MBR or ALP: choosing a fumigant for stored commodity
The two fumigants used for cargo and stored produce in India, how they differ in practice, and what a licensed operation looks like from the client's side.
Fumigation is not spraying with a bigger machine. A fumigant is a gas: it fills the whole enclosed volume and reaches into the commodity itself, which is why it is the only real answer for a container of grain, a stack of timber or a consignment of textiles. Nothing applied to a surface does that.
It is also why fumigation is a separately licensed activity, carried out by an accredited operator rather than by whoever is on the round that day.
The two you will be offered
Methyl bromide (MBR)
Fast, penetrating, and the one most often specified for quarantine and pre-shipment treatment where an importing country requires a recognised certificate. Exposure periods are short — typically measured in hours rather than days — which matters when a container is sitting on a schedule.
It is tightly controlled. Its use is restricted internationally, quarantine and pre-shipment being the significant remaining category, and it requires an accredited operator with a current accreditation number. If a treatment certificate is going to travel with your cargo, this is usually the route.
Aluminium phosphide (ALP)
Supplied as tablets or pouches which release phosphine gas on contact with atmospheric moisture. Slower — exposure is normally measured in days, and temperature has a strong effect on how the gas develops — but widely used for stored grain and long-cycle commodity where the time is available.
The slower release is not only a drawback: a longer exposure at lower concentration deals better with eggs and pupae that a short treatment can leave behind.
How to choose, in practice
- Is a certificate required by the destination? That usually decides it before anything else does.
- How long can the consignment stand still? Hours points one way, days the other.
- What is the commodity? Some absorb bromide; some are stored in conditions where phosphine develops too slowly to be reliable.
- What is the ambient temperature? Cold materially slows ALP.
- Can the space be sealed? Both need a gas-tight enclosure. A sheet thrown over a stack in a draughty shed is not a fumigation.
What a licensed job looks like from your side
Whichever fumigant is used, you should see all of this:
- the operator's accreditation number, and the operator's name on it
- the commodity, quantity and location recorded before work starts
- the dosage and the planned exposure period, stated in advance
- sealing checked, and the area placarded and secured
- a stated aeration period, and a clearance reading before re-entry
- a certificate carrying all of the above
The clearance reading is the one to insist on. Aeration is where the risk sits for your staff, and "it has been open a while" is not a measurement.
A note on the alternative
Fumigation is also a barrier at a national scale — it is a large part of how a country stops a foreign pest arriving in a shipment and establishing itself. That is worth remembering when a treatment looks like an administrative cost on a shipping document. It is doing something, and the something is not only about your consignment.
Written for facility managers and QA heads. If something here does not match what your auditor is asking for, call us on and we will go through it — whether or not you are a client.