Fracking Chemicals Exposure May Harm Fertility Even at Very Low Dose

Adverse Reproductive and Developmental Health Outcomes Following Prenatal Exposure to a Hydraulic Fracturing Chemical Mixture in Female C57Bl/6 Mice

Unconventional oil and gas operations using hydraulic fracturing can contaminate surface and groundwater with endocrine-disrupting chemicals.

We have previously shown that 23 of 24 commonly used hydraulic fracturing chemicals can activate or inhibit the estrogen, androgen, glucocorticoid, progesterone, and/or thyroid receptors in a human endometrial cancer cell reporter gene assay and that mixtures can behave synergistically, additively, or antagonistically on these receptors.

Adverse Reproductive and Developmental Health Outcomes Following Prenatal Exposure to a Hydraulic Fracturing Chemical Mixture in Female C57Bl/6 Mice, Endocrine Society Endocrinology, July 05, 2016.

In the current study, pregnant female C57Bl/6 dams were exposed to a mixture of 23 commonly used unconventional oil and gas chemicals at approximately 3, 30, 300, and 3000 μg/kg·d, flutamide at 50 mg/kg·d, or a 0.2% ethanol control vehicle via their drinking water from gestational day 11 through birth.

This prenatal exposure to oil and gas operation chemicals suppressed pituitary hormone concentrations across experimental groups (prolactin, LH, FSH, and others), increased body weights, altered uterine and ovary weights, increased heart weights and collagen deposition, disrupted folliculogenesis, and other adverse health effects.

This work suggests potential adverse developmental and reproductive health outcomes in humans and animals exposed to these oil and gas operation chemicals, with adverse outcomes observed even in the lowest dose group tested, equivalent to concentrations reported in drinking water sources. These endpoints suggest potential impacts on fertility, as previously observed in the male siblings, which require careful assessment in future studies.

Fracking chemicals exposure linked to altered hormone levels, ovarian development

EDCs exposure and adverse reproductive and developmental outcomes in female mice

Washington, DC – Prenatal exposure to chemicals used in hydraulic fracturing, or fracking, may threaten fertility in female mice, according to a new study published in the Endocrine Society’s journal Endocrinology.

The study was the first to find a link between chemical exposure and adverse reproductive and developmental outcomes in female mice. Scientists exposed the mice to 23 chemicals commonly used in fracking, as well as oil and gas development, to study their effects on key hormones.

Fracking Chemicals Exposure May Harm Fertility in Female Mice, Endocrine Society, August 25, 2016.

Adverse Reproductive and Developmental Health Outcomes Following Prenatal Exposure to a Hydraulic Fracturing Chemical Mixture in Female C57Bl/6 Mice, Endocrine Society Endocrinology, July 05, 2016.

Researchers have previously found that these chemicals are endocrine-disrupting chemicals (EDCs) that mimic or block the body’s hormones—the chemical messengers that regulate respiration, reproduction, metabolism, growth and other biological functions. More than 1,300 studies have found links between EDCs and serious health conditions such as infertility, diabetes, obesity, hormone-related cancers and neurological disorders, according to the Endocrine Society’s 2015 Scientific Statement.

The study’s senior author, Susan C. Nagel, PhD, of the University of Missouri in Columbia, MO., said:

“The evidence indicates that developmental exposure to fracking and drilling chemicals may pose a threat to fertility in animals and potentially people.

Negative outcomes were observed even in mice exposed to the lowest dose of chemicals, which was lower than the concentrations found in groundwater at some locations with past oil and gas wastewater spills.”

The researchers mixed 23 oil and gas chemicals in four different concentrations to reflect concentrations ranging from those found in drinking water and groundwater to concentrations found in industry wastewater. The mixtures were added to drinking water given to pregnant mice in the laboratory from day 11 of pregnancy until they gave birth. The female offspring of the mice that drank the chemical mixtures were compared to female offspring of mice in a control group that was not exposed.

The mice exposed to the drilling chemicals had lower levels of key hormones related to reproductive health—prolactin, follicle stimulating hormone (FSH) and luteinizing hormone— compared to the control group. Mice exposed to smaller doses of the chemicals had fewer ovarian follicles, or pockets where egg cells are stored, which suggests they have a reduced number of eggs and may have a shorter fertile period than other mice. In contrast, the mice exposed to the highest chemical dose had an increase in the primary follicle number, which could signal inappropriate follicle activation and ultimate follicle death.

The mice exposed to the chemicals in utero also tended to weigh about 10 percent more at 21 days of age than mice that were not exposed to chemicals. The mice that were exposed to chemicals had increased heart weights and other indicators for abnormal thickening of the heart muscle, which were not seen in the control group.

“Female mice that were exposed to commonly used fracking chemicals in utero showed signs of reduced fertility, including alterations in the development of the ovarian follicles and pituitary and reproductive hormone concentrations.

These findings build on our previous research, which found exposure to the same chemicals was tied to reduced sperm counts in male mice. Our studies suggest adverse developmental and reproductive health outcomes might be expected in humans and animals exposed to chemicals in regions with oil and gas drilling activity.”

Nagel said.
Fracking image via danielfoster.

Endocrine Society Experts Concerned EU Chemical Criteria Will Not Protect Public

European Commission’s proposal ignores state of science on endocrine disruptors

Washington, DC – The European Commission’s narrow criteria for endocrine-disrupting chemicals will make it nearly impossible for scientists to meet the unrealistically high burden of proof and protect the public from dangerous chemicals, the Endocrine Society said in a response sent to the Commission.

More than 1,300 studies have found connections between endocrine-disrupting chemical (EDC) exposure and serious health conditions such as infertility, diabetes, obesity, hormone-related cancers and neurological disorders, according to the Endocrine Society’s 2015 Scientific Statement.

The European Union is the largest single economy with a regulation specific to EDCs. In order for it to be enforced, this regulation requires the European Commission to propose criteria to identify EDCs, similar to those used for the identification of carcinogens or other health hazards.

Endocrine Society Experts Concerned EU Chemical Criteria Will Not Protect Public, Endocrine Society, July 27, 2016.

Despite the body of evidence, the European Commission’s proposed criteria call for waiting until a chemical is known to cause adverse effects relevant to human health before taking action. Since it can take years or even generations for the health effects of EDCs to become apparent, this approach would allow chemicals to cause significant harm to populations before the chemicals could be regulated. When research shows that a given chemical is harmful to animals or human cells, that scientific evidence needs to be taken into account.

“The European Commission’s restrictive definition defeats the purpose of the regulations—to shield the public from endocrine-disrupting chemicals that pose a threat to human health,”

said Rémy Slama, PhD, a member of the Society’s European Union Endocrine-Disrupting Chemicals Task Force.

“By adopting these criteria, the Commission has set the European Union on a course to abandon the precautionary principle. Regulation of chemicals should err on the side of protecting the public and the environment from harm. Asking for an even stronger level of scientific evidence for endocrine disruptors than for carcinogens, for which the level of proof required is already very high, would be going in the wrong direction.”

The Society submitted a public comment responding to the European Commission’s criteria. As the oldest and largest global membership organization representing scientists and physicians who are experts on the body’s system of glands and hormones, the Society has been advocating on the European Union’s definition of EDCs since 2013.

EDCs can mimic, block or interfere with hormones that regulate key biological functions, including brain development, reproduction, metabolism and growth. Bisphenol A and other EDCs can be found in common products, including food containers, plastics, cosmetics and pesticides.

Failure to effectively regulate EDCs comes with a high price tag. Recent studies have found that adverse health effects from EDC exposure cost the European Union more than €163 billion each year in healthcare expenses and lost productivity.

The Society has supported a tiered regulatory approach that would rank EDCs based on available scientific evidence. As the European Parliament and member countries consider whether to implement the European Commission’s criteria, the Society will continue to advocate for criteria that reflect the state of the science

Endocrine Society Experts Urged EU to Protect Public from Chemical Exposure

Science-based regulation needed to address danger of endocrine-disrupting chemicals

Washington, DC – To protect human health, Endocrine Society members called on the European Commission to adopt science-based policies for regulating endocrine-disrupting chemicals in an opinion piece published in The Lancet Diabetes & Endocrinology.

Endocrine-disrupting chemicals (EDCs) mimic, block or interfere with the body’s hormones – the chemical signals that regulate brain development, reproduction, metabolism, growth and other important biological functions. EDCs can be found in common products including food containers, plastics, cosmetics and pesticides.

Endocrine Society Experts Urge EU to Protect Public from Chemical Exposure, The Endocrine Society, June 13, 2016.

Pool image Richard P J Lambert.

More than 1,300 studies have linked EDC exposure to health problems such as infertility, diabetes, obesity, hormone-related cancers and neurological disorders, according to the Endocrine Society’s 2015 Scientific Statement. Recent studies have found that adverse health effects from EDC exposure cost the European Union more than €157 billion each year in healthcare expenses and lost productivity.

“A growing body of research has found endocrine-disrupting chemicals pose a threat not only to those who are directly exposed, but to their children, grandchildren and great-grandchildren,”
“We need to protect the public and future generations with regulations that address the latest scientific findings and incorporate new information from emerging research.”

said the Society’s European Union Endocrine-Disrupting Chemicals Task Force Co-Chair Jean-Pierre Bourguignon, MD, PhD, first author of the opinion piece, of the University of Liège in Liège, Belgium.

The European Commission has proposed four options for regulatory criteria identifying endocrine-disrupting chemicals. The Endocrine Society supports option 3, which would create multiple categories based on the amount of scientific evidence that a particular chemical acts as an endocrine disruptor. This option also allows for incorporating new data as more studies are published.

In The Lancet Diabetes & Endocrinology, the authors note that other options being considered either don’t define endocrine-disrupting chemicals as clearly or include problematic criteria. Option 4 uses potency – the amount of chemical exposure needed to produce an effect – as one criterion. Since EDCs can have different and more dangerous effects when an individual is exposed to low levels, measuring potency could cause regulators to overlook endocrine disruptors that pose a true threat.

“Because of the way hormones work, even low-level exposure can disrupt the way the body grows and develops,”
“Pregnant women, babies and children are particularly vulnerable, and science-based regulations are needed to protect them.”

Bourguignon said.

Science-based regulation of endocrine disrupting chemicals in Europe: which approach?, the lancet,
, 13 June 2016.

Other authors of the opinion piece include: Rémy Slama of Inserm, CNRS and University Grenoble Alpes in Grenoble, France; Åke Bergman of the Swedish Toxicology Sciences Research Center in Södertälje, Sweden; Barbara Demeneix of Muséum National d’Histoire Naturelle in Paris, France; Richard Ivell of the University of Nottingham in Nottingham, U.K.; Andreas Kortenkamp of Brunel University London in Uxbridge, U.K.; GianCarlo Panzica of the University of Torino and Neuroscience Institute Cavalieri Ottolenghi in Orbassano, Italy; Leonardo Trasande of New York University School of Medicine in New York, NY; and R. Thomas Zoeller of the University of Massachusetts in Amherst, MA.

BPA may predispose babies in womb to breast cancer later in life

BPA Changes Fetal Development of the Mammary Gland in Ways That Can Raise Breast Cancer Risk

Boston, MA – A new culture system that tests the role of chemical exposure on the developing mammary gland has found that Bisphenol A (BPA) directly affects the mammary gland of mouse embryos. The study results, to be presented Friday at the Endocrine Society’s 98th annual meeting in Boston, show that these changes to embryonic mammary tissue occur at a dose comparable to that of humans’ environmental exposure to BPA.

“We exposure in the womb to endocrine disruptors such as BPA may be a main factor responsible for the increased incidence of breast cancer in women,”

said the study’s lead investigator, Lucia Speroni, PhD, a research associate and member of the Soto-Sonnenschein lab at Tufts University School of Medicine in Boston.

“We knew from our previous research that BPA causes changes to breast tissue associated with a higher predisposition to breast cancer later in life. However, until now, we did not know whether this was a direct effect on the fetus or an indirect effect from the mother’s exposure.”

said Speroni, who helped develop the new biological assay.

BPA is a hormone-like industrial chemical that appears in many plastic and resin household products and food containers. It has been detected in most urine samples representative of the U.S. population. Research links BPA to numerous adverse health effects in humans, and it can cross the placenta in the womb.

BPA Changes Fetal Development of the Mammary Gland in Ways That Can Raise Breast Cancer Risk, The Endocrine Society, April 01, 2016.

Unlike typical in vitro cultures of cells, the new culture method is ex vivo, meaning that the growth of the whole mammary gland is examined outside the organism. The researchers extracted mammary buds, the early developing form of the mammary gland, from 14-day-old mouse embryos, which is a critical time for mammary development in rodents, according to Speroni. They then grew the mammary buds in culture dishes for five days. The mammary buds kept developing, allowing the investigators to observe how the mammary gland develops in real time, she said.

BPA is the first chemical the investigative team has tested using the new rapid bioassay. The study received funding from the National Institute of Environmental Health Sciences and the Art beCAUSE Breast Cancer Foundation in Framingham, Mass.

Speroni and her collaborators tested various BPA doses and compared the effects with estrogen. She said BPA increased growth of the mouse mammary bud at doses which were environmentally relevant. This effect is similar to what happened when the researchers exposed the mouse fetus through its mother in a previous study, she noted.

Many past studies have demonstrated that BPA has estrogen-like effects. However, Speroni and colleagues found that BPA did not have the same effect on the mouse mammary bud as did estrogen, which inhibited mammary gland growth. They plan to conduct more studies to learn the reason why and to try to find the mechanism by which BPA disrupts mammary gland development.

The researchers also hope to test other hormonally active chemicals that potentially cause breast cancer.

“We now have a way to test the impact of endocrine-disrupting chemicals on the development of the mouse mammary gland at different doses and obtain results in less than a week.”

Speroni said.

Chemical Exposure linked to 1.4 Billion Euros in Women’s Health Care Costs

Endocrine-disrupting chemicals may raise risk of developing endometriosis, uterine fibroids

Washington, DC – Endocrine-disrupting chemicals may contribute to reproductive health problems experienced by hundreds of thousands of women, costing European Union an estimated €1.4 billion ($1.5 billion) a year in health care expenditures and lost earning potential, according to a new study published in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism, Female Reproductive Disorders, Diseases, and Costs of Exposure to Endocrine Disrupting Chemicals in the European Union.

Chemical Exposure Linked to 1.4 Billion Euros in Women’s Health Care Costs, The Endocrine Society, March 22, 2016.

The study examined rates of uterine fibroids – benign tumors on the uterus that can contribute to infertility and other health problems – and an often painful condition called endometriosis where the tissue that normally lines the uterus develops elsewhere in the body. The two conditions are common, with as many as 70 percent of women affected by at least one of the disorders.

Research has linked the development of uterine fibroids and endometriosis to chemicals found in pesticides, cosmetics, toys and food containers. Past studies suggest a byproduct of the pesticide DDT, a chemical known as DDE, can raise the risk of developing uterine fibroids. Another group of chemicals called phthalates, which are found in plastic products and cosmetics, have been tied to growing risk of endometriosis.

DDT and phthalates are known endocrine-disrupting chemicals (EDCs). EDCs can contribute to health problems by mimicking, blocking or otherwise interfering with the body’s hormones – the signaling system the body uses to determine how cells develop and grow. Unborn children are particularly vulnerable because exposure during key points in development can raise the risk of health problems later in life.

“The data shows that protecting women from exposure to endocrine-disrupting chemicals could substantially reduce rates of disease and lower health care and other social costs of these conditions”

said Leonardo Trasande, MD, MPP, Associate Professor of Pediatrics, Environmental Medicine & Population Health at NYU Langone Medical Center.

Female Reproductive Disorders, Diseases, and Costs of Exposure to Endocrine Disrupting Chemicals in the European Union, Endocrine Society,, March 22, 2016.

The study is part of a series of economic analyses that found endocrine-disrupting chemical exposure may be costing the European Union upwards of €157 billion ($173 billion) a year. Prior studies in the series examined the costs associated with infertility and male reproductive dysfunctions, birth defects, obesity, diabetes, cardiovascular disease, and neurobehavioral and learning disorders.

To assess the economic burden of EDC exposure, a group of scientists convened a panel of global EDC experts to adapt existing environmental health cost models, relying on the Institute of Medicine’s 1981 approach of assessing the contribution of environment factors in causing illness. Based on the body of established literature, the researchers evaluated the likelihood that EDCs contributed to various medical conditions and dysfunctions.

Researchers only considered endometriosis and uterine fibroids in the analysis because there is robust data on their incidence and association with endocrine-disrupting chemical exposure. The researchers estimated that 145,000 cases of endometriosis and 56,700 cases of uterine fibroids in Europe could be attributed to exposure to endocrine-disrupting chemicals.

“Although these two gynecological conditions affect millions of women worldwide, we recognize that this analysis only reflects the tip of the iceberg,” “A growing body of evidence suggests EDC exposure is linked to a broader range of female reproductive problems, including polycystic ovary syndrome, infertility and pregnancy complications. These disorders also place a significant cost burden on women, their families and society as a whole.”

Trasande said.

The economic analysis included direct costs of hospital stays, physician services, and other medical costs. The researchers also calculated estimates of indirect costs such as lost worker productivity associated with these often painful disorders.

Soy-rich diet linked to improved success of infertility treatments among EDCs-exposed women

Eating Soy May Protect Women from Health Risks of BPA

Consuming soy regularly may protect women who are undergoing infertility treatments from poor success rates linked to bisphenol A exposure, according to a new study.

Eating Soy May Protect Women from Health Risks of BPA, The Endocrine Society,  January 27, 2016

Bisphenol A (BPA) is a chemical found in a variety of food containers, including polycarbonate plastic water bottles and can linings. BPA can mimic estrogen, one of the two main sex hormones found in women. Biomonitoring studies by the U.S. Centers for Disease Control and Prevention estimate that more than 96 percent of Americans have BPA in their bodies.

As of 2014, nearly 100 epidemiological studies have been published tying BPA to health problems, including reproductive disorders, according to the Society and IPEN’s Introduction to Endocrine-Disrupting Chemicals.

“Our study is the first to show a possible interaction between soy and BPA in humans. This is consistent with research in mice that found a soy-rich diet could protect against reproductive health problems associated with BPA exposure. More research is needed to determine why soy has this effect in humans.”

said the new study first author Jorge E. Chavarro, MD, ScD, of Harvard T.H. Chan School of Public Health, Brigham and Women’s Hospital, and Harvard Medical School in Boston, MA.

The researchers examined the relationship between BPA exposure, diet and success rates among 239 women who underwent at least one in vitro fertilization (IVF) cycle at the Massachusetts General Hospital Fertility Center between 2007 and 2012. The women participated in the Environment and Reproductive Health (EARTH) Study, an ongoing prospective cohort study designed to evaluate the role of environmental factors and nutrition in fertility. The EARTH Study was funded by the National Institutes of Health’s National Institute of Environmental Health Sciences.

Soy Intake Modifies the Relation Between Urinary Bisphenol A Concentrations and Pregnancy Outcomes Among Women Undergoing Assisted Reproduction, JCEM, January 27, 2016.

Participants’ urine samples were analyzed to measure BPA exposure. The women, who were between the ages of 18 and 45, completed a lifestyle questionnaire that included questions about how frequently they ate soy-based foods. Among the participants, 176 consumed soy foods.

Among women who did not eat soy foods, those with higher levels of BPA in their urine had lower rates of embryo implantation, fewer pregnancies that progressed to the point where the fetus could be seen on an ultrasound, and fewer live births than women with lower levels of BPA in their bodies. In comparison, BPA concentrations had no impact on IVF outcomes in women who routinely ate soy.

“Although it is recommended that women trying to get pregnant reduce their exposure to BPA, our findings suggest that diet may modify some of the risks of exposure to BPA, a chemical that is nearly impossible to completely avoid due to its widespread use,”

said senior author Russ Hauser, MD, ScD, MPH of Harvard T.H. Chan School of Public Health, Massachusetts General Hospital, Harvard Medical School in Boston, MA.

“Additional research could help identify other diet and lifestyle changes that may modify the effects of not only BPA exposure, but also exposure to other chemicals. In order to fully appreciate risks to human health, we need to design studies that adequately assess both diet and environmental chemical exposures.”

first author Jorge E. Chavarro added.

Parents’ exposure to chemicals prior to conception linked to child’s health problems

Life-Long Implications of Developmental Exposure to Environmental Stressors

image of severe-weather
A couple’s exposure to endocrine-disrupting chemicals, psychological stress, malnutrition, and other environmental stressors prior to conceiving a child may alter the child’s genetic structure and development, leading to increased risk of health issues later in life, according to a study led by Philippe Grandjean, adjunct professor of environmental health at Harvard T.H. Chan School of Public Health and professor of environmental medicine at the University of Southern Denmark.

Parents’ Preconception Exposure to Environmental Stressors Can Disrupt Early Developmental Processes, Endocrine Society, August 04, 2015.

Even before a child is conceived, the parents’ exposure to environmental stressors can alter the way genes are expressed and ultimately harm the child’s health when those genes are passed down to the next generation, according to a new article published in the Endocrine Society’s journal Endocrinology.

Exposure to environmental stressors such as endocrine-disrupting chemicals, psychological stress and malnutrition may result in disadvantageous epigenetic “reprogramming” that can echo through multiple generations.  When these stressors disrupt early developmental processes, they may cause changes in cellular gene expression, cell numbers or locations of cells that persist and lead to increased risk of cognitive disorders, obesity, diabetes and metabolic diseases later in life.

The article summarizes key insights from the 4th Conference on Prenatal Programming and Toxicity (PPTOX IV). More than 300 people attended the event in Boston, MA in October 2014. The meeting featured more than 60 oral and 130 poster presentations discussing the impact of chemical, physical and biological environmental stressors on the interconnected relationships of endocrine, immune and nervous systems.

Previous research on environmental stressors focused primarily on exposures during pregnancy and early childhood and their effects on the health of the offspring across the lifespan. However, presentations at PPTOX IV emphasized that the preconception period in both females and males is also a sensitive developmental window.

In regard to environmental stressors, a good start lasts a lifetime,” said Philippe Grandjean, MD, PhD, Professor of Environmental Medicine at the University of Southern Denmark and Adjunct Professor of Environmental Health at the Harvard T.H.Chan School of Public Health and an author of the article. “Unfortunately, current testing paradigms do not properly assess the impact of risk factors during vulnerable exposure windows. Without new policies and guidelines, we cannot have a universal healthy start for children.”

Researchers note that regulatory agencies currently may not appropriately take into account the potential for non-linear effects of certain environmental chemicals, meaning that exposure to low levels of a chemical can have different adverse effects than what could be experienced at exposure to higher levels of the same chemical.

The conference also highlighted the importance of placental function and the need to understand how changes in placental status may affect fetal development, as well as the importance of mixed stress exposures.

More information
  • Developmental Origins of Health and Disease: Integrating Environmental Influences, endocrine, August 04, 2015.
  • Life-Long Implications of Developmental Exposure to Environmental Stressors: New Perspectives, endocrine, August 04, 2015.
  • List of Endocrine Disrupting Chemicals articles by The Endocrine Society.


Circulating Sex Hormones and Risk of Uterine Fibroids

Hormone plays previously unrecognized role in common fertility problem

image of estradiol
Elevated testosterone and estrogen levels may raise risk of uterine fibroids. test by outcast104.

Women who have high levels of both testosterone and estrogen in midlife may face a greater risk of developing benign tumors on the uterus called uterine fibroids than women with low levels of the hormones.

2015 Study Abstract

Estrogen has been implicated in the development of uterine fibroids. However, the contribution of androgen in women is unknown.

Our objective was to assess the longitudinal relations of circulating androgens and estradiol (E2) and their joint effects to the risk of developing fibroids.

This is a 13-year longitudinal study in the Study of Women’s Health Across the Nation.

This study was conducted in seven sites across the United States (1997–2013).

At baseline, 3240 pre- or early peri-menopausal women with an intact uterus, ages 45–52 years were included; 43.6% completed the follow-up. There were 512 incident and 478 recurrent fibroid cases.

We measured near-annual time-varying serum levels of bioavailable E2 and bioavailable T, dichotomized at the median (high vs low).

Main Outcomes and Measures:
We estimated the conditional odds ratio (OR) of fibroids in the ensuing year using discrete-time proportional odds models adjusted for race/ethnicity/site, age, body mass index, menopausal stage, reproductive factors, smoking, timing of blood draw, and FSH.

Women with high T had a statistically significant increased risk of incident fibroids (OR, 1.33; 95% confidence interval [CI], 1.01–1.76; P = .04), but not recurrent fibroids. This risk was further elevated in those with high T and E2 (OR, 1.52; 95% CI, 1.07–2.17; P = .02). High E2 and T was associated with lower risk of recurrent fibroids (OR, 0.50; 95% CI, 0.26–0.96; P = .04).

High T with high E2 was associated with an elevated risk of incident fibroids in midlife women who never reported fibroids before baseline. Conversely, the risk of recurrent fibroids was mitigated in women with high E2 and high T.

Sources and more information
  • Elevated Testosterone Levels May Raise Risk of Uterine Fibroids, Endocrine Society, December 15, 2015.
  • Circulating Sex Hormones and Risk of Uterine Fibroids: Study of Women’s Health Across the Nation (SWAN), Endocrine Society,, December 15, 2015.

Endocrine-Disrupting Chemicals: 2nd Endocrine Society Scientific Statement

The Endocrine Society, Hormone Science to Health, 2015

EDC2 PDF image
In 2015, The Endocrine Society made a number of recommendations For and Beyond Research Over the Next 5 Years.

The past 5 years represent a leap forward in our understanding of EDC actions on endocrine health and disease. The scientific literature published during this period has provided much deeper insights into the underlying molecular and cellular mechanisms of action, the importance of critical developmental exposure periods, and stronger epidemiological studies in humans from around the world. Despite limitations due to differences in experimental design in cell and animal studies and the need for caution in inferring causality from epidemiological work in humans, most studies support links between exposure and adverse outcomes.

Recommendations for Research Over the Next 5 Years
– Mechanistic studies of EDC actions on nuclear hormone receptors need to be extended beyond ERs, AR, PR, GR, ThR, and PPARs to other nuclear hormone superfamily members and to membrane steroid hormone receptors.
– Investigate EDC effects on enzymes involved in steroidogenesis, hormone metabolism, and protein processing in humans and animal models.
– Consider tissue-specific effects of EDCs.
– Translate research from rodents into nonhuman primates, sheep, and other species; and take advantage of transgenic (especially humanized) animals, keeping in mind the need for a better understanding of hormones and early-life development in humans.
– Test additional critical periods beyond prenatal and early postnatal—eg, adolescence as an additional sensitive developmental window.
– Evaluate EDC outcomes at different life stages–not just adulthood.
– Design studies to consider sex and gender differences in response to EDCs.
– Perform longitudinal and multigenerational analyses in animals and humans.
– Evaluate and implement emerging and sensitive testing systems, including highthroughput systems, for hazard assessment, screening, and prioritization.
– In humans, consider genetic diversity and population differences in exposures and outcomes. This should include racial, ethnic, socioeconomic, and geographic variables.
– Expand research to emerging “EDCs of interest” and to mixtures of low-dose EDCs.
– The team science approach, including teams of basic, translational, and clinical scientists; epidemiologists; health care providers; and public health professionals, needs to be a priority for future research and funding.

Recommendations Beyond Research for the Next 5 Years
– Educate the public, the media, politicians, and governmental agencies about ways to keep EDCs out of food, water, and air and to protect developing children, in particular.
– Develop industrial partners such as “green chemists” and others who can create products that test and eliminate potential EDCs.
– Recognize that EDCs are an international problem and develop international collaborations.
– Cultivate the next generation of EDC researchers, green chemists, physicians, and public health experts with expertise in endocrine systems.
– Funding agencies need to go beyond the “one scientist, one project” and “one clinician, one patient” perspective to fund team science and healthcare.
– Funding agencies need to prioritize EDC research in the basic, clinical, and epidemiological realms, especially considering that the cost of research and prevention will result in substantial cost savings in treatment and mitigation.
– Emphasize the need for precaution and prevention.
– Determine how much evidence is enough, based on rigorous, peer-reviewed science—keeping in mind that absolute proof of harm, or proof of safety, is not possible.

Accepted: September 2, 2015 – First Published Online: November 6, 2015.

Sources and more information
  • Flickr album DES and EDCs Research.
  • EDC-2: The Endocrine Society’s Second Scientific Statement on Endocrine-Disrupting Chemicals, DOI: 10.1210/er.2015-1010, November 06, 2015.
  • Executive Summary to EDC-2: The Endocrine Society’s Second Scientific Statement on Endocrine-Disrupting Chemicals, DOI: 10.1210/er.2015-1093, September 28, 2015.
  • Endocrine-Disrupting Chemicals: An Endocrine Society Scientific Statement, NCBI PMCID: PMC2726844, doi: 10.1210/er.2009-0002, June 2009.