Koch Industries is the number producer of toxic waste in the US, and that does not include their many TV commercials for right-wing causes.
From Dark Money, The Hidden History of the Billionaires Behind the Rise of the Radical Right by Jane Mayer.
“The numbers regarding Koch Industries’ pollution were incontrovertible. In 2012, according to EPA’s Toxic Release Inventory database, which documents the toxic and carcinogenic output of eight thousand American companies, Koch Industries was the number one producer of toxic waste in the United States. It generated 950 million pounds of hazardous materials that Year. Of this total output, it released 56.8 million pounds into the air, water, and soil, making it the country’s fifth-largest polluter. The company was also among the largest emitters of greenhouse gases in America, spewing over twenty-four million tons of carbon dioxide a year into the atmosphere by 2011, according to the EPA, as much as typically emitted by five million cars.”