Linguistic detoxification is a political term used by some environmentalists to describe when, through legislation or other government action, the definitions of toxicity for certain substances are changed, or the name of the substance is changed, so that fewer things fall under a particular classification as toxic. An example is the classification of some low-level radioactive waste as "beyond regulatory concern", which permits it to be buried in conventional landfills. Another example is the EPA renaming sewage sludge to biosolids, and allowing it to be used as fertilizer, despite the fact that it often contains many hazardous materials including PCBs, dioxin, arsenic, cadmium, lead, and asbestos. The origin of this phrase has been attributed to environmental activist and author Barry Commoner.