Mercury is confirmed to be too dangerous and toxic for sewer disposal. Yet it's still being used in dental fillings and still being carelessly disposed of in the community water supply across the world.

EPA, Council of the European Union tighten rules on dentists' use of mercury | Bellingham Herald

Anyone who already has mercury fillings, which are also called Amalgams, Silver Fillings, Metal Fillings ... do not let your dentist remove them without utilizing the proper removal protocol. Drilling into a mercury filling releases immeasurable amounts of toxic particles and toxic vapors into your body that travel through your entire blood stream into every organ of your body. The protocol can be found on the link below. Do not hesitate to copy this link and bring it to your dentist! It is your health that is at stake.

If your dentist thinks it's rubbish or not necessary, they are 100% misinformed and are too lazy to change old habits and too cheap to purchase the proper equipment. Seek a different dentist who has your health in mind and already performs the protocol.

The Safe Mercury Amalgam Removal Technique (SMART) - IAOMT