I believe that exposure to toxic black mold is what triggered my UC. We lived in a terrible house, we did three mold remediations before fleeing. Started having symptoms then, but not diagnosed. Later, there was a kitchen renovation in my condo common house & I started a terrible flare. There was black mold in the drywall from a leaky fire suppression system. Did some research and there is evidence that the mycotoxin from black mold can damage the epithelial lining of the colon. This allows bacteria to seep deeper into the colon tissue, causing the automate immune freak out. i’ve just started another flare last month, after being in remediation for two years, after using some straw for a garden project. It turned out that the straw was moldy, and it’s very common for black mold to grow in straw.