No you are misrepresenting what I said. My original point is exactly that there is a risk even from very small doses. I was attacked merely for pointing this out.

I never said that the risk in unacceptable, but merely stated that the risk has to be weighted against its potential benefits.

No comment.

Then your argument makes even less sense.

In other replies in this thread I pointed out the basic argument why most scientists believe that even very low doses of radiation cause a small risk of cancer and also gave a link to recent review which summarized the discussion and a study which shows an effect for patients which had CT scans. Giving you the right pointers to learn the facts is all I can do. Discussing this further is a waste of time.

I see your point, but I do not agree to the idea that society, by tolerating fatalities from traffic accidents, has accepted a universal trade-off between risk of death and cost. (There are many problems with this idea: how would you quantify the total value of mobility? Also society is not one single entity but consits of many different people with different interests. Cost and risks are also not equally distributed, e.g.. why should society trade a cost to GM with a risk of death to others?). But this is also irrelevant to the original question: The natural background radiation is nothing society has voluntarily accepted.

You are equating "very low risk" with "safe". This is OK in personal life but not if you talking about a large number of affected people. If something causes an additional very low statisitical risk of death to a high enough number of people, then some of them will die because of this. And this needs to be considered. That there are other risks which are higher is irrelevant and no justification to simply ignore this.

And yes, nuclear proliferation is also a concern, although I do not really understand why you brought that up here.

The overall harm society accepts for mobility is unrelated to the question whether a couple of lifes are worth the cost of an improved ignitation key.

Pearce et al., Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study, The Lancet 2012;380:499-505

First sentence of the discussion section: "In this retrospective cohort study, we show significant associations between the estimated radiation doses provided by CT scans to red bone marrow and brain and subsequent incidence of leukaemia and brain tumours."

Here is a relative new review: http://dx.doi.org/10.1259/bjr/...

No, you didn't get it. I will try with a car analogy: There are about 30000 fatal accidents with motor cycles per year in the US. This does not mean that the harm (16 deaths total or so) from GM's ignition key issue was overstated. The harm was huge relative to the minor cost savings. The other deaths are simply irrelevant to this consideration.

I have no opinion about the threshold, but there are two things to correct in your post:

He is absolutely right though. It is the common view of the scientific community that no amount of ionizing radiation is safe. This is also the basis of all radiation protection regulation everywhere (ALARA principle). The reason is simple: Ionizing radiation creates DNA damage with a small probability which then causes cancer with a small probability (which has then a certain probability of killing you). So even a single particle has a very small probability of causing cancer. There is a minority of people that believe that there are other effects (e.g. radiation at low doses activates the immune system) which dominate at low doses, but this is a minority view point and the data we have does not support this. From atomic bomb survivors see a linear correspondence between dose and risk down to about 50 mSv. For example, from this it was predictated that CT scans cause cancer with a very low probability and this has recently been confirmed.

This is a fallacy. The threshold should be set on the estimated benefits of a higher threshold vs the estimated harm from the additional radiation. The background radiation has nothing to with it.

Good point. This is an effect which can happen in certain circumstances. But Germany grew its economy with stable energy consumption for decades. So obviously this did not happen in the past. It also depends on energy policy, so it can be actively avoided.

That seems to be a common idea here in the US. Do you have some actual numbers?

Comment is mine. Forgot to log in.

An electricity generating company investing in renewables might have a competitive advantage relative to its competitor. Ofcourse, if both invest in renewables there is no relative advantage anymore. But this does not mean that the tax had no effect in this case - quite the opposite!

Energy use in highly-developed countries such as Germany or United States has been more or less stable for the last decades with a slight downwards trend. This is expected to continue.