A Florida company wants to implant its Radio Frequency Identification tags in immigrants and guest workers so they can be identified at the workplace. Scott Silverman, chairman of the Delray Beach-based VeriChip Corporation, said in a "Fox & Friends” TV interview that its RFID implant could be used to register workers at the border, and then verify their identities on the job. Illegal immigrants could then be readily distinguished from those who registered. Silverman said: "We have talked to many people in Washington about using it.” The VeriChip RFID tag is about the size of a large grain of rice and can be injected directly into the body. An antenna in the chip sends data, according to the Web site Technovelgy.com. The chip doesn’t require a battery and has a virtually unlimited lifespan. RFID tags have been used to identify livestock, laboratory animals and pets, but privacy advocates have expressed concerns about the technology being used in human beings. VeriChips are legal for implantation in people in the U.S., although a bill now under consideration in the Wisconsin legislature would ban mandatory implantation of the chips.