Dr. Oz and the Arsenic Thing

Let me get this out of the way first: I don’t watch Dr. Mehmet Oz on television.

I did see a show the year before last while I was keeping an older relative company. I can’t tell you what it was about, though, because we weren’t that long into it before my relative suggested that  that I take myself, my twitches, and my sarcastic mumbling to another part of the house.

Consider this a full disclosure of attitude toward Dr. Oz. Consider it also an explanation of why I didn’t see his show last week on the (alleged) dangers of arsenic in apple juice. It was impossible to miss, of course,  the backwash of the critical reaction that followed, my  favorite being Steve Salzberg’s wickedly smart take, “Dr. Oz Tries to be A Scientist” in Forbes. I also enjoyed Pharyngula’s tale of the FDA’s unsuccessful efforts to educate Dr. Oz about arsenic prior to his show. The theme of  the news coverage throughout was, let’s say, unsympathetic.

The primary criticism was that for a man with a medical degree, Dr. Oz didn’t seem to know very much about arsenic. The FDA – rather testily, actually – had pointed out to him that he was testing for total arsenic load. Their objective was that this overstates risk by combining levels of  both inorganic (bad, bad) and organic (not so very bad) arsenical compounds.

On average, inorganic arsenic is considered about 500 times more poisonous that organic arsenic. So a high test number that combined the two but was mostly organic would actually indicate less risk than a lower number that involved more inorganic arsenic.  Unfortunately – for Dr. Oz and his viewers – he either didn’t get this or considered it too complicated for the audience.

As Salzberg pointed out, those combined totals weren’t necessarily reliable anyway. Dr. Oz didn’t follow the standard test practice of sending his samples to multiple labs. Instead he relied on one testing facility. When the FDA sent juice samples from the same lots to other laboratories, the arsenic levels were a fraction of what Dr. Oz reported. All of which leads us to the essential criticism here, that Dr. Oz  sensationalized a non-problem and by doing so irresponsibly frightened consumers of apple juice.

In a cranky, reluctant way, if you’re me, you have to kind of admire the way Dr. Oz responded to this concerted hiss of dismay. He continued to maintain that  arsenic exposure should always be considered a big, bad thing. And he managed to suggest that this big picture was more important than nitpicking whining about things like test accuracy and arsenic classification. He did this well enough that, for instance, U.S. Sen. Charles Schumer, D-NY, asked the FDA to take another look at arsenic levels in apple juice.

So I’m not going to dwell further on the problems with his broadcast; I’m hardly going to mention the issues with shoddy science and the sensationalism. Hardly at all. What I would like to mention, whine about, nitpick, however, is Dr. Oz’s lost opportunity to r illuminate the actual risks. This is arsenic, after all, one of the world’s most important – and fascinating – poisons.

He could have sifted out those organic and inorganic test results, for instance, and helped his viewers to understand what they meant. Arsenic (As) is, after all, a naturally occurring metallic element (sometimes called a metalloid). It’s also one of those elements that likes to partner up, either with organic (carbon-based) compounds or with inorganic (which for these purposes pretty much means no carbon involved).

Fortunately for us, our bodies tend to break down and metabolize away most organic arsenic compounds fairly efficiently. In fact, many of these organic arsenic compounds (such as arsenobentaine, in case you wondered) form naturally in fish and shellfish. Fish-lovers thus receive get a steady low level exposure to organic arsenic, as far as we know,  without reported health effects. A few years ago, there was a suggestion that kelp-based health supplements might contain an arsenic problem, but it foundered – just as Dr. Oz’s apple juice case did – on the type-of-arsenic issue.

We humans – and, in fact, most living creatures, don’t handle inorganic arsenic nearly as well. Arsenic trioxide (AsO3) or white arsenic is one of history’s most famous homicidal poisons – so much so, that back in the 19th century, it was often referred to as the inheritance powder.  By some estimates, inorganic arsenic can be fatal in the amount of 60,000 micrograms (about 1/50th the weight of a penny).

Why is it so dangerous? And don’t we wish that Dr. Oz had used his moment to ask this very question? As it turns out, the answer lies in actually being nitpicky about the question. Inorganic arsenic toxicity has a lot to do with the number of valence bonds the compound possesses.  Valence bonds are created when atoms cling to each other because of an interaction between electrons in their outer shells.

In other words, the higher the valence bond number, the grabbier the compound, the greater its ability to insinuate itself into a living system. The two grabbiest forms of inorganic arsenic are trivalent (three bonds) and pentavalent (five). Pentavalent arsenic can, in fact, do a perfectly lethal job of disrupting cellular metabolism. But toxicologists tend to worry more about trivalent arsenic forms, which are also nasty poisons, more persistent, and much harder to remove from drinking water supplies.

And naturally occurring, inorganic arsenic in drinking water  around the world does real and physical harm. I’ve written about this myself regarding the poisoning of water supplies in countries like Bangladesh. But there’s health risks to go around even in countries like the United States.

In other words, Dr. Oz could have used this arsenic moment to have picked out a real health risk, educated people about it, maybe even saved a few lives and there. And that’s what I hold against him – the careless waste of opportunity -  and that’s why he makes me twitch. Even at this safe distance from a sofa in front of the television set.

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29 Responses to Dr. Oz and the Arsenic Thing

  1. John Rennie says:

    A devastating, perfect argument, Deborah. Thank you.

  2. Mutant Dragon says:

    Mon Dieu amable! Are there no other sites on the Internet, that you go to AN INTELLIGENT DESIGN WEBSITE to find your “favorite definition” of valence-bond theory and covalent bonds??????????

  3. Mutant Dragon says:

    Ack, I am overreacting. I suppose you probably did not know this ISCID is an intelligent design organization. But good heavens! if you want to know more about valence bond theory or MO theory, don’t go THERE! a general or organic chemistry textbook or even our good friends at Wikipedia would be a better place to look. There are plenty of places to get info without turning to sites run by those crazy ID folk.

  4. Peter Caryotakis says:

    Mz. Blum,
    Look at the Arizona Study done well before Dr. Oz ever got hold of this.
    The INORGANIC ARSENIC is the HIGHER of the two components. Who does the testing for the FDA? Does China get a say?
    Do I trust the FDA at all when they were forced to say that the air at Ground Zero was SAFE for the rescue workers???
    It seems to me like the MAD MEN of the Juice Industry are having a field day turning this issue around. Are they lying? NO! But based on the Arizona study I’m damn glad that this is being checked into.
    They got sucker punched by Dr. Oz even though he showed them exactly what he was going to say. No response before. Afterwards….. a campaign equal to any Rovian twisting of the truth.
    LOOK at the data!!
    http://www.doctoroz.com/videos/university-arizona-study?page=3#copy
    http://www.doctoroz.com/videos/university-arizona-study?page=4#copy

  5. Macphee says:

    I too am surprised and disappointed that you would have a link to ISCID as a resource. I hope it was a mistake on your part. It does not add to your credibility.

  6. Deborah Blum says:

    Yeah, should have looked more closely at that source and it’s now gone from the post. I replaced it with Wikipedia. But I do like that very simple definition because, perhaps for obvious reasons in this case, it’s aimed at the general audience and not the scientific one. Even Wikipedia is incredibly complex in this case, making me wish that someone – ACS? – would do a chemistry glossary in service of general science literacy.

  7. Deborah Blum says:

    Well, it does teach me to take a closer look next time I link to a definition. And I replaced it with Wikipedia. Agreed that this blog doesn’t want to go there. But I will say that I wish that any of the many credible scientific sites I looked at offered such a clear and simple definition.

  8. Deborah Blum says:

    I appreciate the tip on further research! I would actually like to do another post on some of the issues with arsenic in the food supply. And there’s some interesting questions about whether organic arsenic may, in some cases, metabolize to inorganic. It came up last year in regard to Roxarsone, the organic arsenic additive that has been put into chicken feed. The manufacturer suspended its sale in order to conduct further tests but it raised some very interesting questions. I wrote about it on this blog as “Playing Chicken with Arsenic.” And I am aware that Dr. Oz has raised this issue.

  9. Deborah Blum says:

    Totally appreciated, John!

  10. Mutant Dragon says:

    If you are not finding a layperson-friendly definition anywhere, I think it may be because you are looking for a couple different things.

    A simple definition of a covalent bond is a chemical bond that involves sharing of electrons between atoms. Valence-bond theory is a quantum-mechanical description of covalent bonds first worked out by the great Linus Pauling (I believe back in the late 20′s — early 30′s). Although many of the concepts from VB theory are very useful in organic chemistry, when people want to do calculations they generally use MO theory, another quantum-mechanical theory of chemical bonding that has proven superior to VB theory in many respects and is easier to use in calculations.

    If you are Googling to look for a definition (I assume that’s how you dug up that ISCID-atrocity) and you Google for “covalent bond”, you’ll get lots of nice layperson-friendly definitions similar to the one above. If you are Googling “valence bond”, however, you’ll get lots of pages on valence bond theory, and those are bound to be somewhat less layperson-friendly. So hopefully that gives you an idea about where to look.

    Sorry for the initial overreaction, but what can I say — I am strongly allergic to IDiots.

  11. Deborah Blum says:

    Yes, same allergy, so I appreciate the catch. And the excellent definition. So glad you follow the blog.

  12. Pascale says:

    I groaned when I heard about the latest from Dr. Oz, but decided in the long run it might be OK. “Apple Juice” is basically sugar water with little nutritional value that has somehow become acceptable for mass consumption by toddlers in a time of increasing obesity. Anything that gets parents to ban this source of empty calories from their homes is OK with me, even if it’s ultimately for the wrong reason.

  13. John Lowe says:

    Nicely done! It was very exasperating to see Dr. Oz with his megaphone completely whiff an opportunity to provide some risk education. Reading this prompted me to go and read again the post on arsenism in Bangladesh. It’s a tragic story but that’s what real arsenic health risks look like.

    I hadn’t heard that the FDA sponsored some laboratory comparisons – a quick check of their web site didn’t say anything about it. I wonder if the data are available anywhere.

  14. AlHubb says:

    I have found it expedient to always do opposite what Dr Oz recommends. He is an alarmist who exploits those who trust his words.

  15. Luis says:

    I wonder if professor Blum has read the Univ. of Arizona, Roberge et al. Presence of Arsenic in Commercial Beverages study. Seems to me that Dr. Oz has data but Prof. Blum has nothing. The link to the study were posted above by Cariotakis. It was not a tip on further research as suggested by Prof. Blum, it was a tip on old but very relevant research that gives Oz all credibility to his point.

  16. John Lowe says:

    I’ve read the study, which can actually be found here:

    http://thescipub.com/abstract/10.3844/ajessp.2009.688.694.

    They do a more careful job of documenting their methods and results, and provide the comparison of total and inorganic arsenic species, confirming what FDA says about Dr. Oz’s study that total arsenic results are not the metric one should use for assessing health risks. They reported finding higher arsenic residues in juices than the FDA has found in its Total Diet Study (TDS), which may or may not be a surprise or meaningful. They question whether or not the TDS study samples enough, which is a worthwhile question, and suggest that vulnerable populations may be at risk based on an extremely sketchy risk assessment (in fairness, they’re paper isn’t a risk assessment but a residue study). Nothing terribly surprising here, and nothing that really validates Dr. Oz’s approach to this subject.

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  19. Bob Hope says:

    I won’t dwell, but there is a love affair in the works. Thanks Deb for the insight, much appreciated …

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  23. Travis says:

    I guess Dr. Oz was right after all. And it was inorganic arsenic. When are you going to write about it?

  24. Van Nguyen says:

    As we’ve found out, who sucker punched who. I am glad that Dr. Oz still stand on his feet after a big blow from FDA and Dr. Visser from ABC accused him of fear monger.

    Please follow this link from FDA studies that was recently updated with eight samples that contain very high level of As that purposely omitted originally. Thanks to Dr. Oz.

    http://www.fda.gov/Food/FoodSafety/FoodContaminantsAdulteration/Metals/ucm273328.htm

    As for you dear Deb., you should at least update this article with the new facts and try to appreciate Dr. Oz a little bit more.

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  27. Well said! You GO, Ms. Fisher! (I realize I’m more than a bit late to the party, but couldn’t let this pass without throwing on my support.) *wanders off to read more recent blog entries*

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