RFID tags injected under the skin of a human being or animal do not send out any signals. They are passive tags that require energy from a reader, and reflect back a signal to that device. So unless someone held a reader within a foot of the tag under your skin, no one could track you or receive any data from the tag.
As for removal, I would recommend that you see a doctor, who can make a small incision at the site at which you had the device originally implanted—there should be a mark there—and simply remove it.
—Mark Roberti, Founder and Editor, RFID Journal
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