sodium nitrate solution is a colorless, odorless salt that dissolves in water. It is used in the manufacture of potassium nitrate, fertilizers, explosives and to preserve meats. Sodium nitrate is also useful in the production of high-strength glass and for the etching and purification of metals. It is a moderately strong oxidizer, toxic by ingestion and inhalation, and it promotes burning when exposed to flame.
It is also an excellent lubricant and fire-retardant. It is a common ingredient in fireworks. It is also used in the manufacture of the compound nitrous oxide, which is commonly known as laughing gas.
Nitrates and nitrites (such as those found in processed meat products) can cause heart disease. But they also prevent harmful bacteria from growing. This occurs because nitrates are converted to nitric oxide in our bodies, which causes blood vessels to dilate.
Research shows that low levels of nitrate ingestion are safe for humans. In fact, a healthy diet provides most of the nitrates people need to maintain cardiovascular health. But people should avoid nitrates from processed meats, which are linked to stomach, esophageal, lung and pancreatic cancers.
A good way to understand the safety of a chemical is to look up its Material Safety Data Sheets (MSDS) online. They contain detailed information, such as LD50 — the lethal dose for 50% of test animals. You can find the MSDS for most chemicals by entering their name into a web search engine.