According to sources, an Environmental Protection Agency (EPA) draft risk assessment concludes the widely used gasoline additive MTBE (methyl tertiary-butyl ether) is a “likely” human carcinogen. If the document is approved, it could result in significant and extensive cleanups in the U.S.

MTBE liability protection has been a highly controversial issue during recent congressional energy legislation debates.

Sources are reporting that EPA is currently circulating a draft risk study within the agency which pinpoints kidney and lymph node tumors as a result of MTBE exposure. Presently, the draft findings are undergoing review by EPA's waste, water, toxics and air offices.