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"Biological Extraction" can be a very dangerous undertaking in certain respects.
Take the simplest example. Millennia before the common era, humans already learned to use yeast to produce alcohol and flavor substances from high-starch plants.
But brewing is not entirely safe. Many homemade rural concoctions, though refreshing and not highly alcoholic, result in pounding headaches and a potent aftereffect when consumed.
This is certainly not "drunkenness" in the usual sense. The medical community prefers to call it "congener alcohol poisoning."
During the fermentation of plants, if wild strains other than the yeast in the malt mix into the culture medium and are not rapidly displaced and eradicated by the yeast, the resulting liquor will contain a mixture of congeners, including methanol.
Cases of methanol poisoning leading to blindness due to blind trust in natural airborne microbes were very common in the early 21st century.
