O-rings, those circular, donut-shaped seals, are primarily used to prevent leaks of fluids or gases in various applications by acting as a seal between two surfaces, such as pipes, tubes, or cylinders. The rubber material of the O-ring can contain harmful substances which may be released during use. If such an O-ring comes into direct contact with food, it is possible that these substances are being transferred from the rubber to the food. For this reason, not all O-ring materials are suitable for food applications.