pubs.rsc.org Has an article about ferrous nanoparticles. One of the pulldown menues, which talked about their safety, stated that if the nanoparticles caused problems, they could be deactivated by an MRI or an EMP. THAT WOULD ERASE THEIR PROGRAMMING. In my time I have used reel to reel recording tape often. To erase it, and clean off all the data, one needed to use a deguaser. A tool that emitted a strong magnetic feild in order to take the old magnetic information out of the tape. Could it do the job? Currently Deguassers are being used to erase hard drives. Clorine dioxide solution (food grade, ingested in eater) might oxidized the nano particles. (According to the chlorine dioxide solution group on telegram), But I don't believe that is possible. I would love your positive input...Anyone?