you need to remember, that those RFID tags are passive, i.e. no power source. To read them, you need to supply a magnetic field to energize them, so,
ok, in theory, they could be injected into you, but there is no way (currently) to keep track of you...... You can't be tracked via GPS, (there are no
batteries small enough, nor can you manufacture a GPS antenna small enough (that is just pure physics) ) unless you are in proximity of a high enough
magnetic field to energize them, etc.... and even then, the Magnetic field has to come from antennas (loops) withing a couple of centimeters from you
.... I can refer you to these documents having the specifications to RFID devices.
www.ti.com...
www.idtechex.com...
www.motorola.com...
edit on 12/11/2011 by Hellhound604 because: (no reason given)