How to Seek and Not Find
March 31st, 2006
Dan Olmsted, UPI’s Senior Editor for autism-mercury conspiracy, has gone on record (twice) saying that autism is only seen in vaccinated Amish children. He even performed an “exhaustive” search of the Lancaster County Amish communities looking for autistic children. His failure to find any (other than children who had been vaccinated) is further evidence - he claims - that vaccination and, more to the point, the thimerosal in vaccines is responsible for causing autism.
This rather simplistic view of sociology, neurodevelopment and genetics has been heralded, nay, brayed to the world as “proof” that mercury causes autism. Now we are presented with another possible explanation of Mr. Olmsted’s amazing findings.
In the 30 March 2006 edition of The New England Journal of Medicine (not up the “standards” of Medical Hypotheses, to be sure, but a solid journal nonetheless), a group of researchers from the Clinic for Special Children in Strasburg, Pennsylvania (which provides services to a large number of Amish and Mennonite children) report a genetic mutation which causes:
“…seizures that progress to autism and retardation” (see here for a nice review of the article)
This mutation is seen in much more often in Amish and Mennonite children, primarily because of their very small gene pool (see here and here for a review). This is not the only genetic disorder seen more frequently in these populations. And this is not to say that this is the same sort of autism generally seen in the general population (it’s not).
However, it seems passing strange that Mr. Olmsted, in his extensive canvassing of the Lancaster County Amish communities, did not run across a few of these children. They are, after all, autistic, even if they weren’t vaccinated.
Three possibilities leap to mind (there may be others):
[a] Mr. Olmsted didnt look all that carefully for autistic children, having already concluded that there wouldn’t be any.
[b] Mr. Olmsted found these autistic children, but didn’t count them - either because he (as a trained neurologist and developmental pediatrician) didn’t feel that they had real autism or because it conflicted with his forgone conclusion.
[c] The Amish families - being somewhat suspicious of “outsiders” (not without good reason) - didn’t confide the details of their family medical issues with Mr. Olmsted.
My money is on [a], with a bit of [c] thrown in for good measure.
One thing my thesis advisor told me early in my education:
“If you don’t look for contradictory data, you won’t find it. But your critics will.”
Prometheus
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Miscellaneous Mercury Nonsense
March 26th, 2006
A few things that aren’t big enough for a full posting but are interesting enough.
Geiers’ Testosterone-Mercury Binding Model Full of Sheet:
My fond compliments to the University librarians who located and delivered to my desk the article that is the sole published report of a complex forming between testosterone and mercury:
Cooper A, Gopalakrishna EM, Norton DA. The crystal structure and absolute configuration of the 2:1 complex between testosterone and mercuric chloride. Acta Crystallogr B. 1968 Jul 15;24(7):935-41.
My favorite part of the article has to be the authors description of how the crystal was made:
“…by dissolving equimolar amounts of testosterone and mercuric chloride in minimal hot benzene.”
For those not facile with chemistry-speak, the authors took equal numbers of molecules of testosterone and mercuric chloride and dissolved the mixture in the minimal amount of hot benzene that it took to dissolve the mixture.
This is not a condition even remotely similar to anything found in living tissue - of any vertebrate species. In other words, it isn’t likely to happen in autistic children unless you dissolve them in hot benzene.
The Geiers’ Seek Data Post Hoc to Support Recent Assertions made about Autism Statistics:
Apparently, the recent JPandS article by the dynamic duo has been “outed” by none other than Joseph of “Autism - Natural Variation” . It seems that G&G didn’t check to be sure that their data was what they thought it was but just went ahead and fit it to their hypothesis anyway.
Now that they’ve been “outed” (again), they are frantically seeking new data from the California DDS to shore up their foundering conclusions. Joseph, who has been in contact with the editors of JPandS, feels that a retraction is in the offing. Personally, I think that the chances of JPandS asking the Geiers for a retraction is slim, at best - it’s not their style. However, stranger things have happened.
Legitimate Clinical Laboratory Provides Reference Range for Lead after “Provocation” with DMSA or EDTA:
LabCorp, a legitimate clinical laboratory company headquartered in Burlington, North Carolina, has extensive experience in occupational testing. They are no fly-by-night company, having over 1000 testing facilities nationwide and 35 primary laboratories. Their reference values for urinary lead just happen to include values for people after taking DMSA or EDTA for chelation. Unfortunately, they do not have similar values for mercury, but a quick look at the lead values may give some idea of what those might be.
LabCorp’s reference values for “environmental exposure” to lead is 0 - 50 mcg/day, which is a bit higher than most labs. Their reference range for testing done after chelation with EDTA (1 gram IV) or DMSA (2 grams PO) is 0 - 600 mcg/day. Now, since DMSA is a much better chelator for mercury than it is for lead, even if we stick to the 1:12 ratio that LabCorp has found for lead, we should still be erring well on the side of calling someone “mercury- toxic” when they are not.
So, if 0 - 15 mcg/day is within the “normal” range for urine mercury without chelating, then the upper limit of the reference range after chelation should no less than 180 mcg/day. Most likely, the upper limit after chelation will be significantly higher than that, given the amounts of mercury DMSA pushes out of the kidneys (and DMPS is even better at getting mercury out of the kidneys).
I’d be interested in hearing from anyone who has had themselves or their children tested for mercury after DMSA or DMPS (don’t tell me if you’ve given your children EDTA, I’d just have to call Child Protective Services). No names, please! But urine mercury values would be most welcome.
Prometheus
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Mercurial Laboratories
March 23rd, 2006
One of the recurrent themes in the mercury-causes-autism propaganda is use of a certain, select group of laboratories to make the “diagnosis” of “mercury toxicity”. Easily the most prominent of this “select” group is Doctor’s Data, Inc of St. Charles, Illinois.
It may not seem fair to pick on Doctor’s Data (DDI), since they are probably no worse (and no better) than any of their mail-order lab competitors. But Doctor’s Data has been the “lab of choice” for a number of mercury-autism “studies”, so its reliability has more bearing on the validity of the “research” supporting the mercury-autism connection.
Well, the first thing that pops up on a careful examination of the DDI website is that their reference ranges (sometimes called “normal ranges”) are different (lower) than those used by the more standard clinical laboratories (0 – 5 mcg/day vs 0 – 15 mcg/day). Now, I’ve heard it argued that their assays are more “sensitive”, and so a lower reference range is appropriate, but this doesn’t hold up to careful scrutiny.
To begin with, DDI is using the exact same equipment that the clinical lab at the local University hospital is using, and also the same as used by nationwide clinical laboratories (where clinics and smaller hospitals send their urine mercury samples). Besides, a greater sensitivity only lowers the minimum detectable level; it doesn’t affect the value.
Some of you are probably asking yourselves, “What does it matter? Mercury is bad, so any amount is bad…right?”
Wrong.
Mercury is a ubiquitous element – it is found everywhere on the planet, even in pristine alpine lakes. It is in the air you breathe, the food you eat and the water you drink. It comes from burning fossil fuels, industrial processes, broken fluorescent tubes (less with the newer ones) volcanic eruptions and deep sea hydrothermal vents. In short, everybody has mercury in their bodies from the time they are conceived until (and after) they die.
As a result, it is expected that any urine sample (or blood or hair or…) from any person will have some amount of mercury in it. Analyses that fail to show mercury are simply not sensitive enough – it’s there, they just aren’t seeing it. And none of this has any impact on DDI’s decision to use an upper limit of “normal” that is one third of the generally accepted value.
I suppose we ought to first talk a bit about how these “normal ranges” are determined. To begin with, they are not simply “agreed upon” or “generally accepted” values (unlike some of the EPA and OSHA limits). The “normal” or reference range is determined by measuring the values of at least one thousand “healthy, normal” volunteers. I put “healthy” and “normal” inside quotation marks because there is some debate about how these characteristics are defined and determined. The general practice is to use college students, often athletes, who report no health problems. For tests which may show age related changes (e.g. testosterone), volunteers of the appropriate age (and/or sex) are recruited. This is called “normalization” or “norming”.
In the end, all of the values for the thousand or more “healthy, normal” volunteers are collated and the “normal” or reference range is set to include 95% of the values obtained. This leaves 5% of the presumably “healthy, normal” population outside of the “normal” range, which is why I put “normal” in quotes and why the preferred term is “reference range”.
One of the conundrums in clinical laboratory medicine is this 5% of the “normal” population that – by definition – is outside of the reference range. This is particularly problematic when you are running a battery or “panel” of tests, since each one of them has a reference range that excludes 5% of the “healthy, normal” population. It is a relatively simple exercise in probability to find how many tests you have to do to reach the point where there is a greater than 50% chance that one of the results will be “abnormal” (i.e. outside the reference range) in a person who is “healthy” and “normal”[Answer: 14].
Good, responsible clinicians are aware of this fact and guide their interventions accordingly. Less responsible clinicians may see this as an opportunity. After all, if you order a “panel” of 30 tests, there is a 78.5% chance that a “healthy, normal” person will have at least one abnormality. And this applies when the tests have been properly normalized (tested with over one thousand “healthy, normal” volunteers) and have the appropriate reference ranges used. What happens if you change those assumptions?
Let’s start with proper normalization. One technique used by labs when they are performing a laboratory test that has never had a formal normalization process is to use a much smaller group of “healthy, normal” volunteers (up to one hundred) and create a provisional normalization. Because of the potential for errors and random variation with such a small test group, such tests are usually marked as “experimental”, “provisional” or other such verbiage – to warn the unwary that these tests should not be given too much credence.
Another, less valid approach (often used by mail-order or “do-it-yourself” labs) is to use the specimens provided as a source of the values for the normalization process. This is fraught with errors, since the specimens are usually being sent because the client suspects that they have a health problem. Although, for the mail-order or “do-it-yourself” laboratories, this may be less of a problem, since they seem to cater to the “worried well” segment of the population.
One rather less savory technique seen at some laboratories (of the mail-order or “do-it-yourself” variety, exclusively) is to set the reference range of a test as the mean (“average”) of the “normal” values (see above), plus and minus one standard deviation. For those not familiar with the standard deviation, it is a measure of the variation within a group – the bigger the number, the wider the range of values around the mean. A handy feature of the standard deviation is that – for a population with a “normal” (this time, “normal” means “bell shaped distribution curve”) distribution – the mean plus and minus two standard deviations encompasses about 95% of the population (95.5%). Plus and minus one standard deviation from the mean only encompasses 68.3% of the population, which would leave 31.7% of the ”healthy, normal” population outside of the reference range.
Now, if you use the +/- one standard deviation stratagem, it takes a lot fewer tests to get an abnormal result from a “healthy, normal” person. In fact, the chance of having one “abnormal” result is over 50% after only two tests. A meager panel of five tests raises the chance to over 85%. This can be a real boon to those looking for an abnormal result – any abnormal result – to show their worried-well patients.
This brings us back to DDI and their…”individualistic” reference ranges. Let’s see if we can estimate how changing the reference range might impact their reports.
Looking at urine mercury, DDI advertises that they use ICP-MS (inductively-coupled plasma – mass spectroscopy) for their analysis. Perkin-Elmer, a manufacturer of those machines, lists the limit of detection (LOD – the lowest concentration it can detect) of its ICP-MS as 0.1 ppb (parts per billion, or mcg/liter), which works out to around 0.2 mcg/day, given average urine output. Compared to DDI’s upper limit of 5 mcg/day, this is close enough to zero to make no significant difference, and that assumption will give DDI a bit more leeway.
Now, the distribution of urine mercury values – even in the “healthy, normal” population – is not going to be a normal distribution (the nice “bell-shaped curve” of basic statistics). The values will be clustered nearer zero, as has been shown by a number of studies. In fact, the distribution can be modeled as a normal distribution (“bell-shaped curve”) folded in half at the mean (the peak of the curve). This assumption greatly simplifies the math and, in the process, gives DDI yet another break, since it places the mean at zero and thus broadens the standard deviation (mathematical tricks – don’t try this at home, or on your homework).
If we do this, and assume that the reference range used by the grand majority of clinical laboratories is two standard deviations from the mean, this gives us the following:
Mean: 0 mcg/day (yes, I know this is unrealistic, but it gives the advantage to DDI)
Standard deviation: 7.5 mcg/day
In a two-tailed normal curve, the mean plus and minus two standard deviations encompasses 95.5% of the population. In this “folded”, one-tailed distribution, the mean (0 mcg/day) plus two standard deviations (no minus, since that would lead to negative numbers, which would be really ridiculous) will encompass 95.5% of the population and should define the reference range.
With these assumptions, which clearly give the advantage to DDI, the upper reference range used by DDI (5 mcg/day), is the mean plus 2/3 of a standard deviation. This range only encompasses 49.5% of the “healthy, normal” range, so you reach the 50% probability of a “false positive” (abnormal result in the absence of any disease) with a single test.
Remember, the assumptions used to construct this simple model were grossly biased in favor of showing DDI in a good light, so it is likely that their reference range is even worse than the model shows.
To be fair, DDI’s reference ranges are close to or identical to the “standards” on some of their tests (cadmium, for instance). However, their reference ranges for arsenic and antimony were three times higher than the standard ranges used by most clinical labs. As my son would say, “Go figure.”
DDI steps “over the line” again with their lead reference range, which is given as 0 – 20 mcg/day, against 0 – 31 mcg/day for the other laboratories. Using the same model as above, we get a pretty similar answer – DDI’s reference range only encompasses 81.8% of the “healthy, normal” population.
If DDI had stuck strictly to the established reference ranges for its DDI’s “Urine Toxic Metals” panel (15 metals, from aluminum/aluminium to uranium), there would be a 53.7% chance of a single false positive result (an abnormal result in the absence of disease). By changing the reference ranges on just mercury and lead (two “hot topics” in autism, by the way), and even giving them credit for raising the reference ranges on antimony and arsenic (assuming that these tests now have a 2% false positive rate), the overall risk of a single false positive goes to over 75% [77.9%].
Let me say that out again. By reducing the reference range on lead and mercury – even if we can assume that they are using valid reference ranges for the others (such as tin, platinum and thallium, for which large normative studies have not been done), the chance that a perfectly healthy, normal person would get back one abnormal test result goes to over 75%. And that abnormal result is most likely to be either mercury or lead.
Is it any wonder that DDI is the “lab of choice” for people trying to find a connection between mercury and autism?
Prometheus.
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Armchair Science vs Real Science
March 12th, 2006
In American football, there is a term for those who sit in front of the telly and pontificate on what they would have done if they had been in charge of the game. They are called “Armchair Quarterbacks”. As I understand it, it is not meant to be a compliment.
In the world of pseudoscience and quackery - and especially in the world of “alternative” autism therapies - there are a group of people who sit in front of television cameras and pontificate on what “might” cause autism and what “might” treat it. I think the term “Armchair Scientist” fits these people well.
As with “Armchair Quarterback”, “Armchair Scientist” is not a flattering term.
An Armchair Scientist gets to sit and speculate about what might be without ever having to do the hard work of actually doing any research to find out what is. The average Armchair Scientist doesn’t even bother to review the published literature - they just make it up from what people have told them, what they’ve read on the Internet and what comes to them in their dreams.
However, the more pernicious of the Armchair Scientists have a pasing familiarity with the literature and cite it to their benefit. Several good examples of Armchair Scientists can be found on the FAIR Autism Media website. My personal favorites from this site are the dynamic (definitely sarcasm - see the video) duo of Geier and Geier (pere et fils).
In their video clip from the FAIR site, Geier and Geier expound at length (in a performance that can only be described as “petrified” - it’s too stiff to be “wooden”) about how they “discovered” that testosterone is the linchpin to explaining:
[1] How thimerosal invaccines causes autism (their bread and butter - literally).
[2] How the myriad of disparate and illogical autism treatments “work”.
[3] Why more boys than girls are autistic.
It’s a masterful piece of work, to be sure, and it would be a magnificent addition to the corpus of medical knowledge except for one small problem…
They don’t have any data.
They begin with a stirring description of how they “found” that mercury inhibited a key enzyme in the pathway (more properly, the web of interlocking synthesis pathways) from cholesterol to testosterone and how this discovery led them to the belief (unsupported, as yet, by any data) that this was the key to the autism puzzle. Their “discovery” was from a paper by Ryan RA and Carrol J, Studies on a 3beta-hydroxysteroid sulphotransferase from rat liver (1976).
In this paper, Ryan and Carrol describe that the enzyme 3beta-hydroxysteroid sulphotransferase (EC 2.8.2.2) was, “…inhibited by p-chloromercuribenzoate and HgCl2″. However, if you do a search of Medline for that enzyme, you will find that it is regulated, stimulated and inhibited by a wide variety of substances besides mercury.
So, let’s look for a moment at some of the other claims they make on this video.
They cite a “study” by Boyd Haley, PhD who reportedly exposed neurons in cell culture and found that testonsterone enhanced the toxicity of mercury. This would be interesting - if not earth-shattering - news, except that it hasn’t been published anywhere. Boyd Haley has a long list of publications and his name alone was able to get unadulterated twaddle published in an otherwise respectable journal, so I doubt the lack of publication is due to the infamous “conspiracy of silence”.
A possible explanation for this absence of publication is that Boyd Haley doesn’t feel confident enough of his results to embarrass himself in front of his peers. It’s one thing to show video of neurons “unraveling” to a group of credulous parents - it’s another thing entirely to show the same piece of work to people who know the “tricks”.
That said, there are several studies that have looked at the role of testosterone in mercury poisoning (which should never be confused with autism - the symptoms and signs are completely different). A study by Barregard, Lindstedt, Schutz and Sallsten, Endocrine function in mercury exposed chloralkali workers (1994), showed that “Serum total testosterone, but not free testosterone, was positively correlated with cumulative Hg exposure.”
Another study by Tanaka, Naganuma, Miura and Imura, Role of testosterone in gamma-glutamyltranspeptidase-dependent renal methylmercury uptake in mice (1992), showed that “Renal mercury content in 4-week-old male mice was twofold higher than that of females and increased with age, but remained constant in females.” and “Seven days after castration of 4-week-old male mice, both renal mercury content and gamma-GTP activity were decreased to the levels in females.”
On the other hand, a study by Mohamed, Burbacher (a familiar name) and Mottet, Effects of methyl mercury on testicular functions in Macaca fascicularis monkeys (1987), showed “The MeHg-induced increase in semen abnormalities was not accompanied by any significant changes in serum levels of testosterone.”
Even more interesting is a study by Hirayama,Yasutake and Inoue, Effect of sex hormones on the fate of methylmercury and on glutathione metabolism in mice (1987), which found:
“Twenty-four hours after oral administration of MeHg, urinary Hg levels were significantly higher in males than in females. Tissue Hg levels of males were higher in the kidney, but lower in the brain, liver and plasma than those of females. The fate of injected MeHg in castrated males was similar to that in normal females except for its brain levels. This feminization of the mercurial behavior in the castrated males was restored by treating with testosterone propionate (TP). When control mice were treated with TP, urinary excretion of Hg increased in both sexes, whereas renal Hg level increased only in females. Administration of estradiol benzoate (EB) to males decreased the renal accumulation and urinary excretion of Hg, whereas its hepatic levels
increased.”
In short, Hirayama et al [thanks Clone3G, for the reference!] found that testosterone protected the brain and increased mercury excretion. And that estrogen made the mice more susceptible to mercury poisoning. Quite the opposite of what Geier and Geier speculate might be happening in autistic children!
So, the connection between mercury and elevated testosterone - which seems so solid to the Geiers - is not clear at all, even at overtly toxic levels. Nor does the idea that testosterone impairs mercury excretion or increases mercury toxicity seem to be holding water.
The real laugh in the show was when the Geiers described how mercury “coordinated” the binding of testosterone into large “sheets” and “matrices” that were resistant to breakdown by enzymes. They based this - so they said - on crystallographic data. Since there is only one report of co-crystallization of testosterone and mercury [Cooper A, Gopalakrishna EM, Norton DA, The crystal structure and absolute configuration of the 2:1 complex between testosterone and mercuric chloride (1968)], it seems that is the source of this datum.
Apart from the fact that the processes used to crystallize testosterone (or most any other biological molecule) for X-ray crystallography are not happening in the body, there are some flaws in this “reasoning”:
[1] If the mercury is complexed into a matrix of testosterone and mercury, it is not available to cause problems. It would seem that these “sheets” of testosterone would be an ideal way to sequester mercury away from delicate brain tissue, which would leave open the question of why the Geiers want to reduce testosterone.
[2] Mercury doesn’t complex with carbon, oxygen or hydrogen very well - it “prefers” sulfur, but will complex with phosphorus or nitrogen in a pinch. below are the structures of several compounds related to testosterone (including testosterone itself). For those unfamiliar with the notation, the lines have a carbon atom at each end unless a letter is present.
Clearly, there is no high-affinity spot for mercury to attach.
[3] How is mercury - a brainless atom that cannot read structure diagrams - to know that it should attach to testosterone and not one of the several “look-alike” molecules? How many of the intelligent life-forms reading this blog can spot the testosterone molecule?
Here’s the “key” for the above test:
So, we have no data to support the idea that testosterone binds preferentially to mercury, that mercury bound to testosterone (if it were possible) would be bioavailable (capable of doing harm). We also have no data that mercury causes an increase in DHEA (as proposed by Geier and Geier) or that testosterone impairs excretion of mercury. What’s left?
Prometheus
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Undead Bad Science
March 8th, 2006
One nasty thing about peudoscience - it doesn’t die quietly.
The dreadfully inept “study” of mercury in the hair of autistic children - saved as momentos of their first haircut - by Holmes, Blaxill and Haley (2003) continues to spread misinformation and confusion. A quick check on “Web of Science” revealed that it had been cited in other papers fifteen times! Of course, it should come as no surprise that at least six of those citations were in articles by the dynamic duo of pseudoscience, Geier and Geier (see here and here, also here, here, here and here).
In a nutshell, the Holmes et al “study” compared the mercury in the “first baby haircut” hair of 94 autistic children and 45 “neurotypical” controls. Disregarding so many procedural, technical and analytical flaws that they almost defy counting, the “data” they came up were these:
Autistic children’s hair mercury levels: 0.47 ppm (+/- 0.28 ppm)
Control children’s hair mercury levels: 3.63 ppm (+/- 3.65 ppm)
Now, Holmes (a radiation oncologist who was in “alternative” medical practice at the time), Blaxill (an MBA) and Haley (a somewhat conflicted PhD chemist) concluded that, since the autstic children had lower hair mercury than the controls, that autistic children were unable to excrete mercury.
Huh?!?
Mind you, they offered no data to support that startling (if not ridiculous) conclusion, nor does anything known about mercury “excretion” in hair support that line of “reasoning”. As far as I can tell, they just made it up rather than face what the data (such as it was) told them - that mercury had nothing to do with autism (actually, the data suggest that mercury might protect children from autism - another unlikely possibility).
Now, come along with me for a minute as we take a look at another study of hair mercury. This study, published in 2004, was part of the National Health and Nutrition Examination Survey of 1999-2000 and looked at the hair mercury levels of 838 “normal” children ages 1 - 5. This is roughly the same age range of the hair samples Holmes et al examined. The NHANES results, however, were different:
Children’s hair mercury levels: 0.22 ppm (+/- 0.04 ppm)
This puts the Holmes et al conclusions in a different light, doesn’t it? The autistic children in the Holmes et al study had over twice the mean hair mercury level of the NHANES group (of 838 children) and the Holmes et al controls had hair mercury levels of over sixteen times the NHANES level.
What are they feeding those kids?
Well, the only conclusion that you can draw from that data is that the Holmes et al study is garbage. My suspicion is that their laboratory - Doctor’s Data - is the cause of the outrageously high levels of mercury found in the children - especially the control children.
So, I hope that this stake through the heart will help this abysmal study finally rest in the obscurity that it so richly deserves.
I doubt it, though - the undead always rise again.
Prometheus
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