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Medicine for the Outdoors

Dr. Paul Auerbach is the world's leading outdoor health expert. His blog offers tips on outdoor safety and advice on how to handle wilderness emergencies.

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Outdoor Medicine and the Environment Redux

Earlier this year, I published a series of three posts based upon a commentary I wrote, entitled "Physicians and the Environment," that was published in the Journal of the American Medical Association. The commentary was an invited piece, and reflected some of my thoughts about current environmental issues and the role of the medical profession in achieving the education necessary to be able to intelligently respond to these issues. Recently, the AMA issued a statement supporting many of the concepts I presented in my commentary. Since that announcement, I’ve received numerous requests from readers of this blog to combine the posts into a single offering, which I offer here.

This post uses parts of my original commentary in JAMA to put this issue into context for the layperson, and so I am including the references where appropriate from the original commentary.

There is every reason for persons involved and interested in wilderness and outdoor medicine to be advocates for preservation of the environment. The entire concept of "wilderness medicine" is predicated upon the existence and improvement of wilderness areas, which are among the most pressured and rapidly receding parts of planet Earth.

In many circumstances in the past, the medical profession has responded to adverse situations of global reach, such as epidemic diseases, genocide, the threat of nuclear war and natural disasters. As the world’s scientists, governments, and businesses now confront the state of the environment, all manner of health care professionals also must be prepared to respond, because in the final analysis, health matters are integral to the predicament, predictions and discussion. Beyond being just a reliable resource, given the magnitude and complexity of issues as they relate to human health, the medical profession should accept the challenge of becoming a leader in the discussions and debates.

Despite our preoccupation with armed conflicts and the economy, the environment is perhaps today’s most pressing global issue, as it contributes not only to direct effects, but to other situations of concern, such as economic decline and civil disobedience. Environmental conditions contribute to the presence or intensity of many medical conditions, such as temperature-related morbidity and mortality, health effects of extreme weather events (e.g., storms, floods, tornadoes, hurricanes, and precipitation extremes) and their sequelae (e.g., oceanic algae blooms), ecological change (e.g., the potency of certain harmful plants, such as poison oak), starvation, allergies, pollution-related health effects, water- and food-borne diseases, and vector- and rodent-borne diseases.1,2

As we learn more, it becomes apparent that the full eventual effects of global climate change and other environmental issues are not necessarily easily defined or well predicted. There are multiple views surrounding every issue. Some of the most important issues that need to be continuously examined from every angle include global warming, depletion of stratospheric ozone and increases in ground-level ozone, destruction of forests, polar melting, deficiencies in water production and sanitation, and human population growth and dynamics.

There are and will be significant differences of opinions about what follows here. My comments are properly interpreted as being "pro-environment" or "green," leaning toward the perspective that advocates that there are significant environmental problems and that many of these can be attributed to the activities of humans. However, I most certainly acknowledge the rights and responsibilities of others to hold different viewpoints and opinions, and the value of their being skeptical about science and conclusions. The most important thing is that we do not become acrimonious or disengaged, because it will take all of our skills of observation, analysis, and collaboration to reach consensus on these matters in a timely fashion and in a way that promotes improvement, not conflict. The acts of remediation are expensive and potentially diverting (from other problems), so no significant change should be taken lightly.

Global Warming.
Atmospheric accumulation of gases (predominately carbon dioxide, methane, nitrous oxide, and halocarbons) traps heat by the greenhouse effect.3 The Intergovernmental Panel on Climate Change predicted that average global temperature will continue to increase, and a major concern is the rate of warming.4 Compared with the century 1906-2005 required to raise the earth’s average atmospheric temperature by 0.56 degrees Centigrade, some suggest that only a decade may be needed to raise it another 0.28 degrees C.5 This rate of change has been created by burning fossil fuels in power plants and for transportation, a decline in carbon intensity reductions, and natural sinks removing a smaller proportion of emissions from the air.6 Each year, more than 1.2 cubic miles of oil, 3.5 billion metric tons of coal, and 100 trillion cubic feet of natural gas are burned worldwide, releasing 30 billion tons of carbon dioxide into the atmosphere.7 Without efforts to stabilize or decrease consumption of fossil fuels, the 14.9 billion metric tons of carbon emissions released by the United States, the European Union, China, and India in 2005 are projected to increase to 25.6 billion metric tons in 2030.8 Even if one disputes the precise numbers, we seem to be on an unsustainable spree of consumption. Is global warming due to rising carbon dioxide levels, and are these rising levels attributable to the activities of humans, or are these environmental "facts" part of a series of coincidences? We need to know the answer. How many barrels of oil, tons of coal, and cubic feet of natural gas can be extracted from the earth before we run out? At our current rates of consumption, when will this occur? We need to know the answers.

Depletion of Stratospheric Ozone. Chlorofluorocarbons and other ozone-depleting substances released into the atmosphere are major contributors to the destruction of ozone in the stratosphere. Depletion of the ozone layer exposes the earth’s inhabitants to increased amounts of harmful ultraviolet-B radiation. This contributes to skin cancer, cataract formation, suppression of the immune system, and damage to certain crops.9 This is counter-posed by accumulation of ozone at ground level, which contributes to lung disease and other health risks.

Destruction of Forests.
Fires set to clear forests for agriculture and grazing release carbon dioxide, which is a contributing factor to global warming. According to the World Bank, approximately 22 million acres of rain forests are destroyed by intentional fires each year, accounting for approximately 20% of worldwide carbon dioxide emissions.10 Wildfires, often coinciding with droughts, generate additional atmospheric carbon dioxide.11 In preindustrial times, the atmospheric abundance of carbon dioxide was relatively constant at 280 ppm; in the 1950s, the level was 300 ppm; in 2006, it had attained 381 ppm; and in 2008 it is increasing.12 At what rate are these forests being re-planted? Can men and women continue to remove habitat, plants, animals, and minerals from planet Earth at current rates and be assured that this does not pose a catastrophic future for our populations of life forms? We need to know the answers.

Polar Melting.
Consistent with the increase of global temperature, there is a loss of snow cover in the Northern Hemisphere, the amount of Arctic and Antarctic sea ice is diminishing, and glaciers are melting.13 Predictions suggest that in the next few centuries, sea levels could rise by as much as 17.8 cm to 6 m, and the Gulf Stream may be diminished or even eliminated.14 In low-lying coastal areas where populations cannot be protected by natural or artificial barriers, large numbers of climate refugees may be forced to migrate to other locations, thereby increasing population crowding. Global climate change also is predicted to contribute to flooding and fire risk; increase the intensity of cyclones (hurricanes) and heat waves; accelerate beach erosion and desertification; hasten species extinction; and diminish water and food (livestock, fish, and plants) availability.15 I have heard many arguments about animals, such as polar bears, that putatively face extinction because of hunting, habitat and climate change, loss of food supply, etc. Are important animal populations declining? Can or should we intervene in the decline of any species? What does history tell us about the effects of rising and falling sea level? We need to know the answers to these questions.

Deficiencies in Water Production and Sanitation.
Sachs16 contends that global climate change will tighten the availability of water, and force migration of hundreds of millions of individuals over the course of a few decades. According to the United Nations, more than 5 billion persons on Earth may live under severe water stress by the year 2025.17 Currently, 1.1 billion persons lack adequate water worldwide, 2.6 billion lack adequate sanitation, and 1.8 million children die each year because of one or both of these deficiencies.18 The outdoors can be beautiful, marvelous, and a tonic for the body and spirit, but it can also be a cruel, terrifying environment of forced survival. What is the true status of our water supplies, nation by nation, region by region? We need to know.

Human Population Growth and Dynamics. The human population is increasing exponentially, which has an unprecedented global effect on ecology and biodiversity. This effect takes place through overharvesting, introduction of nonnative species, pollution, and habitat fragmentation and destruction.19 As large, developing countries face increasing energy demands, they will undoubtedly burn increasing amounts of fossil fuels. The environmental conditions and climate changes that have been touted as major influences on health may potentially involve millions of individuals being injured or killed by floods, tsunamis, and cyclones; tens of millions afflicted by poorly controlled diseases that might emerge as a consequence of unchecked vectors (such as mosquitoes); hundreds of millions malnourished due to desertification, loss of crops, and insufficient potable drinking water; and ultimately, poor health and the loss of prosperity as individuals are crowded into a reduced landmass that may be too small to reasonably support their survival.20,21 The worldwide growth of the human population dramatically increases the possibility of loss of life-sustaining resource bases during large geological and weather events in a manner that limits human survival. Simply put, the more pins standing behind the lead pin when the bowling ball strikes, the more that are vulnerable to being struck down and swept away. We need to be very thoughtful about this, because hunger and economic deprivation inevitably lead to conflict and even war. So, basic human needs may trump our desire to divert crops, such as corn, to alternative fuels. We are already witnessing these effects.

While there are a wide variety of opinions about the timeline for such events, the arguments supporting environmental trends are substantiated by reasonable scientific observations.2,22 Proponents of accelerating global climate change suggest that given the rapidity of changes and their unforeseen consequences, successful adaptation would appear unlikely and unattainable. The most viable solution is to halt the inexorable assault on the environment as quickly and effectively as possible. Arguments that do not support these trends are espoused by dispassionate and intelligent individuals, who also care very much about their planet, but do not necessarily agree with the scientific conclusions indicating human-generated planetary degradation and climate change. Which faction is correct? Issue by issue, point by point, we need to know. What might be at stake are the futures of species and resources that cannot be easily regenerated, if they can be regenerated at all. On the other hand, if there are better approaches than those currently favored by environmentalists, then let them be identified and implemented.

It is increasingly the case that environmental remediation recommendations are topics of great debate, for many reasons. Some reputable authorities do not agree with the proposed causation or acuity of environmental problems. Others astutely observe that some of the solutions proposed, such as diversion of crops for alternative fuels, may contribute to hunger and economic consequences that are more disruptive than expensive fuel, or even the consumption of fossil fuels.

Because the nature and magnitude of environmental changes have only recently come to be recognized, it is difficult to predict the attribution of inevitable to natural cycles, or whether the forces of nature are becoming unbalanced. Some suggest that while human activities have an effect on climate, there is not proof that this affects global temperature. For instance, there may be years during which global temperature declines. Others acknowledge the inevitability of global climate change, but recommend adaptation or geoengineering solutions.23 Opponents of those who predict irreversible global climate change and warming argue that until the precise nature and rate of these phenomena can be established, governments and industries should be tentative and cautious about making expensive policy decisions.24 Still, others point out that by focusing attention on global warming, there is a risk of not properly addressing more important environmental and health issues.

I am increasingly convinced that persons who argue against the magnitude and timing of global climate change are not doing so out of personal interests. They truly believe that our current surge in environmentalism is an over-reaction to a situation that may not be as dangerous as has been proposed. Wherein lies the burden of proof? Is it upon the conservationists, or those who demand data to support initiation of policies and practices with wide-reaching economic consequences? I think it is a shared responsibility. Beyond the data, we must certainly act with common sense.

Certain issues seem to me to be beyond calculated inaction. Developing alternative sources to substitute for fossil fuel consumption is widely supported. How can preservation of fossil fuels be bad, unless in the preservation, man unleashes some greater hardship upon the planet or its inhabitants? We are probably not yet at the stage where we should accept starvation in Africa as a consequence of our attempts to promote ethanol production for automobile fuel, but if we do not find a solution to pumping oil into our tanks, will be be creating even greater misery downstream? Despite the fact that there is almost universal assent and agreement on many issues, politics, economics, and special interests delay progress.

I cannot speak for everyone, but I have an opinion about the response needed from the medical profession. If one believes that there are situations upon which we should soon act, significant behavioral changes will be needed to begin to reverse apparent deleterious trends. Achieving global environmental change requires public and private efforts, led by a massive educational effort that should include all institutions of higher learning, including schools of medicine. By virtue of their knowledge and experience, physicians are rightfully concerned about individual and population health. However, the germs and disease processes with which we have become familiar may not pose as great a threat as what might result from such environmental eventualities as the melting of the polar caps.

It is my feeling that the time has come to broaden what the medical profession (and in particular, those with an interest in wilderness medicine) must learn, expanding awareness by educating physicians about the best environmental science. Given the hypothetical and known links of global climate change to human health, and the increasing concern that this change is accelerating, it is our duty to become informed.

Accordingly, in response to the environmental imperatives, an educational action plan is appropriate for the medical profession. Nelson25 noted about environmental studies, “ . . . the subject matter is all-encompassing. It includes . . . the air, water, minerals, soil, forests, oceans, lakes and rivers, as well as all living things in the seas and on land, the relationship and influence of each on the others, plus economics, politics, religion, culture, and philosophy. And, although we will never know or understand more than a small fraction of the endless intricacies of nature’s works, we can comprehend and learn the general principles that should guide our conduct as a society, if we are to preserve a livable habitat. The proposition is, quite simply, that we must conduct our activities in such a way as to protect the integrity of our ecosystems and their resources. . . ”

There are several potential methods for physicians and other healthcare professionals to increase awareness and involvement with environmental issues. First, there should be courses at every level on the relationship of environmental issues to human health. To cover the principles of environmental science and related medical issues, these courses should include information on atmosphere and climate; global climate change; the relationship of climate change and weather to disease vectors and transmission; the effect of climate change on the biology and afflictions of humans, plants, and animals; methods for assessing climate-related health effects; ecology and the environment; biodiversity and human health; natural environmental hazards; causes and effects of environmental contaminants; food and water science; and the causes and effects of population growth. Courses should be prepared and reviewed for accuracy and objectivity by authoritative environmental scientists and educators, in collaboration with medical professionals.

Medical societies and special interest groups, specialty organizations, and research institutes should whenever possible engage experts to summarize the best evidence about the effects of environmental change on health and medical conditions. This continuous process should foster exchange of views that takes into account medical, social, geopolitical, economic, and cultural issues. It goes without saying that the opinions that emanate from the medical profession, or any other profession for that matter, should be science-based to the greatest degree possible. Whenever new evidence emerges, current views may need to be modified as they relate to both the environment and health implications. I think it would be terrific if medical organizations would review their missions, and determine to what extent they are willing to disseminate environmental education material to their membership. Medical organizations should encourage members to become environmentally aware, and consider creating reports and multimedia presentations on global environmental health for delivery to medical professionals, students of medicine, business, government, and the general public.

Persons with special medical knowledge should investigate environmental organizations and consider supporting them with their special expertise. When appropriate, healthcare professionals can develop specific initiatives in collaboration with environmental professionals. Moreover, medical professionals should all learn about companies that truly use environmentally sound practices in their business efforts and consider supporting them. It may not make a big difference to the environment, but if for no other reason than to begin to establish a trend, hospitals and health care practices should make reasonable efforts to become green in ways that promote effective patient care while limiting the negative effect on the environment of providing that care.

And what about the wilderness medicine community? What can a person learn and do who wants to be healthy in the outdoors? The educational goals are to be better informed, become inspired, and take action. In the countless debates that will ensue, physicians and their patients should be positioned to wisely explain the medical ramifications of environmental issues. It is time to eliminate complacency and acknowledge the common “planetary patient” for whom we all share responsibility. Through education and personal resolve, each of us should strive to be active advocates for the environment.

image courtesy of National Museum of Australia Canberra

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About the Author

Dr. Paul S. Auerbach is the world’s leading authority on wilderness medicine.