A-Bomb Babies

Robert Krulwich's segments on NPR--Krulwich on Science--always help explain the science world around us in a delightful way.

This past Sunday, Krulwich explained "How A-Bomb Testing Changed Our Trees" and changed some of us, too. The atmospheric a-bomb tests of the 1950s and '60s blew lots of neutrons in the air, some of which combined with carbon-12 to create carbon-14 atoms. The boost in carbon-14 atoms was absorbed into every tree in the world that was alive during that time, creating a spike in carbon-14 that's an indelible marker within the tree.

And that which is true for the trees is true for us, too. People ate the fruit of trees--apples, pecans, pears, oranges, etc.--and gained an internal knowledge of carbon-14 which was passed along to the children of the era (giving post-lapsarian a whole new implication). As a result, people born during the atmospheric tests have a carbon-14 spike in their DNA. As Krulwich says, we can date people with carbon-14 testing. 

You can listen to the story at NPR's webpage (4:24 min.).