Why is arsenic poisonous

Arsenic is one of the oldest and best known of poisons. It is so well known, in fact, that when the wonderful Frank Capra comedy Arsenic and Old Lace was released, everyone knew that it was going to be a murder mystery in which someone would be poisoned. In fact, it has even been rumoured that Napoleon died from arsenic poisoning, the arsenic coming from the green dye on his wallpaper. We deduce that even a small amount of arsenic will cause death, or at least an unpleasant and lingering illness. 

Improper numbers of electrons in the relay cycles cause them not to work properly, causing a breakdown of those bodily functions, which require exact amounts of charge to flow. If the nervous system fails, then the lungs are not instructed how to work, the heart is not told to beat, etc., at which point death is not too far away. 

But arsenic is more subtle a poison than simply a reducing or oxidizing agent. Arsenic is a metalloid from Group V(B) of the periodic table, immediately below the elements nitrogen and phosphorus, both of which are vital for health. 

Unfortunately, arsenic is chemically similar to both nitrogen and phosphorus, and is readily incorporated into body tissues following ingestion. Arsenic effectively tricks the body into supposing that straightforward incorporation of nitrogen or phosphorus has occurred. 

Arsenic and nitrogen compete for the electrons participating in the natural electron-relay cycles in the body. The number of electrons transferred by nitrogen depends on the number of arsenic atoms competing for them. 

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