We have been using salt to keep winter roads free of ice and snow since the late 1930s. In the United States alone, some 20 million tons of salt are applied to roadways each year. And while its use has real benefits in terms of safety and navigation, there have been cumulative costs to the environment, including degrading freshwater resources and contaminating groundwater.
Augmenting food with preservatives is not a recent practice. For thousands of years, we have canned fruits with sugar, preserved meats with salt, and pickled vegetables so that they could keep in hot humid environments.
Snow season is here. The chances are good you’ll find yourself behind a truck spreading salt on the roads in an attempt to deice them. You may even try a little salt on your own front porch. Annually we spread about 20 million tons of road salt in the U.S., and we’ve been doing it since the late 1930s.