Never Mind the Bullocks, Here's the Science (4 page)

Absinthe had a following among the Bohemian artists of Paris. The famous 1875-76 Degas painting
Dans un Café
has the subtitle
L’Absinthe.
Apparently it was ‘hissed at’ when it was auctioned in the early 1890s, due to its ‘depraved’ subject matter. Manet painted
The Absinthe Drinker
, while in 1887 Henri de Toulouse-Lautrec did a pastel drawing of Vincent van Gogh with a glass of absinthe, while van Gogh himself painted a still life of a carafe and a glass of absinthe. On 27 July 1890, van Gogh shot himself. A thuja tree (a source of wormwood oil) was planted on his grave, probably inspired by van Gogh’s love of thuja trees, whose flame-like images he included in some of his paintings.

However, as imbibing absinthe became all the rage with Parisians, ‘absinthism’ also became recognised as a medical illness.

A key ingredient of absinthe is WORMWOOD, a small shrub belonging to the daisy family.

Absinthism

In 1879, a Dr Richardson wrote in
The New York Times
a fairly typical description of ‘absinthism’: ‘The bitterness increases the craving or desire, and the confirmed habitué is soon unable to take food until he is duly primed for it by the deadly provocative. The sufferer…is left cold, tremulous, unsteady of movement, and nauseated…In the worst cases, the person becomes a confirmed epileptic.’

An 1882 report from
The New York Times
noted: ‘The poor wretches given up to absinthe-drinking suffer from a peculiar train of nervous symptoms, the most prominent of which is epilepsy of a remarkably severe character, terminating in softening of the brain and death.’ The report then discusses a man known to drink large quantities of absinthe. ‘The convulsions lasted until death—four days and four nights. During the last five or six hours of life the skin of the face became almost black.’

And, of course, lurid prose was written to deter still-innocent potential imbibers from even thinking of drinking absinthe.

A typical example from
The New York Times
of 1884 had the enticing title of ‘The charms of absinthe: The allurements it holds out to its victims, and the sting that comes afterwards, confessions of a Frenchman who succumbed to it’. In a bar, a disgustingly healthy and fresh-faced American youth sees a ‘tall, sallow-faced Frenchman, with a heavy and carefully waxed moustache’ drinking a glass of absinthe. The Frenchman tells the sorry tale of his downfall, from being a brilliant, wealthy and well-connected medical student with a glowing future, to the unwell absinthe-addicted loner who had lost his friends and his future. He confesses, ‘…I lost my power of reasoning. I had no more idea of a correct syllogism than I had of the man in the moon. This was followed by utter prostration. It ended in delirium tremens. I just
escaped a lunatic asylum.’ In response to this precautionary tale, the shaken young American vows to abstain from the awful absinthe.

And It Gets Worse…

Despite this bad press, the consumption of absinthe increased even further in the 1880s and 1890s, especially in France.

This was due to two factors. First, an imported American bug, the aphid, had attacked French grapevines, destroying many French vineyards, and so the production of wine dropped precipitously. Second, there was a huge increase in the mass production of absinthe, significantly dropping its price. As a result, the annual consumption of absinthe in France increased by 15 times from 1875 to 1913, to some 40 million litres.

Death of French Vineyards

In the 16th century, French colonists brought European grapevines to Florida in the USA to grow grapes. They failed.

A tiny North American insect (the ‘yellow aphid’ or ‘plant louse’) attacked the roots of the European grapevines. It stabbed the roots with its snout or proboscis. It would inject toxic saliva through one ‘pipe’ in the proboscis and suck up the sap to feed itself through another pipe. As the plant got sick, its internal pressure reduced, making the sap too hard for the aphid to extract, so it moved to another plant. When the colonists pulled up the dead plants to examine the roots, there were no aphids – so they never realised that the aphids were the cause.

The aphids behaved quite differently on North American vines. In these native plants, they attacked the leaves, making little ‘galls’ on the plants – structures
that were their homes, as well as nurseries to the millions of tiny baby aphids. In eight months, a single female could produce some 25 billion descendants.

Around 1860, the aphids travelled on the roots of some North American vines to Europe. They survived the trip because the new steamships were a lot faster than sailing ships. The disease first surfaced in 1863. It took three years to act. In the first year the leaves died; in the second year the grapes died and dropped off; and in the third year the vine itself died. In the otherwise very good vintage year of 1865, vines began dying in the communes of Gard and Vaucluse, for no apparent reason. In 1868, the botanist Professor Jules-Emile Planchon dug up and examined the roots of a variety of vines – i.e. healthy, dying and dead ones. He noticed the tiny yellow aphids on the healthy and dying plants, but not on the dead ones. He called this particular aphid
Phylloxera
(Greek for ‘dry leaves’)
vastrix
(Latin for ‘devastator’).

In 1870, France and Prussia went to war. France took six years to recover from this war, but it took a generation to restore the damage done to the vineyards by the aphids. In fact, aphids cost France five billion francs – twice the amount that France had to pay as reparations for its defeat by Prussia in the Franco-Prussian war.

The cure was related to the cause. The aphids did not attack North American grapevine roots. But the French did not like the taste of North American grapes. So vast quantities of North American grapevine roots were imported into Europe, and the local vines were grafted onto these resistant roots. The grapes from the grafted local vines were thought to have virtually the same flavour as before, and to be unaffected by growing on top of an American vine root. Even so, the Burgundy vineyards wanted to protect their reputation, and banned any North American varieties until 1887.

However, the writing was on the wall for absinthe. Thanks to absinthism becoming a major and increasing social problem, absinthe was banned in Switzerland in 1908. In the USA, it was regarded with such horror that it was banned in 1912—two years before heroin and cocaine were banned. And it was even banned in its natural home of France in 1915.

At the time, absinthism was blamed on a specific chemical called thujone. This thujone was found in the wormwood herb used to make absinthe.

But now, in the 21st century, absinthe is legally available in most of the Western world, provided that the thujone level in the bottle is less than 35 ppm (parts per million).

Thujone—Part 1

So, can thujone cause fits? Yep, it is true that thujone in concentrated amounts can cause convulsions, as well as other medical problems.

In one case, a 31-year-old man bought some little bottles of ‘essential oil of wormwood’ via the internet. The supplier sold it as an aromatherapy oil—something to be smelled,
not
drunk. But the buyer drank a 10 ml bottle of the oil. Shortly afterwards, his father found him having convulsions, and he became disoriented, lethargic, belligerent, agitated and incoherent. The concentrated wormwood oil had also begun to destroy his muscles—the breakdown products of which had entered his bloodstream and clogged up his kidneys, causing temporary kidney failure. He also had congestive heart failure. Thanks to rapid medical treatment, he recovered and was discharged from hospital after nine days.

One of the toxins in wormwood oil has been identified as alpha-thujone. Normally the human brain runs in a delicate balance, poised between too much and too little activity. Natural chemicals present in the human brain regulate it by slowing it down and speeding it up. One of the ‘slow down’ chemicals is GABA (gamma-aminobutyric acid). Alpha-thujone blocks the natural inhibitory action of GABA, leaving the nerves able to fire off too easily.

Therefore, the ingestion of too much wormwood oil will definitely cause convulsions.

Wormwood and Thujone

The name ‘wormwood’ comes from the belief that this plant would fight worms living in your gut. Way back in the first century BC, Pliny the Elder wrote in his
Historia Naturalis
that wormwood had this action. Even way back then, he noted that the use of wormwood as a medicine was an ancient practice.

Wormwood is also mentioned in the
Book of Revelations
8:10-11: ‘A great star from heaven, burning as if it were a lamp, and it fell upon the third part of the rivers, and upon the foundations of waters; and the name of the star is called Wormwood: and the third part of the waters became wormwood; and many men died of the waters, because they were made bitter.’

Wormwood is first mentioned in the Ebers Papyrus, dating back to between 3550 and 1550 BC. It is also mentioned in three of Shakespeare’s plays.

The active ingredient in wormwood is a chemical called thujone (C
₁₀
H
₁₆
O). It is found, in varying levels, in most species of
Artemisia
, a genus of the daisy family. Thujone is also found in other plants such as tansy, sage and white cedar.

However, the main sources of this chemical are regular wormwood (
Artemisia absinthium
) and Roman wormwood (
Artemisia pontica
). The plant is a herb with a perennial root system, with firm, leafy branched stems that reach to a height of 0.6-1 m. Wormwood has tiny globular yellow-green flowers and silver-grey leaves. Oil of wormwood (containing thujone) is extracted from all parts of the plant.

Essential Oil

If you go to a weekend market and follow your nose, you may end up at a stall selling a variety of essential oils.

These oils are originally stored as microdroplets in the glands of plants. They diffuse through the walls of the glands to spread over the surface of the plant and evaporate, filling the surrounding air with a perfume.

In most cases, we do not know the function of these essential oils in the plants.

But we use them as deodorisers, for adding flavour and, in some cases, as pharmaceuticals.

Thujone—Part 2

So, did thujone cause absinthism?

Almost certainly not, according to Dr Dirk W. Lachenmeier from the Chemical and Veterinary Medicine Investigation Laboratory in Karlsruhe in Germany.

First, some varieties of wormwood (e.g. those from the Spanish Pyrenees) that are used to make absinthe have zero levels of thujone.

Second, the levels of thujone found in the tested bottles of absinthe were much too low to cause absinthism. Dr Lachenmeier tested 13 bottles of pre-ban absinthe and found their average level of thujone to be 25 ppm, with the highest only 48 ppm. To get the absinthism effect from the thujone, you would have to drink so many litres of absinthe that its alcohol content would kill you first.

Furthermore, we still have some of the recipes that were used to make absinthe in the old days. Typically, low amounts of dried
wormwood were added, which would give the low levels of thujone measured by Dr Lachenmeier.

No,
alcohol
caused absinthism—in other words, absinthism was plain old alcoholic poisoning. While whisky and other spirits rate at 40-50% alcohol by volume, absinthe was typically 70%, and has been measured at 90% alcohol. The alcohol level needs to be so high to ensure that the essential oils are dissolved. This keeps the liquid clear, not murky. When ice-cold water (part of the ritual) is added to the absinthe, some of the oils come out of the solution and make the drink cloudy. This milky opalescence is given the exotic-sounding name of
louche.

The demon alcohol by itself can account for all the symptoms of absinthism. In his article ‘Thujone—cause of absinthism?’, Dr Lachenmeier wrote: ‘Thujone plays none, or only a secondary role, in the clinical picture of absinthism.’ And, of course, some of the adulterants of the day—e.g. copper salts and antimony trichloride, which were used to enhance absinthe’s colour, clarity and flavour—were themselves poisonous.

In the early 20th century, absinthe also became a scapegoat. It was often blamed for deaths caused by ‘embarrassing’ conditions—such as sexually transmitted infections like syphilis—to protect the good name of the family of the deceased.

So perhaps the worm has turned to wipe the slate clean on wormwood—and to dispel the cloudy reputation of absinthe as well.