Problem with CS? Also cat UTI

I bought CS at the recommendation of a lady at a health food store. I had never heard of it before. I purchased it for my cat who has a chronic UTI problem. I was teling a freind of mine about it and she said that her mother used to take it years ago and that it was taken off the market because it was harming people. She said however, it may have been refined/improved since that time. Does anyone know anything about problems with CS in past years? Also has anyone had any success with using CS to treat feline UTI?