
Extract the answer to the question from the following context.
Question: What is not a potential use of hydrogen mixed with nitrogen: leak detection or E949?
Context: In more recent applications, hydrogen is used pure or mixed with nitrogen (sometimes called forming gas) as a tracer gas for minute leak detection. Applications can be found in the automotive, chemical, power generation, aerospace, and telecommunications industries. Hydrogen is an authorized food additive (E 949) that allows food package leak testing among other anti-oxidizing properties.

E 949
