How does de-icing roads with salt negatively impact the environment?

De- Icing roads using salts can result in Sodium Chloride infiltrating bodies of fresh water which are toxic to the ecosystem. In addition: As road salt dissolves it forms a highly concentrated salt solution. So it is a hypertonic solution outside of plant cells, this then causes the water in the plant cells cytoplasm to move out of the cell by Osmosis to try to achieve dynamic equilibrium. This then creates a situation where the inside of the cells become dehydrated and if this continues it is corrosive and unsafe for plant life.