Re: LNT, Collective Dose

[Ted de Castro <tdc@xrayted.com>]

Harry Hinks wrote:
> 
> Mr. DeCastro,
> 
> I may be mistaken, but I think you are mixing up LNT and collective dose
> assumptions.

In a linear risk situation its the same thing!  That is PRECISELY the
point that many are trying to make here - the summing of person
microREMs into populational REMs and then declaring cancer deaths!

> 
> In studies where you collect data at each house, you do not have to make
> either LNT or the collective dose assumptions.  Assume you go out to the
> nearest town and randomly choose 3 homes to test their radon in their
> basement.  Again assume you get readings at the 3 houses of 24
> pCuries/liter, 2 pCuries/liter and 1 pCuries/liter.  With summary data using
> the collective dose assumptions, you would assume the basement concentration
> for each individual in that town is 9 pCuries/liter, correct?  But in
> reality, you know the basements were 24, 2 and 1.   In studies using data
> from individual houses, you have the readings.  In summary data studies, you
> do a poor job of measuring the actual concentrations.
> 

Well I'll try once again.

If the risk is LINEAR it is proportional to dose.

If that risk is R then in house 1  the risk is 24R in 2 its 2R in 3 its
1R.

Risk for that population is then the sum of the individual risks

= 24R+2R+1R = 27R

For LNT the average exposure is as you say 9 - thus the average risk is
9R thus the total risk for the population of 3 is 27R!!!

With LNT the prediction is NOT WHO - BUT HOW MANY!

This is precisely what LINEAR means.

I think this is what Jim means to by "missing the point".  I'm not
saying this in a mean way or suggesting any purposeful intent.

Its is simple math - its is the definition of a linear co-efficient.

IF this doesn't work - then it is NOT linear!

I'm not disagreeing with how you suggest the risk should be apportioned
- I infact do agree - I agree it isn't linear!

All you arguments are predicated on a supposition that it is NOT linear.

I don't know your math or statistics background so I cannot comment
further - but there is nothing magical or mysterious about it.

THINK about it for a minute.
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