Sodium acetate is a ionic compound with the chemical formula C2H3NaO2 commonly used in labs--especially biochemistry labs. It acts as a buffer, a chemical that stabilizes the pH of a solution, and also finds use in the tanning, textile and petrochemical industries, among others. Sodium diacetate--a compound formed by mixing vinegar and sodium acetate--is a common food additive.
Chemical suppliers and manufacturers typically produce sodium acetate by reacting acetic acid (vinegar) with sodium hydroxide or sodium carbonate; it can also be produced without any special equipment by simply mixing vinegar and baking soda. If sodium hydroxide is used in its manufacture, production can pose some hazards since sodium hydroxide is a highly caustic compound. The reaction of vinegar with baking soda, however, is not hazardous.
The FDA classes sodium acetate under the "Generally Recognized as Safe" category when used as a food additive. Sodium diacetate is a common preservative and flavor enhancer made using sodium acetate and is also generally recognized as safe. In general, sodium acetate is not believed to be harmful in small quantities, nor is it considered harmful to the environment at low levels.
Median Lethal Dose
One measure sometimes used to assess the toxicity of a substance is the median lethal dose, or LD50--the amount of chemical per kilogram of body weight needed to kill half of a population of rats that ingest it over a set period of time. According to the Material Safety Data Sheet from Abbey Chemicals, a chemical supplier, the LD50 for sodium acetate is 3530 milligrams per kilogram, meaning that the median lethal dose in rats is 3530 milligrams per kilogram of body weight--a very large amount to consume. The LD50 for table salt is 3000 milligrams per kilogram by comparison.
Sodium acetate, just like vinegar, is considered an eye irritant and a mild skin irritant. Sodium acetate can cause irritation if it gets in your eyes or is rubbed it into your skin.
Sodium acetate is potentially flammable and should not be brought in contact with open flames. It reacts violently with some strong oxidants and strong acids like nitric acid or potassium nitrate. Under the right conditions, a mixture of potassium nitrate and sodium acetate will explode, so sodium acetate must be stored separately from potassium nitrate and other strong oxidants.