With the exception of opting for a physical barrier control measure, almost all termite control methods available in Malaysia are relying on pesticides.
A pesticide which is used to control termites is generally referred to as an insecticide or more specifically, a Termiticide.
There are many different brand termiticides used before or being used now in Malaysia. It is always appropriate to refer these termiticides with their active ingredients (AI in short) rather than their brand names as one active ingredient could be registered in many brand names.
Thus, in the following texts, we would mention termiticides by their active ingredients used.
Termite controls in Malaysia in the 70s through the 90s were relying on arsenic compounds and chlordane.
Historically, arsenic compounds have medicinal values. It was used to treat, among others, dietary deficiencies, neuralgia, rheumatism, asthma, tuberculosis, diabetes, fever, skin disorders, malaria and syphilis.
Arsenic was considered the perfect poison for its odorless, tasteless and sugar-like physical appearance. It also causes a slow painful death and difficult to detect in the human body.
A dose of 20 mg arsenic trioxide may be life-threatening while doses ranging from 200 to 300 mg have always been associated with death.
In termite control, arsenic trioxide in powder form has been used to eliminate termite colonies.
Small quantities of arsenic trioxide dust were puffed into active termite mud tubes. The dust sticks to the bodies of the passing termites and is distributed into the colony. Eventually, the poisoned termite queen will be killed and the colony will be eliminated.
Due to its highly toxic and carcinogenic (could cause cancer in human) nature, arsenic trioxide treatment on termites had been banned in most countries in the world including Malaysia.
Chlordane, on the other hand, is a highly persistent termiticide.
It was reported that chlordane could stay in the soil for over 20 years and that is why it is so popular then because it could give that kind of long-termed termite protection.
The negative effect is that chlordane lost from soil through evaporation. It was reported that half of the chlordane applied to the soil may evaporate in 2 to 3 days.
The story did not end there. The applied chlordane is evaporating from the treated soil slowly thereafter for many years. In USA, today there are still people receive the exposure to chlordane from living in homes that were treated with chlordane for termites many years ago.
It is reported that chlordane contaminates the air of over 30 million U.S. homes by diffusion through concrete flooring, ceiling drywall or out-gassing from previously treated indoor areas.
Most health effects in humans that may be linked to chlordane are on the nervous system, the digestive system, and the liver. Documented health problems can include child cancers, leukemia, chronic infection, bronchitis, asthma, sinusitis, infertility, neurological disorders, aggression and depression.
It is due to these series of adverse effects that the use of chlordane for termite control is banned in almost all countries in the world including Malaysia.
The bad experiences with arsenic trioxide and chlordane have definitely made pesticides suppliers to be more careful and cautious in introducing termiticides into the termite control market.
These next generation termiticides being introduced after that were not only effective but also less persistent and less toxic to human beings. However, some of the older termiticides in the market are still having some toxicological problems to human beings.
After the banning of chlordane in 1998, chlorpyrifos had become the main termiticide used by most of the pest control operators.
At its peak, chlorpyrifos had dominated more than 80% of the termiticides used in the Malaysian market. It is also a favorite choice of the operators due to its lower cost as compared to other termiticides.
However, chlorpyrifos was found to be less persistent, only last about 2 years in the soil which is far below the expectation of consumers who are still having good experience with chlordane.
In 2001, chlorpyrifos was banned for household use by the USEPA in the U.S. due to its association with mental and physical impairments in children in low-income areas after exposure to the termiticide.
The ban did not take effect in Malaysia. Although its market share has dropped after some newer termiticides were introduced in Malaysia, chlorpyrifos is still the main insecticide used for termite control as well as other urban pests (ants, cockroaches and others) in the household sector.
The turn of century saw the introduction of a couple of more effective and safer termiticides into the market.
Imidacloprid and Fipronil can effectively control with lower dose rate and give about 5 years termite protection when applied into the soil. However, they are not as widely used as chlorpyrifos due to their higher cost.
During the same time Imidacloprid and Fipronil was introduced, a group of termiticide, the chitin synthesis inhibitor (CSI) was introduced.
This type of termiticide is only used to formulate poison termite bait.
When consumed by termites, it basically stops the termites from changing their skin, a process required by termites to grow. These termiticides kill termites slowly, one of the criteria required to eliminate the whole termite colony.
Because it is target focus (only termite would eat the bait) and only minute quantities are required, it is therefore a safer and environmentally friendlier alternative than those termiticides mentioned before.