What is the requirement for implements that contact mucous membranes?

The requirement for implements that contact mucous membranes is that they must be sterilized. This is crucial because mucous membranes are delicate and highly susceptible to infection; they provide an entry point for pathogens. Sterilization is the process that completely eliminates all forms of microbial life, including spores, which is essential when an instrument is introduced into an area of the body that isn't protected by skin barriers.

In the context of skin care and aesthetics, using sterilized implements significantly reduces the risk of transmitting infections or causing complications. The other options, while they may have relevance in different contexts, do not adequately ensure the same level of safety as sterilization. For instance, being sanitized or cleaned with soap and water might reduce microbial counts but does not guarantee the complete eradication of harmful pathogens, especially in situations involving mucous membranes. Discarding implements can be used in certain one-time scenarios, but sterilization provides a safer, reusable alternative where appropriate.