> The report indicated radiation levels at "13.9 mR/hr" where the buckets were stored, and "800 mR/hr" on contact with the ore.
> [...] The commission lists a maximum safe dosage for the public, beyond natural radiation, is no more than 2 millirems per hour, or 100 per year.
Regulatory Limits for Occupational Exposure
Many of the recommendations from the ICRP and other groups have been incorporated into the regulatory requirements of countries around the world. In the United States, annual radiation exposure limits are found in Title 10, part 20 of the Code of Federal Regulations, and in equivalent state regulations. For industrial radiographers who generally are not concerned with an intake of radioactive material, the Code sets the annual limit of exposure at the following:
1) the more limiting of:
A total effective dose equivalent of 5 rems (0.05 Sv)
The sum of the deep-dose equivalent to any individual organ or tissue other than the lens of the eye being equal to 50 rems (0.5 Sv).
2) The annual limits to the lens of the eye, to the skin, and to the extremities, which are:
A lens dose equivalent of 15 rems (0.15 Sv)
A shallow-dose equivalent of 50 rems (0.50 Sv) to the skin or to any extremity.
The shallow-dose equivalent is the external dose to the skin of the whole-body or extremities from an external source of ionizing radiation. This value is the dose equivalent at a tissue depth of 0.007 cm averaged over and area of 10 cm2.
The lens dose equivalent is the dose equivalent to the lens of the eye from an external source of ionizing radiation.
This value is the dose equivalent at a tissue depth of 0.3 cm.
The deep-dose equivalent is the whole-body dose from an external source of ionizing radiation. This value is the
dose equivalent at a tissue depth of 1 cm.
The total effective dose equivalent is the dose equivalent to the whole-body.
Declared Pregnant Workers and Minors
Because of the increased health risks to the rapidly developing embryo and fetus, pregnant women can receive no more than 0.5 rem during the entire gestation period. This is 10% of the dose limit that normally applies to radiation workers. Persons under the age of 18 years are also limited to 0.5rem/year.
Non-radiation Workers and the Public
The dose limit to non-radiation workers and members of the public are two percent of the annual occupational dose limit. Therefore, a non-radiation worker can receive a whole body dose of no more that 0.1 rem/year from industrial ionizing radiation. This exposure would be in addition to the 0.3 rem/year from natural background radiation and the 0.05 rem/year from man-made sources such as medical x-rays.
Most places moved to 20mSv now and use 50mSv for short term (100mSv is detectable chance of cancer developing). Average US worker exposure is ~2mSv/yr.
What I found very interesting was that the levels were slightly lower in the air near the ground than on the ground where I landed.
Downvoters need to pick up a geology book.
How much impact does radiation has on our cancer rates we at the moment?
I mean, i would accept the risk of flying and getting a xray but i would probably try to choose my building materials differently if it would make sense.
At this late stage, that is probably an impossible goal to meet.
* 800 mR/hr if you touched the ore
* 280 mR/hr on the surface of the bucket (sealed)
* "0 above background" if you were 5 ft away from the bucket
* 2.5 mR/hr if you were touching the cabinet it was in
 - https://www.azcentral.com/story/news/local/arizona/2019/02/1...
I’m wondering why they used R instead of Sv though. It’s a single source with a single quality factor, and were only concerned with the impact on humans.
Roentgens can be assumed to safely equal RADs (although they don't, conversion is less than 1 for kV), the historical unit for "Radiation Absorbed Dose." For photons this would be equal to REM "Radiation Equivalent Man."
All old units; conversion to S.I., 100 rad = 1 Gray (J/Kg), 100 rem = 1 Sievert.
Essentially, who ever wrote the report was old and conservative.
The occupational risk is also essentially nil. This is much ado about nada.
A properly sealed 5gal bucket will remain air tight even if it's bouncing around inside a tote in the bed of a truck on rural gravel roads for ~10mo (the tote flooded at some point but the bucket wound up dry).
Sitting in a cabinet the risk of dust making it out of the bucket would have been nonexistent so long as the lid was on it.
* One chest CT per hour for touching the ore (or about 9 hours touching the ore to reach your annual max dosge)
* One head CT per hour for touching the bucket
* nothing for 5ft away
* One chest XRay per hour touching the cabinet (less than a cross-country flight LA <-> NYC)
A dental X-ray is like eating 50 bananas, and half of what you would get over the course of a normal day.
And the record most in 1 minute is “only” 8.
>The Nuclear Regulatory Commission measures radiation contamination in millisieverts per hour or per year. According to Stephenson, close exposures to the uranium buckets could have exposed adults to 400 times the health limit — and children to 4,000 times what is considered safe.
* 280-320 mR/hr if you physically touched the bucket(s)
* 13.9 mR/hr if you were within 5 ft
* 1.85 mR/hr inside the building more than 5 feet away. Also can be thought of as "0 mR/hr above background"
* 2.02 mR/hr outside, in the park, on a bright sunny day.
2.02 is "background". i.e. the levels everyone is getting from natural sources outside.
13.9 mR/hr is 139 microsievert (µSv) per hour
So, really its that being near the buckets was 139 µSv/hr. A child would get ~70 µSv in that half hour, in theory.
If we believe Randall Munroe's (of xkcd fame) sourcing in https://xkcd.com/radiation/, then that means the kid got less than a round-trip flight from NY to LA sitting there for 30 minutes. "1400 times" sounds like one heck of a scare tactic. Not saying this was smart, but its overly alarmist.
Numbers are from a picture I found. Scroll down a section on "Takeaways from the report" where it summarizes the exposure.
(That's what the comparison with sunlight is aboot)
We went in via Horseshoe Mesa. There are signs near the campground on Horseshoe Mesa warning you to stay out of areas where there was mining activity. We shoved on from there because our permit for the night was for further down rather than any concern about radiation.
More titillating is the warning in the backcountry hiking guide for the Tonto Trail from the Bright Angel Trail to the Hermit Trail:
"There is water in the bed of Horn Creek about half the time, but unfortunately it is radioactive so don't drink it unless death by thirst is the only other option. The source of the radioactivity is a deposit of high quality uranium contained within a collapsed cave system geologists call a breccia pipe." 
> at levels he calculated to be 1,400 times the Nuclear Regulatory Commission's safe level for children.
Note that it doesn’t mention the timeframe that the children would have to be exposed to the buckets to get that number. It mentions 30 minutes earlier, but it’s unclear whether 30 minutes was used to get the “1400 times” figure.
If you hike around the Grand Canyon you are going to be exposed to Uranium. There are a lot of mines in and around the place (see here: https://www.grandcanyontrust.org/grand-canyon-uranium). It really isn't something to worry about unless you want to live their and/or eat food that has been contaminated.
These folks may have covered up something that resulted in the miscarriage, or birth defects of the child of any pregnant woman who stood near that closet for just a few minutes.
I think the folks who covered it up for 8 months, or the morons who (threw the rocks in a hole and brought the nuclear-contaminated buckets back) should lose all their power and position. That is an amazingly bad decision.
Lucky thing some kid walked around with a geiger counter. He recorded the levels, so the numbers that officials are hiding, he knows them. His counter can be tested and certified by a decent national lab, and the exact and calibrated level of the radiation determined. And those contaminated buckets tell something about the material that was in them.
Ore shmore. It is a radioactive substance that gives off dangerous levels of alpha, beta, and gamma radiation, as well as nuclear byproducts like radon and other gaseous nuclear isotopes.
Get more than the "top paragraph summary" that NPR did on the original AZ Central article by reading it in its entirety.
Neither the linked article nor your's said anything about what kind of "geiger counter" this kid had; whether it was something picked up off ebay, an old civil defence unit, or some kit or custom made thing from Electronic Goldmine (a native AZ electronics surplus and education kit supplier - https://www.goldmine-elec-products.com/)...
It's very well possible that the kid has no real numbers; that is completely unknown.
I'd be willing to bet you could walk into an old mining bar in Flagstaff and have more exposure to natural radiation used in the building materials than you'd experience from these buckets of old ore. Natural radiation sources like these are all over the place in Arizona.
The only real danger I could see and understand, though, is whether these buckets were covered or open; could someone or a kid have "dug through them" with their hands, or been in closer proximity to the material inside - where the dust or whatnot could be left on their hands to be ingested or inhaled in some manner.
That would be a much different situation than merely being near it for a small amount of time.
This by far would be my number one concern. Proximity doesn't seem to be much to worry about (238-Uranium has an alpha decay and doesn't travel far in air). But inhaling or ingesting radioactive material completely changes the danger level.
> Natural radiation sources like these are all over the place in Arizona.
Or... Grand Central Station. But... you have to consider context, which a lot of reporters don't. Consider this quote.
"It's worth noting that if Grand Central Station were a nuclear power plant, it would be shut down for exceeding the maximum allowable annual dose of radiation for employees."
Yikes! We can trace down the dosage level to 120mrem/yr (1.2mSv), which we can indeed see is on the order of average dosages for radiation workers  or 1/20th of the allowable dosage! BUT we can look at  more and see that 100mSv is "Lowest annual level at which increase in cancer risk is evident (UNSCEAR)" (threshold model).
So when I see articles like this I'm always a tad hesitant to even read them. They frequently focus on the first part of the last paragraph and give no indication to what these things mean. Or even worse, are misleading like that gizmodo article (I would in fact call this dangerous reporting). Radiation quotas are purposefully (and I agree with this) put to be far below what one might also call "safe" (I'd _upper bound_ "safe" as <100mSv/yr but think most would agree 20mSv is "safe"). Yeah, we should pay attention and not expose ourselves to radiation unnecessarily, but let's also be realistic about the danger (especially when we're in such dire need if we're going to solve our climate problem).
 https://jciv.iidj.net/map/ (just for fun, now that we have some understanding of what these numbers mean).
> ...something that resulted in the miscarriage, or birth defects of the child of any pregnant woman who stood near that closet for just a few minutes.
If we really are talking about a couple of buckets of uranium ore, then no, standing near them for a few minutes will not cause miscarriages or birth defects. Even the AZ Central article, in the midst of its fear mongering, says, "Just 5 feet from the buckets, there was a zero reading." The rest of the article is no more helpful, giving not nearly enough context to the cited measurement for readers to draw any conclusions.
> It is a radioactive substance that gives off dangerous levels of alpha, beta, and gamma radiation, as well as nuclear byproducts like radon and other gaseous nuclear isotopes.
Radon yes, and as I learned from another HN thread regarding this same story, radon can be generated at much higher rates than I ever realized. However this is highly unlikely to affect anyone who didn't spend extended periods of time in an enclosed (or sub-grade) space with the ore.
Gamma radiation here wouldn't be significant. Alpha radiation is stopped by mere inches of air. As with alpha, beta radiation is only hazardous if the material is inhaled or ingested. And aside from radon, there are no gaseous elements in uranium's decay chain.
I suppose, if the rocks were chalky and they were taken out the bucket and played with frequently, there could be some kind of inhalation risk. On the other hand, mineral dust is heavy, and typically settles out of the air too quickly to be a significant inhalation hazard. We see something similar with lead, where leaded dust from paint and vinyl mini-blinds is mainly a hazard to babies and little kids who can get their faces right in it, or eat things off floors and window sills.
Otherwise, it's hard for me to imagine how this material could have posed a health hazard to visitors.
But yes, much granite does contain substantial K-40 (as do we) and some (probably less than 10%) is a substantial source of radon. Also thoron, but it's too short-lived to accumulate. You can buy test kits designed to measure radon production rate from surfaces. The radon gets captured on activated charcoal. You return the kit(s) to the provider, and they send you results.
Not nearly as interesting as the radioactive boyscout story:
David Hahn sadly passed away at 39:
Geeze, I wanted to look up him, thinking he'd have gotten an engineering scholarship or something. Looks like he served in the military, but afterwards he got addicted to drugs and died in his late 30s. ... .. Geeze that's fucking tragic.
It cost ~$650, but that's because it uses a very high-end geiger tube, and can detect alpha and beta in addition to gamma radiation. Comparable commercial devices do apparently cost a couple thousand.
Low and behold, the desert rocks weren't radioactive. However, taking the counter on an airplane was quite shocking, and gave the cabin crew real concern.
Concern about radiation exposure or concern about the mysterious-looking device you whipped out mid flight? ;)
Realistically though most things aren’t radioactive in a meaningful way.
This paragraph didn't make sense to me:
"Photos provided to the newspaper by Stephenson show technicians arriving in June 2018 to take away the buckets of uranium ore. The technicians reportedly dumped the buckets at an old uranium mine 2 miles away, then for some reason brought the buckets back to the building."
I'm guessing they mean "dumped" the contents of "the buckets"
Because of that uranium is radioactive and that radioactivity is harmful, but is not the primary harm, unless you are allergic to uranium at which point the radiation is the primary harm. Also, sensitivity to radiation varies wildly by person. Uranium is a high density metal that has some dissolution capability into water, like lead, which means heavy metal poisoning. Uranium is more dense than lead and thus more poisonous but less poisonous than osmium. Under certain conditions uranium can be (or become) very brittle and break apart into a fine dust that can be respirated.
I think there’s a little more to heavy metal toxicity than that...
> Toxic metals sometimes imitate the action of an essential element in the body, interfering with the metabolic process resulting in illness. Many metals, particularly heavy metals are toxic
Metal toxicity is the correlation between density and reactivity.
Iron and manganese are limited exceptions where iron is about 84% of hemoglobin, which is about 80% of red blood cells, but its toxic (though in larger doses) matches almost exactly the implications of other metal toxicity.
No, it doesn't. Your quote truncates a sentence that supports GP's point.
First sentence of third paragraph in linked wiki page.
> Although the gold ion is toxic, the acceptance of metallic gold as a food additive is due to its relative chemical inertness, and resistance to being corroded or transformed into soluble salts (gold compounds) by any known chemical process which would be encountered in the human body.
This is true of known natural metabolic processes, but not true with connection to certain drug interactions. Gold is not chemically inert and can be converted into an ion or gold salt, even within the body, when mixed with other reactive non-toxic chemicals. Gold metal is popularly consumed in trace amounts of certain alcoholic beverages and there are many medications that should not be taken in connection with alcohol for many different metabolic altering processes. I am not sure if it has been thoroughly tested, but a combination of gold and nangarin could also result in potentially toxic consequences, which is why certain fruits are forbidden with consumption of certain other chemicals/drugs.
This is exceedingly rare though, since platinum group metals are so expensive, but the same conditions are observed with other platinum group metals. Silver is more toxic than gold because it is more reactive, but the behaviors are similar. A major symptom of advanced toxicity from platinum group metals is a changing of skin color towards the metallic color of the metal toxin.
Gold has a far lower ionization energy than you are giving it credit for, which means it is capable of becoming toxic with relatively minor interactions. The safe for consumption statement implies interactions natural to human physiology are not likely to make gold toxic, but that doesn't account for other things humans consume that do trigger reactions not normal to human physiology.
Like gold we generally believe fruit juice is safe for consumption. Fruit juice is even classified as safe for consumption, like gold, by the FDA. This was proven to be not completely true when the price of grapefruit production fell in the 1980s. Certain chemical interactions with fruit juice will make you sick and in extreme cases will kill you. This phenomenon was only discovered because of numerous associated deaths.
Glad they didn't use plutonium, which is toxic!
"Official Iraqi government statistics show that, prior to the outbreak of the First Gulf War in 1991, the rate of cancer cases in Iraq was 40 out of 100,000 people. By 1995, it had increased to 800 out of 100,000 people, and, by 2005, it had doubled to at least 1,600 out of 100,000 people. ..."My colleagues and I have all noticed an increase in Fallujah of congenital malformations, sterility, and infertility," he said. ... the Fallujah health crisis represented "the highest rate of genetic damage in any population ever studied". ... Doctors in Fallujah are continuing to witness the aforementioned steep rise in severe congenital birth defects, including children being born with two heads, children born with only one eye, multiple tumours, disfiguring facial and body deformities, and complex nervous system problems. Today in Fallujah,...many families are too scared to have children..."
The "safety professional" was out of his depth and clearly undereducated about the risks of radiation and uranium ore in particular.
Hence, the true risk of a "dirty bomb" -- is psychological, i.e. it would be a weapon of mass disruption (not destruction), triaging a "worried well" would be expensive and time consuming.
I imagine there are some radiation-sources which are harmless outside the body because the dead cells of your skin would easily absorb and block them, but would wreak havoc if they were ingested or inhaled as dust.
Sometimes this is presented as a question where you have three or four cookies, which emit things like alpha/beta/gamma radiation and possibly neutrons, and you have to decide which cookie to eat, which to put into your pocket, which to put in a lead box, etc.
Where did it come from?
Why was it stored where it was stored?
Why did employees just dump the material?
Lots of people from all over drove out to the southwest with bucket and shovels, and tried to find this stuff in a (probably misguided) attempt to "strike it rich".
I'm sure more than a few just left their buckets of dirt sitting around Flagstaff and GCNP area - and they were found and moved around - and...
...here we are.
May or may not be true in this case - but I'm sure it has happened (and I am certain more buckets wait to be found).
No regulations, and no alarmist theories of risk.
Not saying it shouldn't be regulated, just that the regulations are inordinately strict and out of line with the evidence.
The problem is that radiation effects at low doses are very difficulty to detect. They could be very bad per unit of radiation and we could not now rule that out.
This is Lawyer Science, not actual science.
Priming DNA repair pathways acts as a protection from further exposures.
However, and this is my take -- there are people in the population that are more sensitive to the sun. These same people are probably more sensitive to ionizing radiation, LNT protects all, including the most sensitive. That being said, it's taken to an extreme, and allows for sensationalism and fear mongering.
And not court of law, by evidence and observation, i.e. science.
However, iff you developed a radiation induced cancer there's very little way to determine if your (mulitple) DNA errors were induced by cosmic rays or that time you walked past a bucket of naturally occurring radiation or due to those flights you took from Colorado to Brazil.
The dose makes the poison, we protect (and waste inordinate amounts of time and money) against low levels -- because we're ignorant to the precise pathways of cancer induction.
The notion seems to be the alternative to LNT is "radiation is not as bad at low doses as LNT". But there are many alternatives, all consistent with the evidence, and some would have the effect at low doses be worse.
Radiation is not a criminal defendant that requires proof beyond reasonable doubt to be regulated.