In India, it's common for scavengers to rummage through landfills in search of old syringes they can sell back to clinics. According to one study, out of the 4 to 5 billion injections that are administered each year in India, at least 2.5 billion are unsafe, meaning these second-hand syringes are potentially contaminated with blood-borne diseases such as as HIV or hepatitis.
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David Swann, of England's Huddersfield University, has designed the ABC syringe in effort to reduce those alarming figures and help save thousands of lives each year. The syringe uses an ink that is sensitive to carbon dioxide. When sealed in a protective environment, the shell of the syringe remains clear. Once it's used and the seal has been broken, the syringe case changes color to alert anyone who sees it, that it's potentially contaminated and should not be used.
"When you compare a sterile syringe just out of its packaging with a syringe that's been washed, how do you determine the difference?" Swann told CNN. "We conceived an intelligent ink that, if exposed to air by taking it out of the package or if the package is breached that would activate it and turn it red."