Lead(II) oxide (CAS 1317-36-8): storage and disposal
Lead(II) oxide, often labelled litharge, is a heavy yellow to orange-red powder that survives in school, college and university stores as legacy stock. It is classified as suspected of causing cancer, as able to damage the unborn child, as suspected of damaging fertility, and as able to cause organ damage through repeated exposure. It is also very toxic to aquatic life. Old jars of it are rarely used and easily forgotten.
- CAS number
- 1317-36-8
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code, laboratory stock
- 16 05 06*
Harmful or irritant
Serious health hazard
Hazardous to the environment
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 powder that is harmful by inhalation belongs in a locked cupboard with a stock record, in a tightly closed jar standing in a tray so spilt powder is contained. Keep it clear of acids, since the oxide dissolves in them to give soluble lead salts, and clear of oxidisers, because toxic and oxidising stock are stored apart. Legacy jars often have a cracked plastic lid or a glass stopper that has seized, so check that the closure still seals before the jar is moved at all. Fine powder on the outside of the jar or in the tray means handling has already spread it. Name, date and quantity belong on the label and in the register.
How to tell it has deteriorated
Litharge is a stable oxide, so there is no dramatic ageing. What does happen is slow uptake of carbon dioxide from the air, which gives the surface a paler, crusty carbonate layer, and a jar that has been open a lot may show a lumpy top and powder caked around the neck. Seized stoppers, split caps and powder dust on the shelf are the signs that matter most to the person handling it. A faded or missing label on an unmarked yellow-orange powder should be treated as an unidentified lead stock. Check for stock-record gaps, because many such jars have outlived the technician who bought them.
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 We do not publish a drain or general waste route for any chemical.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.
Treat a legacy jar of litharge as a job for a person with the right protection, not as something to tidy away. Record the jar's size, its label, the state of its closure and whether powder has escaped, since a dusty container is more awkward to collect than a clean one. Never sweep the powder into a bin, dissolve it or wash it away. It is normally a hazardous waste under 16 05 06* in a laboratory pack or 16 05 07* when discarded inorganic stock sits outside a lab pack, though the producer classifies the waste. The jar is packed away from acids and oxidisers in a compatible group and is collected by a specialist.
| Usual EWC code, laboratory stock | 16 05 06* |
|---|---|
| Discarded inorganic chemical, not a laboratory pack | 16 05 07* |
| 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: litharge, legacy stock.
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.
- H332 Harmful if inhaled.
- H351 Suspected of causing cancer.
- H360Df May damage the unborn child. Suspected of damaging fertility.
- H373 May cause damage to organs through prolonged or repeated exposure.
- H410 Very toxic to aquatic life with long lasting effects.
Precautionary statements
- P203 Obtain, read and follow all safety instructions before use.
- P260 Do not breathe dust, fume, gas, mist, vapours or spray.
- P261 Avoid breathing dust, fume, gas, mist, vapours or spray.
- P263 Avoid contact during pregnancy and while nursing.
- 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+P317 IF SWALLOWED: Get medical help.
- P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing.
- P317 Get medical help.
- P318 If exposed or concerned, get medical advice.
- P319 Get medical help if you feel unwell.
- P330 Rinse mouth.
- P391 Collect spillage.
- 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
We found an old jar of yellow powder marked litharge. Is it lead oxide?
Litharge is a name for lead(II) oxide, but do not rely on colour alone. Keep the jar closed in a tray, record the label and send an enquiry so the contents can be confirmed and described.
What makes it more serious than ordinary salts?
It is classified as suspected of causing cancer, as able to damage the unborn child, as suspected of damaging fertility, and as able to cause organ damage through repeated exposure. The fine powder can also be harmful if inhaled.
Is dust around the jar a reason to act?
Yes. Do not wipe or sweep it dry. Record it, keep people away from the area, and arrange specialist collection, mentioning the loose powder when you ask.
Does the powder change as it ages?
Slowly, if at all. A paler crust can form as it takes carbon dioxide from the air, but the main concern is the container, its seal and its label.
