Low temp causes heating coil to spark and leave...

Question

We have an old frigidaire oven (can't find the model or serial number) in
our rented house. After running it for a while on a low temperature, 200
degrees, the heating coil began to spark. I turned off the oven, but now
there is a white powder residue near the spark area. What is wrong with this thing? Can I trust it not to burn down the house?