Environmental Pollution
Environmental Pollution
Introduction
Environmental pollution is the discharge of material, in any physical state, that is dangerous to the environment or human health. Most industrialized and developing countries, and many intergovernmental organizations, have developed maximum exposure values for pollutants. Many regulate atmospheric emissions to keep their levels compatible with environmental equilibrium and human health.
Although pollution was regarded primarily as a localized problem until the last third of the twentieth century, environmental pollution is a significant part of the contemporary international political agenda. This is especially true of atmospheric and marine pollution, since neither is contained within national borders. With regard to climate change, environmental pollution is the defining issue: limiting anthropogenic greenhouse-gas emissions is acknowledged by scientists as fundamental to mitigating the effects of global climate change.
Historical Background and Scientific Foundations
Awareness of the wider problems caused by environmental pollution is only a comparatively recent phenomenon. Until at least the middle of the twentieth century, it was regarded primarily as a localized problem. However, local action was rarely sufficient to address problems that were not confinable to one location. Centralized research and legislation on far-reaching environmental issues—such as polluted rivers or smog—were scant.
This was especially true for outdoor air pollution—a principal contributory factor to climate change. The picture started to change after a lethal episode of air pollution in Donora, Pennsylvania, in 1948, left 20 dead and hundreds seriously ill; and severe episodes of smog were observed in London in 1952. By 1957, the U.S. Public Health Service had organized an air pollution division in the Bureau of State Services and started a program of health effects research and training programs in universities. At this time, research focused on human health impacts in urban centers, but it formed a starting point for debate about alternative air pollution control strategies.
The birth of the modern environmental movement in the latter–1960s gave rise to greater awareness of environmental pollution, and also to political pressure to implement measures to counteract it. In the United States, the passage of the National Environmental Policy Act (NEPA) in 1970 transformed pollution from a localized or statewide concern into a federal one. A raft of federal laws legislating all manner of pollution—airborne (Clean Air Act 1970); water (Clean Water Act 1972); oil (Water Quality Improvement Bill 1970); and noise (Noise Control Act 1979)—was passed during the 1970s.
By the 1970s, a link between respiratory disease and particulate air pollution had been well established. Links were also established between annual respiratory mortality and exposure to air pollution from coal burning and other atmospheric emissions from heavy industry. Partly as a consequence of growing public concern about air pollution, atmospheric scientists were able to secure additional funding for new research into human impacts on the atmosphere. Within a matter of years, it became clear that sulfate aerosols, CFCs, and other anthropogenic emissions, including CO2, played a significant role in the depletion of the planet's atmospheric ozone layer.
Environmental pollution became an international concern. In the late 1980s, a series of international conferences explored the problem of climate change. The period also witnessed the founding of scientific research bodies such as the Intergovernmental Panel on Climate Change (IPCC). In 1987, some 50 countries adopted the Montreal Protocol, which specified a 50% reduction in fully halogenated CFCs by the century's end. In 1990, the Montreal Protocol was amended to include a total ban on CFCs. This was followed by the U.N. Framework Convention on Climate Change (UNFCCC) in 1992, and the Kyoto Protocol in 1997.
The IPCC and other international scientific bodies studying climate change have attempted to divorce the scientific study of environmental pollution from the social, political, and even physical contexts of its production. The IPCC's otherwise comprehensive glossary does not provide a definition for the term environmental pollution. As such, defining what constitutes environmental pollution remains the domain of national governments and specific international conferences and agreements. However, there is some consensus.
According to the U.S. National Aeronautics and Space Administration (NASA), environmental pollution is: “alterations of the natural environment that are harmful to life, normally as produced by human activities….[This includes] atmospheric, water, soil, noise, and thermal pollution.”
WORDS TO KNOW
CLEAN AIR ACT: Any law that seeks to control air pollution may be referred to as a “clean air act.” In climate literature, the U.S. Clean Air Act of 1970 is often spoken of as “the” Clean Air Act.
NATIONAL ENVIRONMENTAL POLICY ACT (NEPA): U.S. federal law signed by President Richard Nixon on January 1, 1970. The act requires federal agencies to produce Environmental Impact Statements describing the impact on the environment of projects they propose to carry out.
OZONE LAYER: The layer of ozone that begins approximately 9.3 mi (15 km) above Earth and thins to an almost negligible amount at about 31 mi (50 km) and shields Earth from harmful ultraviolet radiation from the sun. The highest natural concentration of ozone (approximately 10 parts per million by volume) occurs in the stratosphere at approximately 15.5 mi (25 km) above Earth. The stratospheric ozone concentration changes throughout the year as stratospheric circulation changes with the seasons. Natural events such as volcanoes and solar flares can produce changes in ozone concentration, but man-made changes are of the greatest concern.
PEA SOUPER: Nineteenth-century term for a thick smog episode in London. London continued to suffer extreme smog episodes through the 1950s.
According to the British government (as per its Pollution and Prevention Control Act 1999): “Environmental pollution means pollution of the air, water or land which may give rise to any harm.” The act further states that “‘harm’ means—(a) harm to the health of human beings or other living organisms; (b) harm to the quality of the environment, …(c) offence to the senses of human beings.” Environmental harm includes: “(i) harm to the quality of the environment taken as a whole, (ii) harm to the quality of the air, water or land, and (iii) other impairment of, or interference with, the ecological systems of which any living organisms form part.”
According to the EU (as per its 1996 Pollution Directive): “‘Pollution’ shall mean the direct or indirect introduction as a result of human activity, of substances, vibrations, heat or noise into the air, water or land which may be harmful to human health or the quality of the environment, result in damage to materiel property, or impair or interfere with amenities and other legitimate uses of the environment.”
In the context of climate change, the IPCC also publishes comprehensive guidelines for national greenhouse gas inventories. These provide methodologies to the UNFCCC's signatories for estimating anthropogenic emissions by sources. While resisting use of the term “pollution,” the IPCC guidelines form the internationally recognized definition of humanmade atmospheric pollutants that impact global warming. They are: Carbon dioxide (CO2); methane (CH4); nitrous oxide (N2O); hydrofluorocarbons (HFCs); perfluorocarbons (PFCs); sulfur hexafluoride (SF6); nitrogen trifluoride (NF3); trifluoromethyl sulfur pentafluoride (SF5CF3); halogenated ethers; and other halocarbons not covered by the Montreal Protocol.
Impacts and Issues
The defining of environmental pollution as a national and international problem—rather than a local one—helped shape environmental policy. Today, clear conceptions of what forms of pollution influence global warming serve as the principal agents for mitigating climate change. Efforts to cancel emissions of such pollutants may well become the defining issue of the age.
Already, efforts to counteract environmental pollution have had substantial impacts. Landmark legislation, such as U.S. and U.K. Clean Air Acts, has improved urban and rural environments and the lives of millions of its people. For example, “pea soupers,” the term once given to London's smog-ridden mornings, are long a part of the past. For the first time in centuries, salmon are once again found in the city's river Thames. Global efforts to counteract pollution have had a positive impact on human lives.
Regulation of ozone-depleting substances and greenhouse-gas emissions is helping combat atmospheric environmental pollution. The terms of the amended Montreal Protocol—which outlawed fully halogenated CFCs—has aided the decrease or leveling off of atmospheric concentrations of the most important chlorofluorocarbons and related chlorinated hydrocarbons. Recognition of other pollutants that are harmful to the atmosphere and moves to limit their emission has not yet stabilized greenhouse gas-levels, although it may have decreased the rate at which atmospheric concentrations are increasing.
See Also Atmospheric Pollution;Chlorofluorocarbons and Related Compounds; Environmental Policy.
BIBLIOGRAPHY
Books
Cherni, Judith A. Economic Growth Versus the Environment: The Politics of Wealth, Health, and Air Pollution. New York: Palgrave, 2002.
Dowey, Scott Hamilton. Don't Breath the Air: Air Pollution and U.S. Environmental Politics, 1945–1970. College Station, TX: Texas A&M University Press, 2000.
Hill, Marquita K. Understanding Environmental Pollution. Cambridge: Cambridge University Press. 2004.
Trivedy, R. K. Encyclopaedia of Environmental Pollution and Control. Karad: Enviro-media, 1995.
Periodicals
Pope III, C. Arden, et al. “Health Effects of Particulate Air Pollution: Time for Reassessment.” Environmental Health Perspectives 103 (1995): 472–80.
Whittenberger, James L. “Health Effects of Air Pollution: Some Historical Notes.” Environmental Health Perspectives 91 (1989): 129–130.
James Corbett