2,4-Dinitrophenol (CAS 51-28-5): storage and disposal
2,4-Dinitrophenol is a yellow solid sold damp, found in college and university stores, usually as an old bottle bought for organic or biochemical work. It is fatal if swallowed and toxic through the skin and by inhalation, and repeated exposure can damage organs. Dry material is explosive. The water it was supplied with is therefore what decides how it can be handled, and that can only be judged in person.
- CAS number
- 51-28-5
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code
- 16 05 06*
Acute toxicity
Serious health hazard
Hazardous to the environment
This chemical is a manual enquiry
This can become unstable or explosive, especially if it is old or has dried out. Nobody should move it until someone competent has looked at it, so we start with a conversation and usually a store assessment.
Explosive if dry.
It cannot be priced through a form. Please do not open or move it. Call us or send an enquiry and we will talk through the safe next step, which is often a store assessment.
What to do this week
- Leave it where it is. If it looks old, crystalline or damaged, do not open or move it and keep people away from the shelf.
- Write down the label wording, the rough age and where it is stored, from a safe distance.
- Send us those details, and a photo if you can take one without touching it.
Safe storage in a school or lab
Oxidisers and acids are the first things to keep away from it, since a reaction with either could release toxic vapours from an already very poisonous solid. A locked cabinet with a stock record suits it, clear of food and drink areas. The bigger concern is water loss. It stays stable only while it remains damp, so a warm shelf, a radiator pipe or a lid left slightly loose does slow damage. Stand it where it will not be knocked, and keep it in the original container with the label facing out. Should a bottle ever look dry, it stays exactly where it is and nobody tries to wet it again.
How to tell it has deteriorated
Yellow is what catches the eye first. A yellow stain on the label, the cap or the shelf below means the solid has been getting out of the bottle, and the same stain on a glove or on skin shows contact has already happened. Damp stock looks like a moist yellow solid that clings together. Dried stock looks loose and free running, and may have pulled away from the glass. A yellow crust at the neck or around the closure is a warning too, because that material has dried in the worst possible place. If it is old, undated or shows any of these signs, do not move it, do not open it, and get a specialist assessment.
Supplied damp. Becomes an explosion risk when it dries out.
How it must be disposed of
This does not go through our standard collection route. It is arranged by manual enquiry, and never goes down the drain or into general waste.
It leaves a site only after a manual enquiry and an assessment, since it is not quoted online and sits outside the online quote path. We recommend a store assessment, carried out in person by a competent chemist, and a warning sign may mean an explosives or emergency specialist is needed. Say how much you believe is there, which room it is in, and whether you can see dry contents or a crust from where you stand. Do not lift the bottle to read the back of the label. Being very toxic to aquatic life, it must never reach a drain, and nobody should open it, move it or add water to make it safe.
| 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: damp solid.
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
- H300 Fatal if swallowed.
- H311 Toxic in contact with skin.
- H331 Toxic if inhaled.
- H372 Causes damage to organs through prolonged or repeated exposure.
- H400 Very toxic to aquatic life.
Precautionary statements
- P260 Do not breathe dust, fume, gas, mist, vapours or spray.
- P261 Avoid breathing dust, fume, gas, mist, vapours or spray.
- P262 Do not get in eyes, on skin, or on clothing.
- P264 Wash hands and exposed skin thoroughly after handling.
- P270 Do not eat, drink or smoke when using this product.
- 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.
- P301+P316 IF SWALLOWED: Get emergency medical help immediately.
- P302+P352 IF ON SKIN: Wash with plenty of water.
- P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing.
- P316 Get emergency medical help immediately.
- P319 Get medical help if you feel unwell.
- P321 Specific treatment (see supplemental first aid instruction on this label).
- P330 Rinse mouth.
- P361+P364 Take off immediately all 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
A technician has yellow marks on their fingers after handling an old bottle. Does it matter?
Yes. Yellow skin staining shows contact, and this solid is toxic through the skin. Follow your first aid procedure, seek medical advice and tell your safety lead. Leave the bottle alone, because handling has already shown it is contaminated on the outside.
Can we keep it with other nitro compounds in one locked cupboard?
A locked cupboard is right in principle, but anything old or dry should not be gathered together with other stock, because moving it is the risk. Leave bottles where they are, list each one and ask for the whole group to be assessed in place.
How do we tell whether a brown glass bottle is still damp when we cannot see in?
You often cannot, and opening or tilting it to find out is the wrong move. Treat a bottle you cannot see into as unknown. Note the label, the age and the outside condition, then raise an enquiry and let an assessor judge it.