Not dangerous unless broken up and
    ingested, but need to be kept out
    of the food chain.

I say that only bring to your attention how difficult this would be in practice. Putting safety aside for a moment, in most countries the regulatory restrictions are enormous because they are signatories to the NPT—Treaty on the Non-Proliferation of Nuclear Weapons which tightly bind them to how they use and handle nuclear materials. This involves, use, tracking, short and long-term disposal thereof not to mention how to keep radioactive materials away from bad actors/those who've ill intent.

With safety, there are so many issues involved that I can hardly even mention them here. Just as an illustration, the once lack of regulations covering the manufacture and use of luminous radium paint turned out to be a disaster.

I've thought about this a great deal, whenever the batteries in my flashlight die I wish I had some nuclear powered ones and evey time I'm brought back to reality when I think how difficult it would be to implement in practice.

There are no hand held devices which will tell you if the soil you're vaguely near has heavy metals in it, nor how much.

Well, technically, there are, but now you're back in the ionizing-radiation business: https://www.youtube.com/watch?v=KdfHVcU8U7U

Personally, I've a healthy respect for radiation/nuclear materials but I'm not afraid to work with them so long as I know what I'm dealing with—and that's the key point. It'd be a bit pretentious to describe situations where I've been exposed to radiation levels above background except to say they were deemed occupationally safe. That said, I've always avoided such situations when and wherever possible.

Let's put my view into perspective: here's NileRed (a YouTube channel I like and watch often) making uranium glass in his home lab: https://m.youtube.com/watch?v=RGw6fXprV9U.

Note: I'd never do this despite the low level radiation because of the potential for breathing in uranium dust, albeit a small risk. That said, I nevertheless own several old wine glasses made from uranium glass which I keep not to use for drinking but as a demonstration of how uranium glass fluoresces under UV light.

It's very difficult to put information about radiation into proper perspective or in ways that the lay public can properly understand and appreciate, thus the need for tight regulations. Then, as I mentioned, there are the bad actors and of course a small collection of damn fools who are a danger not only to themselves but also to others.

No doubt, you're right about cadmium and traces of it in food. That comparison isn't lost on me either. It just so happens at another time I ran a business maintaining handheld portable cassette recorders of the type used in exhibitions, etc. and they used rechargeable NiCd batteries that needed replacement. It was not unusual for me to have to dispose of upwards of 500 old, often leaking batteries. Being concerned about Cd contamination and disposing of it in an environmentally-friendly manner was just part of the job.

Contamination from heavy metals is a very real problem and it's not only Cd but also Pb, Tl, Hg, As and orhers. Moreover, assessing the actual risk can be very difficult and depends very much on circumstances.

Like its more notorious mate mercury, cadmium is a poisonous heavy metal, nevertheless that hasn't stopped it from being used in industry for plating etc. (passivated cadmium plating makes a very nice surface). Thus, in the recent past cadmium has been deemed safe enough for these purposes in the same way mercury was considered safe enough for tooth amalgam/fillings. That said, just add a couple of CH3 methyl groups to Cd and we get one of the most diabolical poisons available—dimethylcadmium (same goes for Hg—dimethylmercury). Fortunately, these diabolical compounds aren't that common so we must take that into account when assessing the dangers of these heavy metals.

Heavy metals are everywhere in the environment both from natural sources and from pollution, so when assessing the risks several factors predominate, concentration and their potential for forming compounds that are far more toxic than are the base metals. Also, these compounds are often soluble which adds to their danger.

BTW, it's often been said that one cubic meter of soil from the average backyard has enough naturally occurring arsenic to kill someone—or at least sufficient to make them very sick. I've never seen assays to prove that one way or other but assuming it's true it puts the risks from heavy metals into perspective.

Or just walk to a number of known sites in Utah and pick up chunks of ore off the ground.

A real danger IMO with Alpha and Beta emitters is that most Geiger counters aren’t going to pick them up at all - most are only meaningfully sensitive to Gamma.

I'm in Australia and there's no shortage† of the stuff here. Moreover, mining it has always been politically controversial.

Whilst it wouldn't happen now, when I was at school decades ago we had radioactive sources in the science lab and we did experiments showing how alpha rays could be stopped by paper, beta with tin foil and so on.

I also recall the lab had a round section of metallic uranium a bit bigger than a US silver dollar and about twice as thick, it was handed around the class for all to feel how heavy the element was. It was also a source of radioactivity for our Geiger counter (but not the only one).

To some degree, we have to be pragmatic about access to such materials but I'd be the first to agree that finding the right balance is difficult. Scaring everyone out of their wits about radioactivity is counterproductive (as we've seen in recent decades), similarly overfamiliarity is as equally dangerous.

I'm glad I had that early experience at school together with proper instruction that put its dangers into perspective.

The same went for mercury which we had at school in reasonable quantities. We were taught its dangers and to be very careful with it, especially so its compounds.

In recent times I've met young people who've never actually seen mercury and who are terrified of even the mention of it. Clearly no one ever wants a repeat of the Minamata tragedy but being scared of elemental mercury to this extent isn't right either.

I've often said our best approach is proper education, that is by providing factually accurate information from early on.

Seems to me in recent years we've not done a particularly good job at doing that.

__

† https://en.m.wikipedia.org/wiki/Uranium_mining_in_Australia

https://en.m.wikipedia.org/wiki/Radium_Hill

I think it's telling that the big health disaster everyone remembers happened like a hundred years ago and occurred not just before regulation, but before the danger was even understood. There are negligible annual deaths in the US from either acute radiation exposure or nuclear-material-related chronic radiation exposure.

All up there are at least seven or eight fatalities in US reactor | research facilities in that general time frame, Los Alamos National Laboratory, et al.

The Columbus radiotherapy accident 1974-76 led to 10 deaths and 88 "immediate severe complications"

There was another in Houston in 1980 with 9 deaths and additional complications.

https://en.wikipedia.org/wiki/SL-1

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

REAC/TS Radiation Accident Registry: : https://www.irpa.net/irpa10/cdrom/00325.pdf

I've had a career mapping environmental radiation across entire countries; background uranium, potassium, and thorium and residual traces from testing, mining and accidents.

Deaths are rare in the US, a bit more common elsewhere, that's a fact.

I can't say that's an argument for relaxing standards or being less safety conscious in reactor design, building codes, or medical and industrial procedures.

The Union Carbide Corporation (UCC) of the United States demonstrated pretty well what can happen if you shirk safety and that was just manufacturing pesticides.

There's always that one meteorite.

Mind you, there's a steady supply of radoactive waste from rare earth processing that gets offshored and swept under the carpet .. it's okay to have an addiction to fancy electronics gadgets, less so to be ignorant of by products and the harm caused in other peoples backyards.

> There's always that one meteorite.

But we just ignore the meteorite. Nobody has made any attempt to stop either of us being hit by a meteorite. We just let it fall where it may.

We've had safety standards shirked, we've had multiple disasters and the worst case scenario so far appears to be order-of-magnitude equal to a normal year of current practice using fossil fuels. It seems to be well within our tolerance for risk.

The issue here is that progress on one of the most promising sources of energy we have has been blocked and it is hard to find someone who can articulate a reason why, let alone a good reason. Between Germany and Japan we've had countries that appear to be more willing to risk deindustrialisation than just keep on with a perfectly acceptable nuclear status quo. It is madness. It is akin to trying to move civilisation underground to avoid the inevitable meteor strike that is going to wipe out humanity - we can't afford that expensive a risk mitigation and it doesn't seem clear that it would even help.

South Korea has fast build times, China has 100 reactors planned with 10(?) (IIRC) currently under construction, a large MW scale pilot SMR completed and tested for a year, ground broken for a low GW 2nd gen salt reactor based on the pilot, and plans for a large high GW third gen version waiting on the 2nd gen being completed and bedded in for any modifications to plan.

The economics vary by country and demand, here in Australia there's no economically feasible near term path for nuclear power gen. for a number of good reasons, not the least being the short term return from putting any available money into renewables and batteries - but this is a particular economic constraint setup that differs to other countries.

> I can't say that's an argument for relaxing standards or being less safety conscious in reactor design, building codes, or medical and industrial procedures.

It's prima facie evidence you're picking the wrong trade-off between safety and productivity. Because of the nature of diminishing returns, the optimal point in a cost-benefit trade-off usually results in both non-negligible cost and non-negligible benefit. When your safety regs are so strong as to have driven risk to ~zero, but where the compliance cost of the regs are reflected in every aspect of the industry, there ought to be a presumption of over regulation that would need to be rebutted quantitatively. It's irresponsible to set degree of regulation without estimating the costs of compliance.

it's extremely difficult to evaluate industry (broad industry, not just nuclear) safety value on the basis of deaths that have occurred without a solid understanding of the deaths and other costs that can occur should standards be relaxed.

The analysis on various Los Alamos et al. National Laboratory incidents during the early atomic days reveals that things easily could have been much worse, rather than three dead greater numbers could have been killed and expensive facilities rendered unusable. Carrying live but "safe" nuclear weapons about came razor close to accidental detonation on US soil near civilian population centres on a few occassions - these make studies for whether safety procedures were justified in time and expense or perhaps barely went far enough.

I raised Union Carbide Corporation as an example of what can happen in an industry if safety isn't headed, such accidents can happen in many industries and some have the potential to "salt the earth" for many many years past an event that immediately kills large numbers.

    Timing Toast

    There's an art of knowing when.
    Never try to guess.

    Toast until it smokes and then
    twenty seconds less

This can be difficult to do in practice.

Some coal related pollution deaths can easily fall under indirect deaths due to radiation.

By all means lookup and answer your own question, HN threads benefit from solid figures and linked sources.

That's putting the cart before the horse.

Those regulations came to be because of things like that (plus also "we don't want everyone getting nukes or radioisotope weapons" because this is more general than just industrial accidents).

The only way to compare is to look at times (or places) without the legislation.

We consider it safe because it’s tightly controlled and very centralized, but that has no connection to how safe it would be as a consumer product. Just because it contains the same material, doesn’t mean anything, because the methods of harm that could emerge have never existed.

Ingestion, trash disposal, recycling contamination, the infinite ways you could accidentally destroy a device.

If you are contaminated internally, with radioactive dust then there is no way to fix that.

“Rising rates of cancer in young people prompts hunt for environmental culprit (ft.com)”

https://news.ycombinator.com/item?id=41178776

> 3-4 orders below the power requirements for a phone. An AirTag-type intermittent device, though...

If my maths is right (and it's past midnight, and I'm not entirely sober, so might not be) and my search results are too, 15 x 15 x 5 cubic millimeters is approximately 9.68 times smaller than an iPhone battery (95 mm x 37.6 mm x 3.05 mm, ish), but if energy capacity scales linearly to volume then its ~12,500 times lower capacity per volume than an iPhone battery.

But, still, only 80mah a day . So 750mah scaled up to iPhone battery size. So abut 1/5 of the average daily power requirement for an iPhone. Even at that rate you’d need to use a supecapacitor to even out the load profile.

OTOH, in terms overall energy, it would be about the same as about a 50 litre lithium ion so it is rediculously dense, just low output

> "By 2015, PixelQi's team and offices were unreachable, and the company is presumed defunct.[3] The intellectual property is now owned by the original investor of Pixel Qi, while the right to manufacture Pixel Qi technology contractually rests with Tripuso Display Solutions.[4][5]"

https://en.m.wikipedia.org/wiki/Pixel_Qi

It could be made to work if software wasn't so violently inefficient (both CPU and data usage) and screens weren't so large.