The Chemistry of Snow

The Golden Age of Hollywood’s Silent Film industry was fuel by a mix of gin and cocaine. The Chemistry of Snow, as cocaine is called because…

Reader: …

Vanessa: What?

Reader: It’s the Holidays…

Vanessa: Crime happens during holidays too.

Reader: …

Vanessa: You want to talk about the Other type of snow. *sigh* Fine.

The Chemistry of Snow (Part I—Natural)

Catching delicate snowflakes on your tongue is a highlight of a winter walk. Of course, the chemistry of snow is simple H₂O and cold. This simplicity belies the complexity of the snowflake. How cold does it need to be to form the perfect snow flake?

Formation of Snowflakes

A particle in the atmosphere, it could be a mineral or an organic substance, collects water around it.  Because of the nature of the hydrogen bonds, (image 1) the snowflake will be hexagonal, the little six-pointed star of Christmas Decorations (Brunning, 2020).

Image 1: A snowflake condenses around a particle.
Credit V. Knipe

The nature of the particle is important, in areas of high pollution, snow will form around, and concentrate, the pollution. When the snow melts, it releases the toxins into the water supply, and into the food chain (Bartels-Rausch, 2013).

So they really are little Six Pointed Stars?

The actually shape of snowflakes depends on the temperature at which they form. The little star-like plates appear between -2°C and -5°C. From -5°C to -15°C snow becomes hexagonal columns, at which point it shifts back to plate formation(Howgego, 2021).

Did you really think I wasn’t going to mention forensics?

Footprints in snowy conditions can be really helpful to the police, but how  are they captured for examination? In a previous article I covered this in more detail. The main problem with casting footprints in snow is that Dental Stone, the form of plaster commonly used to take casts of footwear marks, gives off heat as it dries. Which melts the snow. A fixer of some sort must be used. The least expensive way of casting an impression involves a spray of snow print wax, at least three layers, helps preserve the print as the dental stone dries. There are other more expensive options such as Sulfur Cement or plain yellow sulfur in paste form. Both of these are health and safety hazards, as they give off toxic fumes (Forensic Reader, 2022).

The Chemistry of Snow (Part II—Artificial)

Not everywhere gets snow, and places where it snow is requires, such as ski slopes, sometimes get bad years. How about the Christmas Movies that are filmed in the summer for release in December, what to do then? Movies use any number of products to fake snow, including paper, plastic and polystyrene (Burke, 2011).

Kitchen Chemistry

One of the easiest way to make artificial snow is similar to the children’s volcano mix of bicarbonate and vinegar. The snow mixture includes dishwashing soap. The soap traps the effervescing CO₂ gas. This product can be blown around and act like falling snow, but it will not settle. It bursts the moment it touches a surface (Science Buddies, 2015).

Ski slope Chemistry

If you are looking to improve the chances of your skiing holiday, then a resort with a snow-making machine is a must (image 2).

Image 2: A Snow Making Machine.
Credit: https://commons.wikimedia.org/wiki/File:Schneekanone.JPG

The first snow-making machines required cold weather. They sprayed water or mist into the air, which then fell as snow. To increase efficiency, the machines mixed in a small particulate to help the formation of the flakes. The best particulates are plant-based and biodegradable, to prevent the hazards of pollution (Burke, 2011).

However, if the weather is too warm then you might  want the modern version of snow on the ground, the polymer sodium acrylate, (C₃H₃NaO₂)_n. When wet, the previously coiled, powdery molecules, form a negative charge and repulse each other (Brunning, 2017). The product of this reaction looks like real snow and is non-toxic (University College London).

The Chemistry of Snow (Part III—Original Topic)

The Golden Age of Hollywood’s Silent Film industry was fuel by a mix of gin and cocaine. The latest movie on the subject, Babylon, (review here) uses this as its premise (Newland, 2022). Fatty Arbuckle was a known user and addict of cocaine (Kemp, 2022). However, when mixed with alcohol, the likelihood of sudden death is increased (Healthwise, 2022).

Brief History of Cocaine

To understand cocaine it is best to study the history of the drug. Coca leaves have been chewed and brewed into tea, by native South Americans for generations, to produce a feeling of euphoria. Priests used it in their rituals and it helps to overcome the effects of altitude sickness (Blickman,2014). The German Chemist, Albert Niemann, extracted cocaine from coca leaves in 1859. Sigmund Freud chose the compound to cure depression and impotence (Kemp, 2022). The public of the time considered cocaine to be the latest ‘superfood’ fad; many patent medicines and tonics included cocaine as an active ingredient (Blickman, 2014). And of course, it’s common knowledge that Coca-Cola once contained cocaine, but that is an exaggeration. It contained extract of coca leaves, not the purified cocaine discovered by Niemann (Snopes Staff, 1999), creating a less potent form of the tea the South American priests used to brew. In 1914 the Harrison Act made cocaine illegal in the United States (Hutchinson, 2022). The Dangerous Drugs Act of 1920 made it illegal in the UK.

The Chemistry of Leaves to Snow

Cocaine is a semi-synthetic drug, based on a natural substance that requires effort to create the finished product. A long and tedious process turns the leaves into cocaine. The leaves are soaked for days in a mix of alkali and water, then the precursor to cocaine is extracted into kerosene. It is extracted again with an acid and eventually is packaged for transport as coca paste.  This requires further processing at the destination to produce the final product (The Forensic Library).

The Chemistry of Artificial Snow

So how do coca plants produce cocaine? This has troubled science for a long time. Most of the biochemical reaction in the leaves was mapped out, but there was a broken thread in the reaction chain. The leaf conversion from MPOA (image 3  to cocaine was a mystery.

Image 3: Production of Cocaine in Leaves
Credit: Yong-Jiang, 2022

Chemists learned how to synthesise cocaine, starting with methyl ecgonine hydrochloride, but that is not how leaves perform the reaction. More recently a Genetics company modified tobacco plants to produce cocaine, and in doing so they identified two enzymes (marked in red on image 3) that produce the conversion (Wilkins, 2022). However, the tobacco plants cannot produce enough cocaine for medical purposes.

Medical Uses of  Cocaine

The first real medical use for cocaine was as an anaesthetic. Carl Koller, an ophthalmologist from Vienna, used it in eye operations in 1884 (Georig, 2012). In the hydrochloride form, cocaine is still used as a local anaesthetic in the US. The compound is a vasoconstrictor, as such it reduces swelling and bleeding during surgery (Sugar, 2022).

Detection of Illegal Use

Regrettably, cocaine is used as an illegal high. As mentioned in a previous article, the ‘gold standard’ of drug detection is mass spectrometry. But carrying a Mass Spec in the field is impossible. There are a number of field kits that perform a colorimetric change in the presence of drugs based on the Scott’s Test, an officer uses images on a smart phone to determine a positive or negative result. These are only presumptive tests, they must be confirmed by Mass Spectrometry or other tests such as Fourier Transform Infrared Spectroscopy or High Performance Liquid Chromatography (The Forensic Library) in order to stand up in court.

On the other hand, if a police officer has reason to suspect drug use, the basic test for cocaine in humans is a urine drug screen. First a dipstick presumptive test is performed and then confirmatory Mass Spectrometry (Harper, 2017).

Street Drugs

The snow purchased on the street is rarely a pure product. Dealers often cut the pure drug with adulterants which look similar to cocaine, such as sugar or talcum powder. In other instances another drug will be present: a local anaesthetic or an amphetamine (Healthwise Staff, 2022) which produces an effect in the user.

Finally

Despite the jolly time of year, crime continues to happen. So while some people believe that snow is something that falls from the sky in winter, others will be looking for a quick high on snow, or cocaine.

References

Bartels-Rausch, T. Ten things we need to know about ice and snow. Nature 494, 27–29 (2013). https://doi.org/10.1038/494027a

Blickman, T. (2014) Coca Leaf: Myths and Reality. TNI. August 5. https://www.tni.org/en/primer/coca-leaf-myths-and-reality

Burke, M. (2011) Let it Snow. C&I. Issue 24. https://www.soci.org/chemistry-and-industry/cni-data/2011/24/let-it-snow

Brunning, A. (2020) Period Graphics: The Chemistry of Snow and Ice. C&EN. January 26. https://cen.acs.org/articles/98/i4/Periodic-Graphics-chemistry-snow-ice.html

Brunning, A. (2017) 7 December—Fake Snow Chemistry. Compound Interest. https://www.compoundchem.com/2017advent/2017advent7/

Dangerous Drugs Act 1920: Criminalising Opium and Cocaine possession. https://navigator.health.org.uk/theme/dangerous-drugs-act-1920-criminalising-opium-and-cocaine-possession

Forensic Reader. (2022) How To Cast Footprints on Snow? Forensic Impression Materials. ForensicReader.com https://forensicreader.com/how-to-cast-footprints-on-snow/

Goerig, M., Bacon, D., & van Zundert, A. (2012). Carl Koller, cocaine, and local anesthesia: some less known and forgotten facts. Regional anesthesia and pain medicine, 37(3), 318–324. https://doi.org/10.1097/AAP.0b013e31825051f3

Harper, L., Powell, J., and Pilj, E.M. (2017) An overview of forensic drug testing methods and their suitability for harm reduction point-of-care services. Harm Reduction Journal. 14:52 DOI 10.1186/s12954-017-0179-5

Healthwise Staff. (2022) Cocaine. Healthwise. August 2. https://www.cham.org/HealthwiseArticle.aspx?id=uq2452

Howgego, J. (2021) Kenneth Libbrecht interview: A grand unified theory of snowflakes. New Scientist. December 15. https://www.newscientist.com/article/mg25233653-800-kenneth-libbrecht-interview-a-grand-unified-theory-of-snowflakes/

Hutchinson, S. (2022) Cocaine’s History in America: Was it Ever Legal? River Oaks Treatment Center. November 1. https://riveroakstreatment.com/cocaine-treatment/illegal-history-in-america/

Kemp, S. (2022) How Cocaine Became the Hollywood Drug of Choice. Far Out Magazine. May 9. https://faroutmagazine.co.uk/cocaine-hollywoods-drug-of-choice/

Newland, C. (2022) Babylon: The Truth Behind the Outrageous Hollywood Epic. BBC Culture. https://www.bbc.com/culture/article/20221213-babylon-the-truth-about-the-scandals-of-the-silent-film-era

Science Buddies. (2015) Foamy White “Snow”. Scientific American. December 31. https://www.scientificamerican.com/article/foamy-white-snow/

Snopes Staff. (1999) Did Coca Cola ever Contain Cocaine? Snopes. May 19. https://www.snopes.com/fact-check/cocaine-coca-cola/

Sugar, D. ed. (2022) Is Cocaine Approved for Legal Use? ARK Behavioral Health. July 4. https://www.arkbh.com/illicit-drugs/cocaine/medical-use/

The Forensic Library. Cocaine. Forensic News. https://aboutforensics.co.uk/cocaine/

University College London. Artificial Snow. Institute of Making. https://www.instituteofmaking.org.uk/materials-library/material/artificial-snow#:~:text=Artificial%20snow%20is%20made%20of,its%20own%20weight%20in%20water

Wilkins, A. (2022) Genetically Modified Tobacco Plant make Cocaine in its Leaves. New Scientist. Dec 3. Page 20.

Yong-Jiang Wang, Jian-Ping Huang, Tian Tian, Yijun Yan, Yin Chen, Jing Yang, Jianghua Chen, Yu-Cheng Gu, and Sheng-Xiong Huang. Journal of the American Chemical Society 2022 144 (48), 22000-22007 DOI: 10.1021/jacs.2c09091