Another point that I would like to add is that I am retired USAF and now currently working as a Civil Service Automotive Technician for the USAF. I am not saying this to say I know more than any of you, so please bear with me and read on.... The Federal Government is very "ANAL" on being environmentally friendly, and the United States Air Force takes "First Place" of all I have seen. I have to cut filters apart every day. The cans are washed out and turned in as scrap metal. The filter cartridges are crushed hydraulically to squeeze oil of the oil, fuel, anti-freeze, or anything else out of them and the crushed filter element is turned in as Hazardous Waste along with the squeezings which is in a seperate barrel. I have cut every name brand known to man and I have never seen anything alarming in any of them. Paper elements or paper elements incased in metal. I did this last week find metal in a Luberfiner filter, however, that was from a '04 Chevrolet Impala Police Car that had spun a rod bearing so it would stand to reason that it would have metal particles in it. Still have not seen anything alarming in cutting any of them apart and I cut them daily.