- Although toxic waste is a worldwide problem, the United States' EPA has a well-defined method of identifying toxic waste. According to the EPA, waste is considered hazardous if it is corrosive, flammable, reactive and/or toxic. There are four main categories of toxic waste, which help to identify the causes of hazardous byproducts.
- Listed wastes are the wastes that have been specifically determined by the EPA to be hazardous. They are broken down into various lists because different regulations apply to each type. This includes the F-list, which is hazardous waste from common manufacturing processes, such as the solvents used to clean industrial complexes. The K-list includes wastes from specific manufacturing companies, such as petroleum or pesticide producers. Some commercial products become toxic if they are discarded without ever being used. This type of toxic waste includes pesticides or pharmaceuticals and is usually classified under the P-list or U-list.
- A characteristic waste is one that has not been specifically identified as a listed waste, yet still exhibits one or more qualities of toxic waste. Ignitable wastes, such as certain oils, may become hazardous if placed under extreme heat. Corrosive waste, such as battery acid, is any kind of byproduct that is capable of decaying a metal container. Reactive waste is a byproduct that is considered unstable, causing harmful fumes or even explosions. Any type of waste that is harmful if ingested or touched is generally considered toxic.
- Universal wastes are dangerous byproducts that are widely produced. This includes batteries, pesticides, light bulbs and equipment containing mercury. The EPA has applied federal regulations to each of these universal wastes in order to control the way in which the byproducts are discarded. They are not supposed to be placed in municipal landfills.
- Mixed wastes are byproducts that exhibit both radioactive and hazardous waste characteristics. High-level mixed wastes include harmful byproducts of nuclear weapon development and research, as well as nuclear power plants. Manufacturing plants, hospitals, pharmaceutical companies and pesticide producers can also produce mixed wastes.
