Injectable polytetrafluoroethylene (Polytef) has been used in many patients for vocal cord augmentation and for the management of urinary incontinence since the early 1960s and non-injectable forms have been used for sutures, hernia repair, replacement of the stapes, hip prostheses, cardiac valves and vascular grafts. Since 1984, many children have been treated with subureteric Polytef injection for the management of vesicoureteric reflex. Its use in young patients has heightened the concern about particle migration and carcinogenesis, particularly in view of the fact that the substance may be in the patient for decades. The available evidence does not confirm a significant carcinogenic effect in humans; rather it suggests that, if there is a risk, it is extremely low. However, human specimens, taken decades after the implantation of Polytef, and long-term, non-rodent animal experiments are needed to substantiate the probable safety of Polytef in children.