What is the only approved formulation for in-transit fumigation?

The only approved formulation for in-transit fumigation is aluminum phosphide. This material is widely used in situations where commodities are being transported, particularly in sealed containers. Aluminum phosphide releases phosphine gas upon contact with moisture and is effective against a range of pests while being safe for use when handled according to regulations.

The effectiveness of aluminum phosphide in in-transit fumigation is due to its ability to penetrate cargo and provide a consistent concentration of the fumigant throughout the treated area. It is essential for maintaining the safety and legality of maintaining pest-free conditions during transport.

Other formulations, like chloropicrin and methyl bromide, have specific uses and restrictions that limit their application. For example, methyl bromide is being phased out under international agreements due to its ozone-depleting properties. While phosphine gas itself is indeed a critical component of aluminum phosphide, the standalone gas is not used direct in fumigation applications. This makes aluminum phosphide the suitable and approved choice for in-transit fumigation scenarios.