A water system serving 6,000 Montana residents has been contaminated after an oil spill at an upstream Yellow Stone River pipeline.  Benzene is a major component in oil and is a known carcinogen.  Benzene attacks the bone marrow, where new blood cells are produced.  This substance occurs naturally in crude oil but is increased during the refining process to boost octane levels.  Click here to read the full article in The Idaho Statesman!