Tobacco Nicotine Death of the Bee

Tobacco is another commonly abused stimulant. It contains nicotine as the major stimulant. As mentioned earlier (Sect. 17.1), our brain has a receptor for nicotine, a part of acetylcholine receptor. Nicotine is an alkaloid and its structure is shown in Fig. 17.2. Tobacco plants produce nicotine as a defense chemical, to kill some insects. Nicotine has indeed been used as an insecticide for long. It is poisonous to human body, too, and a small amount can kill. In smaller quantities (as found in inhaled smoke), it can act as a stimulant interacting with the receptor as mentioned earlier, and it is quite addictive. 

Chemical compounds that have some characters similar to nicotine have been synthesized in recent decades and have widely been used as insecticides. They are collectively called neo-nicotinoid . One of them, called clothianidin, has recently been shown to be a major cause of colony collapse disorder (massive sudden death of bees). It is believed to bind to the brain of bees (and other insects) as nicotine does, and disrupts their brain function. It has been reported that the colony collapse has dramatically decreased once neo-nicotinoid was banned in Germany. 

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