Phenylmethylsulfonyl fluoride (CAS 329-98-6): storage and disposal
Phenylmethylsulfonyl fluoride, known as PMSF, is a protease inhibitor kept in university protein and cell biology labs as a white crystalline solid. The recorded hazards are H301, toxic if swallowed, and H314, severe skin burns and eye damage. Those two statements decide where it lives and who can reach it, and its sensitivity to water decides how old stock behaves.
- CAS number
- 329-98-6
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code, laboratory stock
- 16 05 06*
Corrosive
Acute toxicity
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
A toxic corrosive solid belongs in a locked cabinet with a stock record, and PMSF is no exception even though a gram bottle looks small. Keep it away from food and drink areas, from acids and from oxidising agents. A leak could bring it into contact with either, so give it a separate shelf. The bottle must stay tightly closed and dry, because PMSF reacts with water and a humid cupboard slowly ruins it. In a university lab the working bottle often moves between a bench and a fridge, so each move is a chance for damp to get in. Keep the opening date on the label.
How to tell it has deteriorated
The crystals should be white and free flowing. A damp bottle shows its history. The solid clumps and sticks to the glass, and a crusted cap thread shows where moisture and powder have mixed. Because the substance reacts with water, a bottle that has absorbed damp may have lost its action as an inhibitor with no clear visual warning, so a failed protein preparation is the only other clue. Reaction with water can also form acidic, fluoride-containing breakdown products, so damp stock should be treated as no less hazardous than fresh stock. Check for a faded label, a perished lid, and staining on the shelf below. Never open a bottle with a crusted or seized cap to look inside, since the dust is corrosive to eyes and skin.
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 We do not publish a drain or general waste route for any chemical.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.
The code 16 05 06* usually applies to the solid in a research lab, with 16 05 08* where it is a discarded organic chemical outside a lab pack. Record the bottle as labelled with the approximate weight, the date of opening if known and the cabinet it came from, and keep the stock register up to date until it leaves. The bottle goes into a lab pack with compatible solids, away from acids and oxidising agents. Because it is toxic and corrosive, damaged or leaking bottles should be double contained and flagged to the collector. It must never be washed to a sink or drain, and nobody should try to deactivate it with water or alkali.
| 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: solid.
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
- H301 Toxic if swallowed.
- H314 Causes severe skin burns and eye damage.
Precautionary statements
- P260 Do not breathe dust, fume, gas, mist, vapours or spray.
- 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+P316 IF SWALLOWED: Get emergency medical help immediately.
- 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.
- P321 Specific treatment (see supplemental first aid instruction on this label).
- P330 Rinse mouth.
- P363 Wash contaminated clothing 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
Why do we need a locked cabinet for PMSF?
It carries H301, toxic if swallowed, and H314, severe skin burns and eye damage. A toxic stock needs a locked cabinet with a stock record, kept away from food and drink areas, acids and oxidising agents.
Does an old bottle of PMSF still work?
Not necessarily. PMSF reacts with water, so damp stock can lose its action without looking different. Only competent staff can judge that by use. An undated or damp bottle should be recorded for collection.
Can we get rid of PMSF by reacting it with water first?
No. Deactivating it is not something to attempt at the bench because the stock is corrosive and toxic. Keep it in its bottle, record it and arrange specialist collection.
