Microwaved foods themselves do not retain trace amounts of radiation. The radiation emitted by a microwave oven is non-ionizing radiation, specifically in the form of microwave electromagnetic waves. These waves excite water molecules in the food, generating heat and cooking the food.
During the cooking process, the microwave radiation is contained within the oven and does not remain in the food once the microwave is turned off. Once the microwave stops operating, the radiation dissipates rapidly. Therefore, there is no residual radiation left in the food after it has been cooked or heated in a microwave oven.
It's important to note that microwave ovens are designed with safety measures to prevent leakage of microwave radiation. When used according to the manufacturer's instructions and maintained properly, microwave ovens are considered safe for use in the home. However, it is recommended to ensure that the microwave oven is in good condition, has a functioning door seal, and is not damaged or modified in any way that could affect its safety features.