Does Hydrogen peroxide expire?
Does Hydrogen peroxide expire?
It decomposes into water. An opened bottle is often plain water within six months.
Unopened: 3 years. Opened: about 6 months
Hydrogen peroxide breaks down into water and oxygen, a reaction accelerated by light, heat, and contact with almost any metal or organic material — which is why it is sold in opaque brown bottles. Every opening introduces contaminants that catalyse it. The test is simple and genuinely works: pour a little into a sink and it should fizz vigorously on contact with the drain. No fizz means water.
How to store it
- Original brown bottle, closed, in the dark.
- Never decant it into a clear container.
How to tell it has gone
- The fizz test. If it does not bubble on skin or in a drain, it has gone.
"Use by" and "best before" are legally different. Use-by is a safety date and should be respected; best-before is about quality, and food is usually fine well past it. Where the two diverge matters, the page above says which applies.
Common questions
- Does Hydrogen peroxide expire?
- It decomposes into water. An opened bottle is often plain water within six months.
- How long does Hydrogen peroxide last?
- Unopened: 3 years. Opened: about 6 months
Related pages
- Does Eggs expire? Eggs stay usable for weeks past the date on the box, and the float test tells you about age rather than safety.
- Does Medicines expire? Most solid medicines keep much of their potency for years past the date — but a handful genuinely must not be used late.
- Does Petrol and diesel expire? Petrol goes stale within months, and ethanol blends go faster because they absorb water.
- Does Batteries expire? They self-discharge on the shelf, at very different rates by chemistry — and alkalines leak when flat.
- Does Wine expire? The great majority of wine is meant to be drunk within a year or two. Very little of it improves.
- Does Chocolate expire? It keeps far longer than the date. The white bloom on old chocolate is fat or sugar, not mould.
- Does Household bleach expire? It loses strength within months and eventually becomes salt water. This surprises most people.
- Does Paint expire? Unopened water-based paint keeps a few years; opened tins depend entirely on how well they were sealed.
- Does Honey expire? Does not expire
- Does Milk expire? Has a real expiry date
- Does Sunscreen expire? Unsafe or ineffective after the date
- Does Salt expire? Does not expire
- Does Frozen food expire? Indefinite if stored properly
- Does Canned food expire? Indefinite if stored properly
Sources
- US Food and Drug Administration — FDA (Public domain (US Government))