Wastes
What are the trends in wastes and their effects on human health and the environment?
Waste Generation
Virtually every resident, organization, and human activity in the U.S. generates some type of waste. Many different types of waste are generated, including municipal solid waste, hazardous waste, industrial non-hazardous waste, agricultural and animal waste, medical waste, radioactive 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 U.S., 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 U.S. is one of the largest generators 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.
Waste Management
Once generated, wastes must be managed through reuse, recycling, storage, treatment, energy recovery, and/or disposal or other releases to the environment. Most municipal solid wastes and hazardous wastes are managed in land disposal units. For hazardous and industrial 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. Land disposal created problems such as ground water contamination, methane gas formation and migration, and disease vector hazards.
Effects
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.
- Chemical wastes, as reported to EPA’s Toxics Release Inventory (TRI), may or may not also be considered RCRA hazardous waste, but they are toxic chemicals. TRI reporting is based on how chemicals are used and not on the characteristics of the wastes generated. While the quantity of TRI chemicals released to the air, water, or land does not indicate their health risks, the information can be used as a starting point to evaluate the potential for human exposure to TRI chemicals and whether their releases may pose risks to human health and the environment.
- Municipal solid waste landfills are the third-largest source of human-related methane emissions in the U.S., accounting for 15.5 percent of these emissions in 2021.2 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, increased recycling of municipal solid waste reduces the amount of waste sent to landfills while also conserving natural resources (e.g., timber, water, and minerals) and preventing pollution by reducing the need to collect new raw materials.4
ROE Indicators
The ROE presents three indicators to provide information on trends in waste generation and management: RCRA Hazardous Waste, Toxic Chemicals in Wastes, and Municipal Solid Waste. These indicators measure trends in the national generation and management of certain types of waste. The Hazardous Waste and Municipal Solid Waste indicators also show 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 and the Toxics Release Inventory), the availability of indicators on how materials are generated, used, and managed is constrained by the existing data on non-hazardous waste management.
- The types of waste addressed in the indicators represent a portion of the total amount of waste generated in the U.S.—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 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.
References
[1] Organization for Economic Cooperation and Development (OECD). 2022. Municipal waste, generation, and treatment: Municipal waste generated per capita. OECD.StatExtracts.
[2] U.S. Environmental Protection Agency. 2023. Inventory of U.S. greenhouse gas emissions and sinks: 1990-2021. EPA 430-R-23-002.
[3] More information on air emissions related to waste management practices, including emissions of nitrogen oxides, carbon monoxide, and air toxics, is included in Air.
[4] U.S. Environmental Protection Agency. 2020. Recycling economic information (REI) report.