Tag Archives: arsenic

Hazardous homeopathy: ‘ingredients’ that ought to make you think twice

Posted on by

Would you take a medicine made with arsenic? Or deadly nightshade? Lead? Poison ivy?

You’d ask some serious questions first, at least, wouldn’t you? Is it definitely safe? Or, more accurately, are the odds better than even that it will make me better without causing horrible side-effects? Or, you know, killing me?

There ARE medicines that are legitimately made from highly toxic compounds. For example, the poison beloved of crime writers such as Agatha Christie, arsenic trioxide, is used to treat acute promyelocytic leukemia in patients who haven’t responded to other treatments. Unsurprisingly, it’s not without risks. Side-effects are unpleasant and common, affecting about a third of patients who take it. On the other hand, acute promyelocytic leukemia is fatal if untreated. A good doctor would talk this through with a patient, explain both sides, and leave the final choice in his or her properly-informed hands. As always in medicine, it’s a question of balancing risks and benefits.

Would you trust something with no proven benefit and a lot of potential risk? There are, it turns out, a swathe of entirely unregulated mixtures currently being sold in shops and online which clearly feature the substances I listed at the beginning. And more. Because they are all, supposedly, the starting materials in certain homeopathic remedies.

Homeopaths like to use unfamiliar, usually Latin-based, names which somewhat disguise the true nature of their ingredients. Here’s a short, but by no means comprehensive, list. (You might find remedies labelled differently but these are, as far as I can tell, the most common names given to these substances.)

If you haven’t heard of some of these, I do urge you to follow the links above, which will largely take you pages detailing their toxicology. Spoiler: the words “poison”, “deadly” and “fatal” feature heavily. These are nasty substances.

There are some big ironies here, and I’m not referring to the metal. For example, a common cry of anti-vaccinationists is that vaccines contain animal tissues – anything and everything from monkey DNA to dog livers. But many also seem to be keen to recommend homeopaths and courses of homeoprophylaxis – so-called “homeopathic vaccines” – which use bodily fluids such as pus and blood as starting materials.

Now, at this point I’m sure some of you are thinking, hang on a minute: aren’t you always telling us that “the dose makes the poison“? And aren’t homeopathic remedies diluted so much that none of the original substance remains, so they’re just placebos?

Yes, I am, and yes, they are.

Does anyone test homeopathic remedies to make sure there’s nothing in them….?

In THEORY. But here’s the problem: who’s testing these mixtures to make sure that the dilutions are done properly? And how exactly are they doing that (if they are)?

One technique that chemists use to identify tiny quantities of substance is gas chromatography (GC). This is essentially a high-tech version of that experiment you did at school, where you put some dots of different coloured ink on a piece of filter paper and watched them spread up the paper when you put it in some water.

GC analysis is brilliant at identifying tiny quantities of stuff. 10 parts per million is no problem for most detectors, and the most sensitive equipment can detect substances in the parts per billion range. Homeopathy dilutions are many orders of magnitude higher than this (30c, for example, means a dilution factor of 1060), but this doesn’t matter – once you get past 12c (a factor of 1024) you pass the Avogadro limit.

This is because Avogadro’s number, which describes the number of molecules in what chemists call a “mole” of a substance, is 6×1023. For example, if you had 18 ml of water in a glass, you’d have 6×1023 molecules of H2O. So you can see, if you’ve diluted a small sample by a factor of 1024 – more than the total number of molecules of water you had in the first place – the chances are very good that all you have is water. There will be none of the original substance left. (This, by the way, is of no concern to most homeopaths, who believe that larger dilutions magically produce a stronger healing effect.)

What if the sample ISN’T pure water after it’s been diluted?

If you carried out GC analysis of such a sample, you should find just pure water. Indeed, if you DIDN’T find pure water, it should be cause for concern. Potassium cyanide, for example, is toxic at very low levels. The lethal dose is is only 0.2-0.3 grams, and you’d suffer unpleasant symptoms long before you were exposed to that much.

So what if the dilutions somehow go wrong? What if some sample gets stuck in the bottle? Or on the pipette? Or a few dilution steps get skipped for some reason?

Are these largely unregulated companies rigorously quality-checking their remedies?

Well, maybe. It’s possible some producers are testing their raw materials for purity (ah yes, another question: they CLAIM they’re starting with, say, arsenic, but can we be certain?), and perhaps testing the “stability” of their products after certain periods of time (i.e. checking for bacterial growth), but are they running tests on the final product and checking that, well, there’s nothing in it?

And actually, isn’t this a bit of a conflict? If the water somehow “remembers” the chemical that was added and acquires some sort of “vibrational energy”, shouldn’t that show up somehow in GC analysis or other tests? If your tests prove it’s pure water, indistinguishable from any other sample of pure water, then… (at this point homeopaths will fall back on arguments such as “you can’t test homeopathy” and “it doesn’t work like that”. The name for this is special pleading.)

A warning was issued in the U.S. after several children became ill.

Am I scaremongering? Not really. There’s at least one published case study describing patients who suffered from arsenic poisoning after using homeopathic preparations. In January this year the U.S. Food and Drug Administration issued a warning about elevated levels of belladonna (aka deadly nightshade) in some homeopathic teething products. Yes, teething products. For babies. This warning was issued following several reports of children becoming ill after using the products. The FDA said that its “laboratory analysis found inconsistent amounts of belladonna, a toxic substance, in certain homeopathic teething tablets, sometimes far exceeding the amount claimed on the label.”

Now, admittedly, I’m based in the U.K. and these particular teething remedies were never readily available here. But let’s just type “homeopathy” into the Boots.com (the British high-street pharmacy) website and see what pops up… ah yes. Aconite Pillules, 30c, £6.25 for 84.

What happens if you search for “homeopathy” on the Boots.com website?

Have you been paying attention lovely readers? Aconite is…. yes! Monkshood! One of the most poisonous plants in the garden. Large doses cause instant death. Smaller doses cause nausea and diarrhea, followed by a burning and tingling sensation in the mouth and abdomen, possibly muscle weakness, low blood pressure and irregular heartbeat.

I must stress at this point that there is no suggestion, absolutely none whatsoever, that any of the products for sale at Boots.com has ever caused such symptoms. I’m sure the manufacturers check their preparations extremely carefully to ensure that there’s absolutely NO aconite left and that they really are just very small, very expensive, sugar pills.

Well, fairly sure.

In summary, we seem to be in a situation where people who proclaim that rigorously-tested and quality-controlled pharmaceuticals are “toxic” also seem to be happy to use unregulated homeopathic remedies made with ACTUALLY toxic starting materials.

I wonder if the new “documentary” about homeopathy, Just One Drop, which is being screened in London on the 6th of April will clarify this awkward little issue? Somehow, I doubt it. Having watched the trailer, I think it’s quite clear which way this particular piece of film is going to lean.

One last thing. Some homeopathic mixtures include large quantities of alcohol. For example, the Bach Original Flower Remedies are diluted with brandy and contain approximately 27% alcohol (in the interests of fairness, they do also make alcohol-free versions of some of their products and, as I’ve recently learned, they may not be technically homeopathic). Alcohol is a proven carcinogen. Yes, I know, lots of adults drink moderate quantities of alcohol regularly and are perfectly healthy, and the dose from a flower remedy is minuscule, but still, toxins and hypocrisy and all that.

There are cheaper ways to buy brandy than Bach Flower Remedies.

Amusingly, the alcohol in these remedies is described an “inactive” ingredient. It’s more likely to be the only ACTIVE ingredient. And since Flower Remedies retail for about £7 for 20 ml (a mighty £350 a litre, and they’re not even pure brandy) may I suggest that if you’re looking for that particular “medicine” you might more wisely spend your money on a decent bottle of Rémy Martin?

Like the Chronicle Flask’s Facebook page for regular updates, or follow @chronicleflask on Twitter. In need of a groovy new mug for your oh-so-healthy coffee? Check out this page.

All comments are moderated. Abusive comments will be deleted, as will any comments referring to posts on this site which have had comments disabled.

Feet of clay? The science of statues

Posted on by
Concept art for the Terry Pratchett statue (c) Paul Kidby

Concept art for the Terry Pratchett statue (c) Paul Kidby

Yesterday we received the exciting news that a statue to commemorate Sir Terry Pratchett and his work has been approved by Salisbury City Council. Hurrah! So, even if we don’t quite manage to get octarine into the periodic table (and thus into every science textbook for ever more), it’s looking very likely that there will still be something permanent to help keep his memory alive.

But this got me thinking about everyday chemistry (who am I kidding, I’m always thinking about everyday chemistry!) and, in particular, bronze – the material from which the statue will be made.

Bronze, I hear you say, what’s that good for apart from, well, statues? And maybe bells? Is it really that interesting?

Well, let’s see. Bronze is an alloy. Alloys are mixtures that contain at least one metal, but they’re stranger than the word ‘mixture’ might perhaps suggest. Imagine combining, say, sand and stones. You still be able to see the sand. You could see the stones. You could, if you could be bothered to do it, separate them out again. And you’d expect the mixture to behave like, well, stony sand.

Alloys aren’t like this. Alloys (other well-known examples include steel, brass and that silver-coloured stuff dentists use for filling teeth) look, on all but the atomic level, like pure metals. They’re bendy and shiny, they make pleasing ringing sounds when you hit them and they’re good electrical conductors. And unlike more simple mixtures, they’re difficult (though not impossible) to separate back into their constituents.

Perhaps the most interesting this about alloys is that their properties are often very different to any of the elements that went into making them. Bronze, in particular, is harder than either tin or copper, and hence The Bronze Age is so historically significant. Copper is one of the few metals that can (just about) be found in its pure form, and so is one of the oldest elements we know, going back at least as far as 9000 BC. But while quite pretty to look at, copper isn’t ideal for making tools, being fairly soft and not great at keeping an edge. Bronze, on the other hand, is much more durable, and was therefore a much better choice for for building materials, armour and, of course, weapons. (War, what is it good for? Er, the development of new materials?)

Hephaestus was the God of fire and metalworking; according to legend he was lame.

Hephaestus was the God of metalworking. According to legend he was lame, could it have been because of exposure to arsenic fumes?

Today we (well, chemists anyway) think of bronze as being an alloy of tin and copper, but the earliest bronzes were made with arsenic, copper ores often being naturally contaminated with this element. Arsenical bronzes can be work-hardened, and the arsenic could, if the quantities were right, also produce a pleasing a silvery sheen on the finished object. Unfortunately, arsenic vaporises at below the melting point of bronze, producing poisonous fumes which attacked eyes, lungs and skin. We know now that it also causes peripheral neuropathy, which might be behind the historical legends of lame smiths, for example Hephaestus, the Greek God of smiths. Interestingly, the Greeks frequently placed small dwarf-like statues of Hephaestus near their hearths, and this is might be where the idea of dwarves as blacksmiths and metalworkers originates.

Tin bronze required a little more know-how (not to mention trade negotiations) than arsenical bronze, since tin very rarely turns up mixed with copper in nature. But it had several advantages. The tin fumes weren’t toxic and, if you knew what you were doing, the alloying process could be more easily controlled. The resulting alloy was also stronger and easier to cast.

teaspoon in mugOf course, as we all know, bronze ultimately gave way to iron. Bronze is actually harder than wrought iron, but iron was considerably easier to find and simpler to process into useful metal. Steel, which came later, ultimately combined superior strength with a relatively lower cost and, in the early 20th century, corrosion resistance. And that’s why the teaspoon sitting in my mug is made of stainless steel and not some other metal.

Bronze has a relatively limited number of uses today, being a heavy and expensive metal, but it is still used to make statues, where heaviness and costliness aren’t necessarily bad things (unless, of course, someone pinches the statue and melts it down – an unfortunately common occurrence with ancient works). It has the advantages of being ductile and extremely corrosion resistant; ideal for something that’s going to sit outside in all weathers. A little black copper oxide will form on its surface over time, and eventually green copper carbonate, but this is superficial and it’s a really long time before any fine details are lost. In addition, bronze’s hardness and ductility means that any pointy bits probably won’t snap off under the weight of the two-millionth pigeon.

So how are bronze statues made? For this I asked Paul Kidby, who designed the concept art for the statue. He told me that he sculpts in Chavant, which is an oil-based clay. It’s lighter than normal clay and, crucially, resists shrinking and cracking. He then sends his finished work away to be cast in bronze at a UK foundry, where they make a mould of his statue and from that, ultimately (skipping over multiple steps), a bronze copy. Bronze has another nifty property, in that it expands slightly just before it sets. This means it fills the finest details of moulds which produces a very precise finish. Conveniently, the metal shrinks again as it cools, making the mould easy to remove.

And just for completeness, Paul also told me that the base of the statue will most likely be polished granite, water jet cut with the design of the Discworld sitting on the back of Great A’Tuin. I can just imagine it – it’s going to be beautiful.

—

Follow The Chronicle Flask on Facebook and Twitter for regular updates.

Bronze, humbugs, wallpaper and electronics: what’s your favourite element?

Posted on by

As a chemistry teacher I’m sometimes asked for my favourite element. Don’t tell anyone, but I don’t really have a single favourite. That would be a terribly boring answer though, so I usually pick something to make a relevant point. Carbon, for example, for being the stuff of life, for having a whole third of chemistry – organic chemistry – devoted to its compounds, and because diamonds are fascinating and really very pretty things. Or sometimes I go for xenon, for being a noble gas, for its potential use as an anaesthetic, and just because its name starts with an X (have a go at this: name five words that start with X without googling*).

And then, if I think we’ve got time for a story, I might go for the famous and much-maligned element number 33: arsenic (As).  After all, if it weren’t one of the world’s most famous poisons you’d have to love it just for having the word ‘arse’ in its name.

arsenic poison bottle

So, a little background. It’s the 20th most common element in the Earth’s crust, and is actually one of the oldest known elements. It was officially first documented around 1250 by a Dominican friar called Alvertus Magnus but it’s been used for more than 3000 years, going back as far as the bronze age when it was added to bronze to make it harder. It’s a metalloid, which means it’s neither quite metal nor non-metal, and these days its most important use is in the electronics industry.

There are many, many interesting stories associated with arsenic. One of my personal favourites, if that’s the right word, is the story of the Bradford Sweets Poisoning. Back in 1858 a Bradford confectioner known as ‘Humbug Billy’ was buying his mint humbugs from another local character called Joeseph Neal. At the time, sugar was expensive so Neal was in the habit of cutting it with something called ‘daft’, a mysterious substance that could contain anything from limestone to plaster of Paris. Neal sent his lodger to the local pharmacy to collect the daft. The druggist was ill, and somehow or other his assistant managed to sell Neal’s lodger 12 pounds of arsenic trioxide (you might imagine this was an expensive error, but arsenic was actually surprisingly cheap: half an ounce cost about the same as a cup of tea).

The mistake went undetected, despite the sweetmaker who worked for Neal suffering symptoms of illness during the sweet-making process, and despite the resulting humbugs looking so different from normal that Humbug Billy managed to buy them from Neal at a discount. Humbug Billy himself promptly became ill after eating the sweets, but nevertheless still sold 5 pounds of them from his market stall that day. Subsequently about 20 people died and a further 200 became ill. To start with the deaths were blamed on cholera, common at the time, but soon they were traced to the sweet stall. Later analysis showed that each humbug contained enough arsenic to kill two people.

This tragic tale led to The Pharmacy Act 1868 and the requirement for proper record keeping by pharmacists. Ultimately it also led to legislation preventing the adulteration of foodstuffs, such as for example, oh I don’t know, sneaking horse into something labelled beef.

Historically arsenic was also used in dyes and pigments, perhaps most famously Scheele’s Green – also known as copper arsenite and invented by Carl Wilhelm Scheele in 1775 – produced a wonderful green colour that was used to dye wallpaper, fabrics, added to paints, children’s toys and even sweets. Many poisonings in Victorian times were linked to toxic home furnishings and clothing. In fact, this probably explains the superstition that green is an unlucky colour, especially for children’s furnishings and clothes. Arsenic poisoning being very unlucky indeed. Next time you’re near a baby store, have a look: even today (arsenic pigments now long defunct, thank goodness) you still don’t see that many green things.

One of the most famous people to die from arsenic poisoning was probably Napoleon. Originally thought to have been deliberately poisoned, analysis of his hair samples in 2008 demonstrated that his exposure had been long-term rather than sudden, and was probably due to the lovely green wallpaper and paint decorating the room in which he’d been confined.

Then there’s George III, the famously ‘mad King George’. His episodes of madness and physical symptoms were linked to the disease porphyria, and 2004 studies of samples of his hair also found very high levels of arsenic which may well have triggered his symptoms. Ironically, he may have been exposed to arsenic as part of his medical treatment.

In fact historically arsenic was used to treat many medical complaints. It’s even been used as an aphrodisiac, thanks to the fact that small doses stimulate blood flow. In 1851 it was reported that peasants in Styria, a remote region in Austria, were in the habit of swallowing solid lumps of the stuff that, fortunately, passed through their digestive system relatively intact. However they absorbed just enough to given the women a rosy glow and the men an increased libido – resulting in something of a population boom. Upon hearing about this British manufacturers immediately began selling arsenic-containing beauty products, including soap and skin treatments, with predictably tragic results.

Thanks to its toxicity arsenic is used in pesticides, herbicides and insecticides, although these uses are gradually being phased out. Despite being notoriously poisonous to most organisms, there are interestingly some species of bacteria whose metabolism relies on arsenic. Arsenic turns up naturally in groundwater and is absorbed by plants such as rice, as well turning up, in the form of arsenobetaine, in mushrooms and fish. Don’t worry though, this particular arsenic compound is virtually non-toxic.

Today gallium arsenide, with the brilliant chemical formula GaAs, is one of biggest uses of arsenic. It’s a semiconductor, used in the manufacture of many electronic devices, including solar cells. Its electronic properties are, in some ways, superior to silicon so despite its inherent dangers its important stuff.

So it definitely has one of the most fascinating histories of any of the elements, and I’ve only mentioned a tiny number of the many, many arsenic-related stories out there.  From the bronze age to the computer age, arsenic has been with us, both friend and foe, and will be with us for a lot longer yet.

So, what’s your favourite element? Tell me and maybe I’ll write about it in a future post!

——

* betcha said xenon (of course), xylophone, xi and xu if you play Scrabble, x-ray and maybe xylem. Am I right?