In winters, they use salt to melt the snow on the streets. Can something else be used instead?

I have read that salt is harmful for some type of materials, so is there a better alternative? Or if not an alternative which could replace salt, can ANYTHING else, which is commonly available, be used to melt snow on roads?

One of my acquaintances who went to study in Europe told me authorities over there have been experimenting with some byproduct of cheese as a more environment-friendly way to melt ice. He claimed that chlorine-based salt which is generally used to melt snow, has negative ramifications on aquatic life.