Ethyl methanesulfonate (CAS 62-50-0): storage and disposal
University genetics and plant biology groups hold ethyl methanesulfonate as a neat liquid, bought in small bottles for mutagenesis work. It is classified as harmful if swallowed, may cause genetic defects and is suspected of causing cancer. Those effects make it a bottle that nobody wants to handle more than once, and a part-used one left behind by a departed researcher is the usual problem.
- CAS number
- 62-50-0
- Form
- Liquid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code, laboratory stock
- 16 05 06*
Harmful or irritant
Serious health hazard
What to do this week
- Without moving anything that looks damaged, 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 anything listed under "Do not store with" on this page. If nothing is listed, that does not prove it is safe with everything.
- If you no longer need it, add it to your disposal list so it can be included in a collection.
Safe storage in a school or lab
In a university research lab the bottle usually sits in a fridge or cupboard that the whole group uses, which is the first thing to reconsider. Because it may cause genetic defects and is suspected of causing cancer, it belongs in a locked cabinet for toxic stock, with a stock record naming who holds the key. Keep it away from oxidisers and acids, and from food and drink areas, including shared group fridges. A tray beneath the bottle, and a sealed outer container, catch a leak before it reaches the shelf. If it leaves the cabinet for a session, log it out and back in.
How to tell it has deteriorated
The liquid gives few signs you can safely judge, so the container is the guide. Check the cap and thread for residue, the bottle for cracks, the label for fading or splashes and the outer container for stains. A lowered level shows vapour or liquid has escaped. A missing stock record, or no name for the person who last used it, is the most common fault in group stores. Do not open an old bottle to look at the liquid. Record the label wording, the cap condition and the approximate volume left, and ask for advice.
How it is disposed of
We arrange this by specialist collection. We do not publish a drain or general waste route for any chemical. It is normally packed in a toxic laboratory pack with compatible chemicals.
A bottle left from a finished project goes out by specialist collection, packed with other toxic organic liquids in a lab pack in UN approved packaging. Waste code 16 05 06* fits a laboratory chemical, with 16 05 08* where it counts as discarded organic chemical outside a lab pack. No one should pour leftovers away, wipe a spill into a drain or attempt to make the liquid safe, since it may cause genetic defects and is suspected of causing cancer. Record who owned the project, the label wording and the volume, and keep the bottle in its outer container.
| Usual EWC code, laboratory stock | 16 05 06* |
|---|---|
| Discarded organic chemical, not a laboratory pack | 16 05 08* |
| Usually classed as hazardous waste | Yes |
The code depends on where the waste came from and what it contains, and classifying it is the producer's duty. 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
Usually held as: neat.
Tell us the container size and how many you hold. An estimate is enough to start with, and some items cannot be priced until someone has looked at them.
Where it is commonly held
Hazard statements
- H302 Harmful if swallowed.
- H340 May cause genetic defects.
- H351 Suspected of causing cancer.
Precautionary statements
- P203 Obtain, read and follow all safety instructions before use.
- P264 Wash hands and exposed skin thoroughly after handling.
- P270 Do not eat, drink or smoke when using this product.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P301+P317 IF SWALLOWED: Get medical help.
- P318 If exposed or concerned, get medical advice.
- P330 Rinse mouth.
- 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
Why does ethyl methanesulfonate need locked storage?
It is classified as harmful if swallowed, may cause genetic defects and is suspected of causing cancer. That puts it with toxic stock, which is held in a locked cabinet with a stock record. A shared group fridge or open shelf does not meet that.
A researcher left a half-full bottle. What do we record?
Record the label wording, the approximate volume, the container condition and the name of the project and person if known. Keep it in its outer container in the locked cabinet. Do not open it or decant it to check the volume.
What should happen to a small leftover of the neat liquid?
It should not be diluted or sent to a drain or sink, and nobody should try to make it safe, since it may cause genetic defects and is suspected of causing cancer. Keep any leftover in a labelled container and include it in the collection request.
