EMF was discussed and referenced well a few years ago in an the "Access to Energy" newsletter of Art Robinson accessible at www.OISM.org.
Radon studies do indeed follow the health effects, the selection distorting inference for application. Ruth falls into the usual trap when writing (below),"Radon - produces a known carcinogen (ionizing radiation)". THE DOSE MAKES THE POISON. (Bill Lipton please note). Muckerheide's website categorizes hundreds of studies suggesting that ionizing radiation, less than 10 cGy (rem) acute (more, slow rate), may PREVENT cancer. Allergy shots, sunshine, iodine, fluoride, cobalt, iodine, etc give examples of the principle.
"Radon prevents cancer", is as valid a statement as, "Radon causes cancer"!
The American Cancer Society should publicize both. Iowa counties are
in the upper 1% of USA home radon concentration, an outlier. Field's controls
had >4pCi/L (although his lung cancer cases had even higher home radon)
Selection of outlier Iowa is understandable, if you live in Iowa. Application
to the USA, where home radon mean is 1.3pCi/L, extrapolates beyond Field's
data. Indeed, Cohen's county lung cancer mortality rates were least about
3pCi/L, rising above (consistent with Iowa lung cancer cases having more
home radon than controls), but also rising even more where < 1.3 pCi/L
- most of the USA.
Selection and extrapolation to populations or persons not like the study can injure. Since every person is different, medicine is still an art.
Howard Long
RuthWeiner@AOL.COM wrote:
Apologies in advance for a long post, but my thoughts may be of interest to RADSAFERs.I am not an epidemiologist, but I am an observer. Thus, I have been thinking about what troubles me about the supposed magnetic field (Fritz is right -- we were all sloppy) impacts on leukemia, miscarriages, asthma, Type-II diabetes, etc.
I had my teeth cleaned with an ultrasound probe today. I don't get exposed to that magnetic field more than a half hour every three months, but the hygeinist is exposed every day for about 6 hours. Moreover, nowadays ultrasound pictures of fetuses are quite regularly taken. If a group were studying the putative impact of magnetic fields on miscarriage rates, dental hygeinists and pregnant women getting ultrasounded would seem to be logical study subjects. Why weren't they selected?
The whole approach in the magnetic field studies contains an insidious bias. The Field, et al, radon studies may contain a similar bias. A really simplistic summary of the way such studies are done is:
Step 1: an environmental phenomenon exists (magnetic fields from AC transmission lines, radon in homes, second hand smoke) that some people think might have some effect on health.
Step 2: the epidemiological investigator tries to determine what the health effect might be, and selects effects that are suspected to be correlated with some environmental insult, and/or that have been correlated with sizable exposure to some environmental insult. Cancer is everyone's favorite because some cancers meet one or the other criterion. Allergies and chronic disease meet the first criterion. Since the Alsea, OR case was refuted, the only reason I can see for looking at spontaneous miscarriage is that it is lurid.
Step 3: The investigator designs a case-control study in which his or her cases are the people who have suffered the insult (cancer, miscarriage).
Step 4: The exposure to the environmental insult is measured.
Final step: The investigator "bins" the exposure data, claims to have accounted for all confounders, shows some kind of association between the exposure bins and the cases, and claims correlation.
Snip
Snip
The epidemiology of second-hand smoke has considerably firmer bases than the epidemiology of either magnetic fields or radon in the home. The latter two have only shown weak correlations with health effects. Radon, at least, produces a known carcinogen (ionizing radiation), so the question of correlation is more
Just because you don't like something, or it messes up the natural environment, doesn't mean that it can be correlated with health damage, or even that there is enough justification to go looking for health damage.
Ruth Weiner, Ph. D.
ruthweiner@aol.com