Can I Compost Rain Barrel Sludge

Answer from MR: My only serious concern might be if cats or raccoons have been pooping on your roof, but you would probably be able to distinguish that from algae and dust. And birds poop everywhere all the time, including in and on our gardens, without generally causing problems. My suggestion would be to trust your hunches, include it in your compost, and wash your food well if you're eating from your garden. Thanks for your question. I'm sure others will offer their opinions.