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Vitriolic attacks

sulfuric acidIn the Sherlock Holmes story, The Case of the Illustrious Client, a former paramour seeks revenge on the dastardly Baron Adelbert Gruner by splashing the Baron’s face with sulphuric acid, which at the time was commonly known as vitriol.  The effect was accurately described by Conan Doyle, which is not surprising, given that the author of the Sherlock Holmes stories was a physician: “The vitriol was eating into it everywhere and dripping from the ears and the chin. One eye was already white and glazed. The other was red and inflamed. The features which I had admired a few minutes before were now like some beautiful painting over which the artist has passed a wet and foul sponge. They were blurred, discoloured, inhuman, terrible.”  Such vitriolic attacks are terrible indeed.

Credit for the discovery of sulphuric acid is usually attributed to Jabir ibn Hayyan, an Arabian alchemist of the eight century.  Our term “gibberish” supposedly derives from his English name Geber, in reference to the alchemists’ use of secret codes that to others were incomprehensible, or “gibberish.”  But it seems Jabir’s experiments with hydrated sulfate salts of iron and copper were recorded well enough for him to be credited with the discovery of vitriol.  The term “hydrated” refers to the inclusion of water in the crystal structure of these substances.  Hydrated iron sulphate or copper sulphate decompose on heating to yield sulphur trioxide and water, which then combine to yield sulphuric acid, or vitriol.  Vitreus is the Latin word for glass, and since crystals of sulphate salts have a glass-like appearance, “oil of vitriol” became a reasonable name for the acid that was derived from the heat treatment of these salts.  Indeed, copper sulphate still has the common name blue vitriol, iron sulphate is green vitriol and cobalt sulphate is red vitriol.

Sulphuric acid is an extremely corrosive substance and can cause permanent disfigurement when splashed on the skin.  Unfortunately such vitriolic attacks are not limited to fictional detective stories, they happen in real life.  An attack by extremists on girls on their way to school in Afghanistan is a recent horrific example.  Believing that girls would be polluted by education, they carried out an attack leaving some of the students scarred for life, both figuratively and literally.  Used in this way, sulphuric acid is a terrible chemical weapon.  But it is also the most important industrial chemical in the world, without which the steel, fertilizer and plastics industries would be crippled.  There are no safe or dangerous chemicals, there are only safe and dangerous ways to use chemicals.

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Streptomycin and Blueberries

blueberriesA story is blazing around the blogosphere about a ten year old girl having an anaphylactic reaction to a blueberry pie. Physicians supposedly traced the reaction to streptomycin used as a pesticide on the blueberries. The account is spreading like wildfire with warnings about how an “antibiotic reside in food may cause severe allergies.” The reference is to a paper in the September issue of Annals of Allergy, Asthma and Immunology, a reputable publication. But there is a problem. The September issue is not yet out. So how do we know about the case? Because the Journal has put out a press release hyping the story. Scientific journals, just like any other publication, vie for readership and subscriptions, so they do seek attention. But here we are talking about a story that has some questionable features that cannot be checked because the actual paper is not yet available.

So what are these questionable features? First of all, the use of antibiotics as pesticides is rare. In Canada, streptomycin is registered only for use against “fire blight,” a destructive bacterial disease that can strike pear and apple trees. It cannot be used on blueberries. In the U.S. it may also be used on tomatoes and is even allowed in organic agriculture because it comes from a natural source, the bacterium Streptomyces griseus. The use of streptomycin is uncommon. Any suggestion that antibiotics are widely used as pesticides is simply wrong. The press release states that “as far as we know, this is the first report that links an allergic reaction to fruits treated with antibiotic pesticides.” Since streptomycin has been allowed for decades, and this is the first time a problem has cropped up, we are not looking at a highly significant problem. If indeed the problem was streptomycin.

We’ll have to wait to see what the case report actually says about how the reaction was linked to the antibiotic. Streptomycin breaks down quickly in the environment and the prescribed pre-harvest interval for its use is long so it would not be expected to show up in any marketed food. It is worth mentioning that at one time or another traces of fifty two pesticides have been detected on blueberries, but never streptomycin. For now, the story is more along the lines of the impropriety of an alarmist press release before the details of the actual study are made available.

 

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A nail polish to detect drugs?

detect drugsThe press went crazy jumping all over a report that four North Carolina students invented a nail polish to detect “date rape” drugs. Just dip a finger into a drink, and watch for a colour change that is indicative of the beverage having been doctored with rohypnol, Xanax or gamma hydroxybutyrate, the classic date rape drugs. At least so goes the story.. Actually, the nail polish doesn’t yet exist, it is just a concept. It is, however, a legitimate idea, given that test strips, coasters, straws and even glasses that change colour in response to the presence of certain drugs do exist.

The chemistry here is fascinating but very complex. It is based on a polymer which is cross linked after being treated with the drug that is to be eventually detected. The drug forges a space in the polymer matrix according to its molecular shape. It is then washed out leaving a cavity in the shape of the drug molecule. The same drug is then coupled to a dye and is added to occupy the spaces that have been vacated. When the polymer, which in theory could be incorporated into nail polish, is then dipped into a beverage, should any of the same drug be present, it will displace some of the the embedded molecules which after being bumped out release the dye that was attached.

Just how well the technology works still has not been properly established. There are many substances such as juices or milk that can interfere with the reaction.Furthermore there is a whole host of other potential date rape drugs like ketamine, zolpidem, barbiturates, chloral hydrate, opiods and phencyclidine that would not be detected. And of course the most widely used date rape drug is alcohol. Then there is also the issue that such products suggest that it is a potential victim’s responsibility to detect the presence of a drug. As is far too common, press reports have been far too zealous in hyping this “invention.”

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You Asked: Why is Canada banning citronella-based insect repellants?

citronellaHealth Canada is set to ban topical mosquito repellants that contain oil of citronella. The oil contains methyleugenol, a compound that has caused liver tumours in rats fed in large doses, but this really has no relevance to topical application by humans While there is no evidence of harm from any topical application, other than the rare allergic reaction, no formal studies of safety have been carried out. In this case Health Canada seems to be applying the letter of the law. Insecticides, whether natural or synthetic, are regulated by Canada’s Pest Management Regulatory Agency (PMRA) which is distinct from the Natural Products Directorate. The law is that any pesticide has to be backed up by appropriate safety studies and the requirements here are far more stringent than those for natural products. The required safety studies for citronella have never been carried out because the product is not patentable and no company wants to invest the necessary funds.

Contrary to arguments voiced by some conspiracy theorists, Big Pharma, producers of DEET, is not behind the ban. Citronella isn’t a significant competitor for the simple reason that it doesn’t work very well. Basically, what Health Canada is saying to citronella repellant producers is, “hey, you are claiming your product is an insecticide, then it has to be regulated as one and the same rules apply as for any other insecticide.” And since the safety studies are not available, the law says citronella cannot be sold as an insecticide.

What is disturbing here is that Health Canada has gone after what almost certainly is an innocuous product while allowing a nonsensical homeopathic mosquito repellant, Mozi-Q, to be sold, even furnishing it with a homeopathic drug identification number. This absurdity comes about because homeopathic products fall under different regulations. There is no requirement for safety or efficacy. A ridiculous situation. Especially given that Mozi-Q presents a real risk. People apply it, believing the homeopathic hype and then go out and get bitten by a mosquito that potentially injects a non-homeopathic dose of West Nile virus.

Anyone wishing to still use citronella extracts will have purchase them in the U.S. where FDA or EPA see no problems. Don’t look for citronella in Europe though, their regulations are even stricter than Canada’s. But dog owners who have been using oil citronella to condition dogs from barking don’t have to worry, citronella scents will still be allowed for the device that hangs around their pet’s neck. And citronella extract will continue to be used extensively in the perfumery industry. Nobody smells a problem there.

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You Asked: Can ASEA improve health as advertised?

ASEAWhen I first came across a “wonder” product called ASEA on the web, I thought someone had come up with a clever parody.  The Internet of course is full of of ads for supplements, drinks and gimmicks of every conceivable variety that promise to keep us out of the clutches of the grim reaper.  There are extracts of exotic berries and herbs.  There are miraculous minerals and mushrooms.  There are oxygenated and magnetized waters.  And then there is ASEA.

The product’s name derives from the word “sea” and the Latin prefix “a” meaning “from.”  From the sea!  A very appropriate name.  The ingredients on the label tell the story.  Distilled water and salt!  What we have here is sea water!  That’s why I thought this was a parody.  Selling salt water as an anti-aging regimen?  Isn’t that sort of like selling ice to Arctic explorers?  I thought someone was making fun of all the nonsensical products being sold.  But it turns out that is not the case.  This is a real product, sold for very real money.  Lots of very real money.

Asea is promoted in ads as “Time machine in a bottle,” the message obviously being that imbibing in this salt water will turn back the clock.  Of course you can’t make any such claim on the product itself because that would require some sort of evidence, so the bottle simply says, “advancing life.”  A nebulous, meaningless statement.  I suppose one could say that since salt is essential to life, it does advance life.  But if you are going to make a case for selling salt water as a rejuvenation therapy, you have to come up with something a bit more impressive than “advancing life.”  So what claim did ASEA come up with?  “The world’s only Redox Signaling supplement.”

Someone must have been reading the scientific literature and came across “redox signaling,” an interesting and evolving area of research.  Our nerve cells communicate with each other through chemicals called neurotransmitters.  Some of these chemical messengers are free radicals, which are highly reactive species that can either gain or loose electrons, or in proper terminology, take part in oxidation or reduction reactions.  The term redox signaling is used when the chemical messengers between cells are free radicals.  What this has to do with ASEA is a mystery.  And we don’t get much help from the information on the label which states that “ASEA is a proprietary blend of naturally occurring reactive molecules derived from a patented redox balance process.  This unique process rearranges the constituent components into a beneficial mixture that is critical to to proper balanced cellular chemistry enabling the immune system to function at its optimum level.”  This is nothing more than meaningless double talk.  What reactive molecules are they talking about?  The only ingredient listed is salt.

I thought that perhaps I could learn something about the mysterious chemistry involved by watching the company’s video entitled “The Science Behind Asea.”  Turned out to be nothing more than a comic series of testimonials about improved mood and energy.  Of course you can get testimonials about anything either by hiring actors to play the role of satisfied customers or by interviewing people who are experiencing a placebo effect.  I’m still not convinced that this whole thing didn’t start out as a joke by someone wondering if they could sell something as ridiculous as salt water as a health product.  They found it worked, and now they are in the business that amounts to selling hair dye to bald people.  What I have to say to people promoting ASEA is “see ya.”

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Flowers, bells, birds didn’t lift the plague from all their houses

quarantineBecause of the Ebola crisis, the word “quarantine” is appearing with increased frequency in news reports and daily conversations.

The term derives from “quaranta giorni,” meaning 40 days, and traces back to the 14th century when the city of Dubrovnik, now in Croatia, was under Venetian rule. The Great Pestilence, or the Great Plague, as it was known at the time, was devastating Europe. As a form of protection, Dubrovnik declared that all ships and people had to be isolated for 40 days before entering the city. Later, the disease would be referred to as the Black Death — probably because of the gloom it brought, although some theorize that the “black” referred to the terrible dark bruising of the skin due to internal bleeding, a hallmark of the disease.

Between 1345 and 1360, the plague wiped out roughly half of Europe’s population. The cause was unknown, but it was clear that the disease was contagious. Once it took hold, it spread like wildfire. In Milan, doctors advised that victims should be walled up in their homes along with healthy family members — a measure that apparently worked, since Milan had the lowest death rate from the plague in all of Italy.

It would not be until 1894 that Alexandre Yersin of France’s Pasteur Institute would identify a bacterium as the causative agent while investigating an outbreak of the plague in Hong Kong. The bacterium, eventually named Yersinia pestis in his honour, is thought to have originated in Asia, where it found a hospitable environment in fleas, which would readily transmit it through their bites. Since fleas infested rats and mice, rodents that were regular passengers on ships, the disease spread throughout the Mediterranean and Europe.

Infection with the bacterium can take several forms, with “bubonic plague” being the most notorious. This term originates from the Greek for “groin,” due to the characteristic swellings of the lymph glands particularly in the groin, an area close to the legs, where flea bites are most likely to occur. In “septicemic” and “pneumonic plague,” bacteria enter the bloodstream and can be transmitted from person to person, especially though the coughing associated with pneumonic plague.

When science fails to find an explanation for a phenomenon, superstition and quackery rush in to fill the void. And there certainly was no scientific explanation for the plague in the 14th century. The Church decreed that the Black Death was punishment for human sin. Lepers, because of their outward signs that resembled the plague, were blamed, as were astrological alignments and volcanic eruptions.

“Flagellants” believed God’s punishment could be avoided by stripping to the waist and whipping themselves as they marched from town to town. Jews were also targeted, accused of poisoning wells. Many Jewish communities in Europe were exterminated in hopes of bringing an end to the plague. In Cologne, thousands of Jews were burned alive after being accused of starting the plague. Black cats also became victims. They were thought to be witches in an animal form, casting their spell on the population. Since cats were a natural enemy of the disease-carrying rats, hunting them actually increased the spread of the plague.

As far as treatments went, there were none. Since the plague was often accompanied by a terrible smell, people walked around with flowers under their noses hoping to ward off the stench and the disease. This, of course, did nothing. Neither did the burning of aromatic woods to purify the atmosphere. Other attempts to remedy the “bad air” included the ringing of bells and the firing of guns. Birds were released indoors so that the flapping of their wings would break up the pestilence. Bathing was thought to be dangerous, as was the consumption of olive oil. And one of the most bizarre pieces of advice given to men was that if they valued their lives, they must preserve their chastity. Apparently no such advice was given to women.

The belief that pleasant smells were of some help persisted through the 17th century, when the Great Plague once again terrified Londoners. The classic children’s rhyme about a “pocketful of posies” dates back to that time. Posies were flowers, but as the lyrics indicate, they did not do much good against the “ring of rosies,” the rose-coloured rash in the form of a ring around flea bites. The outcome of the disease was clear: “Atishoo, atishoo, we all fall down.” And some 100,000 citizens of London did.

Holding garlic in the mouth, swishing vinegar or burning sulphur to get rid of the “bad air” did no good. Smoking was also thought to be protective, and even children were forced to smoke tobacco, with threats of being whipped if they didn’t.

Cases of the plague still occur today, but they are rare. The first effective treatment appeared in 1932 with the advent of the sulphonamide drugs, but today the standard treatment is in the form of such antibiotics as streptomycin, chloramphenicol, tetracycline and the fluoroquinolones.

Unfortunately, the possibility of using the bacterium as a form of biological warfare exists. Indeed, recognition of the contagious nature of the plague resulted in the first example of biological warfare in 1347, when in an attack on the Crimean city of Caffa, the Mongols catapulted the bodies of plague victims over the city walls. More recently, in 1940, a Japanese plane dropped a load of infected rat fleas over a Chinese town, causing a local plague. Today, stories circulate about various countries having developed strains of the bacterium that are resistant to all drugs as bacterial warfare agents.

But for now, our major worry is the Ebola virus, and quarantine is the most effective way to halt its spread. In this case, about 21 days after exposure to an infected person is sufficient, that being the incubation period for the disease. If no symptoms appear after this period, there is no worry about the infection being passed on. It appears that contagion occurs only when symptoms are present. But if quarantine isn’t instituted when appropriate, we may have to confront a scourge that will outdo the Black Death.

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You Asked: Is fish really brain food?

brain foodIs fish really brain food? P.G. Wodehouse certainly thought so. In his wonderful “Jeeves” stories, Bertie Wooster encourages his brainy butler to eat more fish whenever a particularly challenging problem arises. But to what extent does fiction mirror real life? One can make a theoretical case for fish consumption based on the fact that docosahexaenoic acid, or DHA, the famous omega-3 fat in fish, is the main component of brain cell membranes, and that communication between brain cells is a function of the integrity of these membranes.

There is actually some experimental evidence to support a link between fish consumption and brain health. Infants born to mothers who consumed more fish during pregnancy have been shown to have improved verbal intelligence, better fine motor skills and pro-social behavior. A study has also correlated fish intake during pregnancy with IQ in 8-year old children. It is likely that these effects are due to increased blood levels of DHA in the offspring, but as is generally the case, the scenario is complicated. When blood is drawn from umbilical cords, it turns out that the concentration of the various fatty acids depends on the genetics both of the mother and the baby. In other words, depending on genotypes, an infant may benefit more or less from fish in the mom’s diet.

What about brain function at the other extreme of life, senior citizens? To get some insight here, researchers examined MRI brain scans of 260 individuals over the age of 65 who had normal cognitive function looking for differences associated with fish consumption as determined by dietary surveys. Subjects who ate baked or broiled but not fried fish every week had larger grey matter volumes in the areas of the brain responsible for memory and cognition. Interesting, but there was no determination as to whether these increased volumes translated to any change in brain power.

Curiously, no relationship was found with omega-3 fat intake as calculated from the diet surveys, suggesting that eating fish weekly may prevent brain ageing regardless of omega-3 content. But it may also be that eating fish is a marker for some other effect. People who ate fish were more likely to have a university education than those who didn’t. So perhaps it is mental exercise that was responsible for the changes in brain volume. There is also evidence that eating fish reduces the risk of heart disease. Maybe eating fish makes people smarter and more capable of understanding why they should be following the guidelines designed to reduce the risk of heart disease.

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Tempest in a K cup

K cupsA question came up about the risks of chemicals leaching out of those convenient coffee K cups. Yes, chemicals do leach out. That of course is the idea, you want to leach out the hundreds of compounds that contribute to coffee flavour and aroma and you also want a good shot of the stimulant caffeine. However, the likely reason for the question was concern about chemicals leaching out from the plastic. Yes, that happens too.

Anytime two surfaces come into contact, especially if one is a liquid, there will be transfer of chemicals. I don’t know exactly what plastic is used in these cups since the company maintains that this is proprietary information. By its texture, it seems the plastic is either polystyrene or polypropylene. It certainly is not polycarbonate which would be a source of bisphenol A (BPA). Traces of styrene, the compound from which polystyrene is made, may leach out. But styrene also occurs naturally in coffee beans, so all coffee will have some styrene. This is really not much of an issue because styrene is quickly metabolized and excreted.

If anyone has concerns about styrene, they had better stay away from cinnamon which can have as much as 39,000 ppb of styrene as opposed to the 5 ppb that may be leached out from polystyrene. They will also have to stay away from beer which has up to 25 ppb of naturally occurring styrene. If the K cup is made of polypropylene, there is no issue whatsoever. No compound of any consequence leaches out of this plastic. Basically what we have here is a tempest in a Kcup. If there is to be a concern, it centers in the environmental unfriendliness of these little cups which may pose a big problem in terms of where they end up.

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