An Extensive Guide to the Different Classes of Termiticides (Part I)

Termiticides have long been used to control and kill termites. Over the years, many termiticides have been developed and most of these have been commercialized by its developers. To date, there are twelve (12) classes of termiticides including the notorious Chlorinated Hydrocarbon type which has been banned since 1988. The remaining eleven classes are: (1) botanicals, (2) Chloronicotinyls, (3) Fluoroaliphatic Sulfonamides, (4) Inorganics, (5) Insect Growth Regulators, (6) Microbials, (7) Organophosphates, (8) Phenyl pyrazoles, (9) Pyrroles, (10) Synthetic Pyrethroids and (11) Trifluoromethyl aminohydrazones. The first five classes will be discussed in this article.

1. The Botanicals

Termiticides belonging to the Botanical class are the only termiticides that come from plant extracts; the other ten classes are synthetically produced or are all synthesized in a laboratory. Plants that exhibit termite-repelling characteristics include the chrysanthemum and the tobacco plant.

Contrary to what most people believed, botanical termiticides are not necessarily safer that synthetic ones. For example, the fumes coming from the tobacco plant is more dangerous to human health than most of the synthetic termiticides. This is the reason why no termiticide has been developed using the same plant. However, the chrysanthemum offers a different case. The natural compound called pyrethrum that comes naturally from chrysanthemum is very safe and effective in repelling termites.

While pyrethrum is very harsh to insects, its effects to humans and other mammals are almost negligible. However, no matter how safe and effective pyrethrum is, the main problem with this organic chemical is nature itself. Because it is highly organic it easily breaks down even under normal circumstances, i.e. normal temperature and pressure. Nonetheless, it is in the chemical formula of pyrethrum that chemists were able to synthesize a more stable artificial compound that is currently being used as an effective termiticide. Although the chemically produced "pyrethrum" is not as long-lasting as other chemical termiticides, it is still useful enough to serve as a safe and effective termiticide.

2. Chloronicotinyls

Chloronicotinyls are termiticides that do not directly kill termites. These chemicals are considered as indirect termite repellents (see my separate article about direct and indirect termite repellents entitled "A Complete Guide to the Basics of Termiticides") because they kill termites by disorienting them, thereby making them unable to feed and forage for food.

The active ingredient used in Chloronicotinyls is called imidacloprid which attaches itself into the nerve endings of the termites. Because of the presence of the chemical, termites experience a foreign sensation in their bodies which they find disorienting. Moreover, termites that are exposed to imidacloprid having a concentration lower than that which causes disorientation still becomes weak enough to catch naturally occurring diseases that eventually lead to death.

Chloronicotinyls are same to use because of its very low toxicity level to humans and to other warm-blooded animals. Humans and other mammals do not have as many receptors as termites, limiting the sites wherein imidacloprid can attach to.

3. Fluoroaliphatic Sulfonamides

This termiticide class is mostly termite baits. The active ingredient of all termiticide classified under Fluoroaliphatic Sulfonamides is called sulfluramid. Sulfluramid is a recent termiticide discovery, currently being used by two termiticide companies only (FMC Corporation and Spectracide Corporation). Sulfluramid is a slow-killing termiticide that leads to gradual suppression of the termite colony. These products do not eliminate the termite colony in an instant, although it offers a steady and yet effective way to slowly reduce the termite population inside the colony until it ceases to exist.

4. Inorganics

The most popular inorganic termiticides are called borates. Borates are compounds with an active ingredient called boron. Boron is often dispensed as boric acid, although in some applications, boron is also dispensed as disodium octaborate. In both types of dispersion, boron is applied directly unto the wood surface that is to be used in the construction of a building or a house. Boron penetrates deep into the wood making the wood boron-treated from the surface down into its insides. Because of this, boron has been very effective in killing termites because it poisons termites as they eat the wood materials of the house.

Experts are still divided in theorizing as to how boron kills termites. However, the prevalent theory is that boron kills the microorganisms that live inside the guts of termites. These microorganisms are the ones responsible for breaking down cellulose into carbohydrates on which termites actually feed on. Once these microorganisms are dead, termites will have no way of digesting wood and thus die in the process.

Borates come in three commercial forms: liquid, powder and gel. Both liquid and powder borates are to be mixed with water before applying to any wooden surface. Gel borates are to be injected using a syringe into the wooden material to be treated.

5. Insect Growth Regulators

Most of the termiticides under this class are used for termite baiting. Termiticides used for baiting technologies are designed to affect termites indirectly. The termite workers which are the ones who are most exposed to these termiticides does not necessarily feel the effect of the chemical. However, because of the rest of the members of the colony to depend on the workers for food, they are the ones more affected by the chemical. Insect growth inhibitors are compounds that hinder certain portions of the insects to develop and grow. In the case of termites, since the infected termite workers feed all the larvae in the colony, there is a very high chance of them passing on the chemical to the larvae.

An example of an insect growth inhibitor chemical is the diflubenzuron. This chemical is classified as Chitin Synthesis Inhibitor. Chitin is the external shell of the termites that covers their soft organs inside. Now, because only insects such as termites have chitin, humans and other warm-blooded animals are surely safe from the effects of the chemicals. In the long run, these types of chemicals develop a weak and struggling termite colony that is bound to cease existing.

Read the second installment of this article entitled "An Extensive Guide to the Different Classes of Termiticides (Part II)".

Sincerely,
Michael Rozatoru :)