Given this shortage, why are some Canadian ethicists, physicians, and legislators opposed to paying for plasma from sellers? Many of them argue that the folks who sell plasma are more likely to be poor and to harbor diseases that could taint plasma supplies. Earlier this month a group of ethicists and economists organized by the Georgetown philosopher Peter Jaworski countered these arguments in an open letter that concluded these concerns are unwarranted.

The Jaworski letter begins by pointing out that “Canada is almost entirely dependent on the United States for its supply of plasma-derived medicinal products, like immune globulin, albumin, and clotting factor.” (More than 90 percent of the world’s plasma comes from the U.S.)