As the cultured host of PBS’ long-running “Masterpiece Theater,” Alistair Cooke was an emblem of American taste and refinement. Since his death in 2004, Cooke has also become emblematic of a macabre and little-known market: America’s distinctly shady traffic in human remains. Unbeknownst to his family, Cooke’s bones were cut out before he was cremated and sold for ,000 to two companies that prepare human tissue for transplant. Cooke’s fate was ghoulish in the extreme — but what is even more disturbing is that it was not at all unusual. Body parts are big business in the United States. Tissue, organs, tendons, bones, joints, limbs, hands, feet, torsos and heads culled from the dead are the cornerstones of the lucrative and important business of advancing scientific knowledge and improving medical technique. Body parts are a billion-dollar industry; they underwrite both cutting-edge research and everyday medical procedures.…