Which one of the following may qualify as a hazardous waste?

Used oils can qualify as hazardous waste due to their potential toxic components and contamination with various hazardous substances. These oils often contain heavy metals, solvents, or other harmful constituents that can pose significant risks to human health and the environment if not managed properly. The characterization of used oils as hazardous waste is largely influenced by regulations such as those set forth by the EPA, which provide criteria for determining whether a substance is hazardous based on its composition and the risks it presents.

On the other hand, household waste typically includes a mix of non-hazardous items, although certain household products can be hazardous; overall, household waste does not inherently qualify as hazardous waste. Industrial wastewater may contain hazardous components, but it is not classified as hazardous waste unless it meets specific criteria. Non-toxic materials do not meet the criteria for hazardous waste because, by definition, they do not pose health or environmental risks.