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THE LAST WORD
Worm wouldn’t? Absinthe was supposed to have hallucinogenic effects due to the presence of extracts of the wormwood plant and has been banned in some countries at various times. Does this effect really exist?
n The hallucinogenic properties of absinthe are generally ascribed to thujone, extracted from wormwood. Thujone is bitter with a slightly minty, aniseed-like taste and found in plants such as sage, oregano and juniper. However, because of absinthe’s strength – sometimes more than 80 per cent alcohol by volume – and poor production techniques, the drink traditionally contained high levels of methanol. It is more likely that hallucinations, spasms and seizures attributed to thujone were caused by the methanol content, and that this led to bans on absinthe’s sale, import and export.
Modern distilling techniques result in spirits with negligible methanol, if any. In the European Union, absinthe is usually between 45 and 75 per cent alcohol by volume and has a maximum legal thujone content of 35 milligrams per litre. As a rule of thumb, the higher the alcohol content and darker the colour, the better the quality.Dylan BrewisLondon, UK
n The history of absinthe is so fraught with urban legend and conflicting interests that no categorical answer to the question
can be trusted. Even in the 19th century, the relative importance of the alcohol and the essential oils of wormwood (mainly Artemisia absinthium ) in absinthe was much disputed.
Certainly thujone, the main active ingredient, is neurotoxic and can produce many of the symptoms of concern, and it is plausible that long-term heavy use might produce some of the alleged chronic effects. However, the likelihood of more modest drinking habits being harmful is bitterly disputed. Some people still blame van Gogh’s mental decline on his consumption of absinthe, arguing that in those days the concentration of thujone was
dangerously high, justifying its banning in some countries. Others assert that absinthe has hardly changed and is a benign intoxicant, stimulant, or both. Jon RichfieldSomerset West, South Africa
n Absinthe is not hallucinogenic. I am drinking a glass of it as I write.
Absinthe contains the compound thujone which was once considered, on account of its molecular shape, to be part of a class of compounds called cannabinoids, which suppress neurotransmitters in the brain.
But, in 1999, J. C. Meschler and A. C. Howlett showed this to be false (Pharmacology Biochemistry and Behavior, DOI: 10.1016/S0091-3057(98)00195-6).
Absinthe’s reputation was generated by French winegrowers. Around the beginning of the 20th century, the French were drinking 36 million litres of absinthe annually and this was hitting the winegrowers’ pockets.
The growers fought back with the aid of a burgeoning temperance movement, which bizarrely regarded wine as “natural” because it came from the land. The winegrowers claimed that absinthe caused hallucinations, epileptic fits and suicides. They produced lurid posters and even created a medical-sounding term: “absinthism”. A number of cut-price absinthe producers inadvertently aided them by using low-grade alcohol and a variety of genuinely toxic substances.
The anti-absinthe hysteria reached its climax when a vineyard worker in Switzerland, Jean Lanfray, shot his pregnant wife and two daughters before attempting, unsuccessfully, to kill himself. Public reaction focused on one detail: the two glasses of absinthe he had consumed.
The fact that Lanfray was an alcoholic was ignored. On the day of the attack he had not only drunk the two glasses of absinthe, but also downed a crème de menthe, six cognacs, seven glasses of wine with his lunch, another glass of wine before
leaving work, a cup of coffee with brandy in it, an entire litre of wine after getting home and then another coffee with brandy. But such was the hysteria that people were in no doubt; absinthe was the cause. By 1908, the first ban became definitive.
Fortunately saner views prevailed and, in 2005, absinthe was re-legalised in its country of origin, Switzerland. Santé!Alistair ScottGland, Switzerland
This week’s questionsBack To fronT?Sitting up straight using back and core muscles instead of slouching is better for posture and less likely to contribute to back problems. Why, then, is slouching more comfortable? How does it make sense biologically that the worse option is the easier?Nick BrownOxford, UK
BreaThing SpaceOur 43-year-old house has ventilation bricks in the external walls and vents in the plasterboard lining of the rooms. Are the vents there to air both the wall space and the living space? It has been suggested that we block the internal vents to reduce the electricity we use for heating. Is this safe, and have views on home ventilation changed since our house was built? Jennifer AtkinsonHobart, Tasmania, Australia
“Thujone from the wormwood in absinthe is neurotoxic and can cause symptoms of concern”
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