It’s funny, I’m more paranoid about contact with my birds’ food than I am about contact with their feces. Bird poop is just not something that is that gross to me and not something that I’m worried about causing me illness (still needs to be gotten rid of before the stink grows).  Whereas it is nigh impossible to get store-bought seed or pellets without some quantity of wheat.  I tend to avoid those where it is obvious that the amount is significant, but either way … it triggers my substance handling paranoia.