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The Secret World Inside Us

gut microbiomeRecently, there’s been an influx of media attention on guts. More specifically, the microbes that live in your gut. Extensive research is being done on these little guys as they seem to be having a real impact on our health. These gut microbes may be miniscule but their function is major. And I learnt all about them at “The Secret World Inside You” exhibit now on display at the American Museum of Natural History in New York.

Before I begin walking you through the exhibit, first a brief explanation as to what microbes even are. Microbes are microscopic living organisms that can only be seen with the help of a microscope. And they are everywhere – in every fold and lining of our bodies, including our inside. They literally govern the world inside us and are responsible for much of how we function.

Our skin is the first point of contact for microbes, which is most probably why it’s the first section you get to in this exhibit. There is not one individual whose microbiome is like that of another. However, what came as a real shocker was the fact that people living together – families, roommates, and yup, pets too –share certain microbe make-up. So much so, that when one person leaves the nest for a few days, the microbiome of the house shifts until they return home again. Pretty sweet, no? Everyone sharing the same types of microbes…(It could also be slightly gross if you think about it too much, so just don’t). It was also pointed out how certain microbes, as distant as they may seem, are actually closely linked. Let’s take cheese, for example. The holes in Swiss cheese are made from a bacterium that is similar to one located on the skin, which is why (some) feet take on a cheesy-like smell. On feet, the Brevibacterium linens bacteria converts amino acids into smelly sweat, but in the world of dairy, it serves to ripen Limburger cheese. Delicious? Depends.

Now perhaps it’s my age and the fact that my ovaries now twitch on a regular basis thanks to all the babies on my FB feed, but the next section of the exhibit was hands down my favourite. “Before Birth”, the world of the baby and the microbiome of the mama. Now one would think that the two are inextricably linked since the fetus is totally reliant upon the mother; however, to my surprise, the mother’s microbiome does not mix with the fetus at all. In fact, if the microbiome of the mother interacts at all with the fetus, it could be very risky. And it’s thanks to the placenta, the gatekeeper in this whole process, why the two don’t mix. After visiting this exhibit, I really developed a whole newfound respect for the placenta since it serves a pivotal function, allowing nutrients and oxygen to enter the amniotic sac and preventing any other materials from doing so.

Now once a woman’s water breaks all rules are off. The baby is now cooked enough to not only mingle with the microbes of its’ mother but to start developing a microbiome of their own. And the birth canal is where this all happens. When the baby travels through the canal, the mother’s microbes get pressed into the skin, nose and eyes, and even swallowed by the little one before being delivered to the baby’s gut where they can then start their own gut microbiome. This process is crucial in the development of a baby’s healthy immune and digestive system. (How awesome!) But you may be wondering (as was I), about those C-section deliveries since these babies do not go through the birth canal picking up the mother’s microbes along the way. Instead, these babies pick up microbes from the doctor’s hands and the environment. They end up lining the baby’s digestive tract and in turn have an impact on their immune system, causing C-section babies to be at a higher risk of a variety of conditions, such as asthma and allergies. To test this, studies are now being done where the baby, immediately post-C-section delivery is slathered with a gauze pad that soaked up the microbes in their mother’s birth canal right before birth. Time will tell whether this can benefit the baby but most signs point to yes, which is good news since about one mother in three now gives birth by C-section in the United States.

As life goes on, microbes live, grow and multiply based on what we feed them. Meaning, the food we eat and the choices we make influence our gut bacteria. This has spawned a huge new area of research looking at individual variation when it comes to weight gain and loss, which was another section of the exhibit that I found fascinating, since like the majority of people on the planet I have a few pounds that just won’t relent.

Different people react to different foods in different ways. This is not a novel idea. I mean, just look at allergies and adverse food reactions. Some people have them, some people don’t. But what if this can be attributed to the type of microbes living in your gut? Let’s take a “healthy” food like a tomato, for example. Could you imagine if someone’s blood sugar spiked after eating tomatoes the same way it would after eating a donut? And research has shown, that this is the case! And yet in another individual, tomatoes can have zero spike effect. This whole new line of research could be a breakthrough in terms of weight control. Costly, but important. I know I’d be among the first to sign up to find out just what type of bacteria I have going on in my gut. Of course, as the exhibit suggests, one cannot know whether obese people are obese due to their microbiome or if there are external factors that caused their microbiome to be as such in the first place. It’s the chicken or the egg debate and we shall leave it to science to continue the research.

After leaving the exhibit, I realized that the microbiome is truly a hotbed of scientific research. We know so much but at the same time there are so many question marks about how we can use, manipulate, and alter our microbiome to enhance our health. And I am confident that science will, at one point or another, provide us with these answers; but until then, I’m just going to hope that my gut bacteria interact favourably with tomatoes.

You can visit “The Secret World Inside You” exhibit at the American Natural History Museum in New York where it will be on display until August 2016.

Emily Shore

Getting ‘Steinached’ was all the rage in Roaring ’20s

Serge VoronoffThe Great War was over, cars were multiplying on the streets, radios were crackling in living rooms, plastics were hitting the market and theatres were attracting people with newfangled moving pictures. Science and technology were roaring ahead. It was, after all, the “Roaring Twenties.” But in Vienna, there was another kind of roar. It was emanating from thousands of older men who claimed to have regained their virility through what seemed to be a stunning advance in medicine. They had been “Steinached!” The men had undergone a 20-minute procedure introduced by Dr. Eugen Steinach in which one of their seminal ducts was tied off. In other words, the men underwent a partial vasectomy. The goal wasn’t prevention of pregnancies, it was rejuvenation.

Steinach’s work was stimulated by French physiologist Charles-Édouard Brown-Séquard’s seminal lecture delivered to members of La Société de biologie in 1899 in which he described having injected himself with filtered extracts from the crushed testicles of young dogs and guinea pigs to regain the vigour and intellectual stamina of his youth. The professor had also tested himself with a dynamometer, a device that measures mechanical force, and found that his muscle strength had also been renewed. He capped off the lecture by telling his rapt audience that just hours earlier he had passed the final test of his experiment by “paying a visit” to his young wife.

The scientific community, however, did not buy Brown-Séquard’s claim that the key to rejuvenation was injection of minced gonads. The prestigious Boston Medical and Surgical Journal opined that “the sooner the general public and especially septuagenarian readers of the latest sensation understand that for the physically used up and worn out there is no secret of rejuvenation, no elixir of youth, the better.”

Biology professor Eugen Steinach, however, thought Brown-Séquard’s work with gonads was worth pursuing and turned to transplanting the testes of a male guinea pig into a female. She then exhibited mounting behaviour characteristic of a male. Steinach concluded that the gland’s secretions were responsible for sexuality and even theorized that homosexuality in men could be treated by transplanting a testicle from a “normal” man into a recipient in need of “remasculinization.” Thankfully that idea didn’t fly, but surgeon Serge Voronoff’s notion of grafting monkey gland tissue onto the testicles of aging men did.

While serving as physician to the king of Egypt, Voronoff had noted that the court eunuchs were often sickly and seemed to age very quickly. The testes, he concluded, played an important role in maintaining vigour, and that “possession of active genital glands was the best possible assurance for a long life.” In 1918, he believed he made his point when he restored an aging ram’s youthful vitality by transplanting the testes of a young lamb.

Voronoff upped the ante by transplanting the testes of executed criminals into aging men rich enough to pay for the procedure. But demand soon outstripped supply, and since few young men were willing to part with their precious parts even for rich compensation, Voronoff came up with an alternative scheme. He would transplant bits of chimpanzee and monkey testes onto the genitals of elderly men. Eventually more than a thousand men underwent the monkey gland treatment at the hands of doctors around the world, with the requisite material often being supplied by a monkey farm Voronoff set up on the Italian Riviera.

Steinach bought into Voronoff’s idea, but thought that the benefits ascribed to transplants could be achieved by an alternate procedure. Damming the seminal canal would stimulate the testes to produce more male hormones! At the time, researchers had determined that there were two types of tissues in testicles. Seminal tubules produced spermatozoa, but there were also “Leydig” cells between the tubules that released sex hormones. Steinach’s idea was that the two types of tissues compete for nourishment, and that stifling the sperm-producing tissues would boost the production of the sex hormones.

In his book, Sex and Life, Steinach described how his patients “changed from feeble, parched, dribbling drones, to men of vigorous bloom who threw away their glasses, shaved twice a day, dragged loads up to 220 pounds, and even indulged in such youthful follies as buying land in Florida.” He believed in his procedure so strongly that he “thrice reactivated himself.” It isn’t clear what he meant by “thrice,” because once the duct is tied off, it’s tied off. Whatever improvement Steinach and his patients felt was probably due to wishful thinking, because as we now know, vasectomies do not boost hormonal output by the testes.

Steinach had testimonials galore, including from some very famous people such as Sigmund Freud, who underwent the procedure when he was 67 years old, hoping to improve his “sexuality, his general condition and his capacity for work.” William Butler Yeats, the famed writer, was Steinached when he was 69. “It revived my creative power,” Yeats wrote in 1937. Apparently in more than one way. The doctor who performed the snip invited a woman half Yeats’s age to dinner with the aim of allowing the writer to make a connection and test out his newly embellished virility. It seems the outcome was successful, with Yeats publicly reporting on his “second puberty,” leading to the Dublin press nicknaming him the “gland old man.”

While it is now clear that Brown-Séquard, Voronoff and Steinach promoted procedures that did not have the claimed efficacy, they did lay the foundations for further research that resulted in the isolation of testosterone, the male sex hormone. In 1927, University of Chicago chemistry professor Fred Koch isolated 20 milligrams of a substance from 20 kilos of bull testes that remasculinized castrated roosters, pigs and rats. By 1935, Schering’s Adolf Butenandt had worked out the molecular structure of testosterone, the active compound in the bull testes, which allowed him to come up with a chemical synthesis from cholesterol. Today, testosterone and various derivatives are prescribed to men with low blood levels who often claim to experience the effects that were thirsted for by men who subjected their privates to the scalpels wielded by Drs. Steinach and Voronoff in the Roaring Twenties.

 

 Joe Schwarcz

Joe Schwarcz: James Simpson, chloroform pioneer, took the pain away

SimpsonThe experiment, James Simpson decided, would go ahead even though the rabbits had died. And that decision was destined to have such a huge impact on medicine that more than 100,000 grateful Scots lined the streets of Edinburgh in 1870 to pay their respects as Simpson’s funeral cortège passed by. Many had undergone surgery or had given birth to children painlessly thanks to Simpson’s great discovery: chloroform.

Not many students graduate with a medical degree at age 20, but James Simpson did. In the early years of the 19th century, doctors didn’t have many tools at their disposal, and young Simpson was particularly disturbed by the suffering he witnessed in the surgical theatre. He once remarked that “the man laid on an operating table in one of our surgical hospitals is exposed to more chances of death than the English soldier on the field of Waterloo.” No surprise, then, that when word came from America of the discovery of ether as an anesthetic, Simpson was quick to jump on the bandwagon.

But there were problems with ether. It was flammable and difficult to administer, and often made patients sick. But Simpson reasoned that if ether could put people to sleep, there had to be other chemicals that could do the job as well. And who better to ask for suggestions than Scottish chemist Lyle Playfair, who had trained under the famed German professor Justus von Liebig?

Playfair was no expert in putting people to sleep, but he told Simpson about a sweet-smelling volatile liquid he had seen Liebig prepare back in 1832. It just so happened, Playfair went on, that one of his assistants had recently made some, and Simpson was welcome to give it a try — with one proviso: the experiment would first have to be tried on two rabbits. It seems Playfair didn’t want to be responsible for any harm that could befall the eager Simpson, who was already establishing a name as a caring, skilled physician.

The rabbits were exposed to the vapours of chloroform and promptly fell asleep. When they awakened with no apparent side effects, an exuberant Simpson grabbed a bottle of chloroform and made plans with his physician friends George Keith and Matthew Duncan for a little chloroform party the next day. The three had already been into sniffing a variety of chemicals in hopes of finding an improved anesthetic, but Keith and Duncan suggested it would be a good idea to check on the rabbits in the morning for any lingering effects. Well, there were lingering effects all right. The rabbits were dead!

Why this did not deter the trio from experimenting with chloroform isn’t clear. Perhaps it was their drive to become medical pioneers, or maybe they had enjoyed the effects produced by some of the chemicals they had previously inhaled. In any case, on the evening of Nov. 4, 1847, Keith became the first guinea pig, inhaling a good dose of chloroform. Within a couple of minutes he was under the table. Without waiting to see their colleague’s fate, Duncan and Simpson followed suit. After some initial hilarity, they also passed out. On awakening, Simpson declared that “this is far stronger and better than ether,” and predicted chloroform would “turn the world upside down.”

The young doctor was so impressed that he immediately hired a chemist to prepare a fresh supply of chloroform, which in those days was made by reacting acetone with chlorine. Four days after his sniffing binge, Simpson chloroformed a woman, who 25 minutes later gave birth. Within a month, Simpson had used chloroform successfully on more than 50 patients.

Still, as with any drug, there were risks, including death. In 1848, young Hannah Green died, probably due to improper administration of the anesthetic for the removal of an infected toenail. Soon after this tragedy Dr. John Snow developed an inhaler that regulated the dosage of chloroform and reduced the risk of such deaths. Simpson was then able to quiet those who still deemed chloroform to be too dangerous by keeping careful statistics on successes and side effects. When detractors claimed that chloroform was unnatural, Simpson replied that “so are railway trains, carriages and steamboats.”

Religious opposition, however, was harder to overcome. The faithful argued that pain relief during childbirth was unholy because according to the scriptures women were destined to be punished for Eve’s original sin. Tempting Adam with the fruit of the tree of knowledge, it seems, was not a good idea. Critics pointed to a passage in Genesis where God tells Eve that “I will increase your pains in child-bearing; with pain you will give birth to children.” Simpson cleverly retorted that anesthesia was actually inspired by God, who can be regarded as the world’s first anesthetist. He had his own biblical reference: “So the Lord God caused the man to fall into a deep sleep; and while he was sleeping, he took one of man’s ribs and closed up the place with flesh.”

Still the battle between the pro- and anti-chloroform forces raged for several years, finally abating in 1853 when Simpson recommended chloroform to his most famous patient, Queen Victoria. After giving birth to Prince Leopold, the Queen expressed herself “much gratified with the effect of the chloroform.” If chloroform was good enough for Her Majesty, it was good enough for her subjects!

As the 20th century rolled in, chloroform began to show a notorious side as well. Criminals had taken to incapacitating victims by clamping a rag soaked with the liquid over their mouth. Then, in a highly publicized case in 1901, American businessman William Marsh Rice, whose fortune founded Rice University, was killed by his valet, who aimed to get his hands on Rice’s assets. The murder weapon was chloroform.

More problems cropped up by the 1930s, with chloroform being linked to liver problems and irregular heartbeats that sometimes proved fatal. Finally, as new sleep-inducing agents like isoflurane and desflurane were introduced, the use of chloroform as an anesthetic was relegated to the junk heap of history. But in its time, that “junk” was responsible for alleviating a great deal of suffering. In commemoration, an impressive bronze sculpture of Simpson now dominates Princes Street Gardens in Edinburgh, with the inscription, “Pioneer of Anaesthesia.” Indeed he was.

Joe Schwarcz

Arsenic in Treated Wood

plastic benchWhat comes to mind when you think of arsenic?  Inheritance powder?  The possible murder of Napoleon?  Poisoned wells in Bangladesh?  Well, how about playgrounds, decks or picnic tables? 

Concern has been raised that children cavorting around playground equipment made of treated wood may be exposed to dangerous amounts of arsenic.  Decks and picnic tables have also been accused of compromising our health by attacking us with arsenic.  The culprit at the center of the accusations is “chromated copper arsenate,” commonly abbreviated as CCA. Until 2004, this chemical was commonly blasted into wood under pressure to increase its longevity.

Wood is susceptible to attack by fungi and insects and usually rots in a couple of years if untreated but treated wood can last up to ten times as long.  Copper is an effective fungicide, arsenic is lethal to insects and chromium fixes the concoction in place to minimize leaching.  Still, when the preserved wood contacts soil, water, or even skin, some of the arsenic does escape.  Nobody contests the fact that arsenic is extremely toxic or that it may trigger cancer.  The question, as always with exposure to toxins, is dosage.
Without a doubt there are instances in which treated wood has caused poisonings.  Or more appropriately stated, there are cases in which people have poisoned themselves by working with treated wood carelessly.  A U.S. Forest Service worker became extremely ill after sawing treated wood to build picnic tables.  This really was no great surprise since arsenic can attack the nervous system, kidneys, lungs, stomach and liver.  He wore no mask, so he inhaled and ingested the fine sawdust leading to dramatically high levels of arsenic in his blood.  But this situation is not comparable to children playing in a park around pressure treated wood structures.  The playground scenario has, however, been studied.  To mimic a “worst possible case,” a weighted wooden block covered with a moist cloth was repeatedly dragged back and forth over treated wood to estimate the amount of arsenic a hand would pick up.  Then making a reasonable guess about hand to mouth contact, because arsenic does not go through the skin, the researchers calculated a maximum ingestion of 5 micrograms.  What does this mean?  Well we consume about 4-12 micrograms of arsenic naturally every day in our food supply and such amounts have not been linked with problems.  Indeed associations with cancer, and even these are tenuous, only become apparent when drinking water has an arsenic concentration of several hundred micrograms per liter, as is unfortunately the case in some areas in Asia.
So I really don’t think that our children are being poisoned by arsenic in playgrounds.  It goes without saying that treated wood should not be burned and that proper precautions should be taken when working with the substance.  In any case though, chromated copper arsenate has been replaced for non-industrial purposes by two safer materials, Ammoniacal Copper Quaternary (ACQ) and Copper Boron Azole.  But if you are still worried about your decks or picnic tables, you can always use cedar wood which naturally resists insects and fungi.  Or if you really want to be avant-garde, you can use synthetic lumber made from recycled plastic soft drink bottles.  You see, there is some value to soft drinks.
Joe Schwarcz

PCBs are Not “Toxic Time Bombs”

PCBWe haven’t heard much about polychlorinated biphenyls, or “PCBs” since the fire at St. Basil-Le Grand in 1988, but we sure are hearing a lot now. There are two angles to the illegally stored PCB-filled transformers and contaminated waste in the Pointe Claire facility. There is the legal and political story, and then there is the scientific one. Without question, the PCB-containing materials were improperly and illegally stored and will have to be removed and properly processed. That is the law. And that part of the story was accurately portrayed by the media. But when it comes to the science, the risk posed by the stored chemicals as well as the “toxicity” of PCBs, in my view was exaggerated, generating an unwarranted degree of public anxiety. One got the impression that a cache of nerve gas had been discovered as headlines screamed about “toxic time bombs,” apparently ready to explode. In fact, PCBs are not the devil incarnate.

PCBs are non-corrosive, non-conducting, fire-resistant chemicals that were widely used in transformers, fluorescent light ballasts and hydraulic machinery until the late 1960s when an incident in Japan drew attention to their potential toxicity. About 1500 people became ill after consuming rice oil that had become contaminated with PCBs then used as a heat transfer medium in a process to deodorize the oil. The PCBs leaked into the rice oil through small holes in the pipe. Since the PCB-based heat transfer liquid was heated to 200oC in this process, there was a conversion of some of the PCBs to polychlorinated dibenzofurans (PCDFs) which are far more toxic than PCBs and were the likely cause of the gastric symptoms, jaundice, eye discharge and persistent skin eruptions (chloracne). Some long-term consequences were also noted. Women who had consumed the contaminated oil during pregnancy gave birth to slightly smaller babies who also experienced developmental problems. But numbers and measurements are critical to science. The Japanese victims consumed somewhere between half a gram to two grams of PCBs, which is several million times more than the amount anyone in North America could be exposed to even if they consumed fish from the most PCB contaminated waters.

The Japanese accident and a similar one in Taiwan in 1979 unleashed a flurry of research about the toxicological impact of PCBs. Electrical industry employees were extensively surveyed and few problems surfaced even among those who had spent thirty years working elbow-deep in PCBs. There was an observation of slightly higher death rates from rectal and liver cancers, but this was contentious because lifestyle characteristics such as alcohol consumption and diet had not been appropriately controlled for. Animal experiments on the other hand clearly showed that PCBs were toxic and even capable of triggering cancer. But again, let’s look at the numbers.

If we assume that humans react similarly to rats, a daily dose of some 8 mg per kg of body weight would be required to possibly cause a problem. This is about 500,000 greater than what the average person is exposed to on a daily basis. Still, the hint from from human occupational exposure and the animal data were enough to classify PCBs as “probable human carcinogens.” That classification is often misinterpreted. It just means that a substance is capable of causing cancer at some dose under some sort of exposure. It is interesting to note that Inuit populations in Quebec have some of the Highest PCB exposures with many women having higher than average levels of PCBs in breast milk yet the incidence of cancer is below the Canadian average.

One further concern is that PCBs have possible hormone-disrupting properties, which may indeed be the case. But there are numerous substances that we are exposed to, both natural and synthetic, that have such effects. In any case for any significant consequences, long term exposure would be required in the form of contaminated food. Basically then, PCB’s are not particularly toxic. Benzene, to which we are regularly exposed from gasoline, benzopyrene from wood-burning stoves and heterocyclic aromatics in barbecued foods are more “toxic.”

Now, back to Point Claire. PCBs have very low volatility and the trace amounts that evaporate dissipate quickly in air. We know this from the extensive studies that have been carried out in the vicinity of the Hudson River into which General Electric once reprehensibly dumped large amounts of PCBs. The river represents a huge source of possible airborne PCBs yet studies have shown no significantly elevated air levels in the vicinity and people living in the area do not have higher than normal background blood levels. The Pointe Claire site would be a far, far smaller source of PCB release.

In any case, as far as inhaling PCBs from leaks, it is a non issue. According to the U.S Environmental Protection Agency, the intake of PCBs that will not cause any harm is 20 nanograms per kg body weight per day. This is referred to as the “reference dose.” Since babies would be at greatest risk,  let’s use them as an example. An infant would have to be exposed to air at a concentration of 70 nanograms per cubic meter to approach the reference dose. Measurements, even in areas near contamination sites, show levels 100 fold below this! PCBs are simply not volatile enough to represent a risk through inhalation. As far as possible contamination of the ground goes, no great issue here either. PCBs are very insoluble and bind to sediment. Trace amounts may be detected in the water table under the site but this is not the water that runs out of taps.

If PCBs have such low toxicity, why were they banned in the first place? Two reasons. They are extremely stable compounds and do not break down in the environment which means that further production would increase the amount dispersed around the globe and create a difficult situation should significant adverse effects come to light in the future. Second, PCBs are fat soluble, meaning they are not readily eliminated through the urine and build up in the food chain. Continued release into the environment would lead to increased body loads with possible health consequences. Given that alternate chemicals were available, the ban on PCBs was reasonable, although there is no guarantee that the replacement chemicals will prove to be less problematic.

In any case, neither storing PCBs illegally nor withholding of information by governments can be condoned, particularly because a fire at such a facility could result in truly dangerous furans and dioxins being released. However the chance that anyone would suffer any adverse effect that could be linked to the stored PCBs I believe borders on zero. But the effects of the stress caused by the unrealistic portrayal of a “toxic time bomb” may not be zero.

Joe Schwarcz

Professor Aldini’s Strange Antics

aldiniProfessor Aldini began by swabbing the ears with salt water.  Then he attached a metal wire to each ear and proceeded to connect them to a battery.  Almost immediately the subject’s face contorted into a grimace and his eye-lids fluttered uncontrollably.  The onlookers were absolutely horrified.  Not because the facial expression was particularly scary, but because there was no body attached to the head!
The headliner for this ghoulish event that took place at the end of the eighteenth century was a professor of physics at the University of Bologna in Italy.  Giovanni Aldini, being a nephew of Luigi Galvani, had a natural interest in “galvanism,” the application of an electric current to body tissues.  It was back in the 1780s that Galvani carried out the experiment that would forever enshrine his name in physics texts.  By poking a dead frog simultaneously with rods made of different metals, he had managed to make its muscles twitch!  Galvani misinterpreted his finding, believing that his manipulations had released some form of “animal electricity.”  It was Galvani’s countryman Alessandro Volta, who correctly concluded that the dissimilar metals, and not the frog, were responsible for the generation of an electric current.  The frog was just providing a medium through which current could flow, and it was this flow of electricity that caused its muscles to contract. 
Aldini was fascinated by the effects his uncle had discovered and managed to convince the authorities in Bologna to donate the bodies of executed criminals for further study of galvanism.  While he was a dedicated scientist, Aldini was also a showman, carrying out his experiments in a theatrical atmosphere open to spectators.  He stimulated the severed heads of cows, horses, dogs, and people with an electric current and demonstrated that the teeth could be made to chatter and the eyes roll.  But Aldini’s most dramatic experiments involved intact bodies. 
Perhaps his most famous “performance” took place in 1803 at the Royal College of Surgeons in London.  George Foster had been sentenced to hang for murder, and the judge had decreed, in a fashion not unusual for the times, that his body be used for anatomical dissection.  In front of a large crowd of doctors and other spectators, Aldini went to work.  As always, he generated an electric current with a “voltaic pile,” the forerunner of the modern battery.  Developed by Volta, based on Galvani’s observation, the pile consisted of a set of alternating zinc and silver plates separated by pieces of paper soaked in salt or sulphuric acid.  In such an arrangement electrons flow from the zinc to the silver, generating a current. 
Aldini connected a pair of metal rods to the top and bottom of the pile and proceeded to use them to prod Foster’s body.  When he attached one probe to the ear and the other to the mouth, the jaw quivered and an eye opened.  But the most spectacular result was produced when Aldini maneuvered one of the probes to the rectum.  Foster’s body went into convulsions and his arms flew up!  It seemed to the spectators that the dead man was on the verge of standing up!  Of course he did nothing of the sort, but the audience did leave with some novel insight into the dramatic effects that an electric current could produce on muscular systems. 
Aldini was not the only one to carry out such grisly demonstrations.  In Germany, Karl August Weinhold horrifyingly scooped out a cat’s cerebellum, removed its spinal cord, and filled the cavities with silver and zinc.  He reported that “the two metals caused the previously deceased animal to regain its pulse and to become animated once again.”  Obviously, not for long.
Joe Schwarcz

A Formula for Science

formula one carI’m not a huge fan of automobile racing, but I do admit to catching a bit of the fever when the Formula One cars roll into town. There is something captivating about these machines, capable of attaining speeds well over 300 km/hr, as they push technology, engineering and driving skills to the limit. This is not a cheap sport. The budget for a Formula One team can run upwards of $120 million a year! Just the tires cost a couple of thousand for a set, and they only last for half a race. Of course these are not ordinary tires. They are made from a variety of specialized rubber compounds that can provide tremendous gripping power, the choice of specific tire being determined by weather conditions. The tires grip better as temperature increases and sometimes pre-heating is required.

There seems to be some confusion about what “Formula One” means. It does not refer to the fuel that is used. But the composition of the fuel is part of the “formula,” which actually refers to the set of regulations that define every aspect of the car as well as how the race is to be run. Perhaps surprisingly, the fuel used is regular gasoline. According to Formula 1 stipulation, it cannot contain any component that is not available in commercial gasoline, but the exact composition can vary subject to strictly defined limits.

As in any sport, cheating is always a possibility and Formula One automobile racing is no exception. In this case, though, it is not only the drivers who have to provide samples to be tested for doping, but their cars as well in the form of gasoline. Contrary to common belief, gasoline is not a single chemical entity, rather it is a complex mixture of compounds derived mostly from petroleum, with smaller amounts of “biofuels” such as ethanol, produced through the fermentation of sugars. There are also various oxygen containing additives designed to boost performance and detergents such as alkylamines and alkyl phosphates to protect the engine from the buildup of sludge.

The first stage of gasoline production begins with distillation of petroleum to capture compounds within a boiling point range that encompasses those having from four to twelve carbon atoms per molecule. Alternatively, higher boiling fractions can be subjected to “catalytic cracking,” causing larger molecules to break down to smaller ones typically found in gasoline.

In an internal combustion engine organic compounds burn to yield carbon dioxide and water vapour, the gases that create the pressure needed to drive the pistons. In reality, combustion is never complete and sometimes the unburned hydrocarbons can autoignite and cause the engine to “knock,” resulting in reduced efficiency. One way to counter this problem is through the edition of lead compounds, a practice that has been phased out because of the metal’s toxicity.

An alternate approach is to reformulate the gasoline by using specific catalysts to rearrange the atoms in some of the molecules to form compounds that burn more efficiently. Benzene, for example, belongs to a family of compounds known as “aromatics” and burns very well, but it is carcinogenic and the amount allowed in gasoline is limited. There is also the possibility of adding compounds from other sources to improve combustion. Ethanol, methanol, methyl-t-butyl ether (MTBE) and ethyl-t-butyl ether (ETBE) are some examples that enhance the efficiency of combustion because of their oxygen content. Ethanol has the added benefit of being made by fermentation of sugars from renewable resources such as corn. Obviously because of the number of compounds possibly present, the variety of blends of gasoline is practically infinite.

In the case of F1 fuel, the composition must comply with strictly defined specifications. The amount of aromatics, olefins (molecules with carbon-carbon double bonds) and compounds containing oxygen are all regulated. There is even a stipulation that a minimum 5.75% of the components must come from a biological source, in other words, not petroleum. Even though the characteristics of the fuel must conform to stringent guidelines, there is still enough maneuvering in exact composition to make a significant difference when it comes to racing.

Before a race each team must provide a sample of the fuel to be used to the sport’s governing body, the International Sports Car Federation (FIA), for analysis by an instrumental technique known as gas chromatography. Another sample, taken at the event also has to be submitted. Each sample is injected into the gas chromatograph with a syringe and is immediately heated and vapourized. An inert carrier gas, usually helium, then pushes the vapours into a column filled with a packing material to which components of the mixture bind to different extents, meaning that they emerge from the column at different times. These “retention” times are characteristic of each component. The exiting gases are electronically detected and translated into a series of peaks on a chart paper with the number of peaks representing the number of compounds detected, and the areas underneath the peaks being proportional to the relative amounts of each component. This output is then compared with one generated by a standard sample of a reference fuel and if the variation is greater than specified by the rules, the fuel is deemed incompliant, and the car may be disqualified.

Chemical manipulation of the drivers can of course also make a difference. Driving one of these machines that pushes technology to the limit is physically and mentally demanding. FIA adheres to the World Anti-Doping Agency’s protocols and drivers are often tested during race weekends. But they may also be subjected to unscheduled tests outside of competitions to ensure they are not using drugs such as steroids to strengthen their muscles, or other performance enhancers. Transgressions are rare.

In case you think F1 racing is a total waste of money, well, not total. The technology developed has resulted in some useful spin-offs ranging from magnetic filters to remove rust from home heating systems to slip-resistant footwear. The telemetry systems that monitor 150,000 measurements a second from over 200 sensors on an F1 car have been adapted to telemetry systems that help researchers monitor a variety of body functions in subjects taking part in clinical trials. Sometimes Formula One is a formula for scientific advancement. Now, if only they could do something about the noise….

 

Joe Schwarcz

A Solution to Skunk Pollution

skunksI remember the first time I ever smelled the fragrance of a skunk.  I thought someone had let off a stink bomb.  You see, even back then I was a lot more familiar with emissions from test tubes than from animals.  This certainly smelled as if someone had mixed sodium sulfide with an acid to release hydrogen sulfide-the classic smell of rotten eggs and stink bombs.  A smell potent enough to quickly drive any living creature away.  Which of course is exactly what the skunk has in mind when it lets loose from the little scent glands on either side of its rectum.

Scientists have long been intrigued by the chemical composition of skunk aroma.  Way back in 1862, the famous German chemist Friedrich Wohler received a gift of “Nordamerikanischen Stinkthiers” fluid from a “freunde in Neuyork.”  It was too smelly for the great man to work with so he gave it to one of his underlings, identified only as Dr. Swarts of Gent.

Swarts carried out the first analysis of skunk secretion and found it to be a complex mixture of many substances which distilled at different temperatures.  He was able to determine, however, that the element sulfur was prevalent in the mixture, making up some 16% of the weight.  There was a price to pay for this enlightenment.  Wohler described that his assistant’s health was adversely affected.  I’ve got to feel sorry for Swarts.  Who knows, maybe he was an ancestor!

Although chemists have been working on the problem of the exact composition of skunk fragrance for over a hundred years, only recently have the specific smelly compounds been identified.  This type of research of course is wrought with difficulty.

First of all, how does one procure a sample?  Very carefully!  Skunks are trapped and anesthetized with ether.  A blunt needle is then inserted into the anal sac of the animal and the contents removed by means of a syringe.  This sample is then subjected to analysis by an instrumental technique known as gas chromatography-mass spectrometry which can separate and identify the components of a mixture.  Literally dozens of compounds have been found in skunk extract with seven having particularly disturbing smells.  Trans-2-butene-1-thiol is the major culprit.

Now that we know this, what good is it?  Obviously, while skunk research may be academically fascinating, what we really want is a solution to the problem of the inquisitive dog or cat that has learned a lesson the hard way about the consequences of skunk chasing.  How can trans-2-butene-1-thiol and its chemical cousins be neutralized?

Tomato juice won’t do it.  That’s a myth.  The only thing tomato juice will do is create a mess, leaving us with the added problem of removing tomato juice from clothing, floors and walls.  It will also turn white dogs pink.

But despair not.  There is a solution.  Thanks to the “Indiglo” watch!  The face of this watch is treated with an electroluminescent material which glows in the dark.  An unfortunate byproduct of the manufacturing process used to make the luminescent substance is hydrogen sulfide.  Not only does this compound smell awful, it is also poisonous.

A materials engineer, Paul Krebaum, working at the plant where the electroluminescent materials were being manufactured developed a process to eliminate the smell.  He designed a system whereby the air was circulated through a solution of concentrated hydrogen peroxide and sodium hydroxide.

This idea was based on some pretty interesting chemistry.  Krebaum knew that sulfur binds quite readily to oxygen and that these “oxidized” derivatives are far less likely to smell.  Experiments showed that an alkaline solution of hydrogen peroxide readily oxidized hydrogen sulfide to odor-free sulfate.  The problem of hydrogen sulfide smell in the plant was solved!

One day, a colleague of Krebaum’s came to work with a woeful tale of an encounter between his dog and a skunk.  Krebaum had never considered the skunk problem before but he knew that the smell contained thiols.  These resembled hydrogen sulfide chemically and should also be oxidized with his reagent!

But you certainly couldn’t expose animals to 30% hydrogen peroxide.  This is dangerous stuff.  So is sodium hydroxide.  The formula had to be modified.  A little experimentation revealed that 3% peroxide would work and the sodium hydroxide could be replaced by baking soda.  Addition of a squirt of dishwashing detergent helped lift the skunk fragrance from the fur.

A magic formula was born: Take one liter of 3% hydrogen peroxide (available in pharmacies), add one quarter cup of baking soda and 1 teaspoon liquid dishwashing detergent.  Wash the cat or dog (or child) with this mixture and rinse with lots of water.  Presto!  The smell is almost completely eliminated.

This latter point is an important one.  People who have struggled with tomato juice and were successful in reducing the smell (no chemical effect, but they probably managed to physically rinse away some of the odiferous compounds) often noted that the scent would come back.

This is because the skunk mixture also contains compounds called thioacetates which are not particularly smelly but over time react with moisture to form thiols.  As the concentration of thiols increases, the skunk aroma returns.  But under the mildly alkaline conditions described in the hydrogen peroxide recipe, these thioacetates are immediately converted to thiols which in turn are oxidized.  Therefore the lingering smell is greatly reduced.

Most researchers of course are interested in eliminating the skunk stench.  But not all.  Skunk smell is known to keep bears away and to also mask the human aroma.  This is of great interest to hunters because their scent can often drive the prey away.

But of course nobody would want to carry around bottles of skunk extract, even if this were available.  The risk of an inadvertent spill would be just too great.  But a clever inventor has come up with a solution.  In fact two solutions!

“Skunk Skreen” comes in two small bottles.  One of them contains a thiol precursor which forms the stinky compound when reacted with the alkaline solution contained in the other bottle.  When desired, a few drops from each bottle are combined on a cloth producing a powerful skunk-like stench.  Bear beware!

As we know, the stench can also keep humans away.  Which is what an Alaskan inventor had in mind when he patented his “personal protector” based on skunk smell.  There is of course no time to start combining chemicals when someone is accosted so he designed a system whereby the skunk extract is enclosed in capsules which are incorporated into a credit card.  In an emergency, the card is pointed at the attacker and is bent, squirting a stream of foul scented liquid.  The card is smooth on one side and rough on the other to avoid any accidental self-spraying.

Sounds good.  Presumably the police would have little trouble tracking the culprit as the smell would linger for weeks.  That is unless the criminal knows how you have to mix hydrogen peroxide with baking soda and detergent to get the right chemistry!

Joe Schwarcz

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