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Autism Brain Origins — Environment and Physiology Really Matter July 29, 2014

Posted by Nancy Hepp in guest commentary.
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written by Martha Herbert, PhD, MD
CHE Partner

This excerpt from Dr. Herbert’s blog is shared with her permission. Read the full post on her blog.

The recent New England Journal of Medicine paper by Stoner and colleagues, “Patches of disorganization in the neocortex of children with autism.” N Engl J Med 370(13): 1209-1219, made several important contributions to studies of postmortem tissue samples from the brains of individuals with autism spectrum disorders (ASDs).  First, the average age was much younger than the average age in previous studies.  Second, many important and technologically sophisticated measures were made.  Finally, as a result of this work, a broadly distributed pattern of brain tissue abnormalities was identified that had not been described on this scale before—namely, patches of disorganization in many areas of the neocortex (the outer layer of gray matter in the brain), though not the same from one person to the next.

The new observation of disorganized patches by itself is very important.  It poses an important challenge: how do we figure out what it means?  To do that, we need to understand the data, and also to examine the interpretations and consider alternative possibilities.

Continue reading on Dr. Herbert’s site.

Top 10 Selections: 2nd Quarter 2014 July 1, 2014

Posted by Nancy Hepp in science pick.
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These are the environmental health stories, studies and reports that we think are most significant from the last three months. Comments are invited.

  1. Global toll of pollution on health
    The scope and depth of pollution worldwide and its significant toll on health and lifespan is underscored in these new reports.

    1. WHO: Air pollution top environmental health risk: Air pollution kills about 7 million people worldwide every year and is now the single biggest environmental health risk, with more than half the fatalities due to fumes from indoor stoves. The study: 7 million premature deaths annually linked to air pollution.
    2. In developing world, pollution kills more than disease: Pollution, not infectious disease, is the biggest killer in the developing world, taking the lives of more than 8.4 million people each year, a new analysis shows. However, pollution receives a fraction of the interest from the global community. A related report: The Poisoned Poor: Toxic Chemicals Exposures in Low- and Middle-Income Countries.
    3. China and India face huge cancer burden: experts: China and India are facing a cancer crisis. Sixty percent of cancer cases in China are attributable to “modifiable environmental factors”, including smoking, water contamination and air pollution, a new report concludes. The report: Challenges to effective cancer control in China, India, and Russia
  2. Economic costs of pollution
    It’s difficult to ignore these numbers and impacts, even for those not personally touched by disease or disability.

    1. Health costs of China’s polluted air ‘up to $300 bn a year’: Premature deaths and health problems from air pollution cost China as much as $300 billion a year, an official report said, calling for a new urbanisation model for the world’s second-largest economy.
    2. Health costs of air pollution from agriculture clarified: Computer models, including a NASA model of chemical reactions in the atmosphere, were used to better represent how ammonia interacts in the atmosphere to form harmful particulate matter. The study: Hidden cost of US agricultural exports: particulate matter from ammonia emissions.
    3. The full “costs” of environmentally related disease: What do failed attempts at environmental protection cost us, in terms as wide-ranging as health impacts, lost wages, and loss of IQ? Who is most burdened by our lack of societal commitment to primary prevention? The Environmental Health Policy Institute examines these questions through the lens of important cases.
    4. Health costs in the EU—how much is related to EDCs? Exposure to food and everyday electronic, cosmetic and plastic products containing endocrine disrupting chemicals (EDCs) may be costing up to €31 billion per year in the EU. Also Economic benefits of tighter controls for endocrine disruptors outweigh hypothetical trade effects.
    5. Lead poisoning of children in Michigan costs $330 million per year: Four main categories of impact were studied and expenditures were projected for costs associated with lead contamination of children: increased health care, increased adult and juvenile crime, increased need for special education, and decline in lifetime earnings.
    6. Measuring the economic cost of environmental impacts on human health: 25 experts in air quality, health economics and environmental sciences as well as representatives of EU agencies and the civil society met in Berlin, Germany, to assess this cost and guide policy makers in reducing it by investing in prevention.
    7. Air pollution is a $1.7T health problem, OECD finds: In the 34 OECD member states, the monetary impact of death and illness due to outdoor air pollution was $1.7 trillion in 2010. Research suggests that motorized on-road transport accounts for about 50 percent of that cost. The report: The cost of air pollution: health impacts of road transport.
    8. Improving air quality in NYC would boost children’s future earnings by increasing IQ: The study is the first to estimate the costs of IQ loss associated with exposure to air pollution, and is based on prior research on prenatal exposure to air pollutants among low-income children. The study: Prenatal exposure to airborne polycyclic aromatic hydrocarbons and IQ: estimated benefit of pollution reduction.
  3. Role of environmental influences on autism
    Research continues to reveal the contribution of environment to autism spectrum disorders.

    1. Autism risk higher near pesticide-treated fields, study says: Babies whose moms lived within a mile of crops treated with widely used pesticides were more likely to develop autism, according to new research. The study: Neurodevelopmental disorders and prenatal residential proximity to agricultural pesticides: the CHARGE Study.
    2. Environment as influential as genes in autism, study says: Environmental factors are more important than previously thought in leading to autism, as big a factor as genes, according to the largest analysis to date to look at how the brain disorder runs in families. The study: The familial risk of autism.
    3. Environmental influences may cause autism in some cases, study shows: The findings shed light on why older mothers are at increased risk for having children with ASD and could pave the way for more research into the role of environment on ASD. The study: Mosaic epigenetic dysregulation of ectodermal cells in autism spectrum disorder.
  4. The scent of a man: gender of experimenter has big impact on rats’ stress levels, explains lack of replication of some findings
    Scientists’ inability to replicate research findings using mice and rats has contributed to mounting concern over the reliability of such studies. Now, an international team of pain researchers led by scientists at McGill University in Montreal may have uncovered one important factor behind this vexing problem: the gender of the experimenters has a big impact on the stress levels of rodents, which are widely used in preclinical studies. The study: Olfactory exposure to males, including men, causes stress and related analgesia in rodents. The validity of the scientific processes and the results produced must be examined if we are to rely on scientific investigation to guide policy.
  5. Stress and health
    Stress as an environmental health issue, and how it interacts with other environmental factors, provides insights into the complexity of health. The transgenerational concerns are notable.

    1. Sperm RNA carries marks of trauma: A study finds that stress in early life alters the production of small RNAs, called microRNAs, in the sperm of mice. The mice show depressive behaviors that persist in their progeny, which also show glitches in metabolism. The study: Implication of sperm RNAs in transgenerational inheritance of the effects of early trauma in mice.
    2. Chronic stress heightens vulnerability to diet-related metabolic risk: Highly stressed people who eat a lot of high-fat, high-sugar food are more prone to health risks than low-stress people who eat the same amount of unhealthy food. The study: Chronic stress increases vulnerability to diet-related abdominal fat, oxidative stress, and metabolic risk. See also New insights into chronic stress, obesity, and metabolic syndrome: further support for an ecological model of health and an integrated approach to care for more analysis.
    3. Childhood bullying involvement predicts low-grade systemic inflammation into adulthood: Although C-reactive protein (CRP) levels rose for all participants from childhood into adulthood, being bullied predicted greater increases in CRP levels, whereas bullying others predicted lower increases in CRP compared with those uninvolved in bullying.
  6. EPA on climate change
    Though the EPA’s new report and rules on carbon emissions have evoked mixed responses, this is a bold stance for the EPA on addressing climate change.

    1. EPA report shows impact of changing climate on Americans’ health and environment: The report pulls together observed data on key measures of our environment, including US and global temperature and precipitation, ocean heat and ocean acidity, sea level, length of growing season, and many others. With 30 indicators that include over 80 maps and graphs showing long-term trends, the report demonstrates that climate change is already affecting our environment and our society. The report: Climate Change Indicators in the United States.
    2. EPA unveils sweeping rules to cut carbon emissions: The US power sector must cut carbon dioxide emissions 30 percent by 2030 from 2005 levels, according to federal regulations that form the centerpiece of the Obama administration’s climate change strategy. The proposal: Clean Power Plan Proposed Rule.
    3. Supreme Court ruling backs most EPA emission controls: The Environmental Protection Agency can require greenhouse-gas controls on power plants and other large stationary sources of pollution, the Supreme Court ruled, but it said the agency went too far in claiming power to regulate smaller emitters.
  7. Exacerbation of cigarette smoking’s effects: cumulative impacts
    These studies showcase interactions of cigarette smoking with other environmental exposures.

    1. Does mortality risk of cigarette smoking depend on serum concentrations of persistent organic pollutants? Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study: The association between cigarette smoking and total mortality depended on serum concentration of PCBs and organochlorine pesticides.
    2. Lung-cancer risks sky high for smokers exposed to carcinogens: A growing body of research, including two studies under way at the University of Kentucky, shows the risk of lung cancer is much higher for smokers exposed to carcinogens such as radon, asbestos, arsenic or chromium.
  8. ‘Electrosmog’ disrupts orientation in migratory birds, scientists show
    Scientists have demonstrated that the magnetic compass of robins fails entirely when the birds are exposed to AM radio waveband electromagnetic interference—even if the signals are just a thousandth of the limit value defined by the World Health Organization as harmless. The study: Anthropogenic electromagnetic noise disrupts magnetic compass orientation in a migratory bird. See also Cracking mystery reveals how electronics affect bird migration. This study provides clear evidence of biological impacts of very low exposures to electromagnetic fields.
  9. Risk factors for breast cancer
    A number of new research studies this quarter highlight potential chemical and nutritional contributors to breast cancer.

    1. Study lists dangerous chemicals linked to breast cancer: A paper in the peer-reviewed journal Environmental Health Perspectives lists 17 chemicals to avoid and offers women advice on how to minimize their exposure. The paper: New exposure biomarkers as tools for breast cancer epidemiology, biomonitoring, and prevention: a systematic approach based on animal evidence.
    2. High fat diet sharply increases breast cancer risk, study finds: A high-fat diet increases the risk of the most common form of breast cancer by a fifth. Heavy consumption of saturated fat had an even bigger impact, raising the risk of hormone-sensitive breast cancer by 28 percent. The study: Dietary fat intake and development of specific breast cancer subtypes.
    3. Could half of all breast cancers be prevented? If girls and women of all ages adopted healthier lifestyle behaviors and the highest-risk women took preventive drugs like tamoxifen, the authors of a new report say fully half of breast cancers in the US might be avoided. The review: Priorities for the primary prevention of breast cancer.
    4. Solvents may raise breast cancer risk for some, study finds: Women who already have an above-average risk of breast cancer and who work with organic solvents, such as factory and laboratory workers working with benzene or other such chemicals, may have an even higher risk. The study: Breast cancer risk in association with occupational exposure to organic solvents.
    5. Red meat ‘linked to breast cancer’: Eating a lot of red meat in early adult life may slightly increase the risk of breast cancer. The study: Dietary protein sources in early adulthood and breast cancer incidence: prospective cohort study.
  10. Newborns exposed to dirt, dander, germs may have lower allergy, asthma risk
    Infants exposed to rodent and pet dander, roach allergens and a wide variety of household bacteria in the first year of life appear less likely to suffer from allergies, wheezing and asthma, according to results of a recent study. Those who encounter such substances before their first birthdays seem to benefit rather than suffer from them. Importantly, the protective effects of both allergen and bacterial exposure were not seen if a child’s first encounter with these substances occurred after age 1, the research found. The study: Effects of early-life exposure to allergens and bacteria on recurrent wheeze and atopy in urban children. This research is important both because of the widespread prevalence and impact of asthma and because of the new finding of the importance of timing of exposures.

“We think, therefore I am”? How the changing concept of individuality in biological sciences is influencing how we think about ourselves and our health June 11, 2014

Posted by Nancy Hepp in Newsletter introductions.
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written by Elise Miller, MEd
CHE Director

Elise MillerThe experience of teenage girls in northern India, growing up in traditional upper-caste Indian homes but being exposed increasingly to Westernization, was the focus of my graduate research 25 years ago. My particular area of interest was exploring their experience of “self” and how it impacted their choices and values. What I learned is that “I” for these girls meant something far more permeable, relational, and inclusive of other than the very individualistic concept of “I” which is so fundamental to Western thought and civilization.

As Western biological science has begun to grapple with the complex interplay of multifactorial contributors to health and disease, defining “I” or what an individual actually is has become increasingly challenging as well. Dr. Scott Gilbert, professor of biology and author of Ecological Developmental Biology, brings attention to this in his article, “A Symbiotic View of Life: We Have Never Been Individuals.” He notes that Western scientific disciplines have used a certain concept of “individual” as a basis for research since the inception of modern science. Whether the entity being studied was a lichen or a human, it was considered until very recently a distinct organism.

As more research on the microbiome and other “omes” emerges, however, our perception of what comprises an individual becomes far blurrier, and the biological interplay of symbionts and holobionts takes center stage. Like the understanding of “I” among the teenage girls in India in my own study, the biological concept of a single entity in Western science is becoming more boundary-less and relational. In fact, as Dr. Gilbert and other biologists point out, it’s increasingly clear that an organism can no longer be studied as a distinct individual. The previously assumed mono-genomic organism is conceptually wrong. Instead, we are all made of up a community of organisms, which are genomically interconnected and mutually interdependent in a variety of ways.

So what does this have to do with chemical contaminants and their impact on human health? Everything. For example, the human body (the holobiont) is made up of 90% microbes (the symbionts) each with their own metabolisms. This means that we can no longer be concerned just with how industrial compounds might disrupt gene expression in humans. Instead, if an exposure to a chemical undermines the hormonal signaling in a microbe, which we are dependent on for digestion, then our ability to digest properly is disrupted. To take this one step further, since many studies have shown how important the gut-brain axis is, our brain function may also be impaired. Along these lines, one study published recently suggested that “germ-free” mice can have autism-like symptoms, which disappear when the bacteria is put back in the mice.

If this isn’t mind-boggling enough, microbes, because they have their own metabolisms, can also influence which genes are passed on. This means, as Dr. Gilbert has purported, that they may have an evolutionary impact by selecting for genetic variations that benefit certain symbionts.

And we thought animal research was already complex enough! But now, in essence, scientists are realizing you not only have to control for the feedstock and other environmental factors in a study, but for the particular microbes within the animal being studied.

OK. I didn’t intend to offer a mini-science lecture, and I’m the last one who could speak on this with any real authority. But I personally found this so conceptually revolutionary because of its implications for our work in environmental health. This way of thinking, based on my reading of this emerging science, underscores why the impact of environmental exposures on human health may prove to be even more significant than we already thought. Not only are we concerned about the effect on an individual, but on all of the organisms within that so-called “individual” as well. In short, how we perceive “I”, as I learned from those Indian girls many years ago, shapes how we see the world and the choices we make and the value we place on relationships. Maybe as other scientific disciplines begin to take into consideration this inherent interconnectedness–something ecologists have done for so long–we may start making smarter decisions about what we put in our environment, knowing that it not only effects our health and that of future generations, but the health of everything else that makes us “us.”

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