A friend of mine has been recommending this Peruvian Seabird Guano fertilizer to me as a natural alternative that is good for sensitive plants (he uses it on his miniature orchids, bromeliads, and Cephalotus). I bought a bag, and was just reading the notice on the back which says to check www.aapfco.org/metals for info about metals content of the product. I went to this website and looked at what the company reported to the state of Oregon. They show 8.58 ppm Arsenic, 3.56 ppm Cadmium, and 1ppm Lead. These seem like potentially very dangerous levels for people with growing setups where there is not a lot of flushing going on (terrariums, undrained containers, tray systems that don't get washed, raised garden beds). I just thought I should get the word out because my friend had this product recommended to him on one of the Dendro boards (he does Dart Frogs) where everyone is growing in closed systems. I would be very cautious about this product.