What is the biological risk of using salt on icy roads in parts of the country that have a cold winter season?

Salt has the property to absorb the heat energy of the ice and helps in melting down the ice. It means it lowers the freezing point of the ice. This is the very reason, salt is used to clear the ice clogs in the roads.

When the salts sprinkle on the ice, the ice strats melt and the salt water goes to the nearby water bodies. Here it increases the salt concentration of the water. This result the isotonic water becomes hypertonic.

This higher concentration of water creates problems in osmotic balance in aquatic organisms. The salt by mixing with sail enhance the salinity of the soil. When the plants take extra salt from the soil, it increase the water stress of the plants.

The sprinkling of salt water on the leaves of tree, blocks the pores of the leaves. It disturbs the gas exchange of the plants.

condensation. good luck!