Chemicals

This may appear twice as I did it once and couldn't find where it went!! I needed some sterling silver cleaner. I purchased TARN-X. While reading the instructions on the back of the bottle it said WARNING: This product contains thiourea, a chemical known to the state of California to cause cancer. It didn't say it may cause cancer it said it does cause cancer. They keep telling us that they are working to cure cancer then why is this allowed on the market? Perhaps, this is not available in the state of California? I am going to take it back and tell them why I am returning it. I don't expect to get any answers here but just wanted to vent. Hugs, Sandy