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Chemical du jour: how bad is BPA, really?

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BPA is an additive in many plastics

When I was writing my summary of 2017 I said that there would, very probably, be some sort of food health scare at the start of 2018. It’s the natural order of things: first we eat and drink the calorie requirement of a small blue whale over Christmas and New Year, and then, lo, we must be made to suffer the guilt in January. By Easter, of course, it’s all forgotten and we can cheerfully stuff ourselves with chocolate eggs.

Last year it was crispy potatoes, and the year before that it was something ridiculous about sugar in ketchup causing cancer (it’s the same sugar that’s in everything, why ketchup? Why?). This year, though, it seems that the nasty chemical of the day is not something that’s in our food so much as around it.

Because this year the villain of the piece appears to be BPA, otherwise known as Bisphenol A or, to give it its IUPAC name, 4,4′-(propane-2,2-diyl)diphenol.

BPA is an additive in plastics. At the end of last year an excellent documentary aired on the BBC called Blue Planet II, all about our planet’s oceans. It featured amazing, jaw-dropping footage of wildlife. It also featured some extremely shocking images of plastic waste, and the harm it causes.

Plastic waste is a serious problem

Plastic waste, particularly plastic waste which is improperly disposed of and consequently ends up in the wrong place, is indisputably something that needs to be addressed. But this highlighting of the plastic waste problem had an unintended consequence: where was the story going to go? Everyone is writing about how plastic is bad, went (I imagine) editorial meetings in offices around the country – find me a story showing that plastic is even WORSE than we thought!

Really, it was inevitable that a ‘not only is plastic bad for the environment, but it’s bad for you, too!’ theme was going to emerge. It started, sort of, with a headline in The Sun newspaper: “Shopping receipts could ‘increase your cancer risk’ – as 93% contain dangerous chemicals also linked to infertility. Shopping receipts are, of course, not made of plastic – but the article’s sub-heading stated that “BPA is used to make plastics”, so the implication was clear enough.

Then the rather confusing: “Plastic chemical linked to male infertility in majority of teenagers, study suggests” appeared in The Telegraph (more on this in a bit), and the whole thing exploded. Search for BPA in Google News now and there is everything from “5 Ways to Reduce Your Exposure to Toxic BPA” to “gender-bending chemicals found in plastic and linked to breast and prostate cancer are found in 86% of teenagers”.

Yikes. It’s all quite scary. It’s true that right now you can’t really avoid plastic. Look around you and it’s likely that you’ll immediately see lots of plastic objects, and that’s before you even try to consider all the everyday things which have plastic coatings that aren’t immediately obvious. If you have young children, you’re probably drowning in plastic toys, cups, plates and bottles. We’re pretty much touching plastic continually throughout our day. How concerned should we be?

As the Hitchiker’s Guide to the Galaxy says, Don’t Panic. Plastic (like planet Earth in the Guide) can probably be summed up as mostly harmless, at least from a BPA point of view if not an environmental one.

BPA is a rather pleasingly symmetrical molecule with two phenol groups. (A big model of this would make a wonderfully ironic pair of sunglasses, wouldn’t it?) It was first synthesized by the Russian chemist Alexander Dianin in the late 19th century. It’s made by reacting acetone – which is where the “A” in the name comes from – with two phenol molecules. It’s actually a very simple reaction, although the product does need to be carefully purified, since large amounts of phenol are used to ensure a good yield.

It’s been used commercially since the fifties, and millions of tonnes of BPA are now produced worldwide each year. BPA is used to make plastics which are clear and tough – two characteristics which are often valued, especially for things like waterproof coatings, bottles and food containers.

The concern is that BPA is an endocrine disruptor, meaning that it interferes with hormone systems. In particular, it’s a known xenoestrogen, in other words it mimics the female hormone estrogen. Animal studies have suggested possible links to certain cancers, infertility, neurological problems and other diseases. A lot of the work is fairly small-scale and, as I’ve mentioned, focused on animal studies (rather than looking directly at effects in humans). Where humans have been studied it’s usually been populations that are exposed to especially high BPA levels (epoxy resin painters, for example). Still, it builds up into quite a damning picture.

BPA has been banned from baby bottles in many countries, including the USA and Europe

Of course, we don’t normally eat plastic, but BPA can leach from the plastic into the food or drink that’s in the plastic, and much more so if the plastic is heated. Because of these concerns, BPA has been banned from baby bottles (which tend to be heated, both for sterilisation and to warm the milk) in several countries, including the whole of Europe, for some years now. “BPA free” labels are a fairly common sight on baby products these days. BPA might also get onto our skin from, for example, those thermal paper receipts The Sun article mentioned, and then into our mouths when we eat. Our bodies break down and excrete the chemical fairly quickly, in as little as 6 hours, but because it’s so common in our environment most of us are continually meeting new sources of it.

How much are we getting, though? This is a critical question, because as I’m forever saying, the dose makes the poison. Arsenic is a deadly poison at high levels, but most of us – were we to undergo some sort of very sensitive test – would probably find we have traces of it in our systems, because it’s a naturally-occuring mineral. It’s nothing to worry about, unless for some reason the levels become too high.

When it comes to BPA, different countries have different guidelines. The European Food Safety Authority recommended in January 2015 that the TDI (tolerable daily intake) should be reduced from 50 to 4 µg/kg body weight/day (there are plans for a new assessment in 2018, so it might change again). For a 75 kg adult, that translates to about 0.0003 g per day. A USA Federal Drug and Administration document from 2014 suggests a NOAEL (no-observed-adverse-effect-level) of 5 mg/kg bw/day, which translates to 0.375 g per day for the same 75 kg adult. NOAEL values are usually much higher than TDIs, so these two figures aren’t as incompatible as they might appear. Tolerable daily intake values tend to have a lot of additional “just in case” tossed into them – being rather more guidance than science.

The European Food Standards Authority published a detailed review of the evidence in 2015 (click for a summary)

So, how much BPA are we exposed to? I’m going to stick to Europe, because that’s where I’m based (for now…), and trying to look at all the different countries is horribly complicated. Besides, EFSA produced a really helpful executive summary of their findings in 2015, which makes it much easier to find the pertinent information.

The key points are these: most of our exposure comes from food. Infants, children and adolescents have the highest dietary exposures to BPA, probably because they eat and drink more per kilogram of body weight. The estimated average was 0.375 µg/kg bw per day.  For adult women the estimated average was 0.132 µg/kg bw per day, and for men it was 0.126 µg/kg bw per day.

When it came to thermal paper and other non-dietary exposure (mostly from dust, toys and cosmetics), the numbers were smaller, but the panel admitted there was a fair bit of uncertainty here. The total exposure from all sources was somewhere in the region of 1 µg/kg bw per day for all the age groups, with adolescents and young children edging more toward values of 1.5 µg/kg bw per day (this will be important in a minute).

Note that all of these numbers are significantly less than the, conservative, tolerable daily intake value of 4 µg/kg bw per day recommended by EFSA.

Here’s the important bit: the panel concluded that there is “no health concern for BPA at the estimated levels of exposure” as far as diet goes. They also said that this applied “to prenatally exposed children” (in other words, one less thing for pregnant women to worry about).

When it came to total exposure, i.e. diet and exposure from other sources such as thermal paper they concluded that “the health concern for BPA is low at the estimated levels of exposure”.

The factsheet that was published alongside the full document summarises the results as follows: “BPA poses no health risk to consumers because current exposure to the chemical is too low to cause harm.”

Like I said: Don’t Panic.

What about those frankly quite terrifying headlines? Well, firstly The Sun article was based on some work conducted on a grand total of 208 receipts collected in Southeast Michigan in the USA from only 39 unique business locations. That’s a pretty small sample and not, I’d suggest, perhaps terribly relevant to the readership of a British newspaper. Worse, the actual levels of BPA weren’t measured in the large majority of samples – they only tested to see if it was there, not how much was there. There was nothing conclusive at all to suggest that the levels in the receipts might be enough to “increase your cancer risk”. All in all, it was pretty meaningless. We already knew there was BPA in thermal receipt paper – no one was hiding that information (it’s literally in the second paragraph of the Wikipedia page on BPA).

The Telegraph article, and the many others it appeared to spawn, also weren’t based on especially rigorous work and, worse, totally misrepresented the findings in any case. Firstly, let’s consider that headline: “Plastic chemical linked to male infertility in majority of teenagers, study suggests”. What does that mean? Are they suggesting that teenagers are displaying infertility? No, of course not. They didn’t want to put “BPA” in the headline because that, apparently, would be too confusing for their readers. So instead they’ve replaced “BPA” with “plastic chemical linked to male infertility”, which is so much more straightforward, isn’t it?

And they don’t mean it’s linked to infertility in the majority of teenagers, they mean it’s linked to infertility and it’s in the majority of teenager’s bodies. I do appreciate that journalists rarely write headlines – this isn’t a criticism of the poor writer who turned in perfectly good copy – but that is confusing and misleading headline-writing of the highest order. Ugh.

Plus, as I commented back there, that wasn’t even the conclusion of the study, which was actually an experiment carried out by students under the supervision of a local university. The key finding was not that, horror, teenagers have BPA in their bodies. The researchers assumed that almost all of the teenagers would have BPA in their bodies – as the EFSA report showed, most people do. No, the conclusion was actually that the teenagers – 94 of them – had been unable to significantly reduce their levels of BPA by changing their diet and lifestyle. Although the paper admits the conditions weren’t well-controlled. Basically, they asked a group of 17-19 year-olds to avoid plastic, and worked on the basis that their account of doing so was accurate.

And how much did the teenagers have in their samples? The average was 1.22 ng/ml, in urine samples (ng = nanogram). Now, even if we assume that these levels apply to all human tissue (which they almost certainly don’t) and that therefore the students had roughly 1.22 ng per gram of body weight, that only translates to, very approximately, 1.22 micrograms (µg) per kilogram of body weight.

Wait a second… what did EFSA say again…. ah yes, they estimated total exposures of 1.449 µg/kg bw per day for adolescents.

Sooooo basically a very similar value, then? And the EFSA, after looking at multiple studies in painstaking detail, concluded that “BPA poses no health risk to consumers”.

Is this grounds for multiple hysterical, fear-mongering headlines? I really don’t think it is.

It is interesting that the teenagers were unable to reduce their BPA levels. Because it’s broken down and excreted quite quickly by the body, you might expect that reducing exposure would have a bigger effect – but really all we can say here is that this needs to be repeated with far more tightly-controlled conditions. Who knows what the students did, and didn’t, actually handle and eat. Perhaps their school environment contains high levels of BPA in dust for some reason (new buildings or equipment, maybe?), and so it was virtually impossible to avoid. Who knows.

In summary, despite the scary headlines there really is no need to worry too much about BPA from plastics or receipts. It may be worth avoiding heating plastic, since we know that increases the amound of BPA that makes its way into food – although it’s important to stress that there’s no evidence that microwaving plastic containers causes levels to be above safe limits. Still, if you wanted to be cautious you could choose to put food into a ceramic or glass bowl, covered with a plate rather than clingfilm. It’ll save you money on your clingfilm bills anyway, and it means less plastic waste, which is no bad thing.

Roll on Easter…

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Hydrogen peroxide: another deadly alternative?

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I’m sure most people have heard of hydrogen peroxide. It’s used as a disinfectant and, even if you’ve never used it for that, you probably at least know that it’s used to bleach hair. It’s where the phrase “peroxide blonde” comes from, after all. Hydrogen peroxide, and its formula, is so famous that there’s an old chemistry joke about it:

(I have no idea who to credit for the original drawing – if it’s you, leave me a message.)

To save you squinting at the text, it goes like this:
Two men walk into a bar. The first man says, “I’ll have some H2O.”
The second man says, “I’ll have some H2O, too.”
The barman brings the drinks. The second man dies horribly.

Now I think about it, it’s not a terribly funny joke.

Hydrogen peroxide has an extra oxygen atom in the middle.

Never mind. You get the idea. H2O2 (“H2O, too”) is the formula for hydrogen peroxide. Very similar to water’s formula, except with an extra oxygen atom in the middle. In fact, naturopaths – purveyors of alternative therapies – often refer to hydrogen peroxide as “water with extra oxygen”. But this is really misleading because, to torture a metaphor, that extra oxygen makes hydrogen peroxide the piranha to water’s goldfish.

Water, as we know, is pretty innocuous. You should try not to inhale it obviously, or drink more than about six litres in one go, but otherwise, its pretty harmless. Hydrogen peroxide, on the other hand, not so much. The molecule breaks apart easily, releasing oxygen. That makes it a strong oxidising agent. It works as a disinfectant because it basically blasts cells to pieces. It bleaches hair because it breaks down pigments in the hair shaft. And, as medical students will tell you, it’s also really good at cleaning up blood stains – because it oxidises the iron in haemoglobin to Fe3+, which is a pale yellow colour*.

Dilute hydrogen peroxide is readily available.

In its dilute form, hydrogen peroxide is a mild antiseptic. Three percent and even slightly more concentrated solutions are still readily available in high-street pharmacies. However, even these very dilute solutions can cause skin and eye irritation, and prolonged skin contact is not recommended. The trouble is, while it does destroy microbes, it also destroys healthy cells. There’s been a move away from using hydrogen peroxide for this reason, although it is still a popular “home” remedy.

More concentrated** solutions are potentially very dangerous, causing severe skin burns. Hydrogen peroxide is also well-known for its tendency to react violently with other chemicals, meaning that it must be stored, and handled, very carefully.

All of which makes the idea of injecting into someone’s veins particularly horrific.

But this is exactly what some naturopaths are recommending, and even doing. The idea seems to have arisen because hydrogen peroxide is known to damage cancer cells. But so will a lot of other dangerous substances – it doesn’t mean it’s a good idea to inject them. Hydrogen peroxide is produced by certain immune cells in the body, but only in a very controlled and contained way. This is definitely a case where more isn’t necessarily better.

The use of intravenous hydrogen peroxide appears to have begun in America, but it may be spreading to the UK. The website yestolife.org.uk, which claims to empower people with cancer to “make informed decisions”, states “The most common form of hydrogen peroxide therapy used by doctors calls for small amounts of 30% reagent grade hydrogen peroxide added to purified water and administered as an intravenous drip.”

30% hydrogen peroxide is really hazardous stuff. It’s terrifying that this is being recommended to vulnerable patients.

Other sites recommend inhaling or swallowing hydrogen peroxide solutions, both of which are also potentially extremely dangerous.

If anyone ever suggests a hydrogen peroxide IV, run very fast in the other direction.

In 2004 a woman called Katherine Bibeau died after receiving intravenous hydrogen peroxide treatment from James Shortt, a man from South Carolina who called himself a “longevity physician”. According to the autopsy report she died from systemic shock and DIC – the formation of blood clots in blood vessels throughout the body. When her body arrived at the morgue, she was covered in purple-black bruises.

Do I need to state the obvious? If anyone suggests injecting this stuff, run. Run very fast, in the other direction. Likewise if they suggest drinking it. It’s a really stupid idea, one that could quite literally kill you.

* As anyone who’s ever studied chemistry anywhere in my vicinity will tell you, “iron three is yellow, like wee.”

** The concentration of hydrogen peroxide is usually described in one of two ways: percentage and “vol”. Percentage works as you might expect, but vol is a little different. It came about for practical, historical reasons. As Prof. Poliakoff comments in this video, hydrogen peroxide is prone to going “flat” – leave it in the bottle for long enough and it gradually decomposes until what you actually have is a bottle of ordinary water. Particularly in the days before refrigeration (keeping it cold slows down the decomposition) a bottle might be labelled 20%, but actually contain considerably less hydrogen peroxide.

What to do? The answer was quite simple: take, say, 1 ml of hydrogen peroxide, add something which causes it to decompose really, really fast (lots of things will do this: potassium permanganate, potassium iodide, yeast, even liver) and measure the volume of oxygen given off. If your 1 ml of hydrogen peroxide produces 10 ml of oxygen, it’s 10 vol. If it produces 20, it’s 20 vol. And so on. Simple. 3% hydrogen peroxide, for the record, is about 10 vol***. Do not mix up these numbers.

*** Naturally, there are mole calculations to go with this. Of course there are. For A-level Chemists, here’s the maths (everyone else can tune out; I’m adding this little footnote because I found this information strangely hard to find):

Hydrogen peroxide decomposes as shown in this equation:
2H2O2 –> 2H2O + O2

Let’s imagine we decompose 1 ml of hydrogen peroxide and obtain 10 mls of oxygen.

Assuming the oxygen gas occupies 24 dm3 (litres), or 24000 mls, at standard temperature and pressure, 10 mls of oxygen is 10 / 24000 = 0.0004167 moles. But, according to the equation, we need two molecules of hydrogen peroxide to make one molecule of oxygen, so we need to multiply this number by two, giving us 0.0008333 moles.

To get the concentration of the hydrogen peroxide in the more familar (to chemists, anyway) mol dm-3, just divide that number of moles by the volume of hydrogen peroxide. In other words:

0.0008333 mols / 0.001 dm3 = 0.833 mol dm-3

If you really want to convert this into a percentage by mass (you can see why people stick with “vol” now, right?), then:

0.833 mol (in the litre of water) x 34 g mol-1 (the molecular mass of H2O2)
= 28.32 g (in 1000 g of water)

Finally, (28.32 / 1000) x 100 = 2.8% or, rounding up, 3%

In summary (phew):
10 vol hydrogen peroxide = 0.83 mol dm-3 = 3%

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What IS a chemical?

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a_chemistry_teacher_explaining_an_experiment_8d41253v

You at the back there! Get your nose out of that dictionary and pay attention!

What do we mean when we use the word “chemical”? It seems like a simple enough question, but is it, really? I write about chemicals all the time – in fact my last WhatCulture article was about just that – and I’ve mentioned lots of different definitions before. But I’ll be honest, some of them have bothered me.

I don’t often like the definitions you find in dictionaries. Lexicography and chemistry don’t seem to be common bedfellows, and dictionary compilers haven’t, generally speaking, spent their formative years being incessantly nagged by weary chemistry teachers about their choice of vocabulary.

For example, in the Cambridge Dictionary we find:
“any basic substance that is used in or produced by a reaction involving changes to atoms or molecules.”

Hm. Firstly, “basic” has a specific meaning in chemistry. Obviously the definition doesn’t mean to imply that acids aren’t chemicals, but it sort of accidentally does. Then there’s the implication that a chemical reaction has to be involved. So inert substances aren’t chemicals? Admittedly, “used in” doesn’t necessarily imply reacts – it could be some sort of inert solvent, say – but, again, it’s bothersome. Finally, “atoms or molecules”. Ionic substances not chemicals either, then?

Yes, it’s picky, but chemists are picky. Be glad that we are. A misplaced word, or even letter, on a label could have serious consequences. Trust me, you do not want to mix up the methanol with the ethanol if you’re planning cocktails. Similarly, fluorine is a whole other kettle of piranhas compared to fluoride ions. This stuff, excuse the pun, matters.

Dictionary definitions have their problems.

Dictionary definitions have their problems.

Let’s look at some more definitions (of the word as a noun):

The Free Dictionary tells us that a chemical is:
“A substance with a distinct molecular composition that is produced by or used in a chemical process.”

Merriam Webster says:
“of, relating to, used in, or produced by chemistry or the phenomena of chemistry <chemical reactions>”

And Dictionary.com goes with the simple:
“a substance produced by or used in a chemical process.”

That idea that a chemical reaction must be involved somehow seems to be pervasive. It’s understandable, since that’s the way the word is mostly used, but it’s not really right. Helium, after all, is still very much a chemical, despite being stubbornly unreactive.

Possibly the best of the bunch is found in the Oxford Living Dictionary:
“A distinct compound or substance, especially one which has been artificially prepared or purified.”

Not bad. Well done Oxford. No mention of chemical reactions here – it’s just a substance. We do most often think of chemicals as things which have been “prepared” somehow. Which is fair enough, although it can lead to trouble. In particular, ridiculous references to “chemical-free” which actually mean “this alternative stuff is naturally-occurring.” (Except of course it often isn’t: see this article about baby wipes.) The implication, of course, is that thing in question is safe(r), but there are lots and lots of very nasty chemicals in nature: natural does not mean safe.

You keep using that word. I do not think it means what you think it means.

Sometimes people will go the other way and say “everything is chemicals.” We know what this means, but it has its problems, too. Light isn’t a chemical. Sound isn’t a chemical. All right, those are forms of energy. What about neutrinos, then? Or a single proton? Or a single atom? Or, going the other way, some complicated bit of living (or once living) material? In one debate about this someone suggested to me that a “chemical was anything you could put in a jar,” at which point I pedantically said, “I keep coffee in a jar. Is that a chemical?” Obviously there are chemicals in coffee, it works from the “everything is chemicals” perspective, but it’s a single substance that’s not a chemical.

Language is annoying. This is why chemists like symbols and numbers so much.

Anyway, what have we learned? Firstly, something doesn’t necessarily have to be part of a chemical reaction to be a chemical. Secondly, we need to include the idea that it’s something with a defined composition (rather than a complex, variable mixture, like coffee), thirdly that chemical implies matter – light, sound etc don’t count, and fourthly that it also implies a certain quantity of stuff (we probably wouldn’t think of a single atom as a chemical, but collect a bunch together into a sample of gas and we probably would).

So with all that in mind, I think I shall go with:

So what IS a chemical?

A chemical is…

(Drum roll please….)

Any substance made of atoms, molecules and/or ions which has a fixed composition.

I’m not entirely convinced this is perfect, but I think it more or less works.

If you have a better idea, please do comment and let me know!

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Chemical paranoia: are they really going to get you?

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chemicals1There are many warnings about nasty chemicals on the internet. “Ooh, chemicals are really BAD for you!!” type these paranoid types, on their computer made largely of polymers, with a screen containing liquid crystals, running on a lithium ion battery. “We’re being POISONED by all this stuff They’re putting into our food and water!!!” They cry, whilst drinking coffee that (naturally) contains caffeine, chlorogenic acids and umpteen other chemicals, having earlier swallowed some diphenhydramine for their many allergies and popping paracetamol pills for their terrible stress headache caused by all those capital letters and exclamation marks.

A quick glance at Snopes’ wonderful ‘Toxin du jour‘ page reveals a long list of stories which Snopes, the original home of internet urban legends, has cheerfully debunked, from the notion that aspartame is responsible for a cancer epidemic (it’s not), that microwaving plastic containers leaches dangerous chemicals into the food (it doesn’t) and the bizarre story of a mixture of certain type of baby formula and dog food causing a todler’s stomach to explode (do I need to state the obvious?)

Of course in writing this I fear I’m preaching to the converted, since people that forward on emails warning of the risk of deadly poisoning from re-using plastic drinking water bottles and the like never seem to be the sort of people to actually check their facts by, say, taking three seconds to type anything at all into a well-known search engine. And I therefore suspect they wouldn’t be reading this blog, it being dangerously factual and all. But for the sake of thoroughness, chemicals are all around us. The dictionary definition is “something with a distinct chemical composition that is produced by, or used in, a chemical process”. Most things are used in a chemical process somewhere, including such mundanities as water, oxygen and nitrogen. The only way anyone could avoid chemicals all together would be to lock themselves into a hermetically sealed chamber and pump all the air out. And that’s far from being a route to a long and healthy life.

“Ah, but,” the fearful cry, “we don’t mean NATURAL chemicals. We mean ARTIFICIAL ones. The ones chemists cook up in laboratories. Not nice natural things!”

Ah yes. Lovely, naturally-occurring chemicals. Like nicotine (the deadly nerve poison found in tobacco), lily of the valley (contains a high enough concentration of cardiac glycosides that even the water the flowers are placed in could be dangerously toxic), carbon monoxide (deadly by-product of the incomplete combustion of any carbon-based fuel, including all the ones you might be using in your house, such as wood, or coal, or gas) and botulinum toxin (the most acutely toxic substance known, naturally produced by the bacterium clostridium botulinum).

In fact, sometimes the synthetically produced is safer: for example salicylic acid (naturally-occurring in willow tree bark), while not particularly deadly is certainly a lot less friendly to the human digestive system than its chemically-modified cousin acetylsalicylic acid, otherwise known as aspirin.

And then there are food additives. They’re bad for you, right? They cause cancer, irritable bowl syndrome, hyperactivity, asthma, headaches, obesity, bad skin, bloating, unmanageable hair, purple rashes, gymphobia and notlikeingmondayitis, amongst other things. All of them*. You should definitely always buy foods that don’t have additives in. Everyone knows that.

Actually, no. In fact a lot of food additives keep us safe. Remember that botulinum toxin I mentioned up there? The most acutely toxic substance known? The bacterium that produces it grows in meat products. In fact, the German medical writer Justinus Kerner called it a “sausage poison” for that very reason. Why don’t people die from botulism more often? Because sodium nitrite (E250) is regularly added to meat products, and it does a great job of preventing clostridium botulinum from growing. It’s true that nitrites aren’t entirely controversy-free (in particular they’ve been linked to bowel cancer) but, and it’s a big but, the risk from botulism is much, much bigger than the small, theoretical, increase in your chances of developing cancer. Eating a botulism-laden sausage will kill you. Quickly. If you’re going to eat sausages at all, E250 is a good thing.

Many, many food additives are from entirely natural sources. Take the emulsifier lecithin (E322). It’s usually extracted from eggs or soy beans. Entirely homemade mayonnaise makes use of this chemical (whether knowingly or not) to keep the fat and water in the recipe from separating into layers. Ascorbic acid (E300) is used as an acidity-regulator and anti-oxidant, and its other name is good old vitamin C. Beeswax (E901) is routinely used as a glazing agent, espeically on apples, and there are a whole raft of colourings that are totally natural in origin, including caramel (E150a), Riboflavin (vitamin B2, E101) and beetroot red (E162). And by the way, those scary E numbers? The E just means they’re substances which have been approved for use within the European Union. In other words, they’ve been tested and shown to be safe. You could argue that those E’s are actually a very good thing. Who knew?

Then of course there’s E621, monosodium glutamate, used as a flavour enhancer (it produces the meaty flavour, umami). I feel sorry for poor old MSG, it gets a bad press. Blamed for everything from migraines to obesity to asthma (really this time). It’s been used for more than 100 years to season food, and is just the sodium salt of glutamic acid, one of the most abundant naturally-occurring amino acids. The MSG that’s added to food these days is mostly made by bacterial fermentation, not unlike yoghurt or vinegar. But glutamic acid turns up everywhere, or at least everywhere there’s protein, and therefore so do its salts. Lots of foods are naturally high in glutamate, including cheese, tomatoes, mushrooms and walnuts. It’s the same stuff, just with less sodium. So it’s safe to say that you can cheerfully ignore anyone who tells you that MSG is horribly bad for you, especially if they’re munching on a mushroom. Not to suggest that you should live off processed foods, of course, but you may do better to worry about the salt, sugar and fat content first.

In fact a lot of synthetic chemicals make our lives easier. Where would we be without medicines for example? (Not to be too blunt, probably dead.) Without the concoction that is toothpaste, most of us wouldn’t have our own teeth. Without chlorine in water we’d probably have died of typhoid or cholera (people arguing against it usually conveniently forget about those two, which used to kill by the tens of thousands). Just have a look around at all the plastic you use, and imagine for a second what life would be like without it: no soft contact lenses, no mobile phones, computers or TVs, no waterproof jacket or shoes, no biros, no packaging to keep food fresh and protected, no nylon or other synthetic fabrics… the list goes on.

So next time someone talks disparagingly about all those ‘chemicals’, ask them about all the ones they’re using right now. Or send them to Snopes. Or order that hermetically sealed, vacuum-pumped chamber. At least it’d be quiet.

——–

After I published this post, I came across this absolutely brilliant pic on Twitter: https://twitter.com/drandyrobertson/status/339991142793883648/photo/1
Fantastic!

*Given that I earlier claimed to be factual, I should admit that I may have made some of those up.