This excerpt is published with permission from the author. Find the full post on The Pump Handle.
Dick Clapp, CHE Partner
Between 1940 and 1971, a synthetic form of estrogen called diethylstilbestrol (DES) was prescribed to pregnant women to prevent miscarriage and premature labor. This practice changed abruptly, though, after the New England Journal of Medicine published a dramatic new finding from a study of young women diagnosed with a rare cancer in two Boston hospitals. The authors of the study, using a hospital-based matched case-control design, reported a startling excess of clear cell adenocarcinoma of the vagina in women whose mothers had taken DES to prevent pregnancy loss. Seven of the eight cases were born to mothers who were prescribed and took DES during their pregnancy, while none of the mothers of the controls had taken the drug.
The probability of this outcome was estimated as less than 0.00001; although not reported in the published article, the odds ratio would have been infinity. Given the rarity of this cancer, and the strength of the association reported in this careful study, this result was so convincing that an accompanying editorial in the same issue of the journal said “it seems prudent for physicians to use caution in prescribing estrogenic substances during pregnancy.” This cautionary language was putting physicians on notice that prenatal exposure to DES appears to cause cancer in offspring. Later the same year, the U.S. Food and Drug Administration issued a Drug Bulletin for physicians saying the prescription of the drug was contra-indicated during pregnancy.
Read more on The Pump Handle blog.
In recognition of CHE’s 10th anniversary, colleagues who have been particularly instrumental to shaping CHE this past decade will be invited to write an introduction. This month’s introduction is by Nancy Hepp, MS, CHE’s Research and Communications Specialist.
Many years ago, I heard Paul Harvey on the radio describe two women, typical housewives, who were each cleaning their bathtubs with an ammonia-based product. Both women were unsatisfied with the level of sparkle that they achieved and decided to add some chlorine bleach to the process. One woman spent a long time in the hospital recovering from the damage that the combination of ammonia and chlorine inflicted on her. The other woman wasn’t so lucky, according to Harvey. He described how warning labels on ammonia and chlorine products warn against mixing the two, but these women hadn’t read the labels thoroughly. I thought, “I’m sorry for these women and their families, and I wish they had read the labels more thoroughly.” I didn’t think, “These products shouldn’t be in our stores and our homes.”
Then in the late 1980s I was living in Germany and discovered that the Germans were far ahead of the US in recycling and toxic waste awareness. Signs at the garbage dump instructed me to separate out not only recyclables but also hazardous materials from my trash—something I’d never done before. I read the long list of materials that were too hazardous to dispose of in a landfill: paints and batteries, of course, but also pesticides and laundry detergents (even the empty bottles that had residues), cosmetics, household cleaners…products I used every day. I thought “These Germans sure are picky.” I didn’t think, “Why are cleaning products and cosmetics considered hazardous waste? These products shouldn’t be in our stores and our lives.”
The Collaborative on Health and the Environment initiates a quarterly Top 10 series with this offering of journal articles, news stories, policy recommendations and actions from the last few months.
Given that we all are inundated with dozens of stories—often compelling new science and ideas—every week, if not every day, discerning which ones seem most significant and influential is challenging. This is why we decided to start this service—to help us all figure out which ones seem particularly important to track over time.
Though choosing a “Top 10” is more of an art than a science, we selected these items because we consider them “game-changers” in one way or another: they all have had a significant impact, or are likely to have a significant impact on thinking and action in the field; they’ve changed the conversation on a topic or expanded the scope of the conversation to a new audience or awareness; and/or they are likely to be pivotal in defining a new trend. We have also listed some that reflect a high level of energy and activity in a particular arena. Though the science may still be relatively new or controversial, the level of focus suggests it is worthy of our attention.
We realize articles in addition to the ones we selected could arguably be included. We also may have missed some new publication or story that, in retrospect, will appear to be seminal. We invite comments and look forward to a rich conversation around this.
Finally, we have chosen to focus on stories instead of issues. There are many additional issues of great importance than we could have captured in this brief analysis, but these are the stories we believe are currently making an impact on environmental health thinking and conversations, both for professionals and for the general public.
CHE intends to publish our next quarterly Top 10 in mid January 2013.
Now for this first Top 10, in no particular order:
- Chicago Tribune series on flame retardants
CHE selected this story series because the depth of the investigative reporting was impressive, the conversation as a result of the series was far-reaching (Watchdog Update: Pressure grows for limits on flame retardants), and the repercussions have been significant:
- California is reconsidering its 37-year-old regulation on flammability in sofas, easy chairs and baby products in homes (Key agency moves to scrap rules that made toxic flame retardant common in U.S. furniture);
- Bipartisan support has emerged for national restrictions on flame retardants (see Changes in chemical safety law getting bipartisan support and Legislators urge ACC to expel firms);
- The EPA has promised to look at banning harmful flame retardants (EPA vows investigation of flame retardants, which Tribune investigated and EPA identifies substitutes for toxic flame retardant chemical); and
- The Senate passed the Safe Chemicals Act out of committee (Historic vote: oversight of EPA authorities and actions to control exposures to toxic chemicals). Similar bills have been introduced many times over the last dozen years or more, but this is the first time it passed out of committee. While there is no stated connection between the Tribune series and the Senate vote, the news series appeared to elevate general national conversation around chemical regulation, and all of the individuals who testified as part of the Senate hearing specifically mentioned flame retardants in their testimony.
- Endocrine-disrupting chemicals and public health protection: a statement of principles from the Endocrine Society
This position statement from a major medical society guides research and regulation of chemicals that disrupt endocrine function and interfere with the function of other biological systems in the human body. In the paper, the Endocrine Society proposes a simplified definition of an endocrine-disrupting chemical (EDC) as an exogenous chemical or mixture of chemicals that interferes with any aspect of hormone action. The position statement also lays out recommendations for more protective regulation of EDCs including addressing low-dose effects of EDCs.
- Experts say protocols for identifying endocrine-disrupting chemicals inadequate
- Hormones and endocrine-disrupting chemicals: low-dose effects and nonmonotonic dose responses
- International Workshop: Low Dose Effects and Non-Monotonic Dose Responses for Endocrine Active Chemicals: Science to Practice, held in Berlin September 11 – 13, 2012
Heightened attention has been given to scientific studies and news stories in the US and in Europe regarding health and safety concerns around hydraulic fracturing, commonly known as fracking. Of particular concern is the negative repercussions fracking can have on the quality of our drinking and irrigation water, for air and soils, for human health and regarding earthquakes and climate change. See, for example:
- Impacts of gas drilling on human and animal health
- Polluted water fuels a battle for answers
- Nurses promote healthier energy choices
- There goes paradise
- ‘Fracking’ could get UK approval
- Fracking: boom or doom
- Fracking poses risk to water systems, research suggests
- Unconventional natural gas development and infant health: evidence from Pennsylvania
- The fracking of Rachel Carson
- Three studies from the European Commission on environmental impacts and risks of energy resources.
CHE applauds this ongoing discussion, the continued investigation of adverse effects, and the spotlight on public health and safety.
- Environmental Justice, led by a series published by Environmental Health news (EHN)
As Marla Cone, editor-in-chief of Environmental Health News, stated in an interview about the series, the reporters were instructed “to give their stories a strong sense of place and a compelling voice of the people—but also to be well grounded in the science.” As a result, this series is not only piercing and thought-provoking, documenting “the triple whammy of race, poverty and environment converging nationwide to create communities near pollution sources where nobody else wants to live”, but also prescient. Published two months before the Chevron refinery explosion in Richmond, California, the first article quotes a resident of North Richmond: “People still wonder when the next big accident is going to happen.” It happened on August 6th. The community was not taken by surprise, and there are many, many similar communities throughout the country wondering when, how and how much they will be impacted by neighboring factories, refineries, waste dumps, transmission lines and other toxic sites. A related article, Slow and underfunded, EPA program falls short in toxic site cleanups, also addresses many of the same core problems, as applied to brownfields. These quotes from this article sum up CHE’s reason for this selection: “The shortcomings are due to limited funds, a lack of federal oversight, seemingly endless waits for approvals and dense bureaucratic processes that make it difficult for poor and sparsely populated neighborhoods to compete against larger and middle-class communities that have the means to figure them out, an investigation by six nonprofit newsrooms has found… As a result, poor Americans are both more likely to live with polluted sites and less likely to be able to attract a means to turn them around, despite the existence of the brownfields program.”
- Studies of transgenerational effects of chemical or nutritional exposures in laboratory animals, in all likelihood acting through heritable epigenetic mechanisms. This is a relatively new field of research that is gaining a lot of traction. The science is still evolving, with many studies needing to be replicated and consensus reached regarding the methodology. However, several recent studies show apparent passing of traits and effects down one or more generation without DNA mutation, such as through heritable DNA methylation changes. Although further research is necessary to confirm these effects in animals, to determine the real-world implications in humans, and to better understand the mechanisms involved, these epigenetic effects provide greater reason for reducing or eliminating toxic environmental exposures in our lives.
- High-fat or ethinyl-oestradiol intake during pregnancy increases mammary cancer risk in several generations of offspring
- Epigenetic transgenerational inheritance of altered stress responses
- Environmentally induced epigenetic transgenerational inheritance of ovarian disease
- Transgenerational actions of environmental compounds on reproductive disease and identification of epigenetic biomarkers of ancestral exposures
- Gestational exposure to bisphenol A produces transgenerational changes in behaviors and gene expression
- Dioxin (TCDD) induces epigenetic transgenerational inheritance of adult onset disease and sperm epimutations
- Father’s health and exposures contribute to a child’s health and development
The idea that the effects of a father’s exposures before or close to the time of conception can affect the health of the child is building evidence, as in this article: Father’s occupation can affect health of newborn. It’s been accepted for decades that the mother’s exposures, health status and environment can affect fetal growth and development, but the idea that a father’s exposures before and around the time of conception may alter the baby’s health and development is much more recent. This study found a correlation between the father’s occupation and birth defects. While not designed to determine a causal relationship, this is a step toward identifying the contributions of the father’s exposures to fetal health. Also see
- The study referenced in the article: Paternal occupation and birth defects: findings from the National Birth Defects Prevention Study
- Why fathers really matter
- Rate of de novo mutations and the importance of father’s age to disease risk and a CHE commentary on this study: Paternal age, de novo mutations and autism risk
- American Thyroid Association (ATA) issues policy statement on minimizing radiation exposure from medical, dental diagnostics
While some risks of diagnostic medical radiation exposures have been acknowledged for decades, there has generally been an assumption that the benefits of diagnostic exposures outweigh the risks. New thinking is challenging that assumption. The American Thyroid Association’s policy statement formalizes concern that has been growing about the cumulative risks of exposures and about the increasing use of alternate technologies such as computed tomography, in this case as related to the thyroid gland. “Increased radiation exposure among both children and adults is of primary concern to the ATA because the thyroid gland is among the most susceptible sites of radiation-induced cancer,” said Dr. Elizabeth Pearce, a member of the Board of Directors of the American Thyroid Association. See also the statement: Policy Statement on Thyroid Shielding During Diagnostic Medical and Dental Radiology and Medical radiation soars, with risks often overlooked.
- CDC updates guidelines for children’s lead exposure
This change from the Centers for Disease Control and Prevention (CDC) follows several years of advocacy from environmental health researchers. It is at least the fourth time the CDC has lowered the acceptable blood-lead level since 1975 in response to new evidence that ever-lower exposures continue to harm health and development. The acknowledgement that exposures considerably lower than the previous acceptable level—10 micrograms per deciliter (µg/dL)—cause cognitive impairment and other adverse health outcomes will help alert parents and health professionals that screening and corrective action are necessary. The CDC has now set the reference level at 5 µg/dL and will re-evaluate it every four years. See also New health issues tied to low-level lead exposure, describing evidence that even very low levels of exposure to lead are associated with kidney damage and hypertension in adults and hearing impairment, reduced growth and delayed onset of puberty in children.
- ACOG District IX Clinicians’ Guide
This clinician’s guide is the first document produced by an American Congress of Obstetricians and Gynecologists (ACOG) regional office recommending that physicians screen patients for environmental exposures, provide anticipatory guidance on risk reduction, and become involved in health policy. CHE views having a major medical society regional office, especially a society focused on pregnant women and infant development, formally recommend environmental health screenings is a tremendous step forward.
- Preventing dementia: two new lines of research
Combined, these new approaches represent a sea change from past years that there was nothing individuals could do to prevent dementia.
- Exercise and dementia: four new studies
Quite a number of recent studies show that exercise can affect cognitive function late in life. From first assuming that there was no way to prevent dementia, we came to think that exercising your brain will keep it fit. Now evidence shows that exercising your body may also keep your brain fit. This is a breakthrough for improving quality of life for seniors and their families.
- Insulin resistance and Alzheimer’s disease
See, for example, Can Alzheimer disease be a form of type 3 diabetes?, Link between metabolic disorders and Alzheimer’s disease examined, Link between brain insulin resistance, neuronal stress in worsening Alzheimer’s disease and a collection of journal articles from the Journal of Alzheimer’s Disease, plus a study showing a link between glucose control and dementia (but not necessarily Alzheimer’s): Diabetes, glucose control, and 9-year cognitive decline among older adults without dementia. All these studies add to the conversations about Alzheimer’s and dementia an understanding of the role of food, nutrition and insulin in cognitive well being. If insulin resistance does play a role in Alzheimer’s, further possibilities for preventive action and treatment may be possible, since insulin resistance can be influenced by nutrition, obesity, environmental chemical exposures, exercise and more.