Concerns about the impact of RFID technology on the recycling of glass have emerged in the industry. "The core of the RFID matter is that tags contain silicon chips," says Pete Grayhurst. "If the silicon stays with the glass through the recycling chain and into the glass furnace it melts at a different rate to the glass, which can result in silicon "balls" in new packaging." These can be weak spots, especially in pressurised containers. Analysis of the current range of passive security tags has highlighted other issues concerning glass quality and colour. Substances such as chromium iron and cobalt can colour glass, even when present in small quantities. RFID tags can also be difficult to remove and can break up into small pieces during the glass recycling process, making them hard to detect.
