# K-40 causes 4300 decays/s in our bodies? **URL:** \ **Category:** Factual Questions\ **Created:** [June 6, 2019, 4:13am UTC](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110 "2019-06-06T04:13:34Z")\ **Posts on this page:** 5\ **Page:** 2
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [June 7, 2019, 7:23pm UTC](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110/21 "2019-06-07T19:23:23Z")
> [@Nava](#): > > OK, so… first you say that the original cell isn’t alive any more and then that it doesn’t die? We have different definitions of life, death and existence, I’m afraid… but that would go to a different forum 😃 Nope, I **didn’t** say that at all, I explicitly refuted it. Your implied model seems to be that the cell is factory that “makes” two cells, and that this factory is a separate entity that then dies. But that model is wrong. The cell duplicates its contents, and then _divides_, all the material present is split between two cells that are the product of that fission. There is no sense in which anything dies. It’s not just semantics, the notion that something dies in the process of cell division is wrong. We start with one living cell. It divides in two, there are now two living cells. I appreciate that you may have a desire to disagree with anything I say given our recent discussion on another topic, but this is GQ, and this is not a matter of subjective opinion or semantics. > **[Cell division](https://en.wikipedia.org/wiki/Cell_division)** > > Cell division is the process by which a parent cell divides into two daughter cells. Cell division usually occurs as part of a larger cell cycle in which the cell grows and replicates its chromosome(s) before dividing. In eukaryotes, there are two distinct types of cell division: a vegetative division (mitosis), producing daughter cells genetically identical to the parent cell, and a cell division that produces haploid gametes for sexual reproduction (meiosis), reducing the number of chromoso Pr... ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [June 7, 2019, 7:33pm UTC](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110/22 "2019-06-07T19:33:16Z")
> [@Inigo\_Montoya](#): > > How low, and how much annihilation are we talking about? Spontaneous human combustion? Hiccups? Sudden craving for anchovies? I don’t know the numbers, but a total WAG is that you may get one neutrino-antineutrino annilation in your body every million years. That number could be off by several orders of magnitude, so don’t quote me on it. As far as the energy of such an annhilation, when two particles annihilate, the masses of the two are converted to photons. The mass of a single neutrino is so low you wouldn’t even notice if a million of them did it at once. ---
**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\ **Post date:** [June 7, 2019, 11:44pm UTC](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110/23 "2019-06-07T23:44:34Z")
IIRC, the danger of cancer is greatest when the radiation occurs when the cell is dividing. Radiation can cause mutations in the DNA easier during cell division. Having the radioactive substance internal is more dangerous than just being exposed externally. This is why certain radioactive particles are more dangerous than others. One of the major concerns is strontium > [@](#): > > Strontium-90 is a “bone seeker” that exhibits biochemical behavior similar to calcium, the next lighter group 2 element.[3][7] After entering the organism, most often by ingestion with contaminated food or water, about 70–80% of the dose gets excreted.[2] Virtually all remaining strontium-90 is deposited in bones and bone marrow, with the remaining 1% remaining in blood and soft tissues.[2] Its presence in bones can cause bone cancer, cancer of nearby tissues, and leukemia. This is also why radiation is more dangerous for babies and small children because their cells are dividing faster. Looking at potassium: > [@](#): > > Potassium is the third most abundant mineral in the body (5). > > . . . > > Roughly 98% of the potassium in your body is found in your cells. Of this, 80% is found in your muscle cells, while the other 20% can be found in your bones, liver and red blood cells (6Trusted Source). So potassium is distributed throughout the body. Back to strontium. I found this source for the amount which can cause cancer > [@](#): > > A little over 10 µg of Sr-90, if inhaled in insoluble form, would give a sufficient dose to cause cancer with high probability. If my math done in my head late at night is correct, this is less than 1/1000 of the mass of K-40 referred in the OP as being safe. ---
**Author:** ![swaneycpcc](https://avatars.discourse-cdn.com/v4/letter/s/e9c0ed/32.png) [@swaneycpcc](https://boards.straightdope.com/u/swaneycpcc)\ **Post date:** [June 8, 2019, 4:32am UTC](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110/24 "2019-06-08T04:32:03Z")
I thought of starting a different thread, but since people have already gone this far I’ll ask it here. If a cell divides we call both cells “new,” right? I mean, if we didn’t, then all of our cells would be the same age–since conception. But I hear people talk about old cells self-destructing, or about other cells killing them because they’re too old (and too likely to have something go wrong, I think). How does cell division sort of “remake” the cell and make it new-ish again? Why kill an old cell when you could just have it divide? How are some cells able to stay new while others don’t? Is it just that some cells aren’t made to ever divide, or that they just didn’t and now they might be too messed up to trust them to replicate themselves? ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [June 8, 2019, 2:24pm UTC](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110/25 "2019-06-08T14:24:23Z")
> [@swaneycpcc](#): > > I thought of starting a different thread, but since people have already gone this far I’ll ask it here. > > If a cell divides we call both cells “new,” right? I mean, if we didn’t, then all of our cells would be the same age–since conception. But I hear people talk about old cells self-destructing, or about other cells killing them because they’re too old (and too likely to have something go wrong, I think). How does cell division sort of “remake” the cell and make it new-ish again? It doesn’t. > [@](#): > > Why kill an old cell when you could just have it divide? You can’t. The specialized cells, like a white blood cell, are produced by stem cells. They then operate until they die. > [@](#): > > How are some cells able to stay new while others don’t? This is a qualified guess, but aging is a consequence of activity. A white blood cell “does stuff”. The stem cell it came from just sits around and occasionally makes a new white blood cell. (As mentioned before it’s slightly more complicated than that and differs between different types of stem cells. Also we haven’t even identified all types of stem cells necessary for producing all the different types of specialized cells, or at least we hadn’t a couple of years back. > [@](#): > > Is it just that some cells aren’t made to ever divide, or that they just didn’t and now they might be too messed up to trust them to replicate themselves? I think there’s also a confusion in that there are different kinds of aging. A white blood cell wears out doing it’s job. That’s aging. The cells that keep dividing have a “countdown clock”, the telomeres and can only divide so many times before they run out of telomere. That’s a different type of aging. There are also mechanisms that can un-age DNA. I’m sure we’ve had threads on this before. [Previous page](https://boards.straightdope.com/t/k-40-causes-4300-decays-s-in-our-bodies/835110.md?page=1)