@jw9 Actually, I worked in a foundry for many years! That environment, with silica sand, and ferrous sulphate, and manganese fumes, csused lung cancer, and like a ‘coal miner’s’ lungs, for many, according to medical records. that were kept by the company I worked for. So, I would think that you may be correct, that mixing chemotherapy chemicals, and especially with getting a metallic taste in your mouth, likely contributed, and/or may have caused a medical disgnosis that you have now! I have several neurological and sinus problems, that I believe contributed or caused at least one of my diagnosis! So sorry that you have to go through the difficult medical path, that you are on!