EPA recently lifted a 25-year ban on the sale of land contaminated with polychlorinated biphenyls or PCBs, according to USA Today. The newspaper obtained an Aug. 14 internal memo in which an agency official called the ban “an unnecessary barrier to redevelopment.” Previously, polluted properties could not be sold until PCBs were cleaned up. The policy change will make it more difficult to track the sale of contaminated sites, of which there are more than 1,000 nationwide, according to EPA officials. PCBs were once widely used in the United States as lubricants and coolants. But this stopped in the late 1970s when they were found to build up in the environment and endanger human health. The government recognizes PCBs as probable carcinogens, and studies have found them to damage the liver, kidney, stomach and thyroid gland.