Ethyl carbamate (CAS 51-79-6): storage and disposal
Ethyl carbamate, also called urethane, is a white crystalline solid that survives in school, college and university stores as a legacy anaesthetic and laboratory reagent. It may cause cancer and is harmful if swallowed. Few current staff will have used it, and its everyday name is easy to confuse with polyurethane products, so stock is often found without anyone knowing what it is for.
- CAS number
- 51-79-6
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code
- 16 05 06*
Harmful or irritant
Serious health hazard
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
Start with what it must be kept apart from. Toxic stock goes away from acids and from oxidisers, since a reaction with an oxidiser could release hazardous vapours and acid contact is a separate concern. Keep it in a locked cabinet with a stock record, away from food and drink areas, and tell staff in the department what the jar is. Do not store it with polyurethane foams, varnishes or resins that happen to carry the word urethane, which are quite different materials. Keep the lid tight, put the jar on a tray and avoid unnecessary handling. A jar with no owner should be given one.
How to tell it has deteriorated
The container and label tell you the most. Old jars often have a faded or brittle label, a cap thread dusted with crystals, a seized lid and a stock record that is long out of date. Because this solid gives few visible signs of age, do not rely on colour or smell. Crystals that have clumped or look damp point to a loose lid, and cracked glass is a reason to place the jar in a tray before it is moved. A jar labelled only urethane, with no date and no owner, is treated as unknown legacy stock and left unopened.
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.
What must not be done with it is simple: no one pours it into a sink, puts it in the bin, burns it or dissolves it to be rid of it, because it may cause cancer. It leaves by specialist collection in a lab pack with compatible solids, described under waste code 16 05 06*, or 16 05 08* for a discarded organic chemical outside a pack. Record every name on the label, such as urethane, carbamic acid ethyl ester or O-ethyl urethane, plus the jar weight and the state of the lid. Say that it is legacy stock.
| 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 stock.
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
- H302 Harmful if swallowed.
- H350 May cause cancer.
Precautionary statements
- P203 Obtain, read and follow all safety instructions before use.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P318 If exposed or concerned, get medical advice.
- P405 Store locked up.
- P501 Dispose of contents and container in accordance with local, regional, national and international regulations.
- P264 Wash hands and exposed skin thoroughly after handling.
- P270 Do not eat, drink or smoke when using this product.
- P301+P317 IF SWALLOWED: Get medical help.
- P330 Rinse mouth.
Substance as classified, dilutions may differ.
Questions
Is urethane the same as ethyl carbamate?
Yes. Urethane is an older name for ethyl carbamate, and carbamic acid ethyl ester is another. Do not confuse it with polyurethane products, which are different materials. Record every name printed on the jar.
Why is ethyl carbamate found in so many old stores?
It was an anaesthetic and laboratory reagent in the past and was rarely used up. Many stores have one jar that nobody now uses. List it as legacy stock when you ask for collection.
Can we throw away a jar that is nearly empty?
No. Even a small amount in a jar is classed as able to cause cancer. Keep the lid on and the jar in its labelled place, and declare it with the rest of the stock.
Where should it be kept until collection?
In a locked cabinet with a stock record, in a tray, away from food and drink areas, acids and oxidisers. Tell colleagues what it is, so no one opens or moves it without knowing.
