According to an article in the January-February 2001 issue of Audubon magazine, the United States used more than 16.5 million tons of rock salt to de-ice its roadways in 1999, while Canada uses more than 5 million tons annually.

Entitled "Road Assault," the article explains that this roadway salt has negative side effects on the environment. Road salt can contaminate groundwater, cripple roadside vegetation, and poison some species of birds. Moreover, tasty salt deposits may entice birds, bighorn sheep, elk, and moose to the roadside, thereby increasing the chance they'll be hit by passing vehicles.