There are actually several dangers here.
The Sodium (Na) is a highly reactive metal.
Because both highly reactive, they may combine explosively.
They combine to form Sodium Chloride (NaCl) – which is common ordinary table salt.
Salt can be used to kill a slug. A slug exposed to salt may die because the salt may “draw the water out” of the slugs cells by osmosis – causing the cells/slug to shrivel up (by plasmolysis) and die.
November 25, 2017