Brownfield is land that is abandoned or underutilized due to pollution from industrial use. The specific definition of brownfield land varies and is decided by policy makers and/or land developers within different countries. The main difference in definitions of whether a piece of land is considered a brownfield or not depends on the presence or absence of pollution. Overall, brownfield land is a site previously developed for industrial or commercial purposes and thus requires further development before reuse.
Example of brownfield land at a disused gasworks site after excavation, with soil contamination from removed underground storage tanks
An abandoned factory, an example of what may be considered brownfield land
Brownfield relic serves as monument in a new park in Atlantic Station area of Atlanta, Georgia, U.S.
Residential development at former brownfield site in New Jersey
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance or energy. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.
Litter on the coast of Guyana
Smog in the center of Moscow, Russia in August 2010
An industrial area, with a power plant, south of Yangzhou's downtown, China
A litter trap catches floating waste in the Yarra River, east-central Victoria, Australia.