Which characteristic is important for a substance to be considered hazardous waste?

For a substance to be considered hazardous waste, one important characteristic is that it must be a material that no longer serves its intended purpose. This reflects the definition of waste, which indicates that the material is discarded and is not being used for its original function anymore. In the context of waste management, once a substance has fulfilled its intended use or has been deemed waste due to degradation or obsolescence, it can qualify as hazardous if it also exhibits other properties that pose a threat to human health or the environment.

The definition encompasses various types of waste, including industrial byproducts, discarded consumer products, and leftovers from manufacturing processes. The focus on the material's status as no longer useful highlights the importance of process continuity in waste generation.

While elements such as recyclability or toxicity may play a role in determining how a waste material is handled afterwards, they do not directly impact whether a substance can be classified as hazardous waste. Similarly, the ease of disposal does not relate to its hazardous nature but rather to the logistics involved in managing the waste. Therefore, the idea that the material must no longer serve its intended purpose aligns directly with regulatory frameworks governing hazardous waste classification and management.