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Municipal solid waste—more commonly known as trash or garbage—consists of everyday items we use and then throw away. These items may include: 

  • Bottles
  • Food scraps
  • Old appliances, clothes, and furniture
  • Paper products 
  • Product packaging

Other types of waste include biological, chemical, industrial, and medical waste. Properly disposing of all waste helps prevent hazards to human health and the environment.

See also: Benzene Persistent Organic Pollutants (POPs) Polybrominated Diphenyl Ethers (PBDEs) Carbon Dioxide Dioxins Methane Endocrine Disruptors

What are they?

Illegal dumping is the disposal of waste without a permit. Illegally dumped materials may include: 

Scrap tires and bulky items may be illegally dumped because they are banned from landfills and their proper disposal may be expensive. 

Why are they a concern?

Illegal dumps can contain toxic chemicals or hazardous materials and pose many human health risks. Rodents, insects, and other pests are attracted to dump sites. Disease-carrying mosquitoes can breed in the rain water that collects inside discarded tires. Polluted water runoff  from dump sites can contaminate wells and other sources of drinking water. 


If they catch on fire, tires can burn for months; tire fires are extremely difficult to extinguish. Tire fires pollute the air, soil, and water with gases, heavy metals, and oil.

What pollutants are of greatest concern and who is at risk?

Smoke from tire fires is of particular concern. It produces several pollutants, including: 

Anyone near or at an illegal dump is at risk for harm.

Additional Resources

What are they?

Incinerators burn waste material at high temperatures until it is reduced to ash. Incineration is widely used to reduce the volume and hazardous properties of: 

  • Chemical and biological waste
  • Medical waste
  • Municipal solid waste

Why are they a concern?

Incinerators may release gases and ash that harm human health. Studies have shown higher risk for some cancers, respiratory effects, and adverse birth outcomes in populations living near or working at incinerator plants. However, most of these studies looked at older facilities with high emissions. 

Newer incinerators are designed and operated to release low amounts of pollution under normal operating conditions. Off-normal (upset) conditions might result in short-term emissions greater than usual.

What pollutants are of greatest concern and who is at risk?

Pollutants emitted by incinerators that could cause the most significant health effects are:

Workers at incinerator facilities are at highest risk of exposure. The local population may be at risk by breathing air pollution. The larger regional population may be a risk if they consume food contaminated by persistent or accumulative pollutants.

What are they?

A legal, sanitary landfill is a land disposal site for non-hazardous household solid waste. At these sites, waste is spread in compacted layers. Landfills are primarily regulated by state, tribal, and local governments. They are located, designed, operated, and monitored to meet federal standards. 

Why are they a concern?

Human exposure to landfill gas can cause respiratory problems, central nervous system damage, and cancer. Landfill gas can also travel under the soil surface, build up in enclosed structures, and catch on fire. 

What pollutants are of greatest concern and who is at risk?

Two major pollutants in landfills are: 

  • Landfill gas, which is primarily made of methane
  • Leachate, which is the liquid from natural moisture that runs through the waste

Landfill gas can also include: 

People who live or work near landfills may be at risk for harm.

National Library of Medicine Resources and Databases
Additional Resources

What is it?

Different from an industrial incinerator, burning trash refers to the disposal of waste by fire in: 

  • Barrels
  • Fireplaces
  • Open pits
  • Outdoor furnaces
  • Woodstoves

Why is it a concern?

Burning trash produces many toxic chemicals that are harmful to human health. It emits much more pollution than if the same amount of trash was burned in an industrial incinerator. Trash burning, including burning of autumn leaves, is banned or heavily regulated in many parts of the United States.

What pollutants are of greatest concern and who is at risk?

Burning household trash is one of the largest known sources of dioxins in the country. Other harmful pollutants emitted by burning trash include: 

The ash from burning trash can be hazardous to human health. It can contain pollutants such as: 

These pollutants can seep from the ash into surface water, groundwater, and food grown in ash-contaminated soil. 

What are they?

At transfer stations, solid waste is unloaded from smaller trucks and reloaded into larger vehicles for transport to a final disposal site. 

Why are they a concern?

Transfer stations reduce overall traffic by consolidating smaller loads into larger vehicles. However, the station will generate additional amounts of traffic in its immediate area. This traffic can contribute to increased road congestion, air pollution, noise, and wear on roads.
Poorly sited, designed, or operated waste transfer stations can cause other problems, including:

  • Odor from garbage, particularly food waste and grass
  • Rodents and birds 
  • Stray pieces of waste that become litter

Modern transfer stations are designed to collect wastewater, control spills, and minimize blowing litter, odor, and dust.

What pollutants are of greatest concern and who is at risk?

Pollution at waste transfer stations can come from:

  • Driving over unpaved surfaces
  • Exhaust from trucks, loaders, and other equipment
  • Unloading dry, dusty waste

Air pollution at transfer stations may pose harm to local residents.

Reduce your risk

  • Do you live near a landfill?
  • Do you live near an industrial incinerator?
  • Do you burn trash?
  • Do you use well water?
  • Do not burn trash in barrels, open pits, outdoor furnaces, woodstoves, or fireplaces.
  • Avoid disposable items when possible. Buy products in bulk instead of individually wrapped or single serving sizes.
  • Reuse items when possible. Donate items you no longer need rather than throwing them away.
  • Recycle. Separate recyclable items from your trash for pickup or drop-off at local recycling centers.
  • Compost kitchen and yard waste.
  • Safely dispose of all garbage. Put garbage out for collection or bring it to your local landfill.
  • Routinely test your well water. 
  • If your well water has high levels of pollutants, contact your local or state health agency or the Centers for Disease Control and Prevention for information on how to reduce your exposure.
  • Do not let children play near dumps, incinerators, landfills, or waste transfer stations.
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