Any food or health-related hazards from rust inside microwave?

That is what I'm concerned about, whether holes in the floor of the microwave so one can see the counter below, allows radiation to escape (they say door must be closed!!) would this be dangerous or start a fire on the butcherblock counter??? How do you safely dispose of such microwave if necessary??

That is what I'm concerned about, whether holes in the floor of the microwave so one can see the counter below, allows radiation to escape (they say door must be closed!!) would this be dangerous or start a fire on the butcherblock counter???

A microwave works by basically generating RF energy at microwave frequencies and directing those into the cooking chamber. The walls are all metal to reflect the microwave energy into whatever is cooking. The screen on the inside of the front door also reflects the microwaves (they're too big to fit through the holes in the screen), which allows a way to look inside while the oven is operating.

The plastic coating on the inside is basically for appearance (nice and clean white surface) and for ease of cleaning (it's easier to clean than bare metal). And, microwaves do not affect plastic. The frequency of the microwave energy is basically the resonant frequency of water molecules. So, the microwaves cause water molecules to vibrate, resulting in heating from the inside. That's why you can put something like a bowl of ice cream into a microwave and melt it, while the bowl stays cool (there's no molecules in the bowl itself that are excited by the microwave energy).

So, as long as the microwave works properly to heat whatever they put in it, the peeling plastic or rust shouldn't be an issue. It may look terrible and maybe there's a rusty smell from the exposed metal. But, it's not harming the food, nor is there any danger of the rust contaminating the food, as long as it doesn't flake off and fall into the food while it's cooking