Radioactivity in Tobacco | Hacker News Reader

Radioactivity in Tobacco

epa.gov

65 pointsahiknsr61 comments

> Tobacco farmers use fertilizer to help their crops grow. These fertilizers contain a naturally-occurring radionuclide, radium. Radium radioactively decays to release radon gas, which then rises from the soil around the plants. As the plant grows, the radon from fertilizer, along with naturally-occurring radon in surrounding soil and rocks, cling to the sticky hairs on the bottom of tobacco leaves, called trichomes. Radon later decays into the radioactive elements lead-210 and polonium-210. Rain does not wash them away. Polonium-210 is an alpha emitter and carries the most risk.

Isn't this true of every plant we cultivate and put into our bodies? Or is there something particular about tobacco trichromes and Radon? Or tobacco-specific fertilizers? Inhalation vs. ingestion? This is all coming on the heels of learning yesterday that everyone has like 20-60 lbs of lead in their back yard: https://news.ycombinator.com/item?id=23039020

Tobacco leaves have sticky hairs on their underside, which is what makes them different from other crops: it’s these hairs that absorb the radon and prevent it from being washed away with water. Also, the type of fertilizer used for Tobacco might be different than fertilizers used for other crops.

> sticky hairs

Reminds me. My ex-wifes grandmother said when she was a little girl her family packed up from tobacco country to California. And her utter joy when her mother told her that no they don't grow tobacco in California.

Because picking tobacco is gross and nasty work.

It is, and the US still allows child labour in tobacco farming.

https://www.hrw.org/video-photos/video/2014/05/13/made-usa-c...

https://www.hrw.org/report/2015/12/09/teens-tobacco-fields/c...

https://www.hrw.org/report/2014/05/13/tobaccos-hidden-childr...

https://www.hrw.org/news/2016/05/10/dispatches-obama-bans-e-...

As a kid growing up in Scotland I worked picking daffodils in spring and berries in the summer - absolutely back-breaking work, but at least you got to eat your body weight in berries for free!

We were paid a pittance based on how much we picked. It wasn't only kids, and was never thought of as "child labour" at the time - I wonder if this is still a thing in the UK?

It probably isn't still a thing in the UK, because we now have things like national minimum wage and stronger protections against child labour.

No, many plants have these AFAIK. Tomato leaves are pretty sticky. Potatoes too IIRC. Happens that both of these are in the same family as tobacco though.

I just realised your point that tobacco is a leaf crop unlike spuds and toms, so ok, point taken.

Tobacco is a lot more sticky than most other crops, to the point that it has been hypothesised to be a semi-carnivorous plant. Insects actually get caught in them, it's just unknown of the plant actually actively digests them. That's also why harvesting tobacco is not very pleasant, with all the stuff stuck on their leaves.

Actually I've heard exactly the same - including the conclusion of vegetal carnivory - for tomatoes too.

Surprising number of links here: https://duckduckgo.com/html?q=tomatoes%20carnivorous%20stick...

If you pick on, this https://www.independent.co.uk/news/science/attack-of-the-kil...

Bean leaves also have sharp protrusions, I understand. Probably for defense against insects more than carnivory. Freshly picked bean leaves placed on the floor are supposed to be a defense against bedbugs.

> is there something particular about tobacco trichomes?

Absolutely nothing

Well... Either this people are genius that discovered a way to suck and harvest expensive argon and helium from the air, with the help of super-sticking tomato that traps them magically in a everest size (from the point of view of a radon atom) trichome.

... or maybe the history is false and noble gases still keep their reputation of not interacting with anything and being difficult to trap.

I would put my money in the second possibility. It looks exactly like the kind of convoluted history that tobacco makers would create to avoid paying compensations to the families of people affected by cancer ("Tobacco is safe, healthy for children and medicinal, manure makers dose our nice flowers with radiation and are the real responsible, so should share the bills").

I wouldn't rush to seed Tobacco in Fukushima.

This is very nearly useless because it doesn't give the range of dose rates they see in tobacco (am I missing them!?). Low radiation doses are normal and natural and have been part of life forever. High doses from concentrated stuff can cause trouble. So what range are we dealing with here!?

When you have detectors capable of seeing a single atom decaying, quantitative dose rates are always required to have a meaningful and useful conversation.

Incorrect. There is no such thing as safe dose with Radon. You're thinking of gamma rays and 50mSv/year safe limit. You won't find safe limit for Radon. There are guidelines when you should be very concerned, but there is no safe limit.

It decays into radioactive lead, and once we breath it in, it's hard to get rid of, and stays in our bodies.

I have a hard time making sense of this. Would it mean 1 atom of Rn is always fatal for any individual? The fact that it accumulates in the body doesn't mean it is fatal at any dose.

No, of course not, but Radon is highly radioactive and extremely small amounts are enough to measurably elevate your risk of cancer. We’re talking numbers like a few million molecules in a room.

We need to be more specific: Radon is a gas that goes through alpha decay. It is this specific combination that makes it dangerous. The gaseous form enables easy ingestion by breathing and alpha particles are extremely damaging at short ranges - sub-mm in solid matter. The dead outer skin layer is normally able to perfectly absorb alpha particles which make most emitters effectively harmless. Ingested alpha emitters are different as the emitted alpha particle enters living cells immediately. At that point it is a game of chance whether something gets destroyed or altered that is important for cell reproduction. Also, ingested radioactive emitters are impossible to remove from the human body.

> Also, ingested radioactive emitters are impossible to remove from the human body.

I think that’s only true for things we don’t metabolize?

Right. I should have rather said that there are no medical treatments that can remove ingested radioactive emitters in any meaningful way.

Chelation has been used to remove ingested Am, Pu, and Cm. It takes a while, though.

.. but it's also pretty much unavoidable in some places, as it leaks out of the granite in the ground.

It's mapped, in UK, and a standard part of House buying checklists.

Eg https://www.ukradon.org/information/ukmaps .

The regulations use a linear no threshold limit to be safe. But it has not been proven that there is a linear no threshold dose response. So I am not incorrect.

The article is just an informative piece for the general public. Adding more details would clutter the text and add little to non experts. I think that it is a reasonable approach to highlight a risk situation were the clarity of the message is important.

If you want more data a Google search brings more detail:

https://www.researchgate.net/publication/24425555_Radioactiv...

Then they may have well just written "Smoking Bad".

If the motivation is to educate people on the dangers of smoking (which they already overestimate due to the fear based anti-smoking campaigns) they should probably tell us why.

The link you give links to http://dx.doi.org/10.3390/ijerph6020558

"Radioactivity of Tobacco Leaves and Radiation Dose Induced from Smoking"

The gist:

> In estimating the radiation dose induced from smoking, it was concluded that the annual effective dose to lungs due to inhalation for adults (smokers) averaged to 80 μSv for 226Ra, 67 μSv for 228Ra and 105 μSv for 210Pb, that is 252 μSv in total. The annual effective dose due to 137Cs of Chernobyl origin averaged to about 200 nSv, that is three orders of magnitude lower than that of the naturally occurring radionuclides. The effective dose of 252 μSv per year must be compared with the average worldwide exposure to natural radiation sources due to inhalation 1.26 mSv y−1.

(although the source for the radioactivity is not only fertilizer, but a combination of fertilizer, natural radioactivity, and to a tiny amount Chernobyl fallout. The plants were sampled all over Greece.)

Not all radionuclides are as dangerous as others. As an extreme example the body keeps the level of potassium constant in the body rendering naturally radioactive potassium completely harmless.

Every year 8 million people die because of tobacco. In the US alone, the number of deaths (due to tobacco) per year is close to half a million. Similarly between 4-7 million people die due to air pollution. Ironically, that does not alarm anyone, that does not cause lockdowns, that does not require flattening the curve. The numbers don't lie - global lockdowns that led to significant drop in air pollution may have coincidentally saved more lives and helped mother nature heal.

That’s because no one has found a way to make billions of dollars out of Coronavirus yet

Smoking is a choice.

Secondhand (passive) smoking often isn't. :(

Conflating tobacco induced deaths with covid19 deaths is, for one, a giant big mental shortcut. Then throwing lockdowns in it. And finally ending of a 'mother nature is wounded' note. This is not Reddit guys.

Is radium only present in tobacco fertilizers? What separates tobacco fertilizers from other plant fertilizers? Am I at risk for eating tomatoes grown with normal off-the-shelf fertilizer?

Well, don’t eat the tomato leaves for one. If you compare the mass of undried tobacco leaves to a similar amount of food, I would guess similar exposures. I would also guess that the fruit contains more water, therefore a slightly less concentration of radiation.

It’s also about the system, lungs vs digestion. Digestion has been dealing with natural radiation for longer than we have been smoking.

Good question!

I also want to point out things like strawberries are irradiated on purpose to extend shelf life, not the same thing as radionuclides in the food, but a nice example of radiation protecting the food supply and preventing quick spoilage.

Edit: I think all fertilizers are the same, mostly from petrochemical stock. Nothing separating tobacco and food fertilizer.

Most food is irradiated, yes. Prevents potatoes from sprouting, sterilizes tons of food, etc. I am very familiar with that, but didn't realize that radionuclides were ever-present in fertilizers.

I grow my own tea, and use fertilizer. Am I at risk for the same issues after processing the leaves? Additionally, would this then extend to cannabis as well? While they aren't leaves, I'm assuming that radium would end up there as well if in the fertilizer.

I guess what I'm trying to say is what is it specifically about tobacco - is it the mechanism of intake of the tobacco plant specifically, is it a property of all plants and fertilizer, or is it only a property of specific parts of all plants?

To your last question--as a severely amateur player in this one: tomato and tobacco are both nightshades so I imagine the growth of the leafing parts are similar in action.

Hopefully someone else will either correct me or elaborate.

> Most food is irradiated, yes.

No, far from it. Extremely little food is irradiated.

"103,000 tonnes of food products were irradiated on mainland United States in 2010"

"6,876 tonnes of food products were irradiated in European Union countries in 2013"

The average American consumes a tonne of food per year, and the average European probably isn't much different. That's 0.03% of food in the USA, and less than 0.001% respectively.

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

I wish they made that more clear as well. They do say that these things get stuck on the leaves. Most vegetables get washed at some point before you eat them.

Radium is also present in Brazil Nuts. Some plants aggregate chemical elements more than others.

We use them to linearize the energy scale in lower-background germanium detectors. Grocery-store potassium chloride sets our energy calibration.

The bad thing about radium in tobacco, I am told, is that the alpha-emitting radium (or the daughters) tends to aggregate in the lungs. Alphas do a lot of nearby damage, hence a mechanism for lung cancer.

I still eat Brazil nuts without a second thought, even though I've measured the gammas...

Alpha is the worst internally (than gamma or beta) because it's a big particle (2 protons, 2 neutrons) and does lots of damage internally but can't pass through skin or clothes, so externally it's less dangerous. Additionally, the alpha particle can cause minerals in the body to become radioactive, thus extending the danger.

Brazil nuts are known for being particularly high in selenium.

> Grocery-store potassium chloride sets our energy calibration.

I'm guessing this gives a new meaning for the phrase "banana for scale"

Could be, though the KCl is a better standard. We know how much KCl we have, and the natural abundance of K40 is well-known.

You'd need a dedicated campaign to assess the potassium abundance in the "standard" banana before you could use it at better than ~100+% errorbars.

The salt-substitute shaker is probably a <5% standard, and we've been using the same one for years.... :).

Tobacco is radioactive because the radioactive particles stick to the trichromes. Tomatoes don’t have trichromes, so no, unless you’re eating the leaves.

Would cannabis treated with fertilizer have the same effects then?

It would have radioactive particles stick to it, if that’s what you’re asking.

Just hypothesizing, but there might be a difference between the accumulation of materials in the lungs vs gastrointestinal system.

This is specific to tobacco: firstly that the tobacco leaves pick up trace amounts of polonium-210, and secondly that inhaling tobacco smoke concentrates the Po-210 into localised deposits within the lung. Because Po-210 is a short range alpha emitter, these deposits deliver a significant radiation dose to small areas of lung epithelium. This dose is believed to contribute to the carcinogenic effect of tobacco smoke.

Eating vegetables does not lead to tissue irradiation in this manner. You are not at risk from eating tomatoes (or other fruit and veg) whether or not they are fertilized with rock phosphate.

Hate to be that person but... does the cannabis plant have similar properties?

I believe it would since cannabis also has sticky trichromes on its bud and surrounding leaves.

"Toxic chemicals in tobacco smoke are the main reason cigarettes cause cancer, but radiation also may play a part." That's the best that EPA can do here? Is there really no data?

No one has conclusively shown that radiation causes or does not cause cancer at low doses, on the order of the world's variation of the natural background radiation dose. There are lots of data. It is noisy.

It may even be healthy[1]. It stands to reason that organisms that evolved in a radioactive environment would have some physiological ability to compensate and that it would follow the general adaptation pattern. Mithridatism is very real after all.

[1] https://en.m.wikipedia.org/wiki/Radiation_hormesis

Or, it may be even more dangerous at low doses than LNT implies. The data are too noisy to tell.

Also polonium. https://www.cdc.gov/nceh/radiation/smoking.htm

Bananas are radioactive too, due to their potassium content. Nobody worries much about those.

Radioactivity derived from tobacco is significantly higher than from bananas.

There is a very nice episode of Veritasium (science divulgation YouTube channel) which shows exactly this together with other "well known" radioactive sources (e.g. Chernobyl, Fukushima, Marie Curie's office etc)

Potassium cycles through the body quickly.

Radioactivity in Meth. The devices and instrument used in the production of Meth have been seen to contain a lot of unclean particles and may be the cause for users to get sick

Has this been measured in tobacco-based vape liquid?

Is this applicable to vape salts as well?

I'm guessing they're mostly synthetic so, probably not.

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