# Po-210 in cigarettes, is it dangerous?

1. Oct 15, 2008

### DeShark

Hi all, I'm currently learning about nuclear physics at uni and we just covered Sieverts and dangerous levels of radioactive sources. I came across an article today that said cigarettes contain polonium 210 with an activity of 0.01 Bq/gram of tobacco. I therefore couldn't resist doing a calculation. But I became unstuck fairly fast. Basically, I want to work out the dose equivalent for smoking this stuff in Sierverts.

As I'm not a biologist, I don't know how many grams of this polonium are going to end up in a smoker's system, I couldn't really make anything like a good guess on the dosage in a year, but I decided to do some sort of calculation just to get a rough idea of how dangerous these cigarettes are. I just want to make sure I'm going about this the right way, cause we've been told that this sort of question will be on the exam. Think of it as real life revision.

So I made some assumptions. 1) The smoker doesn't smoke the cigarette, they place it in their mouth for 5 minutes, 20 times a week for a year. 2) The cigarette contains 2g of tabacco (http://wiki.answers.com/Q/How_many_gram_tobacco_is_in_one_cigarette) 3) The Polonium only emits alpha particles at an energy of 5300 KeV. (http://en.wikipedia.org/wiki/Image:Alpha1spec.png)

From this, I did the calculation:

$$5 \times 60s \times 0.01Bq/g \times 2g = 6 Emissions$$
$$6 \times 5.3\cdot10^6 eV \times 1.602 \cdot 10^{-19} J/eV \times 20 (Q factor) \times 1 (N factor) = 1.02 \cdot 10^{-10}Sv$$
$$1.02 \cdot 10^{-10}Sv \times 20 (times a week) \times 52 = 0.1 mSv$$

So if I'm right, just placing a cigarette in your mouth for 5 minutes 20 times a week increases your natural dosage of radiation (2.4 mSv) by 5%. Is this right? I dread to think what actually inhaling the stuff into your body might do. Anyone got any thoughts on this? Most importantly, is my calculation right?

P.S. Here's the article (in french) http://www.lefigaro.fr/sante/2008/0...t-du-polonium-dans-la-fumee-de-cigarette-.php

2. Oct 15, 2008

### Tom Dennen

Hi,

It's dangerous enough for the British Health Department to cancel parts of an ad campaign that warned against it. I've on the marketing side of this issue and have been collaborating with a Dr. Richard Hurt at the Mayo Clinic nicotine dependence center.

He's a better copywriter than I'll ever be, but he's closer to nicotine dependence than I am, so all credit where due - this is where we are at the moment:

"Cigarettes are the only product on the planet that when used by the consumer as promoted by the manufacturer kills 60% of the customers!

"Cigarette packs should carry a radiation-exposure warning label."
Richard D. Hurt, Nicotine Dependence Center, Mayo Clinic, Rochester, New York.

The problem is the power of the tobacco lobby - enough power to pull certain information from the public eye.

For more background (in a kind of sensationalistic way) google opednews.com tom dennen the multi trillion dollar serial killers for a start, and keep up the math!

Tom

3. Oct 15, 2008

### mgb_phys

It's more interesting for what it says about peoples attitude to radiation.
Warning labels that the cigs will kill you = no effect
Pictures of diseased lungs on packet = no effect
Ban on advertising = no effect
A radiation warning label = would scare enough people off smoking that the tobacco industry would fight against it.

4. Oct 15, 2008

### DeShark

A radiation warning label would stop me from stocking 500 cigarettes in my shop... if I had one.
However, it's just alpha radiation, so the paper packaging's enough to stop it... But are my calculations right anyone?

5. Oct 15, 2008

### mgb_phys

Probably pm astronuc for an expert on dose calculations but I wouldn't have though an unlit cig poses much of a hazard.
The alphas are mostly going to be asbsorbed in the cig anyway, those that do get out will only get in the cells of the walls of your mouth which get renewed fairly quickly. Smoking on the otherhand seems an ideal way of getting emitters lodged deep in your lungs.

ps. Po only has a half life of 100days or so, how long does it take to harvest tobacco, dry it, ship it, turn it in cigs and how long do they sit on shelves?

6. Oct 15, 2008

### HallsofIvy

Staff Emeritus
I'm puzzled by this. Because it is dangerous, the British Health Department stopped warning against it?

7. Oct 15, 2008

### mgb_phys

It's poor journalism/sensationalism, the UK pulled an ad about polonium in cigs due to the Russian spy being assinated in London with Po. http://news.bbc.co.uk/2/hi/health/6168887.stm

Supposedly this was to spare his family. But after he was poisoned in a restaurant there was a mad tabloid panic about anything to do with Polonium (or any sausage that sounded the same / or anything to do with poland) and so health posters mentioning Po weren't exactly popular in hospitals / bars etc.

Last edited: Oct 15, 2008
8. Oct 15, 2008

### DeShark

Haha, sounds ridiculous... I have a feeling the govts make too much money from tax on cigarettes to run a successful campaign to stop people smoking. My guess is the NHS is losing money because people smoke, but the govt are making money on taxes, so to make the most money, a happy equilibrium must be struck...

Basically, Alexander Litvinenko dying made the campaign more likely to succeed, overtipping the delicate maximisation function in the linear programming problem on how to make the most money and keep the populace voting for us.

9. Oct 15, 2008

### Tom Dennen

A little lapse in cigarette grammatical sin tax there; it would be dangerous to kill the goose that lays so much egg in tax revenue not to mention in the economics involved around the infrastructure - in the growing, reaping, curing, packaging, warehousing, marketing (big bucks here), distribution - a lot of employees here, too.

Thanks for picking ... that up.

10. Oct 15, 2008

### mgb_phys

In the UK the NHS spends £1.5bn a year treating people with smoking related diseases.
The government spends around £30m on anti-smoking education campaigns and £40m is spent helping people stop smoking.
It then spends £88M subsidising tobacco farmers.

On the other hand it receives around £12 billion per year in tax on cigs (2004 figures)

11. Oct 15, 2008

### Tom Dennen

That is awesome. Two hundred and eighty million is spent out of an income of one thousand two hundred million. I'm an American; is 10% of twelve billion a hundred and twenty million, about what is spent?

If so, what happens to the other 70-odd percent?

12. Oct 15, 2008

### mgb_phys

Profit !

13. Oct 16, 2008

### Tom Dennen

I knew that!

AND I'll pay off my IOUs using your IOUs!

(A Definition of financial meltdown) - I'm a student of economics, not a physicist, but interconnectivity seems to be gaining some credence among those who busy themselves connecting dots for fun and ... profit.

14. Oct 16, 2008

### Staff: Mentor

Have you accounted for the fact, that cigarette emits in all directions, while smoker occupies only a fraction of the solid angle?

Thing that I don't get is - why cigarettes are to be specifically more radioactive than - say - spinach. In both cases we deal just with leaves.

15. Oct 16, 2008

### Tom Dennen

That great American linebacker 'The Fridge' when asked his opinion of AstroTurf versus grass:

"Dunno. Ain't never smoked no AstroTurf."

16. Oct 16, 2008

### DeShark

No, in my calculations, the "smoker" literally just places tobacco straight into his/her mouth for 5 minutes, 20 times a week. I know it's a chronic model, but I don't know what percentage of the contents actually end up in the lungs and how long they stay there. I just wanted some method of giving myself a rough way of finding out roughly how radioactive the things are...

"Si le 210Po est présent dans la fumée, c'est à cause des engrais riches en phosphates que l'on utilise pour cultiver le tabac. Ils sont extraits de mines d'apatites, une roche qui contient du radium et du polonium."

Apparently, it's because of the fertiliser which is rich in phosphates that the guys use to grow the tabacco. It's extracted from apatite mines. Apatite is a rock containing Polonium and Radium. (I don't think they use the same stuff for spinach). I have a feeling lung cancer could be cut severely if they just sourced their fertilizer from something non-radioactive...

Last edited: Oct 16, 2008
17. Oct 16, 2008

### mgb_phys

If the cig is unlit then you only have a fairly narrow angle that actually aims back into your mouth, in addition the cig itself will absorb alphas so only the outer few mm will contribute any dose. Once you light it you can pretty much assume that all of the mass passes into your lungs.

I think you might have a fundemental misunderastanding about their attitude to their customers!

Last edited: Oct 16, 2008
18. Oct 16, 2008

### Staff: Mentor

All volatile mass to be exact, my bet is that most polonium will be left in ash.

19. Oct 16, 2008

### mgb_phys

Probably - but if you were looking at the worst case.

You have to picture the scene at the tobacco company;
"They let us sell this stuff - what else can we do"
"We could make it radioactive as well"
"Great idea, next we will try putting razor blades in the packets"

20. Oct 22, 2008

### Katrex

Ok I'm going to have a go((didnt you forget radiation factor and tisue factor?)) but ignoring that
2.4msv... ok so thats aproximatly 1/500 of a sv so thats 3%/500 chance of geting cancer say they smoke for 50 years
thats an extra 0.3% chance of getting cancer... Is it just me but you'd think if you'd smoked for 50 years if you were gonna die of cancer you would have done so allready. though that said over a population of say 300 milion who smoke 300000 ish((asuming most die before smoking for 50 years so i guesed at 0.1% chance)) people who will get cancer because of it, but hell whos counting?