Plastics are a subspecies of a class of materials known as polymers. These are composed of large molecules, formed by joining many, often thousands, of smaller molecules (monomers) together.

Point Source

Point source pollution is contamination that enters the environment through any discernible, confined, and discrete conveyance, such as a smokestack, pipe, ditch, tunnel, or conduit. Point source pollution remains a major cause of pollution to both air and water.


Beginning in 1970, the "environmental decade," a swift and sweeping transformation in American law radically reshaped U.S. pollution control policies.

Pollution Prevention

One key to achieving a sustainable society and tackling the complex environmental challenges of the twenty-first century is pollution prevention (P2), reducing or eliminating pollution before it is created. The idea has been discussed since 1976, but has only lately gained widespread support from both the private and public sectors.

Pollution Shifting

Pollution shifting is defined as the transfer of pollution from one medium (air, water, or soil) to another. Early legal efforts to control pollution focused on single media.

Popular Culture

Popular culture can be thought of as a composite of all the values, ideas, symbols, material goods, processes, and understandings that arise from mass media, such as the advertising and entertainment industries, as well as from other avenues, such as games, food, music, shopping, and other daily activities and processes.


Throughout most of human history, the world's population has grown gradually. It took thousands of years for the global population to reach one billion people (around 1800).


Continuing industrialization and technological advances benefit many (though not all) of the people in the developed countries, but the gap between the rich and poor countries is significant and increasing. In general, poverty deprives people of adequate education, health care, and of life's most basic necessities—safe living conditions (including clean air and clean drinking water) and an adequate food supply.

Precautionary Principle

The precautionary principle, also referred to as the precautionary approach, justifies the use of cost-effective measures to prevent environmental degradation even in the absence of full scientific certainty. This principle has obvious applications to various forms of environmental pollution.

President's Council on Environmental Quality

The Council on Environmental Quality (CEQ) was created by the National Environmental Policy Act (NEPA) in 1969 during the first term of President Richard Nixon. The primary role of the council is to advise the President on environmental policy.

Progressive Movement

The Progressive Era, a term used to describe the period between approximately 1890 and 1920, witnessed an explosion of reform efforts in America. A great number of people, for a variety of reasons, participated in a vast number of diverse reforms, including women's suffrage, political reform, and prohibition.

Property Rights Movement

The property rights movement has had a significant impact on the nation's environmental policies since 1980. The groups identified with the movement commonly oppose federal regulation or intrusion on land that is privately held, especially in cases where federal involvement is in the form of environmental laws that limit the owner's full or partial use of the land.

Public Interest Research Groups (PIRGs)

Early in his career as a consumer advocate, Ralph Nader struck on an idea for a new type of organization. "How about a law office that worked for the public's interest—not that of corporations or just individuals?" he thought.

Public Participation

Public participation is the general term for diverse formal processes by which public concerns, needs, and values are incorporated in governmental decisions. Public participation involves the use of techniques such as public meetings and hearings, advisory committees, interactive workshops, interviews, questionnaires, focus groups, and other methods to identify public concerns and preferences and address them during decision making.

Public Policy Decision Making

Public policy decision making refers to actions taken within governmental settings to formulate, adopt, implement, evaluate, or change environmental policies. These decisions may occur at any level of government.

Radioactive Fallout

The term radioactive fallout, or just fallout, refers to the debris and radioactive materials that settle out of the air after the detonation of a nuclear weapon or after a nuclear accident that produces a cloud of airborne material, or plume. Detonation of a nuclear weapon results in the immediate propagation of a shock wave and intense heat.

Radioactive Waste

Radioactive waste (or nuclear waste) is a material deemed no longer useful that has been contaminated by or contains radionuclides. Radionuclides are unstable atoms of an element that decay, or disintegrate spontaneously, emitting energy in the form of radiation.


Radon is an odorless, colorless, radioactive, though chemically unreactive gas. It has an atomic number of eighty-six, which corresponds to the number of protons found in the nucleus of any isotope of radon.

Regulatory Negotiation

Regulatory negotiation (also called negotiated rule making, policy dialogue, shared decision making, or "reg-neg") is a consensus-building process in which representatives of affected parties and sectors of the public (termed "stakeholders") work together with government officials to develop policies or regulations. Issues subjected to regulatory negotiation include car-emission levels, risk from lead exposure, and contamination cleanup levels.

Renewable Energy

Renewable energy is energy that is regenerative or, for all practical purposes, virtually inexhaustible. It includes solar energy, wind energy, hydropower, biomass (derived from plants), geothermal energy (heat from the earth), and ocean energy.

Resource Conservation and Recovery Act

The Resource Conservation and Recovery Act (RCRA) of 1976 is a federal law aimed at protecting human health and the environment by safely managing and reducing hazardous and solid nonhazardous waste. It gives the U.S.