My husband used cif cream inside the oven but i dont think he cleared all the residue out properly before he first used it again - It got most of the food stains out but there are some burnt bits still in there. I think i have managed to get the residue out by wiping down at a later date. Has anyone else used this to clean in an oven? , I have concerns that there may be residue left in there (particularly within the bits of burnt food/stains) and whether it is harmful. i think i am being paranoid but would like other people's input. Thanks.