Hexachloroethane (CAS 67-72-1): storage and disposal
Hexachloroethane is a crystalline solid that survives in school, college and university stores as legacy smoke tablets. It irritates skin, eyes and airways, is suspected of causing cancer and is very toxic to aquatic life with long lasting effects. A tablet is a made-up product, not a bottle of pure chemical, so the label's list of contents matters more than the name alone.
- CAS number
- 67-72-1
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Warning
- Usual EWC code
- 16 05 06*
Harmful or irritant
Serious health hazard
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
The hazard that decides where it goes is the combination of a cancer classification and a very toxic effect on water life, so a locked cabinet with a stock record, kept away from food and drink areas and from acids and oxidisers, is right. Smoke tablets may be in their original card tube or foil, and that packaging should stay in place with the label legible. Keep tablets dry and away from heat sources, and do not break or crush one to see inside. Anyone finding a loose tablet should leave it where it lies and report it.
How to tell it has deteriorated
What a technician sees first is the packaging: card tubes gone soft, foil corroded, labels faded and tablets crumbling. This solid sublimes slowly, so crystals can re-form on the inside of a jar lid or on the shelf above, and a camphor-like smell may reach the cabinet. A cracked or powdery tablet or one stained by its wrapper should be left alone. A tablet is a pressed mixture, and the ingredient list on the box may be missing, in which case the item should be described as unknown mixture. Keep each tablet in its pack.
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.
Record what is on the label of each hexachloroethane item before asking for a collection: the product name, the listed ingredients if any, the number of tablets and the condition of the pack. Because it is a legacy smoke product, say plainly that it is one. It goes by specialist collection only, and it must never be burned, crushed, buried or washed away, nor should anyone try to test one. The list code is 16 05 06* for packed stock, and a loose discarded organic chemical not sent in a pack can use 16 05 08*.
| EWC code, laboratory chemicals | 16 05 06* |
|---|---|
| Discarded organic chemical, not a laboratory pack | 16 05 08* |
| 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: legacy smoke tablets.
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
- H315 Causes skin irritation.
- H319 Causes serious eye irritation.
- H335 May cause respiratory irritation.
- H351 Suspected of causing cancer.
- H410 Very toxic to aquatic life with long lasting effects.
Precautionary statements
- P203 Obtain, read and follow all safety instructions before use.
- P261 Avoid breathing dust, fume, gas, mist, vapours or spray.
- P264 Wash hands and exposed skin thoroughly after handling.
- P264+P265 Wash hands and exposed skin thoroughly after handling. Do not touch eyes.
- 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.
- P302+P352 IF ON SKIN: Wash with plenty of water.
- P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing.
- P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
- P318 If exposed or concerned, get medical advice.
- P319 Get medical help if you feel unwell.
- P321 Specific treatment (see supplemental first aid instruction on this label).
- 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.
- 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
What should we do with old smoke tablets containing hexachloroethane?
Leave them in their original packaging in a locked cabinet, record the label details and condition, and arrange specialist collection. Do not light, break or test them, and never bin or bury them.
Why do crystals appear inside the tablet jar?
Hexachloroethane slowly sublimes and the vapour settles as crystals on cooler surfaces. It is a sign of age and of a loose lid. Record it, keep the jar closed in the locked cabinet and do not scrape the crystals away.
Is a smoke tablet the same as the pure chemical?
No. A smoke tablet is a made-up product that may contain other ingredients. Describe it by its label and ingredient list as well as by the hexachloroethane name, and if the label is lost, say so.
