Hazardous waste is any waste material that can pose a threat to human health or the environment due to its toxic, corrosive, flammable, or reactive properties. Common examples include chemicals, pesticides, batteries, medical waste, paints, and certain electronics. Because of the potential danger, hazardous waste requires specialized handling, storage, and disposal methods to prevent soil, water, and air contamination.

Regulations often govern the management of hazardous waste, ensuring it is collected, transported, and treated safely to protect public health and minimize environmental harm. Proper hazardous waste disposal often involves treatment facilities that neutralize or securely contain hazardous substances, reducing their impact on ecosystems.