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It is known that melanin protects against UV radiation.

But say a nuclear bomb dropped somewhere would more people of dark complexion survive the radiation burns because the melanin would protect them?

Or as another example, suppose there was a meltdown and someone had to swim into the reactor to pull out the core, would it be best to send the light skinned or dark skinned person to ensure maximum chance of survival? All other things being equal.

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The absorption of gamma and x-ray radiation by skin is negligible, so the amount of melanin present is irrelevant. Stopping high energy photons requires a lot of mass, not a few microns of melanin.

Edit:

I think a citation that x-rays and gamma rays go through skin is unnecessary (they'd be useless for imaging bones otherwise), but NIST has tabulated values for different tissues as a function of photon energy if anyone wants to double check:

https://physics.nist.gov/PhysRefData/XrayMassCoef/ComTab/tissue.html

As expected, x-rays have absorption path lengths on the order of centimeters to meters in soft tissues, which is why you can use them to image through skin.

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  • $\begingroup$ interesting. There was an article about a mould that was inside a nuclear reactor, and they said it survived because it had high levels of melanin $\endgroup$
    – zooby
    Feb 5, 2020 at 3:32
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    $\begingroup$ @zooby Were you thinking of this? en.m.wikipedia.org/wiki/Radiotrophic_fungus $\endgroup$ Feb 5, 2020 at 3:41
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    $\begingroup$ @LifeInTheTrees What is wrong? It seems like you agree with my point that high energy radiation penetrates deep into skin due to low absorption. $\endgroup$ Oct 15, 2022 at 12:50
  • $\begingroup$ Yes sorry I misread the first statement, i'll delete it, i upvoted previously. There is a difference caused by melanin at least for beta radiation. $\endgroup$ Oct 15, 2022 at 19:49
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Maybe not much of an immediate advantage, but evolutionarily, I mean...according to the article below, the melanin in frogs with darker skin was enough to sway natural selection and drastically reduce the population of green frogs while the population of black frogs flourished https://www.livescience.com/black-frogs-evolution-chernobyl?utm_source=facebook&utm_medium=news_tab

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    $\begingroup$ An answer should stand of it own and not consist of a link. References are for for further reading. Please edit your answer accordingly. $\endgroup$
    – Chris
    Oct 12, 2022 at 18:18
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Ken Mac is correct, melanin has an effect and you should also consider fatty people to be the heroes of your scenario.

Melanin can cause more surface burns compared to a person with light skin and good fat coverage.

Here's a study that states that black people complain of skin problems more often during radiation chemotherapy.

also this research:

Human and animal heterogeneity in terms of skin tissue distribution and impact on radiation dose distribution:

In humans, subcutaneous skin thickness and body fat vary as a function of age, sex and ethnicity. Fat tissue thickness can lead to wound variability, especially in the case of beta radiation, and the presence of MSCs in the adipose tissue could alter the response. Therefore, care must be used in selecting a model that minimizes these variables. In pig and mouse models, there can be different healing rates based on what part of the skin is irradiated. For example, in the pig, thicker dorsal skin heals differently than the thinner ventral skin. Mice also have similar skin location differences, in that radiation-induced damage can be very different in that of leg skin compared with that of ear skin. Proximity of the radiation exposure to bone can play a role in the extent of damage. Effect of skin melanization in view of possible differential radiation responses due to higher levels of melanin, as well as challenges involved in scoring erythema in pigmented skin: Concerning the use of a pig such as the Duroc, which is more heavily melanized, differential sensitivity to high-energy radiation may be observed due to the presence of melanin.

The physics forum would know, the radiation types are so variable. Older style atomic bombs had flash burn from the explosion and the fallout from the sky aftewards, i.e. in bomb tests near the Marshall islands.

Marshall islands research.

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