Sodium fluoride (CAS 7681-49-4): storage and disposal
Dental surgeries hold sodium fluoride as varnish and gel, while school, college, university and pathology stores keep the plain solid. Pure sodium fluoride is classified as toxic if swallowed and irritating to skin and eyes. Dental varnishes and gels are formulated products whose classification depends on their complete composition. The mix of tubes in the surgery cupboard and a jar of crystals in a prep room means the same name covers very different waste.
- CAS number
- 7681-49-4
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code
- 16 05 06*
Acute toxicity
What to do this week
- Check the label is readable and write down the opened date if it is not already there.
- Check it is stored as toxic stock and apart from the items listed under "Do not store with".
- If you no longer need it, add it to your disposal list so it goes on the next collection.
Safe storage in a school or lab
Dental varnish and fluoride gel arrive in small tubes, trays and unit-dose packs, and surgeries often keep opened and out-of-date tubes in a drawer. Pure sodium fluoride stock should be secured in a locked cabinet with a stock record, away from food and drink areas. Dental varnishes and gels should be stored according to their product safety information. Keep acids apart, since acid contact with fluoride salts can release a dangerous gas, and keep oxidisers clear too, because toxic and oxidising stock are stored apart. Prep rooms should not keep the solid beside general salts or on an open shelf. A separate labelled tray for tubes and another for the solid prevents mix-ups.
How to tell it has deteriorated
Out-of-date tubes are the most common sign of old fluoride stock: split seals, crusted nozzles, hardened varnish and faded print. The solid shows few visible signs, but clumping, damp or staining around the cap shows the jar has been open to air. Check the label first, then the cap and the record. A product sold under a trade style name, such as a neutral gel, may not say sodium fluoride clearly, so write the active ingredient on the shelf record. Do not open a jar just to look.
How it must be disposed of
By specialist collection only. It never goes down the drain or into general waste. It is normally packed in a toxic laboratory pack with compatible chemicals.
Surgery stock and prep room stock are described separately: tubes and gels are counted by container, and the solid by weight. A dental practice uses the healthcare code and a school or university uses the laboratory chemical code. Record the quantity, the container condition and the expiry date where printed. Sodium fluoride is toxic if swallowed, so it must not go in clinical waste, a sink or a skip, and nobody should try to treat it with acid. The specialist carrier packs it apart from acids and oxidisers.
| EWC code, laboratory chemicals | 16 05 06* |
|---|---|
| Discarded inorganic chemical, not a laboratory pack | 16 05 07* |
| Human healthcare setting | 18 01 06* |
| Hazardous waste | Yes |
The code depends on where the waste came from and what it is mixed with. Use the waste code finder to see why.
Do not store with
- OxidiserToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
- AcidToxic stock is stored apart from acids. Several toxic salts release toxic gas in contact with acid.
Named chemicals to keep apart
- Acetic acidToxic stock is stored apart from acids. Several toxic salts release toxic gas in contact with acid.
- Calcium hypochloriteToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
- Hydrochloric acidToxic stock is stored apart from acids. Several toxic salts release toxic gas in contact with acid.
- Hydrogen peroxideToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
- Nitric acidToxic stock is stored apart from acids. Several toxic salts release toxic gas in contact with acid.
- Potassium nitrateToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
- Potassium permanganateToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
- Sulfuric acidToxic stock is stored apart from acids. Several toxic salts release toxic gas in contact with acid.
Common quantities we collect
Usually held as: solid, dental varnish.
Part-used bottles and full containers are both fine. Tell us the size and how many, and an estimate is enough for a first price.
Where it is commonly held
Hazard statements
- H301 Toxic if swallowed.
- H315 Causes skin irritation.
- H319 Causes serious eye irritation.
Precautionary statements
- P264 Wash hands and exposed skin thoroughly after handling.
- P264+P265 Wash hands and exposed skin thoroughly after handling. Do not touch eyes.
- P270 Do not eat, drink or smoke when using this product.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P301+P316 IF SWALLOWED: Get emergency medical help immediately.
- P302+P352 IF ON SKIN: Wash with plenty of water.
- P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
- P321 Specific treatment (see supplemental first aid instruction on this label).
- P330 Rinse mouth.
- P332+P317 If skin irritation occurs: Get medical help.
- P337+P317 If eye irritation persists: Get medical help.
- P362+P364 Take off contaminated clothing. And wash it before reuse.
- P405 Store locked up.
- P501 Dispose of contents and container in accordance with local, regional, national and international regulations.
Substance as classified, dilutions may differ.
Questions
Can expired fluoride varnish go in the clinical waste bin?
No. Expired fluoride varnish should be described by its product name and formulation rather than classified solely by the presence of sodium fluoride. Its waste classification is confirmed from the product information before specialist collection. Use the healthcare code for the surgery.
Why must acids be kept away from sodium fluoride?
Acid contact with fluoride salts can release a harmful gas, which is why toxic stock is stored apart from acids. Keep them on separate shelves in separate cabinets.
Does the solid need locking away in a school?
Yes. It is toxic if swallowed, so keep it in a locked cabinet with a stock record, away from food areas, acids and oxidisers, and check the cap whenever the stock is counted.
