What is Fumigation?

Fumigation is a specialized pest control method that involves enclosing an area or commodity and introducing a gaseous pesticide (fumigant) to penetrate all spaces and kill pests at all life stages—eggs, larvae, pupae, and adults.

When is Fumigation Best Used?

• Export Controls: Many countries require fumigation of goods to prevent the spread of invasive pests.
• Stored Product Fumigation: Grain silos, food warehouses, and storage containers often require fumigation to protect commodities from insect infestation.
• Industrial Food Manufacturing Plants: To ensure hygienic, pest-free environments in large-scale food production.
• Building Fumigation: For severe infestations of termites, wood-boring insects, or other pests in homes and commercial structures.

Fumigation is ideal when pests are hidden in inaccessible areas or when a comprehensive, whole-structure or whole-commodity treatment is necessary.

ProFume Fumigant Gas (Sulfuryl Fluoride): A Powerful Solution

One of the most effective fumigants used today is ProFume, which contains sulfuryl fluoride gas. This colorless, odorless gas penetrates deeply into wood, soil, and enclosed spaces, making it highly effective against pests in all life stages.

Why Choose ProFume?

• Efficacy: Kills eggs, larvae, pupae, and adult pests, ensuring complete eradication.
• Penetration: Reaches pests hidden in cracks, crevices, and deep within materials.
• Non-Flammable: Safer to handle compared to some other fumigants.
• Residue-Free: Leaves no harmful residues on treated surfaces.

Pests Controlled by Sulfuryl Fluoride

ProFume is effective against a wide range of pests, including:

• Termites (subterranean and drywood)
• Wood-boring beetles and powderpost beetles
• Cockroaches
• Bed bugs
• Stored product pests such as weevils, moths, and beetles
• Rodents (in some applications, combined with other control methods)

Summary

• Pest control is a versatile, targeted approach suitable for many everyday pest problems in homes and businesses.
• Fumigation is a specialized, comprehensive treatment best for severe infestations, stored products, export requirements, and industrial settings.
• ProFume (sulfuryl fluoride) is a highly effective fumigant gas that kills all life stages of pests and is widely used in building and commodity fumigation.

Choosing the right method depends on the pest type, infestation severity, and treatment area. For expert advice and professional fumigation or pest control services, always consult licensed specialists.

The use of Terbufos in South Africa

Despite its extreme toxicity, Terbufos is widely and commonly used in the agricultural sector in South Africa. Its sale and access is highly controlled. It was classified in terms of applicable regulations as a “restricted pesticide” in 2023. Farmworkers are exposed to and vulnerable to the highly toxic pesticide as it is often used without the necessary protective gear.

In the townships, informal settlements and at taxi ranks, it is known as “halephirimi”. Translated to mean ‘you will never see the sunset’, halephirimi lives up to its promise and guarantee. It is highly toxic, lethal and fast acting. At any street corner in townships and informal settlements, one can easily find the small black bag of granulated poison. It is almost always in the translucent, unmarked, small packet used for packaging ‘amakipkip’ and other snacks loved by children. It has three main uses in townships: suicide, dogs and rats.

The Gauteng health department reports that halephirimi is a popular choice for those attempting suicide, particularly in the townships. Criminals, such as burglars, rub halephirimi on pieces of meat to quickly kill guard dogs. But its most common use is to kill rats which have become an endemic problem in townships. Poor waste management in several municipalities has propegated this issue. Rubbish is not collected, streets are not cleaned and rodent infestations thrive in such conditions.

Government Responses

Delivering government’s comprehensive response to the reported cases last November,Ramaphosa presented Cabinet’s decision of a three-pronged intervention strategy:

1. Get hazardous pesticides off the street
2. Protect children from exposure
3. Prevent future outbreaks.

Last December, the African Centre for Biodiversity and a coalition of farm workers and civil society organisations petitioned Agriculture Minister John Steenhuisen and the registrar, in terms of Act 36 of 1947, “ to ban the acquisition, disposal, sale, or use in any form of the registered agricultural remedy known as Terbufos”.

In his response, Steenhuisen said: “It’s very easy for these organisations to stand on a soapbox and say,’immediately ban it’ … [but there are] broader implications for the agricultural sector, not least around food security.” T

The minister also cautioned against possible huge crop failures, pest infestations and food insecurity if the pesticide is banned without appropriate alternatives.

Can we replace deadly pesticides such as Terbufos in South Africa?

The efficacy of sulfuryl fluoride (ProFume Fumigant Gas) is well established for use in enclosed areas such as grain silos, wooden structures and containers for export. Its use in postharvest stores and distribution chains is inequivicable.

A German patent application from Bayer CropScience AG in 2003 looked at sulfuryl fluoride to be used as a soil fumigant for disinfecting soil or as a product for controlling soil-borne, plant-damaging nematodes, insects, fungi and bacteria and for controlling unwanted plant growth. Their mechanisms of treatment included injecting into the ground using stationary or mobile devices. The soil was mechanically compacted or covered during and after treatment. They also experimented with injecting the compound under a film covering the ground or by drenching the ground.

Sulfuryl fluoride was found to be surprisingly highly effective against plant pathogens. Nematodes could also be controlled including the ‘ice stage’ where the eggs remain dormant but viable under winter snows (Europe) or frost. As with other pests, the complete life cycle is addressed using sulfuryl fluoride.

Certain regions in China find the use of Sulfuryl Fluoride as a soil fumigant against root-knot nematodes and other key soil pathogens to be an economically viable alternative to methyl bromide use in similar applications.

Although the mechanism of action of SF means it is effective against rodents in confined areas such as warehouses and food stores, using it to combat the endemic problem of rat infestations in urban and township areas is not possible. Rat control requires a comprehensive management plan involving strict adherance to municipal waste management protocols.

Can Sulfuryl Fluoride replace Terbufos in the Agricultural Sector?

The results are promising that, like other countries in Africa, Terbufos can and should be banned as quickly as possible in South Africa to avoid tragic deaths. However, finding complete and viable solutions to replace its use in the agricultural sector will require additional governmental controls and legislation. Labelling SF for use in the agricultural space requires registration for such in the annals of government, and that, unfortunately, is an expensive and time consuming undertaking.

Specialized fumigation companies.

Many pest control companies specialise in a particular aspect of fumigation such as:

• Woodborer treatments in historical buildings or museums containing artefacts.
• Fumigation services for businesses in logistics and shipping including ISPM 15 certification for cargo and commodities for export.
• Fumigation for residential homes or business buildings.
• Grain silos and other storage facilities.

Other fumigation considerations

The price of fumigation depends on the volume of goods, preparation needed and the gas used. Sulfuryl fluoride fumigant gas is more expensive than its predessesor  methyl bromide, for example, but less volume is needed for structural fumigations. This equates to a 60% saving for the client.

Certain pests may have built resistance to a particular fumigant, so an alternate works best. Phosphine resistance has been combatted with the advent of sulfuryl fluoride fumigant gas.

It is important to remove certain items before fumigation such as unsealed food, medication, plants and, of course, all animals including fish in tanks.

Uses of Sulfuryl Fluoride

Sulfuryl fluoride is introduced into structures as a gas which fills all air spaces in the enclosed area and penetrate cracks, crevices and pores in the wood. The gas penetrates materials quickly and rapidly but dissipates during the ventilation process. It has been widely used as a fumigant to kill both the eggs and adults of insects such as cockroaches, termites, beetles, moths and flies after exposure of 16–22 hours with a concentration range from 0.5 to 3.5 and 5–77 g m−3 for LD95 for adults and eggs, respectively. Sufuryl fluoride is also used (successfully) on postembryonic forms of fleas, rodents, ants, bees, wasps, spiders, millipedes, bedbugs, silverfish, springtails, earwigs, fire- brats, book lice, and brown dog ticks.

It is crucial to contain sulfuryl fluoride for a sufficient period of time so tenting is used around the structure during fumigation. Any opening is sealed (door frames, window frames, key locks or drainage pipes for example) using a specialized ‘Pink Tape‘. Traditional masking tapes or duct tape are too porous to contain sulfuryl fluoride molecules.

Mechanism of action of sulfuryl fluoride on pest infestations

Sulfuryl fluoride has a complex mode of action. It is thought to be toxic primarily through the action of the fluoride ion which it contains. It inhibits oxygen uptake, disturbs the normal phosphate balance, and inhibits hydrolysis (breakdown) of fatty acids. The fluoride ion in sulfuryl fluoride is thought to bind to calcium (leading to spasms and seizures) as well as potassium and magnesium. Enzymes which require a magnesium ion for their normal function are inhibited by sulfuryl fluoride; these enzymes include enolases (used to metabolize sugar) and ATPase, an enzyme that is important in cellular energy metabolism. The end result is that sulfuryl fluoride prevents stored fats from being utilized, and there is insufficient energy for survival.

You can read more about the chemical action and interactions of sulfuryl fluoride here:  Fact Sheet from the Journal of Pesticide Reform

Toxicity management of sulfuryl fluoride

Sulfuryl fluoride is “an extremely hazardous gas.” The most straightforward demonstration of its acute toxicity are the classifications and  restrictions placed on itsuse by the U.S. Environmental Protection Agency (EPA). EPA classifies sulfuryl fluoride as a restricted use pesticide. This means that the pesticide must be used by or under the supervision of a certified applicator who is wearing protective clothing. Sulfuryl fluoride is also labeled with the signal word “Danger” by EPA, meaning that it is in the most acutely  toxic category of pesticides. Because of sulfuryl fluoride’s acute toxicity, all entrances to the fumigated areas must be posted with a skull and crossbones sign. No one is permitted in the treated area without self-contained breathing apparatus until it has been thoroughly ventilated according to approved procedures and concentrations of sulfuryl fluoride have been measured at less than 5 parts per million.

Efficacy of sulfuryl fluoride in South Africa

Since implementing sulfuryl fluoride in South Africa, we have had a 100% success rate in treating all life stages of pest and has even proven effective against phosphine resistant pests. We estimate over 60% of all fumigations are now undertaken with sulfuryl fluoride. Structural fumigation using sulfuryl fluoride is most cost effective as the quantity of gas required is significantly reduced. Read more When Pesticides No Longer Work

A global search for alternate fumigants for export markets

As methyl bromide is phased out globally, alternatives such as phosphine (PH3), ethyl formate (EF) used in quarantine procedures and ethanedinitrile (EDN) have been introduced in various global markets. Each alternative has distinct disadvantages though:

• EF has a high sorption rate and lower permeability because of its lower vapor pressure compared with other fumigants
• Phospine requires a longer fumigation time than MB or EDN and certain pests have become resistant to it.
• EDN is expensive, costing more than twice that of MB, without a significant difference in the treatment efficacy or convenience of use

ProFume Sulfuryl fluoride, however, has shown tangible efficacy in controlled studies such as this one:

Sulfuryl Fluoride Fumigation as a Quarantine Treatment for the Control of Reticulitermes speratus Kolbe (Blattodea: Rhinotermitidae) in Wood

The future of sulfuryl fluoride in South Africa

Aligned to the global trend to find more environmentally friendly fumigants, sulfuryl fluoride shows robust promise to replace methyl bromide for all structural fumigations and most postharvest pest management and ISPM15 export requirements.

To date, the efficacy of sulfuryl fluoride is 100% against all life stages of pest. Since it is effective against phosphine resistant pests, its use is warranted in postharvest applications where phosphine may have dominated a decade ago.

Structural fumigation with sulfuryl fluoride is definitively more cost effective than methyl bromide due to its sorption and penetration results. Postharvest use of sulfuryl fluoride is more expensive than methyl bromide, but its effectiveness offers a degree of quality assurance beyond MB.

As more global markets test and accept sulfuryl fluoride results in ISPM15 commodities, the use of sulfuryl fluoride in export markets will exponentially rise.

Within the food manufacturing industry where senstive electrical equipment forms part of automated manufacturing processes, sulfuryl fluoride is essential. Not only is it able to penetrate into the deep recesses of machinary, it does no damage to electrical components and will not effect the taste, colour or aroma of the product.

The use of sulfuryl fluoride is set to increase globally and in South Africa in the forseeable future.

Signs of woodborer that you may need to fumigate your property

• Look for small, round exit holes (typically 1-2 mm in diameter) on the surface of the wood. These holes are often surrounded by fine wood dust or frass.
• Pay attention to any signs of weakened or crumbling wood, especially if it appears honeycombed or has a powdery texture.
• If you notice adult beetles emerging from the wood or find their discarded wings nearby, it’s a clear indication of an infestation.
• Regular inspections, especially in areas prone to woodborer activity, can help you detect and address the issue early. This will minimize potential damage. Read more Signs of a Woodborer Infestation and What you can do About It

Stored Product Pests

Food products are prone to insect infestations such as beetles, moths, mites, and weevils. Controlling stored product pests is challenging as the entire life cycle of the pest (egg, larva/ nymph, pupa and adult) must be addressed. The eggs are resistant to chemical action. The eggs could hatch a few days or weeks after treatment and the client is faced with a continued pest issue. Sulfuryl Fluoride (ProFume Fumigant Gas) has proved 100% effective through all life stages of pest.

Stored product for animal or human consumption can have no remaining toxic residues. Fumigant gases such as ProFume SUFFOCATE the pest on site and the gas dissipates rapidly thereafter.

Signs of Stored Product Pest Infestation

• Small holes, tears and other damage to packaging
• Dust and spillage outside of storage packaging or containers
• Webbing or larvae found on the outside of bags, bins, boxes or packets
• Larvae, pupae or webbing found on sills, shelving, machinery, beams, on or near storage and in and around spillage
• Pests crawling over counters and floors
• Insects found in other pest traps, such as rodent or fly traps
• Insects found inside stored food items
• WARMTH. Elevated grain temperature indicates pest infestation.
• SOUNDS. Ultrasound devices can be used to detect pests within a grain store.

Container fumigation for infested wooden furniture, artefacts and textiles

Export regulations (ISPM15) require container fumigation of goods that may harbor pests. The brown marmorated stink bug, for example, would decimate a country’s fruit and vegetable crops if introduced to an area without natural predators to oppose the pest. Similarly, wooden logs shipped with woodborer beetles pose a risk to the destination port.

Deep-seated infestation in machinery on your premises

Food manufacturers usually run operations 24/7 and any shut-down has costly consequences. ProFume Fumigant Gas has proved an effective treatment within the industry. Since the gas is non-corrosive, fast acting and targets ALL life stages of pest, ProFume is ideal to target the hard to reach areas within the machinary and factory shut-down is minimized.