Cresol mixed isomers (CAS 1319-77-3): storage and disposal
Cresol mixed isomers usually means an old bottle of cresol based disinfectant, found at the back of a college prep room, in a clinic cupboard or in a veterinary practice store. The liquid is toxic if swallowed or in contact with skin and causes severe skin burns and eye damage. Because it was once routine cleaning stock, the temptation to use it up is the main risk with it now.
- CAS number
- 1319-77-3
- Form
- Liquid
- 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
At the back of a college prep room or technician's store, old cresol disinfectant often sits at floor level among cleaning products, which is the wrong company for a toxic corrosive liquid. It belongs in a locked cabinet with a stock record, away from food and drink areas, acids and oxidisers, with the bottle upright in a tray. In a clinic or veterinary practice, old cresol disinfectant should be identified as chemical stock rather than a preparation ready for use. If its identity, container condition or seal is uncertain, leave it undisturbed and arrange specialist assessment before any relocation. A tight cap keeps the phenolic smell inside.
How to tell it has deteriorated
A technician usually notices the smell first, a strong phenolic odour in the cupboard. Then the liquid: it often darkens to yellow or brown with age and air, and the bottle may have a crusted, sticky neck where drips have dried. Old disinfectant bottles tend to have lost labels or been relabelled by hand, and the original product name may be the only record of what is in them. Sound stock is a labelled bottle with a clean neck and a level that matches the record. Anything darkened, leaking or unlabelled is recorded as it stands, left closed and kept upright in a tray.
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 We do not publish a drain or general waste route for any chemical.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.
Old stock must not be used up as a cleaner, diluted for washing down surfaces or poured away to free up the cupboard. It is toxic and causes severe burns, however old the bottle is. Collection is by specialist carrier, packed in a lab pack, usually under 16 05 06*, or under 16 05 08* as a discarded organic chemical outside one. A clinic usually uses 18 01 06* and a veterinary practice 18 02 05*. The producer confirms the classification. Write down the label wording, the container size and any darkening or leak so the packer can plan.
| Usual EWC code, laboratory stock | 16 05 06* |
|---|---|
| Discarded organic chemical, not a laboratory pack | 16 05 08* |
| Human healthcare setting | 18 01 06* |
| Veterinary setting | 18 02 05* |
| 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: legacy disinfectant.
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.
- H311 Toxic in contact with skin.
- H314 Causes severe skin burns and eye damage.
Substance as classified, dilutions may differ.
Questions
Can we use up the old cresol disinfectant on kennel or floor cleaning?
No. It is toxic in contact with skin and causes severe burns, and using it up means handling and spreading it. Keep it closed and labelled as chemical stock and arrange specialist collection.
The bottle label has gone and we only know it was a disinfectant. What now?
Record it as unknown, and pass on whatever history you have, including that it was a disinfectant. Leave it closed and upright in a tray. The collection team can describe it honestly from what you give.
Which waste code applies in a veterinary practice?
A veterinary setting usually uses 18 02 05*, whereas a clinic in human healthcare usually uses 18 01 06* and a college store 16 05 06* in a lab pack. The producer confirms the classification. Say where the bottle has been held when booking.
Does an old bottle become less hazardous with age?
Do not assume so. It carries the same hazard statements, and a darkened or crusted bottle is more likely to leak. Treat age as a reason to book collection sooner.
