What is a major characteristic that defines hazardous waste?

A major characteristic that defines hazardous waste is that it often contains substances that can pose a significant risk to human health and the environment. Hazardous waste can be ignitable, corrosive, reactive, or toxic, meaning it has the potential to release harmful substances if not properly managed.

The characteristic of being infectious is relevant because hazardous waste can indeed include medical waste, such as discarded needles and contaminated materials, which can lead to the spread of infectious diseases. This type of waste requires careful handling and disposal to prevent exposure and maintain public health safety.

Other characteristics such as being non-reactive, inert, or useful do not define hazardous waste. Non-reactive and inert materials are typically less concerning in terms of environmental risk, whereas useful materials are usually not classified as waste at all. Hazardous waste is primarily characterized by its potential to harm rather than by being non-reactive, inert, or beneficial.