State Fertilizer Databases
Beginning with Washington State, a handful of states have passed law requiring, at least, the collection and reporting of data on the non-nutritive metals in fertilizers sold within the state. The laws have not gone so far as to require this information be printed on the product label. Instead, the data is available in a state sponsored database. These links are to the state-sponsored databases.
Not all products are registered in a state so if you don't find the product you're looking for in one state's database, try another. Note, however, that even the same-brand fertilizer product listed in any of these states' database may contain different source materials when registered in a different state. In other words, "Ironite" sold in Washington may not be the same source material and/or formulation as sold in New York.