They said it wasn't likely a toxin, or at least there were no toxins that screening picked up on. But could some other fungus/mold or other pathogen infect the

They said it wasn't likely a toxin, or at least there were no toxins that screening picked up on. But could some other fungus/mold or other pathogen infect the people there or could they accumulate a toxin that wasn't screened for? Just how clean did they get and keep that place at?