The reason for not to eat basal leaf by biting

We have heard that the basal leaves are good for eating. But some people are telling we should not eat leaves by biting. Do you know the reason? I will explain.The basal leaves are used for worship and also in medicine. We can use the flower,fruit,leaf,wood and root of the basal plant. The leaf is used to treat common cold and the root is used for treating fever. We can use the dried basal plant by grinding for intestinal problems. The boiled basal water is good for patients to drinking. The ear pain,hearing problem and pus from ear can be treated by pouring 3 or 4 drops of basal essence to it. Regarding basal some myth also is there. So the way of plucking the leaf also is different. Scientifically this leaf is having mercury which is not good for the teeth. That’s why we should not eat it by biting. We should not pluck the leaf at night because it will produce carbon dioxide with the lack of photosynthesis. If we go near to the plant that time will be unhealthy. So only they might be telling not to go near to the plant at night.