Plutonium Powered Pacemaker (From 1974)(orau.org) |
Plutonium Powered Pacemaker (From 1974)(orau.org) |
This Pu-238 is the same stuff that's powering the Voyager probes and a few Mars rovers.
Note that it's not Pu-239, which is fissile nuclear fuel for chain reactions (power plants, bombs, etc.)
Wouldn't you be more concerned about dose rates in tissues near the device though, rather than whole body dose? At the surface of the pacemaker it would be about 90 rem / year.
Where are these gamma rays and neutrons coming from? The decay chain for Pu-238 is via alpha emission (Pu-238 -> U-234 -> Th-230 -> ...) which won't penetrate the casing.
I'm not implying the risk was miscalculated in the medical approval process, I'm sure it's safe enough. I'm just questioning OP's statement about radiation dose, yes it's strictly true but seems to underplay the importance of the nature of the dose.
How do modern pacemakers work? Can they be recharged inductively or is surgery required to replace batteries periodically?