The Chemistry of War: Non Lethal Weapons Tear Gas

an entry by Mika Thomas, Helen Sakharova, Ko Cheng Chan

Figure 1: A Us soldier wearing a gas mask while traveling through a field filled with tear gas during a training drill

The human body is wonderfully capable of quickly responding to its environment.  Different substances trigger different reaction in the human body.  Tear gas, or a lachrymator, is a substance that interacts violently with the mucosal membranes such as the eyes, mouth, nose and lungs.  Tear gas is actually not a gas, but a colloid, more specifically, an aerosol.  The chemical structure of tear gas is what causes it to affect us differently than other substances.

    Pepper spray also applies to the definition of a tear gas however, unlike CN gas, it is considered an inflammatory agent.  Pepper spray causes painful swelling of capillaries in the eyes and caused temporary blindness.   Pepper spray is relatively simple compared to CN and CS gases.  As the name would suggest, it is derived from peppers.  Peppers contain a group of chemicals called capsaicin.  Pepper spray is also referred to as OC spray, Oleoresin Capsicum spray.  A capsaicin is a colorless irritating phenolic amide C18H27NO3  and is responsible for giving peppers their pungent spicy flavor.  Capsaicins’ molecular structure enable them to bind directly with proteins found in the membranes of pain sensing neurons.   This causes a victim to feel an intense burning sensation, excess salivation, excess mucous production, and even vomiting.  Therefore, pepper spray should be used wisely.   The difference between sweet peppers and the infamously painful ghost pepper is the concentration of capsaicin that they both contain.

This concept of concentration also plays strongly into the potency of pepper sprays and tear gases.  Different states have different laws on the limit of capsaicin that can be used for personal protection.  Even so, for almost all pepper sprays, a 1 second blast can render a person incapacitated for fifteen minutes to an hour. Different brands of pepper spray contain different amounts of solvents such as alcohols, and water.   The more dilute the concentration of capsaicin, the less potent the spray will be.  Like other forms of tear gas, pepper spray is canned under extremely high pressures and this results in an average can of pepper spray having a shooting range of about 10 feet.  More application differences between CN gas and pepper spray can be read about here.

Figure 2 : an image of a molecule of capsaicin.  The black balls represent carbon atoms, the white balls represent hydrogen atoms, the blue ball represents an atom of nitrogen and the red balls represent oxygen atoms.

    Tear gas is qualified as a nonlethal weapon, but there are serious risks involved.  Tear gases qualify as a type of chemical warfare and are prohibited in war by many international warfare treaties.  However, tear gases are allowed to be used by branches of the military for training.  Tear gases are use used normally for domestic riot control or personal protection.    CN (chloroacetophenone) gas, CS (chlorobenzylidenemalononitrile)) gas and bromoacetone are the types of tear gases used by law enforcement.  A familiar form of CN gas is Mace, a popular trademark brand of CN gas sold for personal protection.

    CS gas is normally composed of a white powder mixed in a dispersal agent like methylene chloride. At standard temperature and pressure, CS forms a white crystal with a low vapour pressure and poor solubility.  CS crystals are converted into microparticulate clouds by pyrotechnic devices.  CS gas may seem to be a continuous solution or a gas, but it is also a colloid.

Figure 3: An image of a Us soldier wearing a gas mask to avoid the painful, yet temporary effects of CS gas. CS gas appears to be a white gas, but it is composed of small particles of white solid.

    As a result, CS gas is usually stored in cans at high pressures. A can of CS contains a gas and skin irritating solvents. When this can is used, highly pressurized gas escapes a can and the gas carries ultra-fine particles of CS.  The powdered CS becomes attached to the mucous membranes of organisms. The physical effects of CS gas is felt almost immediately.  A person’s breathing rate slows and excessive use of CS gas can lead to death. The poor solubility of CS makes it that it can exist on a mucous membrane for a long period of time if not physically removed.  Luckily, wind and fresh air can removed CS particles from the skin.  Gas masks work by protecting ones mucous membranes.

    Because it has been dubbed a nonlethal weapon there is fear that authoritative forces use it too liberally.    Tear gas is technically a “less-than-lethal” weapon because it can, in some cases, lead to death.  There is controversy over allowing authoritative forces to use tear gas.  Often, law enforcers must be exposed to tear gas themselves before they gain the right to use it.  While the memory f the pain of peppery spray might stop a young officer from using it too much, an older officer might not remember the pain and use it too often.  CN gas is excruciatingly painful and is often used on protesters as shown below.  The use of tear gas has raised social controversy that has even inspired for scientific research to be conducted on tear gases.  

The Chemistry of Cannabis: Detection of Cannabis Farms

*This blog post is purely for educational purposes. We do not support the production, distribution, or consumption of Cannabis.

Welcome back! So, since you’ve clearly been overwhelmed by the amazingness of the information in our blog posts, we think you deserve a refresher. In previous blog posts, we have discussed the effects thatCannabis has on the brain, and the different forms through which Cannabis can enter the body and results in these effects. In this blog post, we’ll discuss new and innovative ways that law enforcement is using to detect Cannabis farms.

Scratch ‘N Sniff™

(yes, you read that right)

A charity organization based in London, England has come up with an innovative way to help police officers locate Cannabis farms. The organization has created Scratch ‘N Sniff™ cards. These Scratch ‘N Sniff™ cards that mimic the scent of Cannabis in its growing stage, and are being distributed to English citizens so that they can to familiarize themselves with the smell of growing Cannabis and can notify the police if they detect the scent. So far, the organization has issued more than 200,000 scratch and sniff cards to hotspots in England, and, there has been a 28% increase in information from the public on Cannabis farms.

Now, how do these Scratch ‘N Sniff™ cards work? The ideas of chemistry can be applied to the Scratch ‘N Sniff™ technology through the ideas associated with entropy. Entropy is the number of ways a system can be arranged. In this case, aroma molecules that are microencapsulated are at a state of low entropy, since they are enclosed in minute capsules. The manufacturing process of scratch and sniff cards utilizes this entropy idea. The diagram shown below illustrates the process. In general, the process includes taking the aroma-generating chemical and encapsulating it in gelatin or plastic spheres that are a few microns in diameter, and this traps the odor. A certain chemical catalyst is used to bring about the reaction which finalizes the encapsulation of the odor. In other words, the catalyst is the metaphorical “kick in the pants,” or the thing that bring about the reaction. This  reaction requires a “kick in the pants” because it will not happen on its own; this type of reaction prevents particles from diffusing, as they would “like” to, and in order to get particles to do something they don’t want to, you have to bribe them with energy.

When these capsules are given another metaphorical “kick in the pants,” or an activation energy, they are released and they dissipate and spread the scent. Even though the particles want to diffuse, a “kick in the pants” is required to give them enough energy to break through the capsule. This energy required to get this reaction going comes in the form of kinetic energy from a person, when he/she scratches the card, applying friction to the capsules. The aroma molecules are then released, and since they have more volume to diffuse into, they achieve a higher state of entropy.

This idea of  Scratch ‘N Sniff™ technology, then, can support the notion that the entropy of the universe is always increasing. Spontaneous reactions, which have a negative free energy value, are constantly occurring in the universe. The Scratch ‘N Sniff™ system is one primary example of this chemical theory. Since this technology embodies the principles underlying entropy, then it also applies to The Second Law of Thermodynamics. This law states that “In an isolated system, natural processes are spontaneous when they lead to an increase in disorder, or entropy.”

Thermal Cameras

Authorities are beginning to use thermal cameras to detectCannabis farms. Often, Cannabis growers employ heat lamps when growing indoors. Further modifications to the growing area typically include the addition of ventilation and irrigation systems. Thermal cameras are being used to detect growers who hideCannabis around other plants, rendering them invisible to the naked eye. However, the grower must make some changes to the soil, which allow these cameras to detect hidden plants. The soil is turned over and the vegetation around the plant is trimmed off to allow for better absorption of water and nutrients. As a result the soil also absorbs heat at a higher rate than the other surrounding plants. Consequently, they stand out in thermal scans.

Just like any other camera you use, thermal cameras detect light. However, they differ from conventional cameras in that they detect different wavelengths of light. Thermal cameras detect infrared light as opposed to visible light. Because the lamps generate heat, the system emits infrared radiation. At the atomic level, the heat is simply the movement of particles. When the particles collide with each other, they can affect each other and induce a dipole oscillation. Due to this volatile distribution of charge, electric and magnetic waves are emitted as photons within a certain range of frequencies. Finally, the hotter an object is, the shorter the wavelength it emits. Thus, thermal cameras display hotter areas closer to white and darker areas closer to black. Also, if an object is hot enough it can emit thermal radiation that is visible to the human eye, a simple example being fire.

Well, that’s all folks!

Sherlocked: Unlocking the Chemical Mystery

We’ve all heard the story of Hansel and Gretel- kids abandoned in the woods encounter a delectable house made of candy, meet an evil witch in the candy house, and get captured and force- fed sweets by the said cannibalistic witch so that she can inevitably gobble up the children. Luckily, the protagonists in this classic fable survive when they push the witch into the very oven she was planning to cook them in, and it’s a happily ever after for everyone (except the witch).

In our case, though, there is no convenient oven to trap the witch in- or rather, the criminal mastermind. Indeed, we have chosen to analyze a scene from the modern- day British television crime drama, Sherlock. A contemporary adaptation of Sir Arthur Conan Doyle’s classic detective stories, the show integrates modern forensic techniques to showcase Sherlock’s incredible skills of deduction in a more realistic light. But what does this have anything to do with a classic German fairy tale?

In a scene from the episode, The Reichenbach Fall, we see Sherlock investigating a case of children gone missing- vanished from their beds. Although seemingly stumped at first, he soon realizes that one of the kidnapped children, having a predilection for spy books, was clever enough to leave behind a trail of linseed oil, which supposedly exhibits fluorescence under the presence of ultraviolet light. Sherlock then takes a scraping of the footprints the kidnapper left by stepping in the spilled oil and analyzes the traces left behind in the oil to determine his precise location. The examination leads him directly to a chocolate factory, where the children had been driven dangerously ill by eating copious amounts of candy and were on the verge of dying in the arson of the factory. Sound familiar?

The kidnapper is the “consulting criminal” Moriarty, a man who acts as a consultant to commit crimes for his clients. He is also Sherlock’s primary rival in the show and the antithesis of Sherlock’s “consulting detective” position. He is clearly establishing the Hansel and Gretel motif here intentionally, being that the kidnapped siblings were German, left behind by their parents over term break and taken to a place where they nearly meet their doom through burning. It’s undoubtedly a relief that the ingenuity of the child paired with Sherlock’s observance saved the victims, but the modernistic juxtaposition of the series makes us consider the unavoidable question: what if this hadn’t been just a plot event in a fictional series? What if it were real? Simply shining a special light over the crime scene to reveal the answer seems a tad too easy to be true. Does linseed oil indeed show itself under UV light? If so, can this behavior be explained chemically?

Figure 1. Structure of linseed oil, comprised of polyunsaturated fatty acids and ester bonds.

As it turns out, linseed oil is a triglyceride capable of fluorescence after degradation when exposed to UV light. Derived from the seeds of a flax plant, linseed oil is fatty oil that contains polyunsaturated fatty acids. It is commonly called a drying oil, because when exposed to oxygen in the air, it undergoes a process known as polymerization, or drying. This is partly due to its composition – it contains an unusually high amount of alpha-linolenic acid as well as di- and triunsaturated esters, which makes linseed oil inclined to polymerize when brought into contact with atmospheric oxygen. This autoxidation, the exothermic addition of oxygen to an organic compound, causes subsequent crosslinking and the curing of oils. An atmospheric oxygen molecule in the air immediately pounces on the long hydrocarbon chains of the oil’s fatty acids, inserting itself into carbon- hydrogen bonds adjacent to one of the double bonds within the unsaturated fatty acid. This causes a domino effect in which a number of addition reactions, organic reactions in which two or more molecules combine to form a larger one, occurs in rapid succession. This in turn forms hydroperoxides that are susceptible to crosslinking reactions. A vast polymer network forms as a result of the bonds between neighboring fatty acid chains, and is visible as a skin-like film formation on samples. The polymer network may undergo further change over time; it can transition from a system held together by nonpolar covalent bonds to one governed by ionic forces between the functional groups as well as the metal ions present in the paint pigment. This change is primarily due to the functional groups in the network becoming ionized. Moreover, the eventual polymerization process results in rigid, somewhat elastic films that do not readily flow or deform. The early stages of polymerization can be monitored by changes in weight; linseed oil in particular increases in weight by 17 percent as the reaction occurs. With regard to linseed oil, its structure becomes a huge, chain-like polymer network of molecules, as shown below in Figure 2. As a result of this process, free radicals are produced. Free radicals are substances containing an unpaired electron, which makes it highly reactive. More addition reactions ensue, each step producing additional free radicals. They continue to engage in polymerization until all the free radicals have collided and  their unpaired reactions have been combined to form a new bond, at which point the reaction halts. The polymerisation stage occurs over a period of days to weeks, rendering the film dry to the touch.

Figure 2. Linseed oil undergoes polymerization to form a huge, chain-like polymer network of molecules.

 Fluorescence is generally characterized by the presence of aromatic compounds and their delocalized electrons. In organic chemistry, aromaticity is a property of conjugated cycloalkenes whose p-orbital electrons are delocalized and provide a framework for a stable and planar molecule. Typically, fluorescent compounds will be highly conjugated. In addition, it is well established that these fluoresce when exposed to ultraviolet light as shown in Sherlock.  When a vegetable oil, such as linseed oil, is heated, its fluorescence is initially diminished and indiscernible due to the decomposition products and nitromethane, but as the oil progressively becomes polymerized, its fluorescence increases in intensity. In the episode The Reichenbach Fall, Sherlock did not heat the linseed oil, but instead the oil simply revealed itself under the presence of UV light.

Figure 3. When electrons of a substance absorb energy gained from UV light, they are excited to higher energy levels and then fall back to their ground states, emitting energy in the form of light. Fluorescence is light emitted that is in the visible spectrum.

In order to be fluorescent, a molecule must be highly absorbing, and possess the appropriate structure andelectronic energy levels. Fluorescence occurs when electrons absorb energy from the UV light to become excited to a higher energy level. When these electrons come back to the ground state, energy is emitted in a form of a light. Because the light that is emitted usually has a longer wavelength than the energy absorbed, we are able to see the light emitted as fluorescence. This is due to something known as the Stokes’ Shift in which a molecule that absorbed light is now in the excited state releases a bit of the initial energy first before releasing the rest of the energy in the form of a weaker proton to get back to the ground state. Linseed oil is able to exhibit fluorescence because of both the chemical and physical properties that it has. As stated before, linseed oil contains many fatty acids. Some of these fatty acids contain pi bonds which are very good at absorbing and emitting light. This is due to the fact that the energy separation for an isolated pi bond is very large, and so the ultraviolet light with its large energy and short wavelength can excite the electrons in the pi bond.  However, linseed oil does not fluoresce brightly because linseed oil does not contain conjugated pi systems (a system in which double bonds alternate with single bonds).

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Figure 4. The Stokes’ Shift occurs when an excited molecule releases some of the initial energy before releasing the remainder of the energy in form of a weaker proton to return to the ground state. This allows us to view the light emitted as fluorescence.

We thought this investigation seemed a tad too easy  to be 100% chemically accurate, and we were correct- partially, at least. As discussed above, linseed oil does in fact dry into a somewhat elastic film through a process termed polymerization- however, the entire affair can range time- wise from several days to weeks, indicating that by the time Sherlock and Watson had arrived at the scene, the state of the oil most likely would not have sufficed for UV testing. Moreover, linseed oil’s fluorescent properties are significantly less notable than that of conjugated pi system- containing compounds, the light emitted being of longer wavelength and weaker energy than that absorbed. And now for the final kicker- dried linseed oil barely exhibits any fluorescence under UV light than it does as a viscous liquid. The non conjugated system in the oil compound has its double bonds broken when dried, thus notably lessening the already minimal degree to which the substance fluoresces; no question that it certainly would not have glowed with the same quality of brilliant luminescence as it did in the scene. Nonetheless, we applaud the Sherlock forensics team, whoever they are, on their ingenuity on thinking to use a drying oil as a means of tracing a kidnapping to parallel the trail found in Hansel and Gretel. Though it might not have worked in reality, we also know that  bending the truth is sometimes necessary on the screen- and this definitely receives full marks for originality!

KNO3 the Chemistry Behind the Boom

It comes as no big surprise that action films and explosions go hand-in-hand. As most of us have likely experienced, utter obliteration on the silver screen conveys a sense of immediate gratification that other movie-made special effects have trouble measuring up to. In this post, we embrace our inner ten- year old selves and delve into the hugely esoteric field of things going boom. It’s always nice to see the crux of a fast- paced film relate to something other than gunshots and arbitrary detonations, and 21 Jump Street puts forth a noteworthy effort to align a little sense in their big finish. We’d tell you ourselves, but Channing Tatum really said it best in this excerpt from the movie:

“Potassium Nitrate-

Don’t hate.

It’s great.

It can act as an oxidizer.

I didn’t know that,

but now I’m wiser.

It has a crystalline structure.

If you can’t respect that,

you’re a butt-muncher.

It’s a key ingredient in gunpowder.

K-No-Three!”

Tatum plays Jenko, a jock- turned- police officer who goes undercover when assigned to infiltrate a high school in his special police unit. Jenko’s course is switched with that of Schmidt, his brainy partner in crime (or justice), and subsequently is forced to suffer through an AP Chemistry course. His progressive appreciation for the subject pays off, however, when Jenko is able to utilize the knowledge he gained to blow up the limo of a drug dealer in the final chase scene with the creation of an impromptu battery bomb composed of a tequila, potassium nitrate (from shotgun shells) and lithium (from lithium batteries of a camera). Would this concoction have produced the earth-shaking explosion it did?

Lithium batteries and tequila would have produced the exothermic single displacement reaction  Li (s) + H2O (l) → LiOH (aq) +H2 (g). When lithium comes into contact with water a violent reaction occurs, resulting in the release of hydrogen gas inside the tequila bottle, since lithium is higher up in the reactivity series than hydrogen gas due to lithium’s single valence electron in its 2s1 orbital. Furthermore, alcohol is highly flammable and will combust with the hydrogen gas if there is sufficient heat. When Jenko agitated the solution by shaking the bottle, the reaction released the necessary activation energy to combust hydrogen gas and alcohol. Said combustion reaction, 2 H2(g) + O2 (g) → 2 H2O (l), has its oxygen gas provided by the oxidizing agent KNO3.

While the theoretical portion of this analysis has been relatively accurate, the tendency of hollywood to exaggerate now comes into play. Once Jenko placed the lithium inside the bottle, the reaction should have occurred almost instantly with the near immediate release of hydrogen gas, exploding before the bottle left his hands.  Instead, there is a considerable amount of lapse before Jenko throws the battery bomb. As with any reaction, the rate at which the reaction occurs depends on the required amount of activation energy. In this case, the activation energy required to produce the combustion reaction should have been generated from the exothermic reaction between lithium and water. This combined with the shaking of the bottle ultimately would result in the explosion occurring right away. Thus, although the explosion was reasonably designed, its timing was not necessarily as realistic. Moreover, the size of the explosion in the scene is inordinately exaggerated; the use of lithium would not have produced destruction anywhere near that degree. Rather, it would have been more suitable to have used an alkali metal with a more reactive potential in place of lithium to produce an explosion closer to the magnitude of the one shown on the movie screen.

All in all, screenwriter Michael Bacall’s incorporation of chemistry into an action flick wins high points for creativity, but falls under the standard on the scale of realism. Even Bacall himself acknowledges that in hindsight, he should have “talked to an actual chemist” instead of relying on his fading knowledge back from his own AP chemistry class back in high school. Still, his enthusiasm to portray chemistry as the climatic solution to the problem in the movie is applaudable and exciting.

Methamphetamine: Crystal Clear Chemistry

Breaking Bad is the show that portrays the dangerous relationship between people and the addictive effects of methamphetamine, commonly dubbed meth. While it does an excellent job at captivating and developing a rich fictional world, it does not detail the actual chemistry of the crystal substance. After discussing the production of methamphetamine in the previous post, it is necessary to communicate the chemistry related to it. In a style similar to the information presented on morphine, let’s dive into the world of the methamphetamine molecule.

Mirrored Isomers: Structure and Function

Methamphetamine is considered a member of the phenethylamine family, which is generally consisted of psycho-stimulants. N-methyl-1-phenyl-propan-2-amine, according to its IUPAC labeling, has two isomers that produce distinct effects based on the particular structural isomer. There is a peculiarity regarding these isomers because they are simply mirror images of each other. It may seem as though they are the same molecule, but because orientation is a large factor in some chemical and physiological processes, there is a significant enough difference to give these types of mirrored isomers a special name: enantiomers.

The two enantiomers are named after a property observed in the polarization of light. The dextrorotatory isomer is the widely known, heavily abused substance that stimulates psycho-activity. The mirrored molecule is the levorotatory isomer, known for its use in decongestants and inhalers. The logic behind this naming system lies with the fact that the enantiomers are what are known as chiral molecules. Put simply, chiral molecules represent the disparity between the left and right hand. One cannot be successfully superimposed on the other and be expected to be identical. The diagram below can be used to visualize the concept. This property of chirality is what gives compounds like these the property ofoptical activity. Although a bit convoluted, the naming reflects the ability of the molecule to turn the plane of the polarized light toward the direction of the motion.

Use the image above to visualize why enantiomers are actually two different compounds rather than just one molecule being mirrored.

A sample of produced methamphetamine will likely contain both enantiomers depending on which cooking process is used. Due to both being present, there is an optical inactivity of the mixture, meaning that the degree of rotation of the polarized light due to the dextrorotatory isomer is being cancelled by the levorotatory isomer since they both rotate light by the same degree, but in opposite directions. Therefore, the cooks of the illegal d-amphetamine aim to create the purest meth consisted of only the dextrorotatory isomer and none of the other enantiomer. It would then be considered enantiomerically pure and be optically active in one direction.

         The image above displays a 3D model of C10H15N, methamphetamine. See below for information about the isomers.

 The Structure, Properties, and Look of Methamphetamine

The structure includes a carbon ring, two methyl groups, and a secondary amine. The phenyl ring and methyl groups are basic functional groups that are present in a wide variety of organic molecules. However, the secondary amine is not as common. In general, an amine is consisted of at least one nitrogen atom with a lone pair. Being named a secondary amine means that it is bonded to two organic substituents and one hydrogen, so in this case, one substituent is the chain of carbons and the other is a methyl group. This amine groups makes it so that a saturated solution in water is considered alkaline by litmus paper. How does this all look on the macroscopic level?

The image above displays the crystalline structure of a sample of crystal meth. Note the transparency and the cloudy white that serve as indications toward purity.

Meth retains a crystalline structure, even in the form of a white powder, caused by the ordered placement of atoms in a particular, rigid structure. As apparent in the picture above, the crystals may seem impure due to the cloudy white color, but this is not the case. The method of the creation of methamphetamine, as discussed in the previous post, results in the creation of a racemic mixture. The crystallization of the racemic mixture, which is what the impure product of methamphetamine production will usually be, can occur in a number of different ways. If the product is impure and thus contains both enantiomers, then it will crystallized into what is known as a quasiracemate, the mixture of two similar but directionally distinct compounds. Typically, when the product is pure, it will crystallize into a racemic conglomerate. This is where molecules in the structure have a strong attraction to the same enantiomer, rather than the opposite one. Without regards to the crystallization of the chemical, purity is judged simply by how white or clear a sample is. Keeping in mind that the color white represents the physical reflection of all wavelengths of visible light, it then makes sense that when the sample is colored white, there is an indication of high quality purity. Impurities would cause some wavelengths to be absorbed, causing some coloration of the crystals.

In Your Head

Once consumed, meth increases the production of dopamine and halts its reuptake. The goal is to, therefore, create an excess amount of dopamine in the brain and keep it there. Behind this manipulation is the fact that d-methamphetamine, the psychoactive isomer of the two, is physically similar to dopamine. Neurons communicate by sending neurotransmitters, like dopamine, across the synapse, the gap, between the two. Meth acts in a way that the neuron will accept it as though it were dopamine. However, it can also target neurons that transmit serotonin and norepinephrine, chemicals similar to dopamine. Inside the neuron, methamphetamine can change its function, resulting in a variety of psychological changes. Through studies and research, the National Institutes of Health (NIH) have found that it interferes with verbal learning and motor skills as well as emotion and memory, leading to emotional and cognitive difficulties. Recovering from abuse involves many steps and factors that deal with the emotional, physical, and behavioral damage.

Regardless of the dangers that are presented about methamphetamine, it is necessary to remember that only one of the two is widely abused, yet both are still used in some medications. When used in the correct dosages, the harmful effects towards the neurons that were described above could very well be turned into a benefit. The portrayal of these drugs often makes them seem exactly the same, especially considering that many of them are psychostimulants and abused. However, with the intricacies of the chemistry, it is evident that there is much more to the story. Throughout the series of these five blog posts, the objective has been to gain some familiarity with a couple of the demonized analgesics. By introducing how they are made and the chemistry behind them, it is hoped that the generalizations about their use have been eliminated, as well as the prominent perspective that these can only be negative towards the user of such compounds. A spectrum of chemistry topics were incorporated and discussed to provide information that can be carried on and applied to many more topics elsewhere. Even though people should be wary towards the consistent use of such powerful drugs as methamphetamines, morphine, codeine, and the other derivatives, there is always two side to a coin.

“Mething” With Your Health

Introduction

Like the drug morphine, which we discussed earlier, taking methamphetamine (pictured above) also causes dopamine to be released in the brain. It also can cause a dependence in a similar manner, requiring more methamphetamine in order to produce the same effect if it’s constantly consumed. However, unlike morphine, methamphetamine does not have medical uses as an analgesic. In addition to this, methamphetamine cannot be manufactured using the sap from an opium poppy. Instead, it uses something that is considerably more accessible to people all around the country.

Ingredients

  

The first image is a sample of iodine, an essential ingredient in the production of methamphetamine. The second image shows red phosphorus in action, helping to light a match. The match itself does not contain red phosphorus, but the surface it’s being struck against  does. Purchasing matchboxes for the sole purpose of extracting red phosphorus is cost inefficient. Cold medications such as Sudafed can contain ephedrine or pseudoephedrine as an active ingredient, as shown in the third image.

The primary ingredients used in making methamphetamine are ephedrine or pseudoephedrine (which can be found in common cold medicines such as Sudafed), iodine crystals, and red phosphorus from matchbooks. Secondary ingredients, used in processing the meth, include petroleum fuel, hydrochloric acid, acetone, methanol, and sodium hydroxide solution. Other chemicals can be used to act as filler, weakening the meth’s effects and adding to the weight of the product of the meth production. These filler chemicals include lithium hydride, ether, Freon (a chlorofluorocarbon or CFC), ammonia, sulfuric and acetic acid, benzyl chloride, lead and mercuric chloride, and even laxatives. When synthesizing these ingredients in a lab, they can be retrieved in sealed containers, but when synthesizing these ingredients at home, more dangerous methods must be used since the license to get these chemicals is nonexistent. As an example, homemade meth relies on unwinding a lithium battery to obtain the lithium filler.  This video shows this process.

“Organized” Production

Depicted here is a meth lab with stations for crushing ephedrine tablets, combining iodine crystals and red phosphorus, adding sodium hydroxide and a CFC, and bubbling gaseous hydrogen chloride through liquid meth.

Methamphetamine produced in superlabs makes up 80% of the supply of meth in the United States, with these superlabs being operated by drug cartels. The production of meth in a superlab is much more involved than the production of meth at home. First, the ephedrine tablets are ground into a powder. Then, this powder is placed in the methanol, allowing the actual ephedrine to separate from the filler material in the ephedrine tablets. The filler material in the tablets (which does not get dissolved in the methanol) is then filtered out, and the remaining solution is boiled to leave pure ephedrine. The iodine crystals are reacted with the red phosphorus in water to make hydroiodic acid, and the pure ephedrine is added to the heated hydroiodic acid to produce an acidic solution of methamphetamine and red phosphorus that isn’t dissolved. The remnants of the red phosphorus are filtered by passing the whole solution through a porous filter, leaving just the acidic solution of methamphetamine. A solution of sodium hydroxide is added to this solution to make it more neutral. A chlorofluorocarbon is added to the resultant solution to precipitate out the methamphetamine in liquid form, which is denser than water. Thus, the methamphetamine can be collected by extracting it from the bottom of the container it’s in. Gaseous hydrogen chloride is bubbled through the liquid methamphetamine to turn it into a wet salt. Once this salt is dried by filtering it from the water, it is able to be consumed. Like it was mentioned before, however, fillers are added to this meth product to lessen its effects and make it appear that more is produced.

Risks of Meth Production

Interestingly enough, the ingredients used to make methamphetamine can be extremely harmful to ingest by themselves. When taken in high doses, iodine can damage the thyroid, which releases hormones into the body. Sodium hydroxide can be used to loosen up the clogs in drains, and it can even be used to dissolve road kill as part of highway cleanup. Hydrogen chloride, is also corrosive and if a screw-up occurs when bubbling it through the liquid meth, it can result in bodily harm. The ether used as filler is flammable and can cause drowsiness or unconsciousness if its fumes are inhaled, so the final processing of the methamphetamine can be hazardous to one’s health if he or she is not careful. This risk is compounded by the fact that large amounts of chemicals are used to produce meager amounts of consumable methamphetamine (like 4 boxes of matches are used to get enough red phosphorus to make 2 to 3 grams of meth).

Do-it-Yourself Method of Meth Production

Here is an image of the equipment needed to produce methamphetamine via the shake-and-bake method. The green, plastic bottle located towards the middle is what contains the reaction of the different ingredients.

The previous method of meth production occurs in labs where safety precautions may be in place, but there are methods to produce methamphetamine at home using ingredients that are just as dangerous. A popular method to produce meth at home is known as the shake-and-bake method. The apparatus used for this method is a sealed bottle that one must add the ingredients to and shake. These ingredients include ephedrine or pseudoephedrine, lithium, ammonium nitrate, sodium hydroxide, water, and petroleum fuel. The basic method is to throw them all into a bottle, cap it, and swirl it around. The reactions that occur, however, generate pressure that must be first kept inside the bottle to produce enough yield. When the lithium starts shriveling and changing color, some pressure must be released because the bottle will explode otherwise, scattering harmful chemicals everywhere. Since the producer of the meth is in contact with the bottle as the reactions are occurring, this can cause severe bodily harm. In addition to this, once a methamphetamine precipitate forms, gaseous hydrogen chloride must be added to it before it can be consumed. It should go without saying that this also puts the methmaker in danger.

Conclusion

Cooking meth is a dangerous process that can cause harm to the producer if he or she is careless about the different chemicals that are being handled. Despite all the harmful ingredients that go into the process of making methamphetamine, the final product is able to be consumed without experiencing much damage to the digestive system. This is, in part, because of its chemical structure, which we will cover in the next blog post.

Decoded: Hidden Message in National Treasure

We hold these truths to be self- evident, that all movies are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty, and the pursuit of chemical accuracy. Sound familiar?

Admittedly, the above is a somewhat altered excerpt from the one and only Declaration of Independence, and although it might have been tweaked just a tad, the message conveyed is clear nevertheless. We’ve managed to come across a particular scene in the film National Treasure – one that will make experts cringe and bring any respectable curator to shudder at this seemingly harmless mistake.

In the scene, actor Nicolas Cage and his partner in crime, actress Diane Kruger, bend apprehensively over the Declaration of Independence. They are trying to decode what they think is a 300-year-old hidden message written in invisible ink. Their way of going about this is critical- at least in the realistic sense. In the movie, Kruger simply rubs a q- tip across the citric surface of a sliced lemon and slides it across the paper, almost magically revealing words. Disposed of their duty to scientific precision, the film then quickly moves on to take care of more pressing matters. However, what is not disclosed along with the decoded message is the fact that the utilized technique would most likely have permanently damaged the priceless document with its crude detail. Why? Just what is this key idea that can make or break such a scene? Our answer lies in the chemical process of oxidation and caramelization.

For those not in the know, invisible ink, also known as security ink, is a unique substance used for writing. Although invisible upon application, visibility can be induced by a specific set of physical changes or chemical reactions, most of which are simple enough to be performed using common household materials. Its purpose makes invisible ink a common target of espionage, property marking, hand stamping, anti-counterfeiting, and, in this case, common identification.

In general, the types of invisible inks can be categorized into three kinds: those developed by heat, those developed by light, and those developed by chemical reactions. Lemon juice, as used in the scene,  turns paper light blue when sprayed with iodine and turns the paper brown when exposed to heat. Because there are too many indicators that would reveal the lemon juice,  lemon juice is not often used as invisible ink in real life by spies.

Lemon juice is initially not visible to the naked eye because it is composed of sugar, water, and citric acid. None of these components contain much color, and thus they appear “invisible” after the lemon juice dries on paper. The citric acid also inhibits the oxidation of the other components, like lemon, thus preventing the lemon bits from browning. However, the lemon juice can be made visible by the process of heating, which causes the citric acid to decompose and the lemon bits to consequently become oxidized. Oxidation reactions involve the loss of electrons from the species, or the increase in oxidation state by a molecule, atom, or ion.

 The following diagrams illustrate the degradation of cellulose fiber, found in paper, by an acid. The glucose units in the cellulose chain are broken down by hydrogen ions from the citric acid, leaving one side of the unit stable while the other seeks to bind with a water molecule. This sets off a repeated cycle that continuously weakens the fibers in the paper. This breaks down said fibers into sugars, allowing the weakened part of the paper to burn faster and with more ease when exposed to heat, therefore allowing for the process of caramelization to occur.

The process of caramelization, which is the oxidation of sugar, is also implicated in the ‘secret’ behind invisible lemon juice ink. It begins, once again, with the heating of the paper on which the message is written. Paper, which contains  cellulose fibers, burns with ease and browns quickly. Lemon juice, however, contains acid that weakens the components of paper and breaks down the cellulose fibers in the paper into sugars, which accelerates the reaction of burning and browning.

When heat caramelizes the carbon-based sugars, they turn brown because when the carbon comes into contact with the air, it oxidizes. As a result, the part of the paper with lemon juice on it burns and browns more quickly than the rest of the paper, revealing the invisible message. In fact, if a piece of paper saturated with lemon juice were to be left alone, it would eventually become brown; heating simply speeds up the process.

What was wrong with National Treasure?

In this scene, lemon juice is utilized as the indicator, or the developer, that would reveal the message. In some cases, invisible inks can be made visible using acids or bases. The most common example of this would be phenolphthalein, an indicator that turns a bright pink hue when exposed to ammonia fumes. However, organic acids such as lemon juice are primarily the invisible inks themselves, made visible by the oxidation reaction initiated by the introduction of heat to the acid. National Treasure’s mistake lies in its choice of technique; rather than using lemon juice as either an indicator or an ink, it mixed and matched various parts of different methods to form one big conglomeration. In the film, the team spreads lemon juice over the document, and uses their own breath to supply the heat to reveal the words. Needless to say, this would not have sufficed to produce the subsequent reaction that would turn the juice brown. Later they use a hair dryer instead, which is better, but still not ideal. Still, the main issue lies within the usage of the juice as a developer to reveal the hidden message and then heating- all that would have achieved in reality would be to oxidize the juice covering up all the secret writing, thus rendering the code irretrievable and damaging the document.

Arsenic – The King of Poisons

Poison is perhaps a practical, if not cowardly, method of murdering people. The reason a person would choose to use poison is because they do not like confrontation. However, poison is often overlooked when considering the death of a person because even small doses can be fatal. This is why poisoners often get away with murder. Arsenic is known as the “King of Poisons” and its history started with Paracelsus, the father of modern toxicology. Arsenic is an ideal poison because it is colorless, odorless, and tasteless and is easily dissolvable in water.

Effects of Arsenic

A dose of 5 mg m^-3 of arsenic is lethal when ingested. Pure arsenic is actually less dangerous than compounds of arsenic because the human body does not readily absorb the element. As₂O₃ and AsH₃ on the other hand are compounds that are absorbed easily. Symptoms that occur when exposed to toxic levels of arsenic include vomiting, abdominal pain, diarrhea, dehydration, vertigo, delirium, and shock.

Arsenic is disruptive to the processes in the body that produce ATP. This is because arsenate, which closely resembles phosphate, can mistakenly displace phosphate in enzymes. Phosphate is used as energy by cells so replacing arsenate limits the energy being transported to the cells in the human body. By upsetting the cellular pathways of ATP, the neurological and cardiovascular systems become messed up too. Also, arsenic likes to bind to sulfur that are needed in enzymes involved in metabolism, but when it does it ruins that enzyme’s ability to function normally.

Arsenic also varies in toxicity depending on the form of arsenic. Arsenic is commonly found as arsenic (+5) or arsenic (+3). When arsenic combines with other elements like sulfur, oxygen, and chlorine it forms inorganic compounds. If it binds with carbon, an organic compound is created. Generally, inorganic compounds of arsenic are considered more poisonous because they are more unstable.

Arsenic in Crimes

A newspaper journalist, Frank McKinney Hubbard, once said “when you consider what chance women have to poison their husbands, it’s a wonder there isn’t more of it done”. It is a common misconception that poisoners are mainly women but this is not the case. There are many infamous murders committed with arsenic: the Borgias family during the Italian Renaissance, Mary Ann Cotton, and Madame Giulia Toffana to name a few.

Detection of Arsenic

Poisoning was much more prevalent when there were no methods for detecting them in the human body. Often, a poisoner who was put on trial could not be convicted without factual evidence of the poison being in the victim’s body. It was mostly speculation and circumstantial evidence. However, there are now instrumental methods to determine unknown chemicals and substances found at crime scenes.

Gas Chromatography/Mass Spectrometer (GC/MS)

 

The picture above is the GC/MS machine that is located in our school. The Gas Chromatographer is responsible for separating chemical mixtures into pure chemicals while the Mass Spectrometer identifies and analyzes the amount of chemicals. In the GC there are the injection port, oven, and column. In the injection port (#1), the mixture is injected into the GC (#2). Because the inject port is heated to 300 degrees Celsius, the chemicals change into gases. The sample travels through the column (#3) which is located inside the oven. The oven is heated, in turn heating the column, and the sample is carried through it by helium. After traveling through the GC  the sample moves on to the Mass Spectrometer (#4). In the MS there is the ion source, filter, and detector. A picture of the interior of the MS could not be taken because the covering cannot be removed from it. In the ion source, the molecules are bombarded with electrons, thereby breaking the molecules into ions. The ions continue on to the filter where there is a magnetic field that sorts the ions based on mass. The detector counts the number of ions with the specific mass and the data is sent to a computer (#5) that creates a mass spectrum. An interactive diagram of the GC/MS can be found here.

Inductively Coupled Plasma – Mass Spectrometry (ICP- MS)

There are 5 main components in the ICP-MS: sample injection system, inductively coupled plasma (ICP), plasma sampling interface, mass spectrometer, and computer. Like the GC-MS machine explained above, the ICP-MS works in a similar fashion. One of the obvious difference is the use of argon plasma for the ICP-MS ion source.A more detailed explanation of ICP-MS is explained here.

The ICP-MS method is the current standard for testing for arsenic. This is because ICP-MS can detect arsenic in samples as small as 10 mg and also allows for the analysis of multiple elements at a time. The ICP-MS method is capable of analyzing elements with larger molar masses, such as arsenic. Another reason ICP-MS is preferred for the detection of arsenic is because the ions created by the ICP discharge tend to be positive. This is helpful for determining if a sample contains arsenic, because as mentioned previously, arsenic (+5) and arsenic (+3) are the most common forms of arsenic.

These instruments are helpful for identifying the presence of poisons in a substance. In a courtroom, a murderer can now be convicted of poisoning because there is evidence to back up any prior accusations. This could be a possible factor for the decrease in poisonings. Now it is harder to get away with poisoning someone. However, there are still instances where poisoning is overlooked.

“Poison is in everything and nothing is without poison. The dosage makes it either a poison or remedy” (Paracelsus). Would you believe it if I told you that arsenic could actually be used as medicine? Well, believe it or not, arsenic was used by Hippocrates to treat ulcers, and in 1786 arsenic was an ingredient in Fowler’s solution that was used to treat asthma to cancer. Arsenic can be a “poison or remedy” but it is infamous as a poison.

Unlocking the Chemistry of Crime: Serotonin

This video featuring Adrian Raine provides the perfect introduction to the connection between neuroscience and crime.  The exact scene can be found here.

 Crime.

It exists everywhere; in every city, in every country, every day of the year. In movies like Minority Report, the government has  implemented programs to catch murderers before they act. But in the real world, criminals pounce on their prey daily. When one thinks of crime, evil and devious convicts come to mind. But what if crime can be entirely explained through science? Can what urges a single person to perform an act so disastrous, so devious, so illegal, be revealed through science?

Crime & The Human Brain

This image of the human brain displays the different sections different sections.  The red section is the frontal lobe, the green section is the temporal lobe, the yellow is the occipital lobe, the purple section is the insular cortex, the black section is the brain stem, and the blue section is the cerebellum.

In a recent study, brain scans were administered to individuals with an antisocial personality disorder (a common characteristic of many criminals). This disorder typically causes one to “have no regard for right and wrong…[and] violate the law and the rights of others,” according to the Mayo Clinic, a non-profit medical research organization. The brain scans of those with the disorder were compared to a control group without mental disorders. The results concluded that those suffering from the disorder had an 18% reduction in size of their brain’s middle frontal gyrus and a 9% reduction in the size of the orbital frontal gyrus. Both of these sections are important parts of the brain’s frontal lobe.

 

This diagram outlines the different sections of the brain.  The frontal gyrus, which was examined in the study above, is highlighted in orange. Braunstein was a convicted sex offender. One can see the smaller frontal lobe, which is also not as activated in Braunstein as in the normal brain. The frontal lobe controls decision making, problem solving, control of purposeful behaviors, consciousness, and emotions.  The frontal lobe is part of the cerebral system which deals with goal related behavior, distinguishing between “good” and “bad” and resulting impulsive decisions.

Another study examining psychopaths versus a control group demonstrated that psychopaths have a thinner outer layer of the cortex in the amygdala and an 18% smaller size of the brain in that region. Adrian Raine, chair of the Department of Criminology reported that the amygdala is the part of the brain responsible for emotion; thus, psychopaths experience inhibited emotional responses.

Beyond psychopaths, convicted criminals tend to demonstrate behavioral differences compared to the average civilian. Raine explained, “There is a neuroscience basis in part to the cause of crime.” Many of the signs indicating one as a criminal can be found in the brain early on, before an individual develops into their psychopathic or criminal tendencies. A study conducted by Nathalie Fontaine found that those who tended to be callous and unemotional as children had a higher risk of becoming psychopaths in adulthood.

But what is it exactly that makes one predisposed to these criminal tendencies?

What is the difference in the chemical makeup of the brain of a criminal?

How does this all tie back into chemistry?

What is Serotonin?

Neurotransmitters are chemicals in the brain that are responsible for sending signals to different cells throughout the nervous system. Serotonin is one of the most abundant transmitters in the dorsal raphe section, helping to send signals between different parts of the brain. Scientists estimate that serotonin influences most of the brain’s 40 million cells, and due to this function, serotonin has a large impact on one’s psychological functions. In particular, serotonin is known to interact with brain cells that regulate mood, appetite, sleep, memory and learning, body temperature, and some social behavior. When serotonin activity or serotonin levels are disrupted, a person’s psychological state can be altered; this kind of phenomenon is often seen in disorders such as depression and schizophrenia.

This image shows how serotonin is synthesized in the dorsal raphe, and moves throughout the brain, focusing in the frontal cortex.         

Serotonin and Crime

The connection between serotonin and criminal activity is quite clear. Criminals have been found to have a smaller frontal cortex and a smaller amygdala. The central amygdala is part of the section of the brain that releases corticosterone. Corticosterone activates the dorsal raphe, which increases serotonin (5-HT). The direct relationship between the amygdala and serotonin can be hindered when the amygdala is reduced in size, as seen in criminals. Criminals produce less serotonin or have serogentonic dysfunction. An abundance of serotonin can also have negative affects on people causing confusion and induced criminal tendencies. On the other hand, non-criminals have a balanced level of serotonin.

The molecular compound of serotonin (5-HT)

Furthermore, impulsive aggression, a characteristic linked with criminals, is explained through the brain being unable to regulate impulsivity. Dysfunctional interactions occur between the serotonin systems in the prefrontal cortex, which is an important mechanism in controlling aggression. This also links serotonin to certain mental disorders such as depression, suicidal behavior, and drug addiction. Serotonin hypofunction (abnormally low function) demonstrates how one can be predisposed to impulsive aggression, and therefore criminal activity. Lower levels of serotonin (5-HT) have been linked with impulsive aggression (Dongju, Kennealy, & Patrick). One whose genes were programmed to produce less serotonin are therefore more susceptible to criminal activity.

The prefrontal cortex controls behavioral aggression, and impairment of this area would increase impulsive aggression. As seen in criminal brain scans, psychopaths are born with reduced frontal cortexes, increasing their aggression. Serotonin also acts as an inhibiting action in the brain. One of its purposes is to inhibit aggression. However, if serotonergic dysfunction occurs, aggressive behaviour will not be limited, therefore inclining one towards criminal activity. No matter the type of crime, lower levels of serotonin have been linked with aggression, showing how science can be broken down to explain crime. All variations of criminal activity can be simplified down to dysfunctional serotonin. One who is simply born with a defect in their brain, impairing their serotonin production, is predisposed to crime.

The red defined part of this image are the Raphe nuclei (the neurons that make up serotonin). Mentioned in this figure are a few of the behaviors that are affected because of the level of serotonin including mood and aggression.

Connections to Chemistry

Serotonin is produced through a process known as the biochemical conversion process. The process begins when two enzymes, tryptophan hydroxylase (Tph1) and tryptophan hydroxylase-2 (Tph2) help to convert tryptophan to 5-hydroxytryptophan. Decarboxylase enzymes then help convert 5-hydroxytryptophan to serotonin.

Enzymes play a crucial role in the production of serotonin. Therefore, the kinetics behind these enzymes are important to the production of serotonin. Enzymes are responsible for catalyzing, or speeding up, chemical reactions by lowering their activation energies. Specifically, enzymes can lower activation energies by providing a template for reactants to come together, stretching the molecules of a substance, providing a proper microenvironment for a reaction or directly participating in a reaction. Enzymes are ultimately responsible for speeding up the production of serotonin. As a result, a lack of these enzymes could cause dangerously low amounts of serotonin, which could stall the communication between neurons and impact a person’s behavior and psychological state. For example, low levels of serotonin can induce depression, anxiety, post-traumatic stress disorder and attention deficit hyperactivity disorder (ADHD). In the end, serotonin enzymes are a major player in human psychiatric disorders. Thus, a dysfunction with the enzyme can upset serotonin levels, and this chemical process can induce the decision to commit a crime.

 Through the enzyme actions and structure of the brain, one can see the clear connection between serotonin and criminal activity. As mentioned, lower levels of serotonin (5-HT) has been linked with impulsive aggression, and high levels of serotonin have been linked to aggression and confusion. Low levels of serotonin are most prevalent during the winter months, explaining why some people suffer from depression during cold and dark winter months.

Meanwhile, the warmer temperatures in summertime result in higher levels of serotonin. A link can be drawn between serotonin production and thermochemistry. At higher temperatures, the rate of a reaction is increased.  At higher temperatures, the production of serotonin is increased, beyond a “normal” limit in most criminals during the summer months.

James Alan Fox carried out an experiment in Columbus, Ohio, between January 1, 2007 and

December 31, 2007. He displayed the link between crime and temperature. the peak of this graph displays that violent crimes were prominent during the summer months. An increase in temperature results in an increase of serotonin which in turn leads to an increase in crime rates.