Point taken Goldielocks. I will look into it further. No one especially me likes to have there premise challenged but thats how we learn new things isnt it and it certainly is more stimulating than an echo chamber. I am learning alot at the moment about nuclear waste that is harmful to humans and things that are just radioactive which is not the same otherwise look out for Brazil nuts and Bannanas. I am also learning the difference between alpha and beta radiation emitters. Beta looks like the really bad guy so far. I wont be commenting on such a devisive issue in future. Also no one should follow my investment opinions. I have made some good choices but also some real stinkers too.
All radiation adds to your annual dose, but you would have to eat an awful lot of bananas for it to affect you (you could not eat that many). It is not simply a function of alpha, beta and gamma radiation but neutron flux, energy levels (which determines how deeply particles can penetrate your body) and half-life. While care needs to be taken with radioactive substances, the public (and green) perception tends to be unrealistic because of media misunderstanding or sensationalism or outright fabrication. For example, uranium oxide (yellowcake) is only mildly radioactive (I have sat on 50 gallon drums of it), mineral specimens perhaps just a little more so (because they contain isotopes other than just uranium that get separated out and left behind in yellowcake production. Ditto with uranium metal. The radiation level one metre from a drum of freshly-processed uranium oxide is about half the radiation experienced from cosmic (solar) rays on a commercial jet flight. Even a pair of disposable latex gloves gives almost complete protection when handling it. Keeping a 1-inch square piece of uranium metal in continuous contact with bare skin “increases the risk of skin cancer by 0.1 to 0.5 percent per year”. Smoking cigarettes is far worse.
Where dangers exist is in underground mining or mill processing of uranium ores to make the yellowcake, because radioactive radon gas is released from the ore and you can inhale it - it occurs in places like mineral springs baths as well (e.g. in central Victoria), so they must be kept ventilated - the spring water that you drink also contains radioactive radium (what killed Madame Curie) but at non-dangerous levels..
The real dangers of radiation are when uranium is refined to jseparate the uranium isotope U235 from the much more abundant U238. U235 is a stronger neutron emitter than U238. In a bomb or nuclear reactor, heat or an explosion is produced by getting a large mass of it (or artificially-produced plutonium) together in one place (eg one lump. or a number of fuel rods next to each other). Early bombs used to fire pellets of uranium to fuse as one lump in the centre, so the bomb only became dangerous then (exploded) and could be safely handled before. Here the radiation you are dealing with is neutron flux, and too much can cook you or kill you short or long term (in the case of a bomb so much energy is released in this form it can vaporize you). The uranium fuel in a reactor converts to other isotopes, some dangerous, as it emits neutrons, and the neutrons convert materials they hit into other new and often dangerous materials. This spent fuel is what is normally referred to as high-level waste. So the neutron flux creates new and dangerous isotopes from the enclosing reactor material (e.g. iron) and this is an issue when decommissioning a reactor (both low and high-level waste).
Half-life is the time it takes for half of any type of radioactive isotope to decay, and fortunately some nasty isotopes like iodine and caesium decay within days or months - but plutonium, common in high-level waste, takes 22,000 years. A lot of this goes into the air during a reactor meltdown like Chernobyl, but if you give non-radioactive iodine tablets to people immediately, they cannot take up radioactive iodine in the air, and that soon decays. Russia did not want to admit to a meltdown, so did not distribute tablets, and it had many cases of thyroid cancer (fortunately 92% treatable). With radioactive caesium in the days of atmospheric nuclear tests in the 1950s they used to get us kids not to drink milk for a while until radioactive caesium in the atmosphere had mostly decayed (it behaves chemically like calcium in milk - and gets laid down in growing bones).
So what is most dangerous? Reactor meltdowns, spent fuel (high-level waste) and components that have been irradiated in a nuclear reactor for years (high and low-level waste), working in a badly-ventillated underground mine or mill (crushing and grinding plant) - and having a bomb dropped on you.