This is the phenomenon of "releasing". When one consumes cannabis, THC enters the blood circulation and provokes effects that are later sought by the user. THC is stored in the body fats from where it is released in case of stress or fear. Many road accidents can be explained this way.
When in a dangerous incident on the road, the situation awareness of a consumer, whose reflexes are already impaired even if he has not used recently, is modified. He may be able to avoid the accident, but he is scared. The THC stored in the body fats is then released. It is more than likely that at the next intersection, without any obvious reason, an accident will occur.
One can never know the amount that is stored in the fats. It depends on one's body, on the product that has been consumed and on the releasing that has been occurring.
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