Bromine (CAS 7726-95-6): storage and disposal
Dense, red-brown and fuming, bromine is usually held in sealed glass ampoules or specialist bottles in school, college and university stores. It is fatal if inhaled, causes severe burns, acts as a strong oxidiser and is very toxic to aquatic life. Handling turns on whether the first seal has held. That is why ampoules sit in secondary containment, and why the inside of that outer container matters more than anything printed on the label.
- CAS number
- 7726-95-6
- Form
- Liquid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code
- 16 05 06*
Corrosive
Acute toxicity
Hazardous to the environment
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
Sealed glass ampoules are the usual form, packed in an outer container with cushioning, and an unopened ampoule is the safest state this liquid will ever be in. A part used bottle is more of a worry, because it corrodes metal and seals, and caps fail in time. Both belong in the locked toxic cabinet with a stock record. What gets overlooked is the company it keeps in a busy prep room. Acetone and ethanol react violently with it, and so do ammonia solution, aluminium powder, magnesium ribbon, sodium metal and potassium metal, several of which often live nearby. Mercury also needs to be elsewhere. Avoid metal trays and metal shelving directly beneath it, since escaping vapour attacks them first.
How to tell it has deteriorated
Brown colour inside the outer container is the first thing to look for, and where it sits is what counts. An intact ampoule always shows brown vapour above the liquid, so that alone means nothing. Brown vapour outside the ampoule, in the secondary container, means the seal has failed. If you can see that, do not open the secondary container, and call for specialist help. On bottles, a brittle cap and staining around the neck are the signs, along with rust or staining on nearby shelving and hinges. The element itself does not break down with age in the way an organic reagent might. What fails over time is whatever is holding it in.
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.
It leaves by specialist collection, and only that way. An intact ampoule and a failed bottle are very different jobs, so say which you hold, how many, and what the outer container looks like. Visible vapour in the secondary container should be mentioned straight away, as a specialist may have to see it before any packing can be planned. It cannot be put into a sink, a drain, a general waste bin or a skip, and nobody should try to treat it first. Grouping is the awkward part: in a collection it has to travel away from solvents, ammonia and reactive metals. Code 16 05 06* usually fits school and university stock. In Scotland the note travelling with it is a special waste one.
| EWC code, laboratory chemicals | 16 05 06* |
|---|---|
| Discarded inorganic chemical, not a laboratory pack | 16 05 07* |
| 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.
- AcetoneBromine reacts violently with ammonia, reactive metals and many solvents.
- Aluminium powderBromine reacts violently with ammonia, reactive metals and many solvents.
- Ammonia solutionBromine reacts violently with ammonia, reactive metals and many solvents.
- Calcium hypochloriteToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
- EthanolBromine reacts violently with ammonia, reactive metals and many solvents.
- 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.
Show 8 more
- Magnesium ribbonBromine reacts violently with ammonia, reactive metals and many solvents.
- MercuryMercury forms amalgams or unstable compounds with these materials.
- Nitric acidToxic stock is stored apart from acids. Several toxic salts release toxic gas in contact with acid.
- Potassium metalBromine reacts violently with ammonia, reactive metals and many solvents.
- 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.
- Sodium metalBromine reacts violently with ammonia, reactive metals and many solvents.
- 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: liquid in sealed ampoules.
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
- H314 Causes severe skin burns and eye damage.
- H330 Fatal if inhaled.
- H400 Very toxic to aquatic life.
Precautionary statements
- P260 Do not breathe dust, fume, gas, mist, vapours or spray.
- P264 Wash hands and exposed skin thoroughly after handling.
- P271 Use only outdoors or in a well-ventilated area.
- P273 Avoid release to the environment.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P284 In case of inadequate ventilation wear respiratory protection.
- P301+P330+P331 IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.
- P302+P361+P354 IF ON SKIN: Take off immediately all contaminated clothing. Immediately rinse with water for several minutes.
- P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing.
- P305+P354+P338 IF IN EYES: Immediately rinse with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
- P316 Get emergency medical help immediately.
- P320 Specific treatment is urgent (see supplemental first aid instruction on this label).
- P321 Specific treatment (see supplemental first aid instruction on this label).
- P363 Wash contaminated clothing before reuse.
- P391 Collect spillage.
- P403+P233 Store in a well-ventilated place. Keep container tightly closed.
- 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
Our ampoule looks brown inside. Does that mean it is leaking?
Brown vapour above the liquid inside a sealed ampoule is normal and does not mean it is leaking. Look instead at the space around the ampoule, inside the outer container. Brown there means the glass has failed, and the outer container should then stay closed while you call for specialist help.
Should we open the outer tin to check the ampoule before collection?
There is no need, and with an opaque outer container it is better left shut. Opening it could release vapour you had no way of seeing beforehand. Describe the outer container as it stands, with its label and any staining, when you arrange the collection.
What about a part used bottle with a brittle cap?
Leave that cap alone, because a brittle cap may break if it is turned or knocked. Avoid moving the bottle if you can see staining or vapour. Describe the cap and the level of liquid when arranging collection, and ask for specialist help if vapour is visible.
Does bromine go off with age?
The element does not really go off. Its effect is on what surrounds it, because it corrodes metal and seals. Age therefore shows as brittle caps, staining on shelving and brown vapour where there should be none, and a very old bottle needs looking at with that in mind.
