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You Asked: How can homeopathic teething “remedies” that essentially contain nothing have an adverse effect on infants?

question markThe FDA in the U.S has raised alarm about homeopathic teething pills that may have caused seizures in babies and possibly even caused some deaths. But how can homeopathic “remedies” do this, given that they contain nothing? The bizarre tenet of homeopathy is that a substance that causes symptoms in a health person can relieve those symptoms in a sick person as long as it is diluted to an extent that contains almost zero or a just a trace amount of the original substance. Homeopathic teething remedies are made by diluting a solution of belladonna in an extreme fashion.

Why belladonna is the preferred substance is bizarre since according to homeopathic doctrine, to relieve pain, it should cause pain when used at a high concentration. While atropine, the active ingredient in belladonna can cause many adverse symptoms, it doesn’t cause pain. In any case, when diluted homeopathically, it should have no effect.

Now it seems some homeopathic companies are not very adept at making dilutions and the effects on the babies were likely caused by an overdose of belladonna. Dilution is really a very simple process, so it is hard to see how they could get it so wrong. It seems homeopaths are not only incompetent when it comes to understanding chemistry and medicine, some are also incompetent at carrying out dilutions. Obviously homeopathy is not always just benign nonsense.

Joe Schwarcz PhD

You Asked: Does the Magnetic Laundry System work?

question markMagnets are fascinating. Imagine the amazement of the ancient Greeks who discovered that some naturally occurring stones, later named magnetite because they were found in a region of Greece called Magnesia, attracted iron. The stones also quickly attracted superstitious beliefs. Magnetite was said to have had magical powers, the ability to heal the sick and frighten away evil spirits. Archimedes, in an undoubtedly apocryphal story, is said to have used magnetite to remove nails from enemy ships and sink them. Magnets never sank ships, but they were used to guide them. We are talking about the compass.

Thousands of years ago the Chinese also noted the properties of naturally occurring magnetite. When made into the shape of a needle and floated on water, the magnetite always lined up in a north south direction! By about 1000 AD, the Chinese had developed the compass that became the key to navigation. But magnets have also been used to navigate people away from reality. In the 1800s physician Anton Mesmer had people hold onto magnetized rods to attract disease out of their body. Mesmerism, as his antics came to be called, often worked. The success of the treatment had nothing to do with the magnets, rather it was based on the belief of the patient. Magnets are great placebos. Today, magnetized bracelets can be purchased to energize the gullible. And you can buy magnetic laundry disks for insertion into washing machines to allow laundry to be done without the use of detergents. The claim is that the magnets ionize water and thereby increase its cleaning ability. Nonsense.

Advertising for these products often attacks commercial detergents accusing them of containing cancer causing chemicals and hormone disruptors. The claim is that the magnetic disks reduce health risks by eliminating exposure to these substances while also saving money since there is no need to purchase detergents. Furthermore, use of the disks prevents the release of toxic substances into the environment. That all sounds very “green.” References are given to a patent for the laundry disks, as well as to a study supposedly demonstrating their cleaning efficacy.

It is important to understand that the only requirement for obtaining a patent is novelty. In this case, since nobody before had the idea of putting magnets into a washing machine, the patent was not hard to get. When it comes to the patent, there is no need to show that the magnets actually do anything, just that their use in this context is novel. How about the study carried out by a testing lab that examined the cleaning efficacy? Technicians actually took bundles of clothes, washed them in a magnet equipped washing machine and demonstrated they came out cleaner than they went in. Surprise, surprise! Water is an excellent solvent and cleans remarkably well even without any detergent. The “study” had no control. That is, there was no comparison between laundering with just water and laundering with the magnetized water.

Is there any rationale that the magnets can actually do something? Water is diamagnetic, which means that it will be repelled by a magnet. But the effect is very, very, small. If a vial of water is placed on a piece of floating Styrofoam and a strong magnet is brought close, it will slowly move away from the magnet. An interesting phenomenon, but nothing to do with cleaning ability. But there is something about the advertising for the laundry disks that is not contestable. They are guaranteed to last for fifty years, a guarantee that is indeed safe since magnets do not rot. That is more than what can be said about the claims of their miraculous cleaning properties.

Joe Schwarcz PhD

You Asked: Is it true that getting angry can affect the heart?

stressAccording to a study in the European Heart Journal, a single angry outburst can have immediate adverse effects. That’s because anger causes an increase in blood pressure and a release of the stress hormones adrenaline and cortisol. Indeed, the risk of a heart attack or angina is nearly five times higher in the two hours following an anger outburst than at other times, and the risk of stroke is four times higher. Let’s not get too carried away with this though, because at any given moment the risk of a heart attack or stroke is very low, so even a five fold increase in risk isn’t that great. To put the numbers into perspective, researchers estimate that if 10,000 healthy people have one anger outburst a month over a year, one of them will suffer a heart attack or a stroke as a result of the outburst. Among people who have other risk factors such as smoking, being overweight, high blood pressure or high cholesterol, there would be four cardiovascular events over a year with one monthly outburst. But among people who get angry more often, which is not an unusual scenario, the risk rises significantly. For example, if 10,000 people who also have other risk factors have five angry outbursts a day, some 600 of them will have a heart attack or stroke.

Joe Schwarcz

You Asked: Can coffee explode in the microwave oven?

coffeeA sensational sounding e-mail about “exploding coffee” has been making the rounds. It describes the misadventures of an unfortunate soul who heated up water for coffee in a microwave oven. When he picked up the mug, it “exploded!”

Explode is probably too strong a term, but spurting and frothing is a real possibility. This is due to a phenomenon known as superheating. First, we have to understand what boiling is all about. At the surface of a liquid molecules are always evaporating. If we leave a glass of water out, it will eventually disappear.  If we heat the liquid, its molecules move faster, become more energetic and more molecules go into the vapour phase. As a consequence, the liquid disappears more quickly. At the boiling point, molecules all over the liquid, not only at the surface are energetic enough to go into the vapour phase. They do this most readily by evaporating into airspaces that exist in the container. All containers have imperfections where air gets entrapped when a liquid is introduced. As these air pockets fill with vapour, they expand and begin to rise. That is why we see streams of bubbles which originate at the sides or the bottom of the container.

In a microwave oven, the container is not heated, only the water.  So the container actually cools the liquid in contact with it, meaning that the liquid in the center is always hotter, sometimes by as much as 10 degrees C. But the liquid in the center cannot boil, because there are no air bubbles for it to evaporate into.  By the time the liquid near the edge of the container reaches the boiling point, the liquid in the middle is considerably hotter; it is superheated.

The addition of sugar or a tea bag now can spur vigorous boiling. This is because the surface imperfections introduce trapped air bubbles into which the superheated liquid vaporizes. Sometimes just picking up the container can have an explosive effect as the superheated liquid comes into contact with air bubbles on the periphery. Accidents can be prevented by putting a plastic spoon into the mug or glass while it is heating in the microwave. In this case the scare-mongering note about “exploding coffee” may actually has some basis in fact.

Joe Schwarcz PhD

You Asked: What is natamycin?

natamycin“The customer is always right,” is a time-honoured adage in marketing. It holds true even if the customer is wrong. If the customer does not want “artificial” preservatives” in food, industry will comply, whether that move is supported by science or not. Of course no company wants to poison its customers, so eliminating preservatives is a risky business. What’s the answer? Look for a “natural” preservative. That will satisfy the consumer who has a disdain for anything artificial, and at the same time will reduce the worry for the producer about marketing an unsafe product.

Kraft, for example, has announced that, at least in the U.S., it will be replacing artificial preservatives with natural ones in its cheese products. This boils down to not much more than a question of semantics. Sorbic acid and its salts, the “artificial” preservatives that have been used, are to be replaced by natamycin, an antifungal compound produced by soil bacteria. Although many cheeses are actually mould ripened, with blue cheese being the classic example, cheese is also prone to infection by a variety of rogue moulds that can cause spoilage. Sorbic acid and its salts can prevent the growth of moulds, yeast and fungi, even when used at concentrations of less than 0.1%. It was back in 1859 that Professor August Wilhelm Hofmann first isolated sorbic acid by distilling the oil obtained from the berries of the rowan tree. This is the same Professor Hofmann who was enticed to England by Prince Albert to head up the newly created Royal College of Chemistry and who essentially founded the synthetic dye industry.

So, doesn’t the fact that sorbic acid can be isolated from berries make it a “natural” substance? Yes. And I suppose there would be no clamoring to remove it from food if this is how it were produced. But distilling sorbic acid from rowan berries is not an economical process and would not do for the estimated 30,000 tons needed every year by the food industry. But sorbic acid can also be readily produced by a number of synthetic methods, including the reaction of crotonaldehyde with ketene, both of which can be made from compounds isolated from petroleum. This synthesis is economically viable and is the way that sorbic acid is produced. Any chemical is defined by its molecular structure which does not depend on the route by which it was produced. The sorbic acid produced by the rowan berry is identical to the sorbic acid produced by chemical synthesis, but because the latter was not extracted from a natural source, it is termed “artificial,” and therefore in the eyes of some people, suspect. The fact is that sorbic acid, irrelevant of the source, is a food additive that has passed all the regulatory hurdles just like its replacement, natamycin.

Natamycin is an antifungal agent produced by a soil bacterium that was first found in South Africa’s Natal province, hence the name. Since bacteria occur in nature, any of the chemicals they crank out can be classified as “natural.” But curiously a substance that occurs in nature, like sorbic acid, is termed an artificial preservative when it is synthesized in the lab. Natamycin may be natural, but it would not be so appealing to people if they knew they were eating the waste product of dirt bacteria. Not that there is anything wrong with that.

Joe Schwarcz PhD

You Asked: Why does a cooked onion taste sweet and how come cutting a cooked onion does not make the eyes water?

onionOnion chemistry is extremely fascinating and extremely complex! We’ve been intrigued by this vegetable ever since our prehistoric ancestors gathered and cooked wild onions. By the time of the First Egyptian Dynasty 5000 years ago, onions were widely consumed for flavor and for their supposed medicinal properties. At various times they have been associated with the prevention of colds, loosening of phlegm, correction of indigestion, inducement of sleep, stimulation of appetite, disinfection of wounds and the elimination of parasites from the digestive tract. In ancient times people believed that onions were a symbol of eternity because of the concentric circles that make up their structure. For this reason, onion shaped towers became popular in Russia and Eastern Europe; the idea was that these buildings would stand forever.

Onions may not make us live forever but some of their components may indeed have medical benefits in reducing cholesterol, blood pressure and perhaps even the risk of cancer. This is why their chemistry has received a great deal of attention. The smell produced by a cut onion is actually a form of chemical warfare the plant has evolved to ward off pests. When an insect attacks the bulb, tissue damage unleashes a sequence of chemical reactions resulting in the release of propanethial oxide, an irritating substance designed to repel the attacker. This reacts with moisture in the eyes to form sulphuric acid which is the stuff that makes our eyes water. Unfortunately, to the onion, attack by an insect or a sharp knife appears to be the same.

Frying the onion causes yet another reaction, resulting in the formation of bispropenyl disulfide which has a sweet smell and a sweet taste. Some of the harsher tasting compounds are also destroyed by the heat, explaining the change in flavor. Furthermore, we do not cry over cooked onions because heat destroys the enzymes that are needed for the formation of propanethial oxide. Also the cooking process drives off any volatile irritants.


Joe Schwarcz PhD

You Asked: Is it true that they add cyanide to salt?

saltYes, sort of. Some commercial varieties of salt have small amounts of sodium ferrocyanide added to prevent caking. When humidity is high, a thin layer of moisture forms on the surface of the salt crystals, and some of the salt dissolves in this layer to form brine. If the relative humidity then drops, the water evaporates and the brine solution recrystallizes between the salt crystals, causing them to aggregate into clumps. Ferrocyanide decreases the solubility of salt in water so the salt is less likely to dissolve in the moisture that coats the crystals and that in turn reduces the amount of recrystallization.

Any mention of cyanide conjures up images of poison so the presence of ferrocyanide in salt sounds scary. That’s why producers would rather list it on a label as “yellow prussiate of soda,” an old-fashioned term first coined in reference to Prussia, the country where it was originally synthesized. There is, however, no need to be terrified of ferrocyanide because the cyanide in this compound is tightly bound to an iron atom and is not released in the body. Even if it were, it would be irrelevant because the amount would be way too little to cause any harm. And ferrocyanide itself is remarkably non-toxic.


Joe Schwarcz

You Asked: Why does a barber’s pole has a red stripe?

barber poleIt represents the colour of blood. During the Middle Ages monks were required to shave the crown of their head, a function commonly performed by itinerant barbers. Also, under ecclesiastic law, monks had to be periodically bled. This was supposedly a symbol of piousness, of devotion to God.
Barbers began to attend to this duty as well. They would travel with a “flag” of a white cloth dipped in blood to indicate that they would attend to anyone who needed to be bled. This early mode of advertisement eventually was transformed into the barber’s pole. And the pole began to symbolize more than haircuts and bleeding. Barbers began to expand their role and became quasi surgeons, specializing in sewing up wounds and extracting teeth. They also dabbled in the whitening of teeth by dabbing them with nitric acid. This did produce an immediate whitening, but destroyed the teeth in the long run by wearing away the protective enamel.
But at least one 16th-century barber surgeon, Ambroise Pare, made an important contribution to medicine. Barbers in those days worked under the guidance of physicians, who thought themselves above menial jobs like cutting and scalding. Why scalding? Because physicians thought that gunpowder was poisonous and therefore gunshot wounds had to be treated with boiling oil to destroy the poison. Unfortunately, if the bullet didn’t kill the victim, the scalding often did.
During the siege of Turin in 1537 Pare ran out of oil and for some reason substituted a cold mixture of egg yolks, oil of roses, and turpentine. To his surprise, the soldiers treated with this mixture fared better than those who had been scalded. And thus ended the brutal practice of pouring hot oil into bullet wounds. The French-trained Pare was a religious sort, and thought he had had help in making his observation. That’s why he introduced the oft-repeated phrase, “I dressed the wound, but God healed him.”

Joe Schwarcz

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