Science & Environmental Health Network and
the CHE and SEHN Cumulative Impacts Project
The public health consequences of large-scale natural gas extraction by hydrofracturing are all but unstudied. Regulation and permitting has been left to the states because Congress has exempted the process from regulation under the Clean Air and Clean Water Acts. States have all but ignored public health consequences in permitting decisions. And given the protection of formulae for fracking fluids as confidential business information, gauging present and potential health effects is extremely challenging.
Nevertheless, two scientists, Michelle Bamberger and Robert E. Oswald, have issued a preliminary study of what scientists might learn if they could conduct thorough analyses of the health impact of fracking. Their study, Impacts of Gas Drilling on Human and Animal Health, was published in New Solutions, Vol. 22(1) 51-77, 2012 and may be accessed on the Cumulative Impacts Project website.
In this extremely interesting article, Andrew Weil—America’s foremost integrative medicine physician—takes on the complex issue of hormesis. For those who follow CHE science dialogue closely, hormesis is controversial within the CHE community. Leading experts on EDCs are frequently suspicious of hormesis and point to industry funding for hormesis research. Weil takes a different tack, acknowledging that hormesis science may be valid but warning vigorously against its abuse. His last three paragraphs tell the story (emphasis added). Read the full article.
“In a larger sense, hormesis may help explain why people who lead strenuous lives with plenty of moderate physical challenges may be healthier and live longer than those in more comfortable circumstances. A 2008 paper titled “Hormesis in Aging” by researchers from the Laboratory of Cellular Aging, Department of Molecular Biology, University of Aarhus in Denmark concluded that “single or multiple exposure to low doses of otherwise harmful agents, such as irradiation, food limitation, heat stress, hypergravity, reactive oxygen species and other free radicals have a variety of anti-aging and longevity-extending hormetic effects.”
“All of which suggests that one of the best routes to health is to make yourself a little uncomfortable now and then. The most profitable discomforts are likely those with which human beings have a long evolutionary history such as physical exertion, getting hungry, regularly tipping back a modest measure of alcohol, short-term exposure to cold or heat, and so on. Conversely, novel stressors—such as the stew of noxious synthetic chemicals in the modern environment with which we have no evolutionary history—are best regarded as guilty until proven innocent.
Which brings up a word of caution: Throughout history, irresponsible politicians and commentators have cited the hormetic effect to justify reducing restrictions on pollution—claiming that a little poison or radiation in the water, air or food supply is good for us. This is dangerous nonsense. Hormesis appears to be of value only when dosages are very carefully controlled, which does not describe releasing random mixtures of toxins, especially synthetic ones, into general circulation. There’s still a great deal we don’t understand about hormesis. Until we do, the smartest policy for governments and industry is to keep the public’s exposure to environmental toxins as low as possible.
CHE Diabetes-Obesity Spectrum Working Group Coordinator
CHE’s January 19th call was on the interactions between gut microbiota and environmental chemicals in diabetes and obesity, a new area of research. Separately, gut microbiota and environmental chemicals may both contribute to the development of diabetes and obesity; what about the effects in combination?
The presenters reviewed research that shows that gut microorganisms can affect the absorption, distribution, metabolism, and elimination of environmental chemicals. For example, gut microbiota can cause a leaky gut, increasing absorption of chemicals. Gut microbes can modify polyaromatic hydrocarbons (PAHs) to turn them into estrogenic compounds. Microbiota can also affect detoxification processes in the liver.
An individual’s gut microbes may affect the rate at which they clear chemicals from their body. Seventy five percent of diabetogenic and obesogenic chemicals can be metabolized by gut microbes.
The interactions between gut microbiota and environmental chemicals may be significant not only for diabetes and obesity, but also for other diseases as well. It is a topic sure to see more research in the future.
To access slides and papers, visit the call page.
Philip R. Lee, MD
Former United States Assistant Secretary of Health; Chancellor of the University of California at San Francisco; Professor of Social Medicine (Emeritus), Department of Medicine; and Senior Advisor for the Philip R. Lee Institute for Health Policy Studies, School of Medicine, UC San Francisco
One fast decade ago, in early 2002, an invited group of about forty leaders from diverse disciplines met at the San Francisco Medical Society to talk about what might be done to improve research, education, practice and more in the broad field of environmental health. Some were longtime friends and colleagues and some were meeting one another for the first time. Various plans were made, but the most important result of that gathering was the organization and network we all know as CHE—the Collaborative on Health and the Environment.
I was honored to co-chair that first meeting and to serve as CHE’s Chairman since then. CHE was a somewhat amorphous concept, a vehicle for fostering closer links between scientists, clinicians, patients, advocates, and others concerned with—and impacted by—environmental factors including but not limited to chemicals in our environment and bodies. A small core group of committed people took on the varied tasks of building this concept into something more tangible, hopefully with varied positive impacts.
Ted Schettler MD, MPH
Science Director of CHE
and the Science and Environmental Health Network
Vitamin D plays an essential role in a number of biologic processes throughout the body. In addition to its long-recognized importance for bone health, vitamin D deficiency is increasingly acknowledged to be associated with a number of other diseases and disorders, including various kinds of cancer. A recently published study adds considerable support to yet another health impact—earlier age of menarche in otherwise healthy girls. If this finding holds up in future studies, the implications are profound.
If sunlight exposure is sufficient, adequate amounts of vitamin D are synthesized in the body. But many people, particularly those living in higher latitudes, are not exposed to enough sunlight to generate adequate stores. And, even in sunny places, skin cancer concerns limit sun exposure. Some foods are fortified with modest amounts of vitamin D in an attempt to address the deficiency. Nonetheless, vitamin D insufficiency remains extremely common in the general population. A recent report from the Institute of Medicine addresses this.