The Numbers:20,000 asthma cases, 5,000 premature deaths.....

The Numbers:20,000 asthma cases, 5,000 premature deaths.....

PostBy: Richard S. On: Mon Jan 09, 2012 5:01 am

We've all heard these types of numbers before usually in environmental studies and other covering hazardous materials, ever wonder how they arrive at them? Obviously hard data for such figures is unattainable and I will note the following method isn't used for all of them.


http://www.epa.gov/risk_assessment/dose-response.htm
Linear dose-response assessment

If the "mode of action" information (discussed above) suggests that the toxicity does not have a threshold, then this type of assessment is referred to by the Agency as a "linear" dose-response assessment. In the case of carcinogens, if "mode of action" information is insufficient, then linear extrapolation is typically used as the default approach for dose-response assessment (for more detailed information, please see EPA’s Guidelines for Carcinogen Risk Assessment). In this type of assessment, there is theoretically no level of exposure for such a chemical that does not pose a small, but finite, probability of generating a carcinogenic response.



So how does this mumbo jumbo work? Suppose we have a 20 foot ladder that ten people have fallen off and five of them die. From this it is determined that for every 200 feet a population is to fall 5 will die.

For example if the population was 1000 people and each of them were to fall off a ladder a little over 2 inches the prediction is 5 of them will die from this fall.
Richard S.
 
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Re: The Numbers:20,000 asthma cases, 5,000 premature deaths.....

PostBy: coalnewbie On: Tue Jan 10, 2012 1:34 pm

I am not yet qualified to give opinions on coal stoves but epidemiology used to be my thing. Everybody above 5th grade maths knows you need four points to determine a straight line but apparently the EPA knows better and is allowed to presume a linear response when it may not be. Now we are supposed to believe that F U && kushima has already killed 14,000 of us. You have to look into the power of the study (statisticians please stand up). The FDA demands it in clinical studies when approving a new drug but the EPA can invent it and ecolunies believe it. Scour asthmatic journals (peer reviewed only please) and note that the increase in asthma in NYC is due in major part to HO or that fraction of the oil. It is rare to find hard data in epidemiology. Indian point blows up an 20,000,000 die from cancer that is a hard end point but it is rare to find it. To presume the shape of the dose response curve is next to impossible. Then we get into combination toxicology ----. Skin bruises on Gulf residents are almost certainly benzene (or other aromatics) poisoning, funny I don't hear a thing about that one despite the sample being big enough. Go ask a native.

This science will move forward when F**k**kushima blows up soon. Then we will have hard data to support that radiation does all sorts of nasty things, Of course we knew that too in the seventies when I was studying, there is very little new. Also of course, all we know now is that reactor 4 it has safely gone into cold shutdown. We are going to be sooo happy we blended in our waste nuclear weapons into that soup - but I digress.
coalnewbie
 
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