Using salt on your sidewalks for de-icing can be harmful for the environment. Salt can be toxic for animals, trees and plants and it also can contaminate groundwater. It is estimated that 11 million tons of salt is used every year in the United States. Safe and natural alternatives that add traction to the icy areas around your home are fireplace ash (make sure it is cold) and spent coffee grounds. As a bonus, both of these substances will act as fertilizer if they make their way to your lawn.