Lead(II) acetate (CAS 301-04-2): storage and disposal
School chemistry cupboards often hold lead(II) acetate as the trihydrate crystal and as lead acetate paper, kept for detecting sulfide gases. It is a soluble lead salt classified as able to damage fertility and the unborn child, as causing damage to organs through prolonged exposure and as very toxic to aquatic life. It has a sweet taste, which is the reason secure storage matters.
- CAS number
- 301-04-2
- Form
- Solid
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code
- 16 05 06*
Serious health hazard
Hazardous to the environment
What to do this week
- 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 the items listed under "Do not store with".
- If you no longer need it, add it to your disposal list so it goes on the next collection.
Safe storage in a school or lab
Start with the lock. A salt with a sweet taste should never sit on an open prep-room shelf where a student could reach it, so keep the trihydrate in a locked toxic-stock cupboard with an entry in the stock record. Lead acetate paper belongs in the same cupboard, in its own sealed pack, not loose in a drawer with litmus and other test papers. Keep both away from incompatible oxidising chemicals and follow the supplier safety data sheet for segregation from acids and other substances. Put the date on every container on arrival, and do not leave an old tin of paper at the back of a technician's drawer.
How to tell it has deteriorated
The trihydrate can give a faint vinegar smell as it ages, and the crystals may lose their clear look and develop a white powdery coating, since the salt reacts slowly with carbon dioxide in air. Lumps, a crust at the neck and a cap that sticks are the practical signs. Lead acetate paper that has gone grey or brown in the pack has already met hydrogen sulfide or damp air and is spent, while paper that has become brittle, curled or stained shows the packet has not been sealed. Faded labels and a missing stock record count as deterioration too, because nobody then knows how old it is.
How it must be disposed of
By specialist collection only. It never goes down the drain or into general waste. It is normally packed in a toxic laboratory pack with compatible chemicals.
Unused indicator paper contains lead acetate, while used paper exposed to sulfide may also contain lead sulfide. Describe the crystals and indicator papers separately as lead-containing chemical waste, identifying used papers where known, so the specialist collector can assess their contents and suitable packing. The row also has a code for discarded organic chemical outside a laboratory pack, 16 05 08*, alongside 16 05 06* for the lab pack route, so say how the stock is presented. It does not go down a drain, into the bin or into any treatment, and nobody should try to burn the paper. UN 1616 is the transport entry. The collection is a specialist one, with the stock packed away from acids in a compatible group.
| 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: trihydrate, lead acetate paper.
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
- 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.
- P273 Avoid release to the environment.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P318 If exposed or concerned, get medical advice.
- P319 Get medical help if you feel unwell.
- 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
Do used lead acetate papers count as waste for collection?
Yes. The paper carries lead acetate, which is classified for reproductive harm and as very toxic to aquatic life. Keep used and unused papers sealed and labelled, and include them in the collection request.
Why does the lock matter if it is only a few crystals?
Lead acetate has a sweet taste, which makes accidental swallowing a real risk, and it is classified as able to damage fertility and the unborn child. Keep it in a locked cupboard with a stock record.
Which waste code do we use?
A laboratory pack uses 16 05 06*. Stock discarded outside a laboratory pack as an organic chemical uses 16 05 08*. Describe how it will be presented and let the collector confirm the match.
Our crystals smell faintly of vinegar. Is that a problem?
It suggests the trihydrate has started to break down, so the stock is ageing. Do not sniff to investigate. Keep the cap tight, record it and arrange collection.
