Salt can injure or kill frogs. Like slugs, frogs have very moist skin, so when they come in contact with salt or a saltwater solution, it causes a burn-like effect.
An excessive amount of salt removes the water from an animal's cells and disrupts an internal equilibrium, which leads to extreme dehydration. Frogs die when they become dehydrated. Even spraying a saltwater solution on the pavement or the plants around your house burn the frogs' feet and legs when they touch the area. Although there are other ways to get rid of frogs, salt is a quick way to kill them.