Controlling Pollution

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Because of the many environmental tragedies of the mid-20th century, many nations instituted comprehensive regulations designed to repair the past damage of uncontrolled pollution and prevent future environmental contamination.

International agreements have also played a role in reducing global pollution. The Montréal Protocol on Substances that Deplete the Ozone Layer (1987) set international target dates for reducing the manufacture and emissions of the chemicals, such as CFCs, known to deplete the ozone layer. The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and Their Disposal (1989) serves as a framework for the international regulation of hazardous waste transport and disposal.

Since 1992 representatives from more than 160 nations have met regularly to discuss methods to reduce greenhouse gas emissions. In 1997 the Kyōto Protocol was devised, calling for industrialized countries to reduce their gas emissions by 2012 to an average 5 percent below 1990 levels. At the end of 2000 the Kyōto Protocol had not yet been ratified; negotiators were still working to find consensus on the rules, methods, and penalties that should be used to enforce the treaty.

Regulations and legislation have led to considerable progress in cleaning up air and water pollution in developed countries. Vehicles in the 1990s emit fewer nitrogen oxides than those in the 1970s did; power plants now burn low-sulfur fuels; industrial stacks have scrubbers to reduce emissions; and lead has been removed from gasoline. Developing countries, however, continue to struggle with pollution control because they lack clean technologies and desperately need to improve economic strength, often at the cost of environmental quality. The problem is compounded by developing countries attracting foreign investment and industry by offering cheaper labor, cheaper raw materials, and fewer environmental restrictions.

Nongovernmental citizen groups have formed at the local, national, and international level to combat pollution problems worldwide. Many of these organizations provide information and support for people or organizations traditionally not involved in the decision-making process.

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