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Wed 14 Mar, 2007 02:44 pm
Without having done any statistical analyses on the subject, Ive just been informed through the town florist today (we attended a funeral of a farmer near us) That of the 48 homes in the immediate area of about 4 square miles, 25 diferent homes have had residents whove either gotten or died from cancer. (The florist is an ideal source of such data in a small town as ours) . This, to me, constitutes a Cancer cluster. I want to investigate this on my own and Im not in my element , but Im considering the following aspects
1 Map the names and locations of the cancers on a topographic map. This seems a reasonable starting point
2See whether theres an even greater area of cancer occurences
3note dates of onsets and types of cancers
4Look at possible environmental conditions (eg radon flux of the area, agricultural history (we had truck farms until the 70's and truck farmers always used Lead Arsenate)
5Any other suggestions?
Im thinking of doing some Variogram analyses and or trend surface analyses after I get a better handle on the available data.
Whatever the cause, this is a waay too high incidence for cancer in a rural area. Its got me concerned and there may be certain environmental factors or personal common factors that link these.
2
Over what period of time?
Wow.
You know this, but probably a good idea to verify it before you do anything else. (This guy died of cancer, but did 25 other people?) Should be a matter of public record.
good point. I have only the information from the florist at this point but, according to her, all the people she rattled off were
1 citizens of this area
2all died of cancer in her tenure (about 15 years)
I agree you need to verify the data, find out over what period of time, and also what the actual number of the population within the homes is (ie what percentage of the total population that you are considering is....a large number of instances per house may boil down to a perfectly normal percentage of the population), the age range of the population, as well as find out the types of cancer.
A LOT of people die from cancer (second after cardiovascular disease, if I recall correctly?) so, over time, it is very normal for many households to lose members to it.
farmerman wrote:good point. I have only the information from the florist at this point but, according to her, all the people she rattled off were
1 citizens of this area
2all died of cancer in her tenure (about 15 years)
Fifteen years could well mean, to me, off the top of my head, that you may very well be looking at a pretty normal distribution of cancers...especially if it is an older population.
I have known of a few instances, now, when people thought they were in a cluster, but simple stats said they weren't. One of them sure as hell worried me when it was being investigated, because I worked in the same area as many of the folk who had died.
You should check to see if the data is already available. I know my area is available on the web. One study in my area focused on a large cluster of local people contracting stomach and pancreatic cancer. At least part of the reason was traced to the fact that this particular population had many hunters and they smoked and preserved their meats using nitrates, not to mention all the boloney sandwiches they ate while waiting for the deer to walk by.
Im beginning to do search and then a normative distribution by age and length of residence. We do live in an area of high radon, but Imm reserving the probables fo after the population.
Deb, the population stats that I know about just span all ages and the principle cancers are brain and lung , along with a group of leukemias. Id agree that this could be a normal distribution because "everybody's gotta die of something" but were talking about kids, young moms, dads, as well as middle aged and some olders.
I want to see first the 3-d distribution by locale and length of residence first.
I want to benefit from how all you in the health professions go about doing your pop stats
why not move and do the research from somewhere else? that's creepy.
When we did some major addition works on our ancient house, I had designed and installed a retrofitted radon removal system which involved doing some slant drilling and getting evac tubes under the house basement and the new additions (Those we could install the evac system within the stone bed under the basement slabs. In the area we have had radon reported as high as 22000 picocuries (the US health standard is 4).
Im somewhat jumping to a conclusion that I cant support and I dont want to conclude that its a radon problem unless I can eliminate evrything else.
I don't know if it's creepy or not.
Years ago there was a very convincing article or set of articles about a cancer cluster where people lived near some hypothetically dangerous wires - I forget the terminology; this was written up by Paul Brodeur. I believe it was eventually disproven as other than a random blip, part of regular cancer distribution. I had been very convinced when I read those articles, and later, when I read the knockdown, was convinced the other way.
Might be useful, farmer, if I or you can find links to that, both for the Brodeur articles, and the what-was-wrong-about-that articles. I think Brodeur's were in the New Yorker, back in 19XX.
sorry osso, Im in full investigative mode, its too late when I get like this. Ill report in when I have some data but the problem with some environmental causes are stronger than others. eg Arsenic (used as an ag chem) IS a known carcinogen, but its specific. Radon IS a carcinogen so is benzene and some other chemicals. However, lifestyles, diets, and age have some of the highest correlations as far as I can see.
25 deaths over 15 years is about 1.6 deaths a year.
48 homes with an average of let's say 3.5 people each....168 people.
That's just shy of 1% a year.
In 2001 553,400 people died of cancer in the U.S., let's say the population at the time was 275,000,000
That's .2%
hmmmm.....
I didn't mean to stop, farmer - just that what people found wrong with his work could be helpful. I'm all for what you're doing...
Central Idaho has higher than normal cancer rates, without a doubt. Our community has had three multiple myeloma deaths in the past five years. Supposedly, the rate for this type of tumor nationawide is 1 per 100,000. Considering our county population of 8,000, this certainly seems high to me. We have a group of people known as the Snake River Alliance seeking damages from the government because they believe that high cancer rates are attributable to nuclear testing in Nevada in the 1960's. I don't buy it. Our valley ranges in altitude from 3500 to 11000 feet, so we get more exposure to varied types of atmospheric radiation that most places. Indeed, there is a very strong anedcotal correlation between skin tumors and residential altitude. We also have widespread thorium deposits throughout the area, and radon is commonly found in high concentrations. Finally, the area was settled by a relatively small number of families, so the gene pool historically has been limited. In short, there are usually multiple reasons for statistical anomalies, and a single answer is rare indeed. Good luck, farmerman!
yep multiple hypotheses before jumping to any conclusions. Cowdoc , or Chai, where did you get your cancer stats?
Here's a link that refs what I was talking about - I didn't check the link it cites to all the articles saying what was wrong with Brodeur's work.
http://www.physics.umd.edu/lecdem/honr228q/specialtopics/health.htm
You seem to know what you're doing, Farmer - I thought what was considered no-no re statistics and inferences on clusters and cancers might be helpful.
Thanks osso, Ill read that as soon as Im done posting.
Iwas gonna say that , (based on the thorium thing that cowdoc mentioned) Radon is also an alpha emitter and as such, the USPHS and the NRC had issued health guidelines re: cancer risks . The highest incidences of specific types of cancers in the "radon Belts" are lung and matastisized to brain, then pancreatic and certain leukemias.
The highest radon zones in the US are reportedly in Iowa, Idaho, and Pa's "Reading Prong" (if bi-bear is listening in the Reading Prong has to do with geology not what your thinking). The whole radon issue came to light in PA when a guy who worked at the Limerick nuke Station was recording a higher rad dose on his film badge when he was at home than from work (They would record the film badges when the workers entered and left the plant ) and hed leave with a clean badge and the next morning it would be exposed. So they discovered the Uranium deposists in his backyard near Pottstown Pa.
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