Fumigation

Training is available in all aspects of fumigation practice and health and safety:

Fumigation is the use of a toxic gas to control pests.  Vertebrate pests,  e.g.: rabbits and rodents, invertebrate pests, e.g.: moths and beetles, and certain plant diseases, e.g.: some rusts, can be controlled by some fumigants. One of the commonest gases in use for many years within the food industry, methyl bromide, can achieve all three types of pest control.

Because all fumigants are at least as toxic to all animals, (including humans), as to invertebrates, in Europe, fumigation of commodities and buildings can only be carried out by trained and certificated fumigation operators.  However, it is very useful for all involved in the storage of food commodities and working in food manufacturing plants, to understand the principles and practical aspects of fumigation, so that they can consider or recommend fumigation only when it is likely to be the best option.  At the same time, they will appreciate the limitations of this unique pest control technique.

Pesticides in food storage

In food storage, many different types of pesticide are used to prevent and/or control insects and mites.  These include conventional high-volume sprays for use on warehouse walls, dusts for broken floors and wall/floor angles, ultra-low volume sprays for use on sacks and sometimes the structure, aerosols, mists and fogs for treating the air volume in the store against flying insects.  There is no longer a clearance for the use of impregnated plastic strips which contain dichlorvos, slowly releasing it as a vapour into the local air space, which, in any case, was not a fumigation, because the larger dichlorvos molecules could not penetrate through packaging and into commodities.  

Common fumigants and developments

Currently there is only one fumigant in common use against insects and mites in the food industry - phosphine.  Methyl bromide was withdrawn (under the terms of the Montreal Protocol) in 2006, and hydrogen cyanide, was gradually withdrawn about 15 years ago; it’s last main use against insects was for the complete fumigation of flour mills.

Methyl bromide is still available for use in developing countries, and should remain until 2015

Sulfuryl fluoride, hitherto confined to termite and other wood-boring insect control mostly in America, is undergoing trials in Europe to try to gain clearance for some food commodities and currently is only available for whole empty building fumigations, for example, mills and warehouses.

Phosphine (PH3) is the commonest fumigant in use worldwide.  It has been available commercially since the Second World War, originally being produced solely by Germany.  In recent years, India, some South American countries and China have produced their own versions, though usually very similar to the original German formulations.

Phosphine gas is generated on-site by the action of atmospheric moisture on solid aluminium, or magnesium, phosphide preparations, in tablet, pellet, sachet, plate or strip form.

Contact Mike Kelly for further information