia.

BPA and Chlorine Means Bad News: Modified Forms of Bisphenol A Found to Alter Hormone Signaling in New, Disturbing Ways

The ubiquity of the endocrine-disrupting chemical bisphenol A led researchers to ask what it might be doing in publicly supplied, chlorinated drinking water. The answer: Chlorinated BPA has different, but no less profound effects on cell-signaling networks than unmodified BPA. (Credit: © Artusius / Fotolia)

July 17, 2013 — The ubiquity of the endocrine-disrupting chemical bisphenol A led researchers to ask what it might be doing in publicly supplied, chlorinated drinking water. The answer: Chlorinated BPA has different, but no less profound effects on cell-signaling networks than unmodified BPA.

For years, scientists have been worried about bisphenol A. The chemical is known as an “endocrine disruptor,” a substance that interferes with the body’s hormone signaling system, and it’s found in everything from plastic drink bottles to the linings of food and drink cans to the thermal paper used for cash register receipts — not to mention the urine of 92.6 percent of Americans over the age of six. BPA has been associated with the development of chronic diseases such as diabetes, asthma and ovarian dysfunction. In 2012, the FDA banned BPA from use in the production of baby bottles and drinking cups.

BPA’s ubiquity in the environment led researchers to ask what it might be doing in publicly supplied drinking water, which is contaminated at its source by BPA-laden discarded plastic and later picks up more of the chemical when it passes through PVC plastic pipes. Most public water supplies are chlorinated to kill bacteria, and the BPA in the water also becomes chlorinated, acquiring one or more chlorine atoms from the water around it. The question was, how does this chlorinated BPA behave in the body?

The answer, generated from cell-culture experiments, was that it produced different but no less profound effects. “We found that when you modify the BPA it works just as dramatically but in different ways on the same systems,” said University of Texas Medical Branch at Galveston professor Cheryl Watson, senior author of a paper on the study now online in Endocrine Disruptors.

Watson and graduate student René Viñas examined both chlorinated BPA and BPA that had undergone sulfonation and glucuronodation — two processes the body uses to make a compound easier to excrete. In all three cases the modified forms of BPA worked through membrane estrogen receptors to deactivate key signaling enzymes known as ERK and JNK kinases.

“These kinases are major control centers, gathering all the cell signals, making decisions and then expediting them,” Watson said. “If you change the dynamic by inactivating kinases, you can mess up cell signaling.”

Very low levels of modified BPA were sufficient to produce the results — a phenomenon commonly seen with membrane receptors. The responses followed what is known as a non-monotonic pattern, varying irregularly when different concentrations of modified BPA were tested. The large number of experimental procedures this made necessary were facilitated by a BIOMEK-FX robot, which Viñas programmed to considerably increase the efficiency and precision of the process.

“The robot cuts down on the experimenter time required, because it does so much of the mechanical work, and it makes results more replicable, because the robot does things exactly the same every time,” Watson said. “It gives us hope that we can make an impact even with the sheer volume of chemicals that we have to study and the detail we have to study them in.”

http://www.sciencedaily.com/releases/2013/07/130717132420.htm

 

BPA linked to a common birth defect in boys

Contact: Jenni Glenn Gingery jgingery@endocrine.org 301-941-0240 The Endocrine Society

SAN FRANCISCO– A new study links fetal exposure to a common chemical pollutant, bisphenol A (BPA), to defects of a testicular hormone in newborn boys with undescended testicles. The results, which were presented Monday at The Endocrine Society’s 95th Annual Meeting in San Francisco, suggest yet another potential harmful effect of BPA, which is widely used in many plastics, liners of food cans and dental sealants.

“Alone, our study cannot be considered as definitive evidence for an environmental cause of undescended testis,” said lead author Patrick Fenichel, MD, PhD, professor and head of reproductive endocrinology at the University Hospital of Nice in France. “But it suggests, for the first time in humans, a link that could contribute to one co-factor of idiopathic [unexplained] undescended testis, the most frequent congenital malformation in male newborns.”

Cryptorchidism, the medical name for undescended testicles, occurs in 2 to 5 percent of full-term male newborns, according to Fenichel. Sometimes the testicles descend on their own within six months after birth. If the condition persists and goes untreated, however, it carries an increased risk in adulthood of decreased fertility and testicular cancer, he said.

Fenichel and his colleagues studied 180 boys born after 34 weeks’ gestation between 2003 and 2005. Fifty-two were born with one or two undescended testicles, 26 of whom still had the condition at 3 months of age. The other 128 newborns did not have this birth defect and were matched for pregnancy term, weight and time of birth (the control group). Using sensitive immunoassays of the infants’ umbilical cord blood, the researchers measured the newborns’ levels of BPA and insulin-like peptide 3, one of the two testicular hormones that regulate descent of the testicles.

Testosterone level, which also controls fetal testicular descent, did not differ between the groups and was normal in the whole population, according to Fenichel.

The infants with cryptorchidism had significantly lower levels of insulin-like peptide 3, compared with the controls, the authors reported. These infants did not have greatly increased levels of BPA or several other environmental endocrine disrupters that were measured. However, in all 180 infants, the BPA level inversely correlated with the level of insulin-like peptide 3, meaning that the higher the BPA level, the lower the level of this important testicular hormone.

Fenichel speculated that BPA, an estrogenic endocrine disruptor, might repress, as other research has shown for estrogens in rodents, expression of the gene for insulin-like peptide 3. This could be a co-factor in the development of cryptorchidism, he said.

Animal research also has linked fetal BPA exposure to an increased risk of reproductive disorders and other health problems.

###

 

Founded in 1916, The Endocrine Society is the world’s oldest, largest and most active organization devoted to research on hormones and the clinical practice of endocrinology.  Today, The Endocrine Society’s membership consists of over 16,000 scientists, physicians, educators, nurses and students in more than 100 countries. Society members represent all basic, applied and clinical interests in endocrinology. The Endocrine Society is based in Chevy Chase, Maryland. To learn more about the Society and the field of endocrinology, visit our site at http://www.endocrine.org. Follow us on Twitter.

Man-made chemicals cited in health scourges -UN report : “a global threat that needs to be resolved,”

Tue, 19 Feb 2013 13:59 GMT

Reuters

* Childhood cancers, male sperm count cited

* Action said needed to avert global threat

* Product labels may not identify components

By Robert Evans

GENEVA, Feb 19 (Reuters) – Man-made chemicals in everyday products are likely to be at least the partial cause of a global surge in birth deformities, hormonal cancers and psychiatric diseases, a U.N.-sponsored  research team reported on Tuesday.

These substances, dubbed EDCs, could also be linked to a decline in the human male sperm count and female fertility, to an increase in once-rare childhood cancers and to the disappearance of some animal species, they said.

“It is clear that some of these chemical pollutants can affect the endocrinal (hormonal) system and ….may also interfere with the development processes of humans and wildlife species,” the report declared.

The international group, academic experts working under the umbrella of the United Nations environmental and health agencies UNEP and WHO, issued their findings in a paper updating a 2002 study on the potential dangers of synthetic chemicals.

Declaring “a global threat that needs to be resolved,” the team said humans and animals across the planet were probably exposed to hundreds of these often little-studied or understood compounds at any one time.

“We live in a world in which man-made chemicals have become part of everyday life,” said their 28-page report, “State of the Science of Endocrine Disrupting Chemicals, 2012,” issued as a policy guide for governments.

EDCs include phthalates long used in making plastics soft and flexible. Products made from them include toys, children’s dummies, perfumes and pharmaceuticals, as well as cosmetics like deodorants that are absorbed into the body.

Another is Bisphenol A, or BPA, which is used to harden plastics and is found in food and beverage containers, including some babies’ bottles and the coating of food cans.

A few countries – including the United States, Canada and some European Union members – have already banned the use of some of them in certain products, especially those destined for the use of children.

But, the report said, “many hundreds of thousands” are in use around the world and only a small fraction had been assessed for their potential to spark disease by upsetting the endocrinal, or hormonal, systems of humans and animals.

Experts believe that in general, such chemicals can be absorbed into drinks and food from the containers they come in.

COMPONENTS NOT IDENTIFIED

The team, created by a 17-year-old chemical management body called the IOMC working with a range of U.N. agencies, said a key problem was that manufacturers of consumer products did not identify many of their chemical components.

Consequently, the researchers said, they had only been able to look at “the tip of the iceberg”. Disease risk from the use of EDCs – or what could be even more dangerous a combination of them – “may be significantly underestimated.”

Using studies of the effect of the chemicals on humans and animals, the team added, a link to EDCs could be suspected in breast and prostate cancer, diabetes, infertility, asthma, obesity, strokes, and Alzheimer and Parkinson’s diseases.

Babies exposed to EDCs in the womb or in puberty, these studies suggested, were especially vulnerable to developing these diseases in later life as well as behavioral and learning problems like dyslexia as children.

In many countries, these disorders affected 5-10 percent of babies born, while autism was now recorded at a rate of one percent. Childhood leukemia and brain cancer is also on the rise, according to the report.

“All of these complex non-communicable diseases have both a genetic and an environmental component,” it said.

“Since the increases in incidence and prevalence cannot be due solely to genetics, it is important to focus on understanding the contribution of the environment to these chronic disease trends in humans.”

The researchers said their report had been based largely on studies in the developed world. But the size of the problem in developing countries had yet to be adequately assessed due to a lack of data from Africa, Asia and Latin America.  (Reported by Robert Evans; Editing by Mark Heinrich)

 

http://www.trust.org/alertnet/news/man-made-chemicals-cited-in-health-scourges–un-report/

Mild painkillers in pregnancy are associated with an increased risk of male reproductive problems

 2010 study posted for filing

Contact: Emma Mason wordmason@mac.com European Society of Human Reproduction and Embryology

New evidence has emerged that the use of mild painkillers such as paracetamol, aspirin and ibuprofen, may be part of the reason for the increase in male reproductive disorders in recent decades. Research published in Europe’s leading reproductive medicine journal Human Reproduction today (Monday 8 November) shows that women who took a combination of more than one mild analgesic during pregnancy, or who took the painkillers during the second trimester of pregnancy, had an increased risk of giving birth to sons with undescended testicles (cryptorchidism) – a condition that is known to be a risk factor for poor semen quality and testicular germ cell cancer in later life. [1]

The researchers from Denmark, Finland and France found that women who used more than one painkiller simultaneously (e.g. paracetamol and ibuprofen) had a seven-fold increased risk of giving birth to sons with some form of cryptorchidism compared to women who took nothing.

The second trimester appeared to a particularly sensitive time. Any analgesic use at this point in the pregnancy more than doubled the risk of cryptorchidism. Of the individual painkillers, ibuprofen and aspirin approximately quadrupled the risk of cryptorchidism, while a doubling of the risk (although non-statistically significant) was found for paracetamol. Simultaneous use of more than one painkiller during this time increased the risk 16-fold.

These findings were supported by work that the researchers Dr Ulla Hass at the Technical University of Denmark (Søborg, Denmark) and Dr Bernard Jégou from INSERM (Institut National de la Santé at de la Recherche Médicale) at the University of Rennes (Rennes, France) carried out in rats. They found that analgesics disrupted androgen production, leading to insufficient supplies of the male hormone testosterone during the crucial early period of gestation when the male organs were forming. The effects of the analgesics on the rats was comparable to that caused by similar doses of known endocrine (hormone) disrupters such as phthalates – a family of chemical compounds used in the manufacture of plastics such as PVC.

Dr Henrik Leffers, senior scientist at the Rigshospitalet in Copenhagen (Denmark), who led the research, said: “If exposure to endocrine disruptors is the mechanism behind the increasing reproductive problems among young men in the Western World, this research suggests that particular attention should be paid to the use of mild analgesics during pregnancy, as this could be a major reason for the problems.”

The study looked at two groups of women, 834 in Denmark and 1463 in Finland, who joined the study while they were pregnant. In Finland the women answered written questionnaires about their use of medication during pregnancy and in Denmark the women did the same or took part in a telephone interview, or both. The telephone interview asked specifically about the use of painkillers during pregnancy, while the written questionnaires did not. The baby boys were examined at birth for any signs of cryptorchidism, ranging from a mild form of the condition, in which the testis is located high in the scrotum, to the more severe form, in which the testis is so high up in the abdomen that it is non-palpable.

The researchers found that women significantly under-reported the use of painkillers in the written questionnaire because they did not consider mild painkillers to be “medication”. Among the 298 Danish mothers who took part in both the self-administered questionnaire and the telephone interview, 30.9% reported using painkillers in the questionnaire, but 57.2% reported it in the telephone interview.

The researchers could find no statistically significant effect in the group of Finnish women, but found significant effects amongst the Danish women.

Dr Leffers said: “We do not quite understand why the Finnish cohort does not show the same associations as the Danish cohort. However, the use of mild analgesics in the Finnish cohort was only examined by questionnaires, not by telephone interviews, and the telephone interviews gave the most reliable information in the Danish cohort, which may explain some of the differences. Moreover, the prevalence of cryptorchidism is much lower in Finland (2.4%) compared to Denmark (9.3%) and, therefore, this would require a larger cohort to find the same number of cases.”

The work examining the effects of the analgesics in rats showed that intrauterine exposure to paracetamol reduced the anogenital distance (the distance between the anus and the genitals) in the offspring. AGD is a sensitive marker for reduced intrauterine androgen levels and effects on AGD predicts increased risk for impaired reproductive performance of the adult animal. The researchers also found that mild analgesics reduced levels of testosterone in the rat foetal testis by approximately 50%.

Dr Jégou said that the mechanism by which mild analgesics reduced testosterone was poorly understood. “It seems to be related to their mode of action which involves inhibiting the production of prostaglandins – locally acting messenger molecules. In another study by David Kristensen et al., we have shown that endocrine disruptors of the phthalate type are almost as potent inhibitors of prostaglandin synthesis as pharmaceutical inhibitors such as mild analgesics. However, currently we do not know how a reduction of prostaglandin synthesis can reduce testosterone production.”

The researchers say that there has been a marked increase in the incidence of congenital cryptorchidism in recent decades, notably in Denmark where it has increased from 1.8% in 1959-1961 to 8.5% in 1997-2001. “The magnitude of this difference is too large to be accounted for by random fluctuations and differences in ascertainment. Moreover, this finding is in accordance with the reported decline in reproductive health in the adult male population over the past five decades,” they write in their paper.

Dr Leffers said: “Although we should be cautious about any over-extrapolation or over-statement, the use of mild analgesics constitutes by far the largest exposure to endocrine disruptors among pregnant women, and use of these compounds is, at present, the best suggestion for an exposure that can affect a large proportion of the human population.”

The researchers say that the risk from the analgesics is markedly higher than that seen for known endocrine disrupters such as phthalates, and that, as most Western women are inevitably exposed to low levels of endocrine disrupters, these together with analgesic use, could be contributing to the increased incidence of cryptorchidism and later life reproductive problems.

Dr Leffers said: “A single paracetamol tablet (500 mg) contains more endocrine disruptor potency than the combined exposure to the ten most prevalent of the currently known environmental endocrine disruptors during the whole pregnancy. In fact, a single tablet will, for most women, be at least a doubling of the exposure to the known endocrine disruptors during the pregnancy and that dose comes on a single day, not spread out over nine months as with the environmental endocrine disruptors. Thus, for women using mild analgesics during the pregnancy, the mild analgesics will be by far the largest exposure to endocrine disruptors.”

The researchers say that more research is urgently needed, particularly epidemiological studies. They also recommend that advice to pregnant women on analgesic use should be reconsidered. “Women may want to try to reduce their analgesic use during pregnancy,” said Dr Leffers. “However, as biologists this is not something we can advise women about. So we recommend that pregnant women seek advise from their physician before using mild analgesics and in general follow the advice to use as little medicine during pregnancy as possible.”

###

[1] “Intrauterine exposure to mild analgesics is a risk factor for development of male reproductive disorders in human and rat”, by David M. Kristensen et al. Human Reproduction journal. doi:10.1093/humrep/deq323

Exposure to low doses of BPA ( within 12 Hours ) alters gene expression in the fetal mouse ovary

Contact: Patricia A. Hunt pathunt@wsu.edu 509-335-4954 Society for the Study of Reproduction

Significant changes in gene expression in the fetal ovary are evident in female mice whose mothers are exposed to low doses of bisphenol A

A study posted today (Wednesday, August 25) at the online site of the journal Biology of Reproduction reports that exposure of pregnant female mice to the endocrine-disrupting chemical bisphenol A may produce adverse reproductive consequences on gene expression in fetal ovaries as early as 12 hours after the mother has first been exposed to the chemical.

Bisphenol A (BPA) is a chemical used in plastics for making some baby and water bottles, linings of food and beverage cans, and other human consumer products.

The mice in this study were given BPA at doses thought to be equivalent to levels currently being experienced by humans.

The research, conducted in the laboratory of Dr. Patricia A. Hunt at Washington State University (WSU) in Pullman, showed that BPA exposure affects the earliest stages of egg production in the ovaries of the developing mouse fetuses, thus suggesting that the next generation (the grandchildren of the females given BPA) may suffer genetic defects in such biological processes as mitosis and DNA replication.

In addition, the WSU research team noted that their study “revealed a striking down-regulation of mitotic/cell cycle genes, raising the possibility that BPA exposure immediately before meiotic entry might act to shorten the reproductive lifespan of the female” by reducing the total pool of fetal oocytes.

Future studies in Dr. Hunt’s laboratory will focus on genetic changes produced over a range of BPA exposure

Prenatal exposure to endocrine-disrupting chemicals linked to breast cancer

2010 study for filing
Contact: Aaron Lohr
alohr@endo-society.org
240-482-1380
The Endocrine Society

A study in mice reveals that prenatal exposure to endocrine-disrupting chemicals, like bisphenol-A (BPA) and diethylstilbestrol (DES), may program a fetus for life. Therefore, adult women who were exposed prenatally to BPA or DES could be at increased risk of breast cancer, according to a new study accepted for publication in Hormones & Cancer, a journal of The Endocrine Society.

Endocrine-disrupting chemicals are substances in the environment that interfere with hormone biosynthesis, metabolism or action resulting in adverse developmental, reproductive, neurological and immune effects in both humans and wildlife. These chemicals are designed, produced and marketed largely for specific industrial purposes.

“BPA is a weak estrogen and DES is a strong estrogen, yet our study shows both have a profound effect on gene expression in the mammary gland (breast) throughout life,” said Hugh Taylor, MD, of the Yale University School of Medicine in New Haven, Conn. and lead author of the study. “All estrogens, even ‘weak’ ones can alter the development of the breast and ultimately place adult women who were exposed to them prenatally at risk of breast cancer.”

In this study, researchers treated pregnant mice with BPA or DES and then looked at the offspring as adults. When the offspring reached adulthood, their mammary glands still produced higher levels of EZH2, a protein that plays a role in the regulation of all genes. Higher EZH2 levels are associated with an increased risk of breast cancer in humans.

“We have demonstrated a novel mechanism by which endocrine-disrupting chemicals regulate developmental programming in the breast,” said Taylor. “This study generates important safety concerns about exposures to environmental endocrine disruptors such as BPA and suggests a potential need to monitor women exposed to these chemicals for the development of breast lesions as adults.”

 

 

###

 

 

Other researchers working on the study include Leo Doherty, Jason Bromer, Yuping Zhou and Tamir Aldad of the Yale University School of Medicine in New Haven, Connecticut.

The article, “In Utero Exposure to Diethylstilbestrol (DES) or Bisphenol-A (BPA) Increases EZH2 Expression in the Mammary Gland: An Epigenetic Mechanism Linking Endocrine Disruptors to Breast Cancer,” has been published online and can be found at: http://www.springerlink.com/content/547256j0g02073v5/?p=286f52b5d3c94d9f8dc4546af408af89π=0.

Founded in 1916, The Endocrine Society is the world’s oldest, largest and most active organization devoted to research on hormones and the clinical practice of endocrinology. Today, The Endocrine Society’s membership consists of over 14,000 scientists, physicians, educators, nurses and students in more than 100 countries. Society members represent all basic, applied, and clinical interests in endocrinology. The Endocrine Society is based in Chevy Chase, Maryland. To learn more about the Society and the field of endocrinology, visit our site at www.endo-society.org.

141st Health Research Report 02 NOV 2012

 

Editors Top Five:

 

1. Study: Flame Retardant ‘Firemaster 550’ Is an Endocrine Disruptor (Major Weight Gain)

2. Feinstein Institute researchers discover that bean used in Chinese food could protect against sepsis

3. Drop in testosterone tied to prostate cancer recurrence

4. Study suggests too much risk associated with SSRI usage and pregnancy

5. Researchers discover watching horror films can help you burn equivalent of a chocolate bar, with The Shining burning most

 

 

 

 

In this issue:

 

1. Task Force Recommends Against Hormone Replacement Therapy for Postmenopausal Women

2. Antibiotics not effective for cough due to ‘common cold’ in children

3. Exercise may trump mental activity in protecting against brain shrinkage

4. Selenium deficiency may cause cardiomyopathy post-gastric bypass

5. Crusty foods may worsen heart problems associated with diabetes

6. New vitamin-based treatment that could reduce muscle degeneration in muscular dystrophy

7. Study: Flame Retardant ‘Firemaster 550’ Is an Endocrine Disruptor (Major Weight Gain)

8. Scripps Research Institute Study Suggests Caution and Further Studies on Drugs Used to Treat Macular Degeneration

9. Researchers develop cocktail of bacteria that eradicates Clostridium difficile infection

10. Feinstein Institute researchers discover that bean used in Chinese food could protect against sepsis

11. Drop in testosterone tied to prostate cancer recurrence

12. Exercise is smart for your heart – and makes you smarter

13. New study reveals that every single junk food meal damages your arteries

14. Common food preservative may slow, even stop tumor growth

15. Study suggests too much risk associated with SSRI usage and pregnancy

16. Men who do exercise produce better quality semen

17. Green tea found to reduce rate of some GI cancers

18. Researchers discover watching horror films can help you burn equivalent of a chocolate bar, with The Shining burning most

Health Research Report

141st Issue Date 02 NOV 2012

Compiled By Ralph Turchiano

www.healthresearchreport.me www.vit.bz

www.youtube.com/vhfilm www.facebook.com/engineeringevil

www.engineeringevil.com

 

Study: Flame Retardant ‘Firemaster 550’ Is an Endocrine Disruptor: causes extreme weight gain

For Immediate Release

Matt Shipman | News Services | 919.515.6386

Dr. Heather Patisaul | 919.513.7567

Release Date: 10.24.2012 Filed under Releases

The flame-retardant mixture known as “Firemaster 550” is an endocrine disruptor that causes extreme weight gain, early onset of puberty and cardiovascular health effects in lab animals, according to a new study spearheaded by researchers from North Carolina State University and Duke University.

Firemaster 550 is made up of four principal component chemicals and is used in polyurethane foam in a wide variety of products, ranging from mattresses to infant nursing pillows. The flame-retardant mixture was developed by Chemtura Corp., and was first identified by the research community in 2008. It was developed to replace a class of fire retardants being phased out of use because of concerns regarding their safety.  This new study represents the first public data on whether Firemaster 550 has potential health effects.

In this pilot study, pregnant lab rats were assigned to three groups: a control group, which was not exposed to Firemaster 550; a “low-dose” group, which ingested 100 micrograms of Firemaster 550 once per day throughout pregnancy and nursing; and a “high-dose” group, which ingested 1,000 micrograms on the same schedule. These environmentally relevant doses are lower than the doses used in industry-funded studies. Researchers then evaluated the physiological outcomes of the exposure in both the mothers (called dams) and the offspring (called pups).

Importantly, the researchers detected TBB, one of Firemaster 550’s component chemicals, in the fat of all the exposed dams and offspring, but none of the unexposed animals. This means the flame retardant is capable of crossing the placenta during pregnancy, reaching infants via breast milk, or both.

Because flame retardants that have been phased out are known to disrupt thyroid function, and Firemaster 550 includes chemicals with structural similarities, the researchers looked at circulating thyroid hormone levels in dams at the end of the nursing period. The high-dose dams had much higher thyroid hormone levels than the control group, while low-dose dams had marginally higher thyroid hormone levels. This is significant because thyroid hormones influence brain development during pregnancy, as well as a host of other biological functions, such as metabolism.

Researchers also found extremely rapid weight gain in the offspring. By the time they were weaned from nursing, high-dose male pups were 60 percent heavier than the control group – and high-dose female pups were 31 percent heavier than the control group.

The increased weight in female pups contributed to the early onset of puberty. The control group hit puberty at 33 days old, while the high-dose group hit puberty at 29 days.

High-dose female pups also had difficulty regulating their glucose levels as adults. High-dose males had thickened walls in the left ventricle of the heart, suggestive of cardiovascular disease.

“This study indicates that Firemaster 550 is an endocrine disruptor, and that raises a lot of important questions,” says Dr. Heather Patisaul, an assistant professor of biology at NC State and lead author of a paper describing the work. “This was a small-scale study. We need to continue this work with a larger sample size and look at a broader range of potential effects related to obesity, thyroid hormone function and metabolic syndrome. We also want to determine which of the component chemicals in Firemaster 550 are responsible for the various effects.”

The paper, “Accumulation and Endocrine Disrupting Effects of the Flame Retardant Mixture Firemaster 550 in Rats: An Exploratory Assessment,” is published online in the Journal of Biochemical and Molecular Toxicology. Co-authors include NC State undergraduate Natalie Mabrey; NC State research technician Katherine McCaffrey; Heather Stapleton and Simon Roberts of Duke University; Robin Gear and Scott Belcher of the University of Cincinnati; and Joe Braun of Brown University. The research was funded by the National Institute of Environmental Health Sciences.

-shipman-

Note to Editors: The study abstract follows.

“Accumulation and Endocrine Disrupting Effects of the Flame Retardant Mixture Firemaster 550 in Rats: An Exploratory Assessment”

Authors: Heather B. Patisaul, Natalie Mabrey and Katherine A. McCaffrey, North Carolina State University; Simon C. Roberts and Heather M. Stapleton, Duke University; Robin B. Gear and Scott M. Belcher, University of Cincinnati; and Joe Braun, Brown University

Published: Online Oct. 24 in Journal of Biochemical and Molecular Toxicology

Abstract: Firemaster 550 (FM 550), a fire-retardant mixture used in foam-based products, was recently identified as a common contaminant in household dust. The chemical structures of its principle components suggest they have endocrine disrupting activity, but nothing is known about their physiological effects at environmentally relevant exposure levels. The goal of this exploratory study was to evaluate accumulation, metabolism and endocrine disrupting effects of FM 550 in rats exposed to 100 or 1000 [micrograms]/day across gestation and lactation. FM 550 components accumulated in tissues of exposed dams and offspring and induced phenotypic hallmarks associated with metabolic syndrome in the offspring. Effects included increased serum thyroxine levels and reduced hepatic carboxylesterease activity in dams, and advanced female puberty, weight gain, male cardiac hypertrophy, and altered exploratory behaviors in offspring. Results of this study are the first to implicate FM 550 as an endocrine disruptor and an obesogen at environmentally relevant levels.

Health effects of pesticide mixtures are Deadly: Unexpected insights from the salmon brain

Contact: Ben Sherman ben.sherman@noaa.gov202-253-5256 NOAA Headquarters

In his research, scientist Nat Scholz examines how pesticides that run off the land and mix in rivers and streams combine to have a greater than expected toxic effect on the salmon nervous system. These pesticides are widely used in the United States and their occurrence as mixtures in the food supply for humans may also pose an unexpected risk for people.

“We have a pretty good handle on how to assess the health effects of single chemicals in conventional toxicity trials,” said Scholz, a fishery biologist with the National Oceanic and Atmospheric Administration. “But the real world is usually more complex, and exposures to mixtures of chemicals can be more of the rule than the exception. One of the major scientific challenges of our generation is to develop new approaches to anticipate and head off any ill effects of interacting chemicals.”

Scholz will present his research along with five other scientists from the U.S. government, the Canadian government and academia in the symposium entitled “From Kitchen Sinks to Ocean Basins: Emerging Chemical Contaminants and Human Health.” Organized by NOAA’s Oceans and Human Health Initiative, the symposium is one of the features of the AAAS Annual Meeting.

Scholz and his colleagues found that salmon died when exposed to combinations of pesticides that were not deadly when tested in individual trials. The findings for salmon could have important implications for the recovery of many threatened and endangered salmon populations throughout the western United States. The research also points to the need for more study of how combinations of pesticides found on fruits and vegetables may be affecting humans.

###

To learn more about Dr. Scholz’s research, please attend his presentation. Journalists are welcome to interview Dr. Scholz. To set up an interview, please call Monica Allen at 202-379-6693 or Ben Sherman at 202-253-5256. For more information on the Oceans and Human Health Initiative go to www.nwfsc.noaa.gov/ohh

Reposted from 2008

Antibacterial chemical in Soap disrupts hormone activities – Triclocarban, Triclosan causes Prostate Growth

A new UC Davis study shows that a common antibacterial chemical added to bath soaps can alter hormonal activity in rats and in human cells in the laboratory—and does so by a previously unreported mechanism.

The findings come as an increasing number of studies – of both lab animals and humans – are revealing that some synthetic chemicals in household products can cause health problems by interfering with normal hormone action.

Called endocrine disruptors, or endocrine disrupting substances (EDS), such chemicals have been linked in animal studies to a variety of problems, including cancer, reproductive failure and developmental anomalies

This is the first endocrine study to investigate the hormone effects of the antibacterial compound triclocarban (also known as TCC or 3,4,4′-trichlorocarbanilide), which is widely used in household and personal care products including bar soaps, body washes, cleansing lotions, wipes and detergents. Triclocarban-containing products have been marketed broadly in the United States and Europe for more than 45 years; an estimated 1 million pounds of triclocarban are imported annually for the U.S. market.

The researchers found two key effects: In human cells in the laboratory, triclocarban increased gene expression that is normally regulated by testosterone. And when male rats were fed triclocarban, testosterone-dependent organs such as the prostate gland grew abnormally large.

Also, the authors said their discovery that triclocarban increased hormone effects was new. All previous studies of endocrine disruptors had found that they generally act by blocking or decreasing hormone effects.

“This finding may eventually lead to an explanation for some rises in some previously described reproductive problems that have been difficult to understand,” said one author, Bill Lasley, a UC Davis expert on reproductive toxicology and professor emeritus of veterinary medicine. More analyses of antibacterials and endocrine effects are planned, he said.

Household chemical may affect breast development – Phthalate

A chemical found in household fittings has been found to affect the development of the mammary gland in rats and further studies will be required to determine if the presence of this chemical could lead to breast cancer. New research published in the online open access journal BMC Genomics is the first to show that this chemical can affect the breasts’ genomic profile.

Jose Russo and coworkers from the Fox Chase Cancer Center in Philadelphia, along with colleagues from the University of Alabama in Birmingham, US, fed lactating rats with butyl benzyl phthalate (BBP), which their offspring then absorbed via breast milk. The offspring ingested levels of chemical estimated to be nearly equivalent to the Environmental Protection Agency’s safe dose limit of BBP for humans.

The researchers found that BBP had a transitory effect on certain characteristics of the female offspring of the rats, such as the ratio of uterine weight to body weight and the genetic profile of the mammary gland. Dr Russo stated: “We are the first to report that neonatal/prepubertal exposure to BBP induced modifications in the gene expression of the mammary tissue.”

Although these effects wore off once exposure to BBP was removed, the subtle changes in the mammary gland may have an effect later in life

BBP is widely used as a plasticizer, an additive used to soften polymers, and is found in household fittings such as pipes, vinyl floor tiles and carpet backing. This type of chemical is known to be an endocrine disruptor, which mimics the effect of hormones. Endocrine disruptors are known to damage wildlife and they have also been implicated in reduced sperm counts and neurological problems in humans.

Consuming canned soup linked to greatly elevated levels of the chemical BPA, 1,221% increase in BPA

BPA, found in soup can lining, associated with adverse health effects in humans

A new study from researchers at the Harvard School of Public Health (HSPH) has found that a group of volunteers who consumed a serving of canned soup each day for five days had a more than 1,000% increase in urinary bisphenol A (BPA) concentrations compared with when the same individuals consumed fresh soup daily for five days. The study is one of the first to quantify BPA levels in humans after ingestion of canned foods.

The findings were published online November 22, 2011, in the Journal of the Medical Association (JAMA) and will appear in the November 23/30 print issue.

“Previous studies have linked elevated BPA levels with adverse health effects. The next step was to figure out how people are getting exposed to BPA. We’ve known for a while that drinking beverages that have been stored in certain hard plastics can increase the amount of BPA in your body. This study suggests that canned foods may be an even greater concern, especially given their wide use,” said Jenny Carwile, a doctoral student in the Department of Epidemiology at HSPH and lead author of the study.

Exposure to the endocrine-disrupting chemical BPA, used in the lining of metal food and beverage cans, has been shown to interfere with reproductive development in animals and has been linked with cardiovascular disease, diabetes, and obesity in humans. In addition to the lining of food and beverage cans, BPA is also found in polycarbonate bottles (identified by the recycling number 7) and dentistry composites and sealants.

The researchers, led by Carwile and Karin Michels, associate professor in the Department of Epidemiology, set out to quantify whether canned-soup consumption would increase urinary BPA concentrations relative to eating fresh soup.

They recruited student and staff volunteers from HSPH. One group consumed a 12-ounce serving of vegetarian canned soup each day for five days; another group consumed 12 ounces of vegetarian fresh soup (prepared without canned ingredients) daily for five days. After a two-day “washout” period, the groups reversed their assignments.

Urine samples of the 75 volunteers taken during the testing showed that consumption of a serving of canned soup daily was associated with a 1,221% increase in BPA compared to levels in urine collected after consumption of fresh soup.

The researchers note that the elevation in urinary BPA concentrations may be temporary and that further research is needed to quantify its duration.

“The magnitude of the rise in urinary BPA we observed after just one serving of soup was unexpected and may be of concern among individuals who regularly consume foods from cans or drink several canned beverages daily. It may be advisable for manufacturers to consider eliminating BPA from can linings,” said Michels, senior author of the study.