Podophyllotoxin (CAS 518-28-5): storage and disposal
Podophyllotoxin is the plant-derived active in topical wart solution, held by sexual health clinics and pharmacies in small bottles, often with applicators. As a substance it is toxic if swallowed, fatal in contact with skin, and irritates skin, eyes and airways. The dilute solution may be less hazardous than that, though the skin route is still what staff should keep in mind. Part-used bottles, poor closure and uncertain age tend to decide how it is handled.
- CAS number
- 518-28-5
- Form
- Solution
- Storage class
- Toxic
- Signal word
- Danger
- Usual EWC code
- 16 05 06*
Acute toxicity
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
Small glass or plastic bottles with a tight cap and applicators are the normal presentation, usually inside a carton with a patient leaflet. Those bottles are easy to lose in a clinic drawer, and a leaking one is a skin contact problem for the next hand that reaches in. Keep them upright, boxed and in a locked cabinet with a stock record, separate from creams and other topical products that staff handle without gloves. Light can affect the contents, so the carton is worth keeping. Used applicators and swabs should not be left with the bottle. Acids and oxidisers belong in another store, since reactions with them could release toxic vapours.
How to tell it has deteriorated
Ageing here is mostly a matter of the solvent escaping. The solution is usually alcohol based, so a bottle with a tired closure loses volume over time, and what remains may be stronger than the label says. A low level in a bottle nobody remembers using, or a sticky residue around the neck, is therefore a real warning and not merely untidy. Darkening or solids in what should be a clear liquid are also a concern. Check whether the outer carton and label are stained, since a stained carton often means an earlier leak. Otherwise the solution gives few visual signs. Do not unscrew a cap to check, and do not top up or mix bottles.
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.
Rinsing a part-used bottle into a sink is never acceptable, and neither is dropping it into a clinical bag with used swabs. Specialist collection is the only route, and the item can normally be included through the online quote path as long as it is accurately described. In a clinic or hospital pharmacy, 18 01 08* is the code that usually fits this type of medicine. Note the number of bottles, how full each looks and whether any have leaked, because a sticky or stained bottle needs extra containment. Applicators that came with the product should be mentioned separately. If the cap has failed, leave the bottle upright in its secondary container and say so.
| EWC code, laboratory chemicals | 16 05 06* |
|---|---|
| Discarded organic chemical, not a laboratory pack | 16 05 08* |
| Human healthcare setting | 18 01 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: topical solution.
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
- H301 Toxic if swallowed.
- H310 Fatal in contact with skin.
- H315 Causes skin irritation.
- H319 Causes serious eye irritation.
- H335 May cause respiratory irritation.
Precautionary statements
- 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.
- P264+P265 Wash hands and exposed skin thoroughly after handling. Do not touch eyes.
- P270 Do not eat, drink or smoke when using this product.
- P271 Use only outdoors or in a well-ventilated area.
- 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.
- P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
- 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.
- P332+P317 If skin irritation occurs: Get medical help.
- P337+P317 If eye irritation persists: Get medical help.
- P361+P364 Take off immediately all contaminated clothing. And wash it before reuse.
- P362+P364 Take off contaminated clothing. And wash it before reuse.
- 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
Why does it matter that a podophyllotoxin bottle has lost volume?
A lower level usually means solvent has evaporated, which can leave the remaining liquid more concentrated than the label suggests. Stating this helps the collector describe and pack it properly. Leave the cap alone, keep the bottle upright, and note its approximate level and any residue around the neck.
Should used applicators go with the leftover solution?
Do not put them loose in the same box. Ask your clinical waste lead how contaminated applicators are handled on your site, because anything used on a patient is a separate waste stream. Unused applicators sealed in the original carton can stay with the bottle and be listed on the same line.
We found a bottle with no carton. Can it stay with the other topical stock?
Better not. Without its carton the warning information may be lost, and staff may reach for it thinking it is a routine topical product. Put a clear label near it through your local procedure, keep it in a locked place and record it until the collection is arranged.
