PV is polycythemia vera, a rare blood cancer. "Some residents blame their illnesses on a recycler that accepted hundreds of thousands of gallons of paint sludge, waste oils, used solvents, PCBs, cyanide, pesticides and many other known or suspected carcinogens...Environmental officials shut down the site in 1979, and it was later placed on the federal Superfund list and cleaned up...The U.S. Agency for Toxic Substances and Disease Registry said Monday that it confirmed an elevated number of cases of polycythemia vera, or PV, in a 20-mile stretch between Hazleton and Tamaqua. It remains the first and only cluster of PV ever recorded in the United States.."