[HN Gopher] Children of Chernobyl cleanup crew don't have excess...
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       Children of Chernobyl cleanup crew don't have excess mutations
        
       Author : rbanffy
       Score  : 150 points
       Date   : 2021-04-26 11:19 UTC (11 hours ago)
        
 (HTM) web link (arstechnica.com)
 (TXT) w3m dump (arstechnica.com)
        
       | MichaelMoser123 wrote:
       | maybe vodka does have some hidden effect against radiation; i
       | mean in places like Hiroshima you are said to have had a huge
       | number of birth defects, because of the bomb.
        
         | betterunix2 wrote:
         | https://www.sciencedaily.com/releases/2016/08/160811120353.h...
         | 
         | In fact, the mutation rate among the children of Hiroshima
         | survivors is greatly exaggerated and not supported by evidence.
         | According to that article _no_ health effects could be measured
         | in the next generation. Another article:
         | 
         | https://k1project.columbia.edu/news/hiroshima-and-nagasaki
         | 
         | Note the distinction mentioned here: children conceived prior
         | to the bombing, whose mothers were pregnant when they were
         | exposed to radiation, did suffer negative health outcomes.
         | Children conceived afterwards have no measurable health impacts
         | from their parents' exposure to the radiation. So the evidence
         | of these various studies seems to indicate that whatever harm
         | radiation exposure causes will not be passed on to the next
         | generation via sperm or egg cells, and we can speculate about
         | the reasons why (error correcting mechanisms, spontaneous
         | abortion in early embryonic development, etc.).
        
         | ols wrote:
         | There is no evidence supporting your claim about Hiroshima
         | https://www.ncbi.nlm.nih.gov/books/NBK234251/
        
       | patall wrote:
       | Interestingly, this is slightly contradictory to the finding that
       | children of former radar workers have more DNMs[0]. Maybe
       | explained by different type of radiation.
       | 
       | [0] https://www.eurekalert.org/pub_releases/2018-10/uob-
       | tmi10051...
        
       | bhouston wrote:
       | The human body is incredibly good at detecting unviable mutations
       | during pregnancy and it results in a miscarriage or other
       | failures early on. This would be a much better indicator to look
       | at than whether the children who survived pregnancy had excess
       | mutations.
        
         | CryptoPunk wrote:
         | While that is also a very important indicator, what proportion
         | of viable pregnancies produce children with mutations I would
         | argue is an even more important metric to study.
        
           | whoomp12342 wrote:
           | it is an important metric if it has substance, but according
           | to the above it has very little variance. Knowing how many
           | pregnancies failed versus how many failed prior to the event
           | could give us a better indicator of the damage caused.
        
             | sitkack wrote:
             | I think the question I feel the hive mind wants to answer
             | is, "How much radiation can the species live with and not
             | go extinct". If the birth rates are lower and mortality
             | right is higher we can 'make up' for that. But if the
             | offspring accrue hereditary damage, any amount is too much.
             | 
             | We will have many many tough decisions to make due to the
             | climate crisis.
        
               | Symmetry wrote:
               | And it's not just a matter of how much radiation either.
               | Zap a bunch of fruit flies with a dose of x-rays all at
               | once and see the next generation come out horribly
               | mutated. Give them that same dose of radiation over the
               | course of a month and see a perfectly healthy next
               | generation.
        
               | ipaddr wrote:
               | Has that happened flies or animals that are immune to
               | high radiation?
               | 
               | I could see the next generation having horrible
               | mutations, I could see the genes correcting some of this
               | in the 3rd generation. I could see some of mutations
               | living on but resistance to radiation would be so
               | extremely useful we would build materials out of them
               | which we are not doing today.
        
             | betterunix2 wrote:
             | That was my first thought when I saw the title. IIRC
             | roughly 1/3 of pregnancies end within weeks, often before a
             | woman is aware that she is pregnant, almost always because
             | of a genetic mutation. Given that, if the miscarriage rate
             | is higher, that would indicate that there is indeed an
             | impact, but that our genome is very good at preventing
             | dangerous mutations from propagating.
             | 
             | Another possibility is that error-correcting mechanisms are
             | good enough to deal with whatever impact exposure to that
             | level of radiation had. One hypothesis about meiosis and
             | genetic recombination is that it serves as an error
             | correcting process, where damaged genes on one chromosome
             | can be repaired using corresponding genes from the other
             | chromosome.
        
         | Symmetry wrote:
         | That's very true but even if these forces catch 99% of
         | significant mutations then you'd still see an increase in
         | pregnancies resulting from that remaining significant mutations
         | over baseline.
         | 
         | But more importantly, our genomes have a lot of "junk DNA"
         | where a mutation will not affect anything at all and almost
         | everyone has these. From the article it looks like these were
         | the mutations the researchers were looking at.
        
           | sesuximo wrote:
           | Wouldn't that depend on the size of the study? Seems like
           | catching an orders of magnitude smaller difference would
           | require orders of magnitude more samples... and the
           | population is only so big..
        
           | BitwiseFool wrote:
           | I remember hearing a hypothesis that "junk DNA" acts as a
           | kind of shielding against mutations. From a probability
           | standpoint, the more non-coding DNA you have, the less likely
           | an error is to hurt the lifeform. Taken to an extreme, if
           | every DNA sequence did something a singe error would cripple
           | the organism.
        
             | jacquesm wrote:
             | I reject the term 'junk dna'. Until we understood the
             | basics of DNA all of it was 'junk', then bit by bit we are
             | making headway into understanding some of it. If we're ever
             | done I predict there will be no junk DNA left. Nature is
             | much too efficient to spend that much energy on something
             | that it ends up not using.
        
             | syrgian wrote:
             | However, the probability of the DNA getting hit would
             | increase linearly with the amount of junk DNA, wouldn't it?
             | So the chance of good DNA getting hit is exactly the same
             | as without junk.
             | 
             | Not sure how it would help shielding the good DNA, unless
             | it acted as a barrier.
        
               | selectodude wrote:
               | Mutations from radiation come from particles literally
               | slamming into the DNA and screwing it up. The more spaced
               | out the important parts are, the lower the probability
               | that the particle hits a piece of DNA that's important.
        
               | HPsquared wrote:
               | If I place 4 cups of water out in the rain, does their
               | spacing affect how much water lands in each cup?
        
               | afiori wrote:
               | It depends on how you place them, horizontaly on a table
               | no, in a pyramid yes.
        
               | BitwiseFool wrote:
               | I see what you're getting at, but in this example there
               | would be millions of cups and the individual raindrops
               | would be spread out over a massive area of land.
        
               | jakear wrote:
               | That doesn't change anything. The probability an
               | important cup gets hit is always equal to the surface
               | integral of the rain's flux across the important cup
               | openings. Whether there are unimportant cups nearby
               | doesn't change anything.
        
             | ruined wrote:
             | that makes intuitive sense but at least in the case of
             | ionizing radiation it's a little like making a target
             | circle bigger to protect the bullseye which remains the
             | same size. there's still the same chance of hitting the
             | bullseye, no matter how you change the chance of not
             | missing the paper.
        
               | jxy wrote:
               | Think of it as a 3D sphere instead. You would get a
               | shielding effect.
        
               | cma wrote:
               | There is already one milligram of atmosphere over the
               | cross sectional area of a cell nucleus, so it doesn't
               | seem like it could change much for cosmic rays. All DNA
               | in a human cell is about 6 picograms.
               | 
               | That's 166 million times more mass of atmosphere. The
               | elements may be less effective etc. but it still seems
               | like any junk dna shielding would be negligible.
               | 
               | Maybe cosmic rays aren't the main source of ionizing
               | radiation throughout the evolutionary period though.
        
         | giantg2 wrote:
         | Aren't some of these early miscarriages not even known by the
         | woman? Wouldn't that make it difficult to measure?
        
         | lampe3 wrote:
         | I was born in August 1986. In northern Poland.
         | 
         | I was born in the 26 pregnancy week. 40 is the avg.
         | 
         | Even if it was not near Chernobyl there were more miscarriage
         | then usual.
         | 
         | So yes looking at the children that survived is not the correct
         | way looking at it.
         | 
         | I also know that getting legit data for that is nearly
         | impossible.
        
       | Pyramus wrote:
       | In most regions of southern Germany, many varieties of mushrooms
       | as well as game (in particular wild boar) are still contaminated
       | with >1k Bq/kg caesium 137 [1]. Even after 35 years (more than a
       | half life) and Chernobyl being some 1500 km away. It's just mind
       | boggling.
       | 
       | [1]
       | https://doris.bfs.de/jspui/handle/urn:nbn:de:0221-2020093023...
        
         | JoeAltmaier wrote:
         | The wild boars eat moss growing on trees, which is a tremendous
         | filter for particles.
         | 
         | A reasonable cleanup process might be, harvest tree moss and
         | reduce it to radioactive elements. Or just harvest the boars I
         | guess?
        
           | [deleted]
        
         | dgellow wrote:
         | To give a bit of context and relativize:
         | 
         | > Between September 2012 and August 2013, 297 out of 752 boars
         | exceeded legal limits of radiation -- particularly the
         | hazardous isotope Caesium 137, which has a 30-year half-life
         | and decays slowly. But to give an idea of how strict the
         | regulations really are, experts say that a person would have to
         | eat 13 kilograms of contaminated meat to get the same low-level
         | radioactive effects of being on a transatlantic flight.
         | 
         | Quote from this article from 2014:
         | https://www.nbcnews.com/news/world/chernobyl-disaster-
         | leaves....
        
           | CoastalCoder wrote:
           | > Caesium 137, which has a 30-year half-life and decays
           | slowly
           | 
           | Forgive my layman's ignorance, but "decays slowly" is just a
           | less precise version of the "30-year half-life" statement,
           | right?
        
             | bluGill wrote:
             | Either way it is wrong. 35 years is fast enough to not
             | worry about long term. It only takes a couple centuries for
             | anything with a half-life that small to complete decay. For
             | nuclear waste we worry about things with half-lives in the
             | thousands of years as we can't be sure we can store it for
             | as long as it is dangerous.
             | 
             | The real question then becomes what does it decay into? A
             | lot of things decay some something with a dangerously long
             | half life.
        
               | Pyramus wrote:
               | I'm not sure I understand, are you saying we should not
               | worry about immediate effects that only affect 1 or 2
               | generations?
               | 
               | I don't see why thinking about negative effects over
               | different timespans should be exclusive - climate change
               | certainly won't be an issue in thousands of years (if we
               | still exist).
        
               | bluGill wrote:
               | I'm saying 30 year half lifes are still considered short.
               | We still need to worry for a few generations, but that is
               | enough to remain in memory. If we forget about the
               | problem in 300 years - that is 10 half lives and so it
               | isn't a big deal. If something has a 1000 year half life
               | it will be dangerous far longer than we can remember to
               | watch out.
        
               | Someone wrote:
               | Yes, but assuming equal mass of radio active material and
               | identical radiation output something with a half-life of
               | 1000 years is less dangerous, radiation-wise (it still
               | might be more poisonous)
               | 
               | Caesium is often brought up in this kind of discussions.
               | I think one reason might be because it decays fast enough
               | to be harmful and still slow enough to be harmful for
               | considerable time.
               | 
               | Another reason might be that more of it gets released in
               | your typical nuclear accident. I wouldn't know whether
               | that is true.
        
               | bluGill wrote:
               | My point is about what is considered a long time, not
               | relative dangers. Caesium is bad for a few hundred years.
               | Some things are not as bad overall, but over the next
               | 10,000 years is worse. Caesium in fact has been through
               | one half life, and so is half as bad as it was at the
               | start.
        
               | Pyramus wrote:
               | Why would there be disagreement about what is considered
               | a long time? You are arguing that longer half life = bad,
               | shorter half life = less bad, which misses the point.
               | 
               | An effect with a shorter half-life could be a lot
               | worse/more dangerous/threatening (potentially
               | apocalyptic) than an effect with a longer half life.
        
         | cbmuser wrote:
         | They are. But you would have to eat 50 kilograms of these
         | mushrooms to get a dose of 2 mV which is the safe annual dose
         | for your average Joe:
         | 
         | >
         | https://www.bfs.de/DE/themen/ion/umwelt/lebensmittel/pilze-w...
         | 
         | > https://xkcd.com/radiation/
         | 
         | If you're a smoker, you're probably exposing yourself to higher
         | doses per year than anyone eating these mushrooms during
         | mushroom season.
        
           | tremon wrote:
           | I'm not sure what you're saying. Are you saying that one
           | needs to eat 50 kilogram of those daily to exceed the safe
           | annual dose, or that if one eats 50 kilogram over a year,
           | they'll have amassed more radiation from that single source
           | than is considered safe?
           | 
           | If the latter, is it safe expose yourself to more than
           | [annual dose/365] in a short time? Because 50 kg/year is just
           | 150 gram/day, and some people eat more than that in one
           | sitting.
        
         | amelius wrote:
         | Reminds me of atomic gardening, where the radiation is
         | deliberately introduced to perform mutation breeding:
         | 
         | https://en.wikipedia.org/wiki/Atomic_gardening
        
         | ipaddr wrote:
         | It is still contaminated because the half live is 30 years.
         | After 35 years it is half as strong. In 350 years it will still
         | be contaminated but it would have halved 10 times.
        
           | fastball wrote:
           | *300 years
        
       | yk wrote:
       | From the abstract of Morton & al. which is one of the studies
       | linked at the bottom:
       | 
       | > The 1986 Chernobyl nuclear power plant accident increased
       | papillary thyroid cancer (PTC) incidence in surrounding regions,
       | particularly for 131I-exposed children. [...]
       | 
       | > Radiation-related genomic alterations were more pronounced for
       | those younger at exposure. Transcriptomic and epigenomic features
       | were strongly associated with driver events but not radiation
       | dose. Our results point to DNA double-strand breaks as early
       | carcinogenic events that subsequently enable PTC growth following
       | environmental radiation exposure.
        
       | philmcc wrote:
       | Just saw this on my twitter feed, which gives the impression that
       | the conception date of the children could possibly affect it.
       | 
       | https://twitter.com/jenvcampbell/status/1386602322839674881
        
         | henryackerman wrote:
         | That would make sense. Embryos with bad genetic mutations are
         | quite often rejected. The mother does not even have to notice
         | this.
        
         | paganel wrote:
         | Thanks for sharing that, it was very powerful. I was lucky
         | enough to be born a few years before Chernobyl, but I have a
         | close friend who was born just after and who also has some
         | congenital non-standard body-related "things".
         | 
         | Maybe it is all a coincidence, fact is many (if not almost all)
         | of these individual stories haven't been statistically
         | collected and analysed, it's just a "hidden continent" of very
         | sad personal stories that will be forgotten once the affected
         | people will no longer be alive to tell them.
        
         | steeve wrote:
         | I feel for her struggle, but this is disinformation.
         | 
         | She starts with the false claim that the Chernobyl disaster
         | "killed hundreds of thousands of people". UNSCEAR (the IPCC of
         | radiation) puts the death toll at 50 people, + 6000 thyroid
         | cancers for those who were children at the time (due to
         | radioactive iodine sticking on the thyroid) [1]. This is why
         | folks who live near a nuclear power plant are given iodine
         | pills: to saturate the thyroid so it doesn't use the
         | radioactive one. This mostly useful for children.
         | 
         | She then attributes her defects on mutations originated from
         | radionuclides induced DNA damage. Unfortunately there is no way
         | to verify that claim, since there is no discernible health
         | effect under 100mSv/year, which her parents definitely were not
         | exposed to since they were in England.
         | 
         | [1] https://www.unscear.org/unscear/en/chernobyl.html
        
           | maratc wrote:
           | > She starts with the false claim that the Chernobyl disaster
           | "killed hundreds of thousands of people".
           | 
           | This claim is repeated e.g. by National Geographic on
           | Instagram [0]: "More than 100,000 people may have succumbed
           | to Chernobyl-related illnesses."
           | 
           | [0]: https://www.instagram.com/p/COGV1yzFkO-/
        
         | kingsloi wrote:
         | Thank you for sharing this.
         | 
         | Anecdotal, my wife and I became parents to a beautiful baby
         | girl in September last year. Our lil girl was diagnosed with
         | heart disease, and ultimately we discovered she has a rare
         | genetic disorder called Kabuki syndrome. She has many other
         | morbidities, turns out Kabuki affects multiple systems, heart,
         | kidney, hearing, spine, hips, endocrine, etc. We live in Gary,
         | IN. A few years ago there was a spill in Lake Michigan from one
         | of the steel mills. I was in the water on/around the time,
         | because the alarm wasn't raised for a few days. My child's
         | condition is so rare, that it took me a while to comprehend
         | really how rare. I questioned whether the two are related.
         | There have been studies about respiratory issues (asthma, heart
         | disease, etc.) near steel mills. I run a local website to track
         | our air pollution https://millerbeach.community, wish I was
         | able to track drinking water in real-time, because drinking the
         | same water discharged from steel mill sounds horrific.
         | 
         | https://www.in.gov/idem/cleanwater/resources/arcelormittal-f...
        
       | fallingfrog wrote:
       | You know, the feeling of surprise is the most important feeling
       | there is. It's a clue that somewhere in your network of facts
       | about the world, something doesn't fit.
       | 
       | Without surprise, you cannot learn anything new. Without surprise
       | there is no change. If you are never surprised then you are
       | stagnating.
       | 
       | I _welcome_ surprise. I enjoy it. It means that tomorrow I will
       | be smarter than I was yesterday.
       | 
       | What happens to a group of people when someone gets mocked or
       | downvoted for being surprised about something? What happens in a
       | school where you punish kids for speaking up in class with the
       | wrong answer? Nobody speaks up. Nobody takes the risk. Everyone
       | strives to be the same- same ideas, same stupidity. Boring. Give
       | me surprise any day over that.
       | 
       | Don't fucking _downvote_ me for saying I was surprised. That's
       | how a community dies.
       | 
       | It must be wonderful for those of you who _already know
       | everything_. But for those of us who don't, and prefer to try to
       | learn, don't try to rob us of the joy of being surprised.
        
         | rriepe wrote:
         | It should cost 1 karma to downvote.
        
         | PoignardAzur wrote:
         | Most communities welcome surprise, when it's signaled.
         | 
         | Saying "X is surprising, given Y" and then posting links to Y
         | doesn't signal surprise. It signals "I believe that X is false
         | and here is my evidence".
        
       | fallingfrog wrote:
       | This is a surprising finding, given that the increased number of
       | mutations in the wildlife around Chernobyl is well documented:
       | 
       | https://www.google.com/amp/s/amp.dw.com/en/nuclear-accidents...
       | 
       | https://www.thoughtco.com/chernobyl-animal-mutations-4155348
       | 
       | But, perhaps it's because the humans were exposed for a shorter
       | period of time before they were all evacuated.
        
         | maratc wrote:
         | The humans weren't eating the local (contaminated) produce, and
         | those who stayed -- due to their advanced age -- and were
         | eating it, probably weren't reproducing.
        
           | fallingfrog wrote:
           | Yes, that seems likely to be a large part of it. Maybe, the
           | takeaway is that radiation in food or taken internally is
           | more mutagenenic than radiation externally? Or that total
           | exposure matters more than acute exposure?
           | 
           | I called this a "surprising" finding and you know, surprising
           | findings are the bedrock of discovery. Sadly I seem to have
           | triggered a few people who can't handle the fact that the
           | world is an uncertain place we don't completely understand.
           | It must be hard to live in a world where being surprised is
           | so threatening.
        
             | maratc wrote:
             | It's hard for me to see why. It looks pretty much expected
             | that creatures that stay in contaminated areas and consume
             | contaminated food have more mutations than creatures that
             | don't. What's so "surprising" about it?
        
               | fallingfrog wrote:
               | Well, the radiation exposure was enough to kill several
               | of those workers outright, and the rest had hugely
               | elevated rates of cancer. In one instance the pregnant
               | wife of one worker spent too much time with him and the
               | radiation emanating from his body was enough to give her
               | a miscarriage.
               | 
               | And yet the article makes a very strong claim: all that
               | radiation didn't cause any rise in birth defects at all!
               | That's surprising. It certainly caused defects in the
               | animals in the area, who didn't have the insanely high
               | exposure as the workers- albeit the workers were exposed
               | for a shorter time.
               | 
               | So something is going on here which I freely admit I
               | don't completely understand.
               | 
               | I just thought of another possibility: all the workers
               | who suffered that exposure were men. Perhaps, radiation
               | on a developing fetus is mutagenic, but radiation
               | exposure in sperm is less so, maybe the sperm that
               | develop after the acute exposure is gone are normal!
        
               | maratc wrote:
               | > the radiation exposure was enough to kill several of
               | those workers outright
               | 
               | I gather no wildlife took part in putting the fires off.
               | 
               | > the pregnant wife of one worker spent too much time
               | with him and the radiation emanating from his body was
               | enough to give her a miscarriage.
               | 
               | Did you see that in the HBO Miniseries?
               | 
               | "Lastly, there is the dangerous representation that,
               | because one of the victims was radioactive, his pregnant
               | wife endangered her unborn child by entering his hospital
               | room. First, as discussed, none of the victims were
               | radioactive--their exposures were almost exclusively
               | external, not internal. More importantly, risk to a fetus
               | from an exposure like this is infinitesimally small." [1]
               | 
               | [1] https://cancerletter.com/filmtv/20190524_3/
        
       | johndoe42377 wrote:
       | Why would they? The probability that a damaged by radiation copy
       | of a gene ends up in a spermatozoa which wins the lottery is
       | zero.
        
       | macinjosh wrote:
       | Encouraging news! What a tragedy Chernobyl was. Both in the lives
       | lost and those forever altered by the event.
       | 
       | Compounded on that is also the humongous set back it contributed
       | to for no-carbon energy. Now we are at a point where some
       | congressional leaders are telling us the world may end in as soon
       | 12 years[0] because of the man-made climate emergency. Since the
       | situation is that dire perhaps the small risks of modern nuclear
       | energy are a better alternative?
       | 
       | [0]: https://www.youtube.com/watch?v=oHk8nn0nw18
        
         | throwawayboise wrote:
         | Why do you assume congressional leaders have any expertise that
         | qualifies them to be taken seriously on climate issues?
        
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