My beloved cast iron teapot that I have had for years seems to have turned on me. It has an acrid sort of smell and is imparting a bad flavor to my tea. I fear that some less than dignified tea may have been left to sit in it for a long time. I've tried rinsing it with boiling hot water repeatedly. Today I even used a few drops of dishsoap to see if that would help... but no. It seems like the problem is deeper.
Any ideas for resurrecting it? I don't have any baking soda (and it's really hard for me to get as I live in a country that doesn't believe in it).