Lead(II) iodide (CAS 10101-63-0): storage and disposal
Lead(II) iodide is the bright yellow solid behind the classic precipitation demonstration, and school, college and university stores keep a bottle of it long after the lesson. It is classified as harmful if swallowed or inhaled, as able to damage the unborn child and suspected of damaging fertility, as able to cause organ damage through repeated exposure and as very toxic to aquatic life. The cheerful colour makes it easy to underestimate.
- CAS number
- 10101-63-0
- 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
Keep it apart from incompatible oxidising chemicals, which can react with iodide, and follow the supplier safety data sheet for other storage segregation requirements. A locked cupboard and a stock record suit it better than an open prep-room shelf, and the jar should stand in its own tray so powder cannot spread. Because the bright yellow powder looks inviting to a student, do not leave a demonstration sample on a bench or in an unlabelled tube. Put the date and quantity on the label. If a jar is kept in the room where the lesson takes place, move it back to the cupboard at the end of the day.
How to tell it has deteriorated
Look at the colour. Fresh lead iodide is a vivid, even yellow, and a jar that has stood in light can dull or take on a brownish tinge as iodine is slowly liberated, so a faded or patchy powder has been on the shelf too long or too near a window. Clumping, damp caking and powder stuck round the thread suggest the cap is not sealing. Brown staining on the cap or the tray beneath is worth recording. A label that has gone pale or a stock record that has no entry for the jar are signs of ageing too, and they matter as much as the powder's colour.
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 We do not publish a drain or general waste route for any chemical.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.
Write down the container size, the label as it reads, the colour of the contents and whether the cap seals, then keep the jar in its tray until the carrier arrives. Anything made up from it in a lesson, such as a filtered yellow solid or a tube of residue, should be bottled and labelled as lead iodide waste and not left in a beaker. Never put any of it into a drain or a bin, and nobody should try to dissolve the solid to clear a stained jar. The usual code is 16 05 06* in a laboratory pack and 16 05 07* for stock outside one, though the producer classifies the waste.
| 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: 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
- H302 Harmful if swallowed.
- H332 Harmful if inhaled.
- 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.
- 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
Can the yellow precipitate from a practical be binned?
No. It is lead iodide, classified as very toxic to aquatic life and as able to damage the unborn child and suspected of damaging fertility. Collect it in a labelled container and include it in the collection request.
Why has our lead iodide gone brownish?
Light and air can slowly free iodine from it, which dulls the yellow. The stock is still hazardous waste. Note the change on the record and keep the cap closed and the jar in a tray.
Which store should it go in?
A locked cupboard with a stock record, away from acids and oxidisers. A general salts shelf is not suitable for a lead compound with reproductive and organ hazards.
How do we describe leftover lesson residue?
As lead iodide waste, in a sealed, labelled container, separate from the original stock. Give the approximate amount and say that it came from a practical, so it is grouped correctly.
