Black sand, hot beaches: Welcome to Brazil's radioactive beach town

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40 micro-Sievert/hour is not at all insignificant. An hour on the beach is equivalent to two chest X-rays or a single flight from LA to NY.

Bonus points for bringing a radiacmeter to the beach. I’m glad I’m not the only one!


xkcd link

(and yes there’s a banana ‘to just look at’ around 0.1 μSv)


Based on that chart and the dose rates shown in the video, living on that beach for a year would yield three times the dose clearly linked to increased cancer risk.


[J. Frank Parnell has entered the chat]


There’s speculation (which I’m not qualified to comment on) that low doses of radiation can boost the immune system. And lack of radiation suppresses it.

For example, we don’t see elevated cancer rates in cities with high levels of background radiation.

CNL (Canadian Nuclear Laboratories) are currently conducting low level radiation studies on stem cells.

I do think that the impact of radiation can’t possibly be linear though… I’m not a doctor, I don’t work in radiation, but it seems a lethal dose is non-lethal if delivered over an extended period of time. The current LNT model does not take “over time” into consideration, instead assuming all doses are cumulative.

Certainly many anti-nuclear activists have repeated this claim. That doses are cumulative. I think that is like arguing that walking down a skyscraper’s stairwell is equivalent to jumping off. We have cellular repair mechanisms which either get overwhelmed, or do not.

People going there for ‘a cure’; sounds like the old ‘health mine’ therapy where people used to go (and in some places, still do) to breathe in low levels of radon to ‘cure’ conditions like arthritis. There were once several mines in Montana that offered the service and at least one in Germany is still going.

So-called ‘radium springs’ became a popular therapy in what is now Czechia early in the 20th Century. There was a popular belief that low levels of radiation were a tonic - more scientifically called radiation hormesis - and that led to some crazy dangerous ideas like Radithor ‘medicine’ and Doramad radioactive toothpaste.

Naturally, there’s a Tom Scott video (and an interesting paper linked in his description of the film) about radon therapy:


If you take one slice at a time off a loaf of bread, you’ll never finish it.

Or probably a bit more accurate:

If you break one window at a time on a skyscraper, they’ll never be all broken. They’ll get fixed, at least until the repair guy gets overwhelmed.


tanning my idol GIF


most of the electricity is from hydropower, so it is a win-win
great job green energy

What are you on about?

Welcome to BoingBoing


It reminds me of that OK town on some freeway where the kids sledded, and the 4th of July picnics took place on a big slag heap of leaded ore for a good some 20-30 years; thanks to an indigenous tribe I can’t recall because that’s how mental illness flows, is burying it as we speak, and yet nature finds a way regardless. this planet sucks.

I think I just said hello

I’m not so sure cellular repair is that simple for cells that become cancerous, or DNA that has been damaged by radiation.



Neat. If someone goes, can you get me a sample?

Many years ago someone sent me some black and white sand from Tenerife - a place I hadn’t heard of before.

The black sand was volcanic, and the white I think they said was imported?


If you get a severe sunburn you’re elevating your risk of skin cancer.

If you get a consecutive series of tans due to the same amount of sunlight being spread out over time, you might still be raising your risk, but absolutely not as much as the single severe sunburn.

I don’t remember black beaches in Tenerife but I have been on them in Fuertaventura and Gran Canaria and yes, the islands are volcanic. Lots of volcanic rock around and all that. The blonde sand is blown in from Africa though rather than literally imported. The wind from the Sahara can occasionally lead to significant deposits even as far away as Ireland. Well significant in the sense that your car gets filthy, not like you get a new beach. The tide does that.


Oh, ok, That is what they meant. Filing that nugget away in the brain.

I took a crappy digital microscope to them to look at the grains and how they differed. The blond sand was much rounder and weathered.

Evidently, there are several black sand beaches!


And yet…