I’ll give you a pointer later to a National Institutes of Health (USA) web page. This page is about polonium, tobacco, and (mostly lung) cancer.

First, some background on polonium and its dangers.

Polonium was the means used to kill Alexander Litvinenko. It was a case of spy payback. There is a fine Wikipedia article here on this.

Since you are all probably google competent, you can research polonium on your own. It is very radioactive; apparently a gram generates something ridiculous like 140 watts of power. It is weird, evaporating itself into the air well below its melting point. Its radiation cannot penetrate skin from outside, but it can itself be absorbed through skin. Its radiation is alpha particles – easily stopped by living tissue – and thus extremely dangerous if ingested or inhaled. Fatal doses are measured in micrograms.

Polonium was possibly involved in the death of Yasser Arafat. It was on his clothes and toothbrush. Apparently later testing ‘showed’ polonium was not the cause of Arafat’s death. I can be forgiven for stating this as I just did. I have a right to my opinion here.

That’s background so you understand that polonium is extremely dangerous in very small amounts. Now some stuff about polonium, the element, itself.

Virtually all polonium today is manufactured using cyclotrons and the like. Pretty much all of it is made in Russia, some 100 grams a year.

It can be purchased in the USA in a ‘needle source’ form, which is a needle coated with polonium is plated with gold and sealed. It’s used to demonstrate things like cloud chambers to particle physics students. Amounts used are tiny.

It is possible to refine polonium, for example from many tons of the waste left from radium extraction from ore, a few grams of polonium were extracted once – at great effort. It’s easier to make it, and you don’t need much.

Now for the relationship between polonium and tobacco.

Tobacco, to have good flavour, needs lots of fertilizer. The fertiliser used is captured from natural rocks. Those rocks contain other isotopes of lead and uranium which can spontaneously decay to produce polonium. The amounts produced are small, but they adhere to the tobacco leaves’ surfaces and are, to some extent, also taken up by the plants.

The polonium on tobacco plants tends to form an insoluble, very small-grained, solid on the leaves. It turns out that this is the most dangerous, and hardest to filter, form of polonium.

The tobacco companies knew all about this. They denied it extensively, wrote and suppressed reports, and were guided by lawyers and the need to maintain profits.

The NIH article on this can be found here. I will summarize a few key points with quotes (in italics) and my own thoughts (in plain text.)

The major tobacco manufacturers discovered that polonium was part of tobacco and tobacco smoke more than 40 years ago and attempted, but failed, to remove this radioactive substance from their products. Internal tobacco industry documents reveal that the companies suppressed publication of their own internal research to avoid heightening the public’s awareness of radioactivity in cigarettes.

It is estimated that smokers of 1.5 packs of cigarettes a day are exposed to as much radiation as they would receive from 300 chest X-rays a year.

 … the majority of the PO-210 in tobacco plants likely comes from high-phosphate fertilizers applied to the tobacco crop.

Former Philip Morris scientist Farone testified in 2002 that Philip Morris closed its low-level radioactivity facility because of product liability concerns.

I’m sure you get the idea. To summarize:

• Tobacco firms knew about polonium risks in cigarette smoke some forty years ago.
• The polonium comes from phosphate fertilizers that come from rocks that contain a small but significant amounts of radioactive precursors of polonium.
• The polonium ends up in the soil and on the plants as dust etc.
• Various research was done to mitigate this, including: washing the leaves, selecting out the most radioactive leaves, genetic modification to make washing easier or leaves smoother, and some inquiries into fertilizer sources. (The latter were deemed too difficult to control.)
• Particulate polonium is delivered, in tobacco smoke, directly to the cell surfaces, including the lungs.
• Nobody does 300 chest X-rays a year.
• In-house research indicating public numbers re polonium density were suppressed, even though the in-house numbers were significantly better, because the public seemed to have forgotten the issue and nobody wanted to ‘wake the sleeping giant.’
• Radiation detection equipment was taken down so as to increase deniability of the polonium cancer risk. This from testimony under oath.

OK, you say, now what’s your point? And what’s the dumb question?

The point: companies will risk their client population if that will increase or extend profits.

and

Smoking really is dangerous.

What will change? Will ‘This product is radioactive’ be added to cigarette package warnings? Will compensation for lung cancer deaths be easier to obtain? Will smokers quit or cut down?

Those are the dumb questions.