Hi plllog...

Not sure if you saw my reply to you about cleaning your oven on my "cleaning stainless steel revisited", so:

* In case you've never tried it, baking soda and water worked amazingly on my toaster oven! I made kind of a slurry and wiped it on, let it sit, and scrubbed off. It did scratch the plastic part, so test it out.

* Also, Arm & Hammer oven cleaner is rated non-toxic by Consumers Union.

* Another suggestion I read on chowhound.com is to put a large roasting pan of water on "low-medium" heat (?) in the oven and letting it steam for an hour before scrubbing. Seems like this might help with the convection fan area.

Perhaps someone else has a natural remedy since you have sensitivity to chemicals.

HTH :)