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Comment by candiddevmike | Hacker News Reader

ARS has to be one of the worst ways to go, and probably the most unnatural?

It's an interesting topic, what would be the most unnatural way to die.

At some point, I got in a conversation about what would happen if you drank nothing but heavy water. The short answer is that yes, this would kill you; the differing molecular weight between molecules built with heavy hydrogen and regular hydrogen will eventually add up to disruption of metabolic processes in ways that we haven't even researched. But we haven't researched them because it would cost an absolute fortune to get enough of the stuff to do yourself in.

This would be a suicide reserved for billionaires.

Heavy water's only about $1000 a litre in bulk. Certainly cheap enough to run experiments on rats and small plants. Such experiments have been done. That's how we know it'll kill you.

Its toxicity profile is kind of interesting. In almost all eukaryotes (plants, animals, fungi) low concentrations (1 - 10%) seem to have no obvious effect at all, while around 25% it seems to cause temporary sterility - the gametes seem particularly sensitive. As it approaches 50%, cell reproduction stops and death is rapid. Very few eukaryotes can survive >50% heavy water in their cells. Though a few types of yeast and single-celled plants seem to be able to survive in conditions like many bacteria can - up to 95% or more heavy water. But all kinds of life die at 100% heavy water, as far as I know.

https://en.wikipedia.org/wiki/Heavy_water#Effect_on_biologic...

Surely not that much. The LD50 of heavy water is really high at 30% of body weight[1] but it's only about $10,000 per kg. So even the most obese millionaire should be able to kill themselves this way if they really want to.

That's part of why thermonuclear weapons have such a disturbingly high "bang for the buck." The enriched uranium or plutonium primary is really expensive. So is the rocket that gets it where it's going. But the lithium deuteride that makes up the fusion fuel is comparatively dirt cheap.

[1]https://arxiv.org/pdf/physics/0206076.pdf

> That's part of why thermonuclear weapons have such a disturbingly high "bang for the buck." The enriched uranium or plutonium primary is really expensive. So is the rocket that gets it where it's going. But the lithium deuteride that makes up the fusion fuel is comparatively dirt cheap.

No idea what the cost of enriched U, Pu, or lithium deuteride is, but I'll note that A) current day thermonuclear warheads deliver an estimated 50% of the total output through fission of enriched U (casing) and Pu (primary) B) the lithium in lithium deuteride, as well as the deuterium, need to be enriched, so probably not quite dirt cheap (depends on your definition of dirt cheap I guess)?

As an aside, it's surprising how "safe" plutonium can be even when it's being injected into your bloodstream

https://en.wikipedia.org/wiki/Human_radiation_experiments

https://en.wikipedia.org/wiki/Albert_Stevens

The toxicity of heavy water is not related to its molecular weight, rather to the difference in strength of its hydrogen bonds.

I was under the impression that the difference in mass results in slowing down metabolic processes (mainly because it takes more energy per unit time to move a more massive molecule). I wouldn't expect the hydrogen bond strength to be affected because hydrogen bonds are electromagnetic bonds, and the electromagnetic properties of deuterium and (H1) water are the same (other than the mass-effected ones; heavy hydrogen in an electric field will accelerate more slowly than light hydrogen, but that's because it's more massive, not because it's more weakly coupled to the electric field).

Heavy water hydrogen bonds are a couple percent stronger because the molecules themselves are very slightly smaller. Smaller molecules result in a shorter range of vibration at a given temperature, hence less inherent "fighting" of the hydrogen bond.

I think it’s probably tied with dying from obesity for being most unnatural.

idk about "unnatural", it's basically death by physics. You are killed by the universe. Sounds natural to me.

I'd put in the same category as falling from a great height.

One way to categorize, I guess.

Prior to humans enriching radioactive materials, how many humans died from ARS vs. falling from a great height?

Well, if we want to put it that way, all deaths are death by physics, aren't they? Including murder.

> I'd put in the same category as falling from a great height

Yeah, onto the surface of the sun.

What other kind of death is there?

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