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EXPANDING ECOTOXICOLOGY TO ENHANCE THE HEALTH OF THE BIOSPHERE. John Cairns, Jr. University Distinguished Professor of Environmental Biology Emeritus Department of Biological Sciences Virginia Polytechnic Institute and State University Blacksburg, Virginia 24061, U.S.A. March 2010.
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EXPANDING ECOTOXICOLOGY TO ENHANCE THE HEALTH OF THE BIOSPHERE John Cairns, Jr. University Distinguished Professor of Environmental Biology Emeritus Department of Biological Sciences Virginia Polytechnic Institute and State University Blacksburg, Virginia 24061, U.S.A. March 2010
THE WASTES (OUTPUT) OF MOST SPECIES IN THE BIOSPHERE SERVE AS RESOURCES (INPUT) FOR OTHER SPECIES. • This output/input cycle represents billions of years of evolution. • Nature has provided a model that has previously maintained a healthy biosphere. • More information is known now about what nurtures the biosphere and what harms it. • Wastes that harm the biosphere should be banned.
EVEN THIS MUTUALISTIC PROCESS CAN BE DISRUPTED IF THE WASTES (OUTPUT) EXCEED THE ASSIMILATIVE CAPACITY (INPUT) OF THE SPECIES IN THE BIOSPHERE. • For example, anthropogenic carbon dioxide emissions currently exceed the biospheric assimilative capacity for them, so carbon dioxide accumulates in the atmosphere and destabilizes Earth’s climate. • Humankind’s enlightened self interest requires reducing anthropogenic greenhouse gas emissions to a level congruent with biospheric assimilative capacity, but the recent climate conference in Copenhagen in December 2009 was unable to reach a consensus on goals to achieve this reduction. • If “business as usual” continues, unproven “Hail Mary” geo-engineering technologies may be used to keep the global average temperature increase below 2°C. • Time is short and the consequences of failure to control carbon dioxide emissions are catastrophic. • A major, immediate reduction of anthropogenic greenhouse gas emissions might keep the global average temperature increase below 2°C – possibly an acceptable level.
THE PRIMARY, INITIAL GOAL IN ECOTOXICOLOGY IS TO CEASE PRODUCTION OF CHEMICAL SUBSTANCES THAT CANNOT SERVE AS USEFUL INPUTS (RESOURCES) FOR THE BIOSPHERE. • Most anthropogenic wastes ([output], e.g., endocrine disruptors) are hazardous to many species (including humans) in the biosphere. • Cessation in production of chemical substances will require a major paradigm shift for factories because neither the product (e.g., pesticides) nor the wastes nurture the biosphere. • From the beginning of the Industrial Revolution, the ideal goal has been merely to do no harm to the biosphere. • One need not be a toxicologist to realize that much harm has been done by destructive output to the species that comprise the biosphere.
AFTER ELIMINATING DISCHARGES OF HARMFUL ANTHROPOGENIC WASTES, CONVERTING ANY OUTPUT (WASTES) TO BENEFICIAL INPUTS (RESOURCES) TO THE BIOSPHERE SHOULD BE A NEW RESPONSIBILITY FOR ECOTOXICOLOGISTS. • This approach will require a major retraining effort as well as a major recruitment effort since current ecotoxicology tests require much skill and time and an inadequate number of ecotoxicologists exist for the data gathering needed at present. • Much can be done immediately by reducing anthropogenic output so ecotoxicologists will have fewer problems to solve.
PRESENT ANTHROPOGENIC WASTES (OUTPUT) MIGHT NOT CAUSE BIOSPHERIC DISEQUILIBRIUM IF THE HUMAN POPULATION WERE ONLY 1 BILLION AND PER CAPITA CONSUMPTION OF NATURAL RESOURCES DID NOT REDUCE NATURAL CAPITAL (E.G., THE OCEANS).
HUMANKIND’S PRESENT PRACTICES ARE UNSUSTAINABLE. • Ecological overshoot (i.e., using natural resources more rapidly than the biosphere can regenerate them) is already a serious problem. • Exponential human population growth means increased resource consumption. • Perpetual economic growth ensures perpetual increases in resource consumption. • Decreased biodiversity and damage to ecosystem function mean reduced ecosystem services.
ILLUSTRATIVE PRELIMINARY STEPS TO ENHANCE THE HEALTH OF THE BIOSPHERE • Cease subsidizing fossil fuel extraction since it is a major contributor to anthropogenic greenhouse gas emissions. • Subsidize alternative energy sources that are carbon free (except nuclear energy – extended, long-term storage problems for high-level radioactive wastes has not been resolved). • Ban production of automotive fuel from sources where the input/output ratio is not favorable (e.g., corn to ethanol, tar sands). • Return the oceans to their normal, slightly alkaline pH – the oceans are a major part of the biosphere and cover about 70% of Earth’s surface, and they have gone from alkaline to acidic because of carbon dioxide accumulation. • Stop using the global commons (i.e., atmosphere, land, oceans) as dumping grounds for anthropogenic wastes (e.g., plastic).
NURTURING THE HEALTH OF THE BIOSPHERE MEANS NOT PUSHING THE RESILIENCY OF THE BIOSPHERE UNTIL AN IRREVERSIBLE TIPPING POINT IS REACHED. • Since the location of tipping points is unknown until crossed, precautions and nurturing are the only rational approaches to avoiding disequilibrium. • Sustainable use of the planet is the most effective way to avoid tipping points. • Crossing a tipping point means adjusting to a new set of environment conditions.
MULTIPLE, INTERACTIVE CRISES CANNOT BE DEALT WITH INDIVIDUALLY. • The global crises are: climate change, overpopulation, ecological overshoot, environmental toxicants (e.g., endocrine disruptors), habitat loss, biotic impoverishment (i.e., loss of biodiversity), energy sources (e.g., transition to non-carbon sources). • Growth requires resources. • Passing a new tipping point in any single category will affect all others. • People are reluctant to discuss overpopulation and unwilling to change lifestyles to the degree necessary to live sustainably. • The conventional wisdom is to deal with only a single crisis at a time, but this approach is not a good strategy for coping with multiple, interactive crises.
THE VALUE SYSTEM FOR SUSTAINBLE USE OF THE PLANET IS ECO-ETHICS AND SUSTAINABILITY ETHICS, WHICH MUST CONSIST OF A SERIES OF VALUE JUDGMENTS TO WHICH HUMANITY IS COMMITTED.1-3 • Eco-ethics is about humankind’s relationship with natural systems.2,3 • Sustainability ethics involves eco-ethics but is primarily intergenerational ethics. • The core value of sustainability ethics is “use without abuse” of natural systems so that many generations of humans have a habitable planet to live on. • Humankind is not even close to living sustainably, and the threat of passing one or more global tipping points increases continually. However, for many nations, the focus must first be on survival and then a return to the quest for sustainability when the global crises have lessened.4 • Since many people will not believe in tipping points until a catastrophe has occurred, risk communication will be a major challenge.
ARE THE ECONOMY AND ECONOMIC GROWTH MORE IMPORTANT THAN THE SURVIVAL OF HOMO SAPIENS? • In the United States and elsewhere, remedial actions on the global climate crises have been postponed because of a fear that such actions might have an adverse effect upon the economy. This attitude has been commonplace despite clear evidence that low-lying islands and major estuaries are already in serious danger if “business as usual” continues. • If civilization is destroyed or Homo sapiens goes extinct, the human economy and economic growth will no longer exist. • Persuasive evidence exists that switching to non-carbon energy sources (e.g., solar, wind) will increase security and have substantial short- and long-term economic benefits. • Fossil fuels will have a diminished energy role in the future, so a major transition to alternative sources of energy should not be feared. • These changes will facilitate the opportunities for enabling ecotoxicology to move from attempting to protect the biosphere to enhancing the health of the biosphere. • If successful, these efforts will substantially reduce the ecotoxicological research needed to reduce risk and enhance security.
TO CONVERT ANTHROPOGENIC WASTES FROM HAZARDOUS OUTPUTS TO BENEFICIAL INPUTS INTO THE BIOSPHERE, THE FOLLOWING APPROACH SHOULD BE EFFECTIVE. • Cease production of products harmful to the biosphere. • Examine each production process to eliminate hazardous byproducts and replace them with byproducts that will benefit the biosphere. • If these steps cannot be achieved, determine if the hazardous byproducts can be used in any manufacturing process. • If the byproducts cannot be used in any manufacturing process, determine if they can be altered to make them industrially or biologically useful.
SUSTAINABLE USE OF THE PLANET REQUIRES THAT NO ANTHROPOGENIC WASTES BE HARMFUL TO THE BIOSPHERE (WHICH INCLUDES HUMANS). • No anthropogenic wastes or products should damage the biospheric life support system. • Nuclear power has two serious, unsustainable components: (1) vast amounts of cooling water are necessary, (2) high-level radioactive wastes require long-term storage. • No further damage to the biospheric life support system can be tolerated since such damage would substantially increase the risks of biospheric disequilibrium. • Ethics and value judgments must be important components of all opportunity/cost analyses: science can provide evidence but human society must provide values.
DUMPING HAZARDOUS ANTHROPOGENIC WASTES INTO THE BIOSPHEREIC LIFE SUPPORT SYSTEM IS UNHEALTHY.
A MAJOR EFFORT SHOULD BE MADE TO REDESIGN ANTHROPOGENIC WASTES SO THEY WILL SERVE AS INPUTS (RESOURCES) IN NATURAL SYSTEMS.
Acknowledgments: I am indebted to Darla Donald for transcribing the handwritten first draft and for editorial assistance and to Valerie Sutherland for converting it to Power Point. References 1Cairns, J., Jr. 1994. Ecological restoration: re-examining human society’s relationship with natural systems. The Abel Wolman Distinguished Lecture. Water and Science Technology Board, National Research Council, Washington, DC. 2Cairns, J., Jr. 2003. Eco-ethics and Sustainability Ethics, Book 1. Ethics in Science and Environmental Politics, Eco- ethics International Union, Oldendorf/Luhe, Germany. 3Cairns, J., Jr. 2004. Eco-ethics and Sustainability Ethics, Book 2. Ethics in Science and Environmental Politics, Eco- ethics International Union, Oldendorf/Luhe, Germany. 4Cairns, J., Jr. 2007. Postponing the quest for sustainability: survival first – then sustainability. Chapter 25 in My Quest for Sustainable Use of the Planet, J. Cairns, Jr. www.johncairns.net.