What are the trends in wastes and their effects on human health and the environment?
Virtually every resident, organization, and human activity in the United States generates some type of waste. Many different types of waste are generated, including municipal solid waste, agricultural and animal waste, medical waste, radioactive waste, hazardous waste, industrial non-hazardous waste, construction and demolition debris, extraction and mining waste, oil and gas production waste, fossil fuel combustion waste, and sewage sludge (see Glossary for detailed descriptions of these wastes).
The amount of waste produced is influenced by economic activity, consumption, and population growth. Developed societies, such as the United States, generally produce large amounts of municipal solid waste (e.g., food wastes, packaged goods, disposable goods, used electronics) and commercial and industrial wastes (e.g., demolition debris, incineration residues, refinery sludges). Among industrialized nations, the United States generates the largest amount of municipal solid waste per person on a daily basis.1
Waste generation, in most cases, represents inefficient use of materials. Tracking trends in the quantity, composition, and effects of these materials provides insight into the efficiency with which the nation uses (and reuses) materials and resources and provides a means to better understand the effects of wastes on human health and ecological condition.
Once generated, wastes must be managed through reuse, recycling, storage, treatment, and/or disposal. Most municipal solid wastes and hazardous wastes are managed in land disposal units. For hazardous wastes, land disposal includes landfills, surface impoundments, land treatment, land farming, and underground injection.
Modern landfill facilities are engineered with containment systems and monitoring programs. Waste management practices prior to Resource Conservation and Recovery Act (RCRA) regulations left legacies of contaminated lands (see Contaminated Land).
Current approaches to waste management evolved primarily due to health concerns and the need to control odors. In the past, waste often was deposited on land just outside developed areas.
More recently, excavation of land specifically for deposition of wastes became common, often accompanied by burning of wastes to reduce volume, a practice eventually determined to be a contributor to degraded air quality in urban areas. Burning of wastes occurred at multiple levels, from backyard burning to large, open-burning dumps of municipal solid wastes to onsite burning of commercial and industrial wastes.
Land disposal created problems such as ground water contamination, methane gas formation and migration, and disease vector hazards.
The effects associated with waste vary widely and are influenced by the substances or chemicals found in waste and how they are managed. Although data do not exist to directly link trends in waste with effects on human health and the environment, the management of waste may result in waste and chemicals in waste entering the environment.
- Hazardous waste, by definition, has the potential to negatively affect human health and the environment, which is why it is so strictly regulated. Hazardous wastes are either specifically listed as hazardous by EPA or a state, or exhibit one or more of the following characteristics: ignitability, corrosivity, reactivity, or toxicity. Generation and management of hazardous wastes can contaminate land, air, and water and negatively affect human health and environmental conditions.
- Municipal solid waste landfills are the third-largest source of human-related methane emissions in the United States, accounting for approximately 18 percent of these emissions in 2012.2 Methane is one of several non-CO2 gases that contribute to global climate change. Methane gas is released as wastes decompose, and emissions are a function of the total amount and makeup of the wastes as well as management facility location, design, and practices.3
EPA is interested because gas emissions can be affected by recycling and changing product use. For example, recycling office paper or aluminum can reduce environmental effects (e.g., by reducing the need to harvest trees or mine bauxite to produce aluminum), and it will also create positive environmental benefits, such as reductions in energy consumption and greenhouse gases (e.g., emissions associated with the production of products from virgin materials).4
The ROE presents two indicators to provide information on trends in waste generation and management: Municipal Solid Waste and RCRA Hazardous Waste. Both indicators measure trends in the national generation and management of certain types of waste, as well as trends in the intensity of certain types of waste generation (i.e., the rate at which natural resources are being consumed to support the needs of the U.S. population and economy).
While numerous waste-related data collection efforts exist at the local, state, and national levels (including the Hazardous Waste Biennial Report, which reports on the nature, quantities, and disposition of hazardous waste), the availability of indicators on how materials are generated, used, and managed is constrained by the existing data on non-hazardous waste management.
- The two types of waste addressed in the indicators represent a small percentage of the total amount of waste generated in the United States—the national amounts and percentage of total waste are not known.
- Over the past 35 years, the paradigm has shifted from a “waste management” approach to “sustainable materials management” focusing on resource, environmental, and human health impacts over the entire life cycle of materials. EPA is interested in better understanding the trends in the use and management of materials.
- The amount of waste generated and managed may describe ambient conditions in terms of wastes in the environment, but does not provide any indication of the effects on human health or environmental condition.
There have been changes in the management of wastes over the past few decades, designed to reduce hazardous and potential exposures, but data that more concretely measure the overall exposure (and thus effects on human health and the environment caused by wastes and waste management practices) are still lacking.
 Organization for Economic Cooperation and Development (OECD). 2015. Municipal waste, Generation and Treatment: Municipal waste generated per capita. OECD.StatExtracts.
 U.S. Environmental Protection Agency. 2006. Solid waste management and greenhouse gases: A life-cycle assessment of emissions and sinks. Third edition. Washington, DC.