Monday, April 23, 2007

But we have to do something!

I always find a little shiver of fear going down my spine whenever I hear someone - especially someone in elected office - say the words, "We have to do something about [X]!"

In my experience, those words have been the prelude to innumerable disasters, debacles and misadventures. The problem is that the urge to action is rarely accompanied by any planning or investigation. What we end up with when we rush to "do something!" is the equivalent of "Ready. Fire! Aim."

In other words, we miss the mark. In fact, we're lucky if we don't hurt somebody in the process.

Over the past several years, I have heard a number of parents with autistic children say, "We can't wait for scientific studies, we have to do something for our children!" While I can completely sympathize with them, I continue to urge caution. Doing something is only better than doing nothing if "something" isn't harmful.

Why do I bring this up, you might ask?

In February, a study was published that showed - for the first time - that treatment with DMSA (a chelating agent) can improve the intellectual functioning of lead-poisoned rats. This was a big deal because human studies (on children poisoned by lead-containing paint) had failed to show any improvement in behavioral or neuropsychological development.

Unfortunately, the study also showed that treating rats who were not lead-poisoned decreased their cognitive abilities. Permanently.

Now, people who are treating their children with DMSA for mercury poisoning would be right to be concerned about these findings, especially if they are relying on doubtful laboratory tests to determine that their children are "mercury poisoned". And those folks who are treating their autistic children with DMPS have no reason to smirk. There is currently no known mechanism to explain these cognitive impairments, so DMPS could be just as bad...or worse.

I hadn't planned to 'blog about this study - too many unanswered questions - but then I got an disturbing piece of news. It seems that a proposed autism-chelation study is being held up while the researchers test the DMSA for lead and mercury. I'm still trying to get confirmation of this, but it seems important enough for parents to know right now.

DMSA and DMPS are absolutely wizard at binding to lead, mercury, cadmium, arsenic and other "heavy metals". It's what they do. As a result, they will grab onto and carry along any lead, mercury, cadmium... that they come in contact with during their synthesis and subsequent handling. Given the ubiquitous nature of lead, mercury and arsenic, it is not improbably that these chelating agents could come in contact with - and grab onto - some in their progress from synthesis to final user.

Might this be the reason that so many parents using chelation report that the mercury is "...pouring out..." of their children? If you're pouring it in, you would hope that it would pour out.

I must emphasize that I have not yet confirmed that the proposed chelation study is being held while they test the DMSA for lead and mercury, but I feel that it is important for people who are doing chelation with DMSA (or DMPS) to get the news.

I'll keep you posted as I know more.



Blogger daedalus2u said...

This is scary. The damage that this may have done to all those chelated children is absolutely horrifying.

DMSA is going to bind to metals that bind to sulfur. That would be mercury, lead, arsenic, silver gold, but also copper, zinc, and perhaps selenium. Perhaps iron, but the chemistry of iron is somewhat different, and iron isn't so much used as a regulatory molecule the way zinc is. Iron is held in its own transport molecule ferritin, selenium has its own transport molecule too. Copper and zinc use metallothioneine.

Metal-sulfur clusters are at the heart of many enzymes. Iron-sulfur, copper-sulfur, zinc-sulfur, molybdenum-sulfur, selenium-sulfur, manganese-sulfur. That is probably the most common way that metals are held in the active site of an enzyme, via coordination to sulfur atoms.

I suspect that copper and zinc are the most likely to be affected. Zinc is absolutely essential for the most abundant class of trancription factors, the zinc finger proteins. There are some 900 or so zinc finger proteins that regulate all sorts of stuff having to do with how DNA is regulated.

Any thiol based chelating agent is (I would guess) going to have the same effects. I suspect it isn't a "toxic" effect of the chelation agent, rather what happens when necessary metals are chelated out willy-nilly. You change the relative ratios of them, perturb the natural regulation of them via transciption factors. If it is an effect of perturbed zinc and copper metabolism, then the longer you do it, the worse the effects are going to be.

I can't think of any reason why synthetic chelating agents would have high levels of any heavy metals. The raw materials wouldn't, and the synthesis isn't going to be in lead lined vats (though lead is used in some industrial applications for its corrosion resistance). You could remove lead and mercury from these materials chemically with out much difficulty. I would consider adding a tiny amount of lead and mercury, of a specific isotope, so the entire body burden can be accurately measured by isotope dilution.

I think the reports of high mercury excretion are simply erronious. Like the Branstreet et al paper. It wasn't a "lot" of mercury, it was simply modestly higher than unprovoked urine.

I suspect any delay in the trial going forward is due to the very strong misgivings that a real IRB has in giving a treatment which has the potential for harm, when there is no conceivable basis for help.

In light of this result, they may have trouble getting victims, I mean subjects.

23 April, 2007 19:09  
Blogger Bartholomew Cubbins said...

I can dig for it, but I seem to remember some old experiments that measured the ability for EDTA (and possibly other chelators) to leech metal ions out of glass containers.

Wouldn't that be tragic, that the parents desperately dosing their child with some chelator was actually introducing the metals and in doing so pushing their child's labs from yellow to red. Oh, tragic by all accounts except for the financial advisor of the prescribing "doc" and the homeopathic EDTA salesman.

23 April, 2007 20:50  
Blogger Club 166 said...

Ready. Fire! Aim. That pretty much sums it up.

Thanks for your excellent coverage, as always.

24 April, 2007 06:15  
Blogger Prometheus said...

I want to reiterate that the reports of possible (or suspected) heavy metal contamination of DMSA are still unconfirmed.


24 April, 2007 08:44  
Blogger daedalus2u said...

It occurs to me that most parents who are chelating their children likely are also giving them all sorts of "supplements", eye of newt and all that.

Those supplements are likely sources of heavy metals. They found 20% of the supplements they tested to be dangerously contaminated. The analytical technique used in this study was not very sensitive, and the detection limits are quite high, (5, 20, 10 ppm for Pb, Hg, As). Most foods don't have heavy metals in them because (exceptions being mercury from fish). Eye of newt is probably ok.

The heavy metals could be introduced or concentrated during down stream processing. For example methyl mercury is lipid soluble and when fish oil is processed to concentrate the omega-3 fatty acids, methyl mercury can be concentrated too, depending on the process used.

24 April, 2007 09:53  
Blogger J said...

This brings up a (slightly off-topic) question I have asked myself for some time.
Anyone who has read the anecdotal reports of parents who have had their children tested for mercury toxicity will notice the the phrase invariably used is " the charts!" Any actual chart I have seen copies of, when provoked samples are used, show mercury as being, literally, off the chart.
So my question is: At what point is the chart going to be revised? Charts are typically presented in such a way as to capture the range of possible results, using a rough approximation of bell-curve-type statistics with, perhaps, 1% or less of all results ending up "off the chart". So, considering that seemingly all autistic children end up " the charts", should the chart not be re-calibrated?
Or, alternatively, DD labs could be shut down and DAN! disbanded as a threat to public health. I think I like that option better.

24 April, 2007 11:44  
Blogger María Luján said...

Hi Prometheus
you say
Doing something is only better than doing nothing if "something" isn't harmful.
and I agree with you. The risk/benefits should be properly and carefully considered in terms of "something".

Even when I can understand that some parents choose the path you mentioned, many others like us, analyze carefully and the approach in our case was/is/will be
"We must do the right thing (not "something")and the first one is to properly test to know if there is [X] present, with the best possible info available"
and this is a world of difference- or at least has been- for my son and it was/is/will be not easy.

27 April, 2007 21:08  
Blogger JonHendry said...

It wouldn't surprise me if the people who sell the chelating agents have found that it's most profitable to obtain them *used*.

30 April, 2007 16:40  

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