Potassium Nitrate is primarily used as a fertilizer, as is calcium nitrate. Sodium nitrate is also a component of fertilizers, but it's not as popular any more.

Potassium Nitrate is primarily used as a fertilizer, as is calcium nitrate. Sodium nitrate is also a component of fertilizers, but it's not as popular any more. If you're concerned about the impact of these being released into the environment, you should realize that we're already doing it deliberately on farms all over the country.