What term is used to describe defunct, derelict, or abandoned commercial or industrial sites that may have toxic wastes?

The term used to describe defunct, derelict, or abandoned commercial or industrial sites that may contain toxic wastes is "Brownfields." Brownfields are properties that are often complicated in their redevelopment due to the presence or potential presence of hazardous substances. These sites typically have been found to be environmentally depleted or polluted, yet they can be revitalized and reused through proper assessment and remediation processes.

The significance of brownfields lies in their potential for redevelopment, which can lead to urban renewal and economic development while also addressing environmental concerns. Programs aimed at brownfield redevelopment often involve environmental assessments, cleanup efforts, and strategies to mitigate contamination to promote safe and sustainable development.

In contrast, greenfields refer to undeveloped land that has not been previously built upon, while hazardous sites may not specifically indicate the abandoned nature of the property, and cleanup areas generally pertain to specific regions currently undergoing remediation rather than being designated as abandoned properties. Therefore, the correct term for these abandoned sites with potential toxins is brownfields.