Does Styrofoam release a gas when heated in a microwave oven if so is this gas hazardous to humans?

Question

Does Styrofoam release a gas when heated in a microwave oven if so is this gas hazardous to humans?

Answer 1

Styrofoam is unlikely to decompose in short-term use in a microwave, but it is subject to melting due to spot overheating of vessel contents, something for which microwaves are notorious.  Using Styrofoam containers in microwaves is discouraged for this reason.

Long term unattended use of Styrofoam in a microwave  CAN result in decomposition into all sorts of nasty products, like benzene.

Note that this is an opinion based on limited research.  You would get a much better answer if you asked this one under Chemistry.  I personally would not conduct the experiment to find out for sure.