Chapter 19 – Infographic descriptions

19.0a Natural and Man-made Chemicals

Infographic about natural and man-made chemicals. A common misconception is that all man-made chemicals are harmful and all natural chemicals are good for us. However, many natural chemicals are just as harmful to human health, if not more so, than man-made chemicals.

Toxic effects seen at 1000mg/kg of body weight:

Natural:

• Muscimol: found in fly agaric mushrooms
• Solanine: found in green potatoes
• Amygdalin: found in apple seeds

Man-made:

• Ethylene glycol: Used in anti-freeze.
• Aspirin: used as a pain-reliving drug.
• Sodium thiopental: formerly used for lethal injections.

No toxic effects seen at 1000mg/kg of body weight:

Natural:

• Sucrose: also known as table sugar.
• Water: essential for life.
• Citric acid: found in lemons and limes.

Man-made:

• Teflon (PTFE): used in non-stick pans.
• Propylene glycol: food additive-solvent, humectant and thickener.
• Aspartame: artificial sweetener.

“Everything is poison, there is poison in everything. Only the dose makes a thing not a poison.” Paracelsus, 1493-1541, “The father of toxicology”.

Any substance, if given in large enough amounts, can cause death. Some are lethal after only a few nanograms, whilst others require kilograms to achieve a lethal dose.

Chemical toxicology is a sliding scale, not black and white – and whether a chemical is naturally occurring or man-made tells us nothing about its toxicity.

Read more about “Natural vs. Man-Made Chemicals – Dispelling Misconceptions [New tab]” by Andy Brunning / Compound Interest, CC BY-NC-ND

19.0b The chemical compounds behind the smell of flowers

Infographic on aroma compounds in common flowers. A wide range of compounds contribute to the scent of flowers. The following is a majority of the common flowers and a broad overview of their components, with chemical structure images. Note that the volatile aroma compounds can vary significantly between species.

• Roses: (-)-cis-rose oxide, beta-damascenone, beta-ionone.
• Carnations: eugenol, beta-carayophyllene, methyl salicylate.
• Violets: alpha-ionone, beta-ionone, beta-dihyroionone.
• Lilies: linalool, (E)-beta-ocimene, myrcene.
• Hyacinth: ocimenol, cinnamyl alcohol, ethyl 2-methoxybenzoate.
• Chrysanthemums: alpha-pinene, eucalyptol, chrysanthenone.
• Lilacs: (E)-beta-ocimene, lilac aldehyde, lilac alcohol.

Read more about “The Chemical Compounds Behind the Smell of Flowers [New tab]” by Andy Brunning / Compound Interest, CC BY-NC-ND.

19.5a A brief guide to doping in sports

Doping in sports has been in the news in the run up to the Olympics. What drugs will doping tests at the Olympics be looking for? See below some of the major groups of drugs used in doping, their effects, and why athletes might take them.

Anabolic agents:  The largest class of prohibited drugs, and the most commonly detected. Anabolic steroids mimic the hormone testosterone, increasing muscle mass and physical strength. This class also includes some non-steroidal drugs. They have a range of side effects. 74 named banned agents. 48% of positive tests in 2014.

Stimulants: Stimulants are used to improve alertness, attention and energy. Many behave similarly to the hormones adrenaline and noradrenaline. They include amphetamines. Taking them can increase blood pressure and cause cardiac problems. 66 named banned agents. 15% of positive tests in 2014.

Hormones and modulators: A range of drugs which generally interfere with human hormones, including meldonium. They can be used with anabolic steroids, to suppress some of the undesirable effects of these drugs. Some affect oestrogen levels in the body, whereas others affect human metabolism. 20 named banned agents. 5% of positive tests in 2014.

Diuretics and masking agents: This includes furosemide. Diuretics remove fluids from the body and can be used by athletes to regular their body mass, as well as diluting urine so lower levels of banned substances are registered in tests. Masking agents are drugs taken to conceal the presence of illegal drugs in urine samples. 22 named banned agents. 13% positive tests in 2014.

Read more about “A Brief Guide to Doping in Sports [New tab]” by Andy Brunning / Compound Interest, CC BY-NC-ND

19.6a Organic Chemistry Reaction Map

Read more about “Organic Chemistry Reaction Map [New tab]” by Andy Brunning / Compound Interest, CC BY-NC-ND

19.6b A Short Guide to Arrows in Chemistry

Infographic on a short guide to arrows in chemistry.

Chemical reaction arrows:

• Reaction arrow: These arrows point from the reactants to the products of a chemical reaction. Reaction conditions, reagents or catalysts may be written above or below the reaction arrow.
• Multiple arrow: Chemists use stacked multiple arrows to indicate that there are several reaction steps between the reagents and the products shown on either side of the arrows.
• Broken arrow (an arrow with an ‘x’ through it or an arrow with slanting parallel lines): Chemists use these arrows to indicate chemical reactions that do not take place. The reactants shown cannot be transformed into the products shown.
• Reversible reaction arrow (two arrows running parallel pointing opposite directions): Chemists use these arrows to indicate that a reaction is reversible – the reactants react to produce the products, but the products can also react to make the reactants.
• Equilibrium arrow ( two parallel half-headed arrows pointing opposite directs): These arrows show that a reversible reaction is at equilibrium: the forward and reverse reactions occur at the same rate. The length of the arrows can be varied to show if reactants or products are favoured.
• Retrosynthesis arrow (two parallel lines with an arrow head pointing in one direction): Organic chemists us these arrows to show that the molecule on the left can be made from the stating material on the right, often through several reaction steps.

Electron movement arrows:

• Resonance arrow (one double headed arrow pointing opposite directions):  Chemists use these arrows to show different resonance forms of the same molecule. The forms differ in electron arrangements; the true structure of the molecule is an average.
• Curly arrow (an arched arrow or half headed arched arrow): Curly arrows show electron movement in reaction mechanisms in organic chemistry. A double headed arrow shows the movement of an electron pair, while a single headed arrow shows the movement of a single electron.

Read more about “A short guide to different arrows in chemistry [New tab]” by Andy Brunning / Compound Interest, CC BY-NC-ND

19.7a The Twelve Principles of Green Chemistry: What it is, & Why it Matters

Green chemistry is an approach to chemistry that aims to maximize efficiency and minimize hazardous effects on human health and the environment.  While no reaction can be perfectly “green”, the overall negative impact of chemistry research and the chemical industry can be reduced by implementing the 12 Principles of Green Chemistry whenever possible.

1. Waste prevention: Prioritize the prevention of waste, rather than cleaning up and treating waste after it has been created.  Plan ahead to minimize waste at every step.
2. Atom economy: Reduce waste at the molecular level by maximizing the number of atoms from all reagents that are incorporated into the final product.  Use atom economy to evaluate reaction efficiency.
3. Less hazardous chemical synthesis: Design chemical reactions and synthetic routes to be as safe as possible. Consider the hazards of all substances handled during the reaction, including waste.
4. Designing safer chemicals: Minimize toxicity directly by molecular design. Predict and evaluate aspects such as physical properties, toxicity, and environmental fate throughout the design process.
5. Safer solvents and auxiliaries: Choose the safest solvent available for any given step. Minimize the total amount of solvents and auxiliary substances used, as these make up a large percentage of the total waste created.
6. Design for energy efficiency: Choose the least energy-intensive chemical route.  Avoid heating and cooling, as well as pressurized and vacuum conditions (i.e. ambient temperature and pressure are optimal).
7. Use of renewable feedstocks: Use chemicals which are made from renewable (i.e. plant-based) sources, rather than other, equivalent chemicals originating from petrochemical sources.
8. Reduce derivatives: Minimize the use of temporary derivatives such as protecting groups. Avoid derivatives to reduce reaction steps, resources required, and waste created.
9. Catalysis: Use catalytic instead of stoichiometric reagents in reactions. Choose catalysts to help increase selectivity, minimize waste, and reduce reaction times and energy demands.
10. Design for degradation: Design chemicals that degrade and can be discarded easily. Ensure that both chemicals and their degradation products are not toxic, bioaccumulative, or environmentally persistent.
11. Real-time pollution prevention: Monitor chemical reactions in real-time as they occur to prevent the formation and release of any potentially hazardous and polluting substances.
12. Safer chemistry for accident prevention: Choose and develop chemical procedures that are safer and inherently minimize the risk of accidents.  Know the possible risks and assess them beforehand.

Read more about The Twelve Principles of Green Chemistry: What it is, & Why it Matters [New tab] by Andy Brunning on Compound Interest, CC BY-NC-ND 4.0.

 19.7b Dandelion chemistry: Diuretics and the tyres of the future

Dandelions’ Medicinal Uses

The Frech name for dandelion is pissenlit (‘wet the bed’) from their supposed ability to act as a diuretic, increasing the production of urine. Research attributes this to several diuretic compounds, but evidence for the effect is mixed. Dandelions’ high potassium content helps replace potassium lost through urine.

Potassium content of dandelion leaves versus bananas: Dandelion leaves 397 mg per 100 g.  Bananas 358 mg per 100 g. (Source: US Department of Agriculture – FoodData Central)

Studies show dandelion extracts or compounds have anti-inflammatory, anti-carcinogenic and anti-oxidative actions. These effects are mostly due to polyphenols and sesquiterpenese, also responsible for the bitter flavour of the leaves.

Taraxinic acid β-D-glucopyranoside – A sesquiterpene lactone in dandelion, also thought to be a contact allergen.

Rubber from Dandelions

The sticky white liquid that seeps out from dandelion stems when they’re picked contains a natural latex, which can be turned into rubber. The roots of Russian dandelions (Taraxacum koksaghzy) contain a particularly high percentage of latex, making them ideal for rubber production.

Percentage of the USSR’s rubber provided by the Russian dandelion during rubber shortages in World War II. 1941: 30%

Main constituent of rubber: cis-1,4-polyisoprene

In the past decade, tyre manufacturers have been developing dandelion rubber tyres. Currently bike tyres made from dandelion rubber are commercially available and tyres for cars and trucks will be available within ten years.

Read more about Dandelion chemistry: Diuretics and the tyres of the future [New tab] by Andy Brunning on Compound Interest, CC BY-NC-ND 4.0.

Attribution & References

Compound Interest infographics are created by Andy Brunning and licensed under CC BY-NC-ND

Except where otherwise noted, content on this page has been created as a textual summary of the infographics used within our OER. Please refer to the original website (noted below each description) for further details about the image.