4 ms·
For context, the 0.1 rem yearly dose to the patient is about 1/6th of the average background dose we all get every year. This Pu-238 is the same stuff that's p
by acidburnNSA 1y ago
For context, the 0.1 rem yearly dose to the patient is about 1/6th of the average background dose we all get every year.
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.)
- stinkbeetle 1y ago> For context, the 0.1 rem yearly dose to the patient is about 1/6th of the average background dose we all get every year. 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.
- kondro 1y agoREM is already an adjusted measure for absorption, not an general quantity of radiation.
- stinkbeetle 1y agoThis doesn't address my question. OP was talking about the whole-body dose, I'm asking about the surface and nearby dose.
- SoftTalker 1y agoPu-238 decays mainly by alpha decay which would be easily contained by the titanium casing.
- stinkbeetle 1y agoThanks. Presumably we're talking about "Dose rates at the surface of the pacemaker are approximately 5 to 15 mrem per hour from the emitted gamma rays and neutrons" though.
- SoftTalker 1y agoYeah ideally I would not want that in or close to my body but if the choice is literally life or death I guess I'll take it. How do modern pacemakers work? Can they be recharged inductively or is surgery required to replace batteries periodically?
- cyberax 1y agoIt also spontaneously fissions, with daughter products often being gamma/beta active. And it always contains some contaminants
- BurningFrog 1y agoSince it's a device that saves the life of the patient, you can accept a lot of patient risk as a tradeoff.
- stinkbeetle 1y agoObviously. That doesn't address my question though, the dose of concern is surely the nearby tissue rather than one calculated over the whole body. If the pacemaker is resting against my lungs, I'm not going to be concerned about foot cancer. 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.
- jmb99 1y agoIf I die without a pacemaker, or maybe have an increased risk of certain cancers with a pacemaker but get to live, I’d choose the pacemaker.
- stinkbeetle 1y agoDuly noted.
- LeoPanthera 1y ago[flagged]
- stinkbeetle 1y agoI definitely read that part of the article, how else do you think I came up with that 90 rem / year number?? That does does not "cover" my question though. Perhaps you didn't actually read or comprehend my question? I was wondering whether the radiation dose rates for tissue near the device is more concerning than the whole body dose. This might seem fairly obvious, but I'm no medical expert (and either way it's still not covered by the article). And it is intended to be read in the context in which it was asked. Glad I could help clear that up for you, you're welcome.
- ChuckMcM 1y agoYeah but their spouse :-) 75x larger dose.
- acidburnNSA 1y agoNo it's less! They switched from rem to millirem for the spouse.
- ChuckMcM 1y agoDang! Me and my misreading of the units. That makes more sense too.
- _kb 1y agoOr approximately 100 bananas, for scale.
- acidburnNSA 1y agoBanana equivalent dose is 0.01 mrem, so 0.1 rem = 100 mrem = 10,000 bananas.