Indoxacarb is a newer pesticide most effective at controlling pests that feed upon it such as ants, cockroaches, fleas, and termites.
Pests including ants, carpenter bees, cockroaches, fleas, house flies, fruit flies, stable flies, beetles, boxelder bugs, carpet moths, centipedes, crickets, earwigs, grasshoppers, kudzu bugs, millipedes, pillbugs, roaches, silverfish, sowbugs, stink bugs, dry wood termites, wasps and more.
- Using gel or granuale baits to control ants, termites, and roaches.
- Applying on your pets to control fleas and ticks.
Gel baits, granules, topical applicators (for pets), powder mixes for sprays.
Indoxacarb is the only registered oxadiazine insecticide, though it functions much like pyrethroid insecticides by blocking sodium channels in insect neurons. Unlike many of the pyrethroid insecticides, indoxacarb is more effective when it has been metabolized – making it an effective defense against insects that feed on treated crops or bait packs.
Indoxacarb has been shown to be highly effective against most of the major agricultural pests, and it has recently been adapted into flea, ant, and roach products. Against agricultural pests, indoxacarb is typically applied as a spray. This distributes the chemical over the leaves, where it is consumed by plant-eating insects.
When used as a flea, ant, or roach products, indoxacarb is placed where the creatures will eat it – killing them shortly after.
In spite of indoxacarb’s effectiveness against a wide variety of pest insects, it remains restricted in many countries due to it’s high toxicity to off-target insects, aquatic wildlife, and potential long-term effects to small mammals that inhabit treated fields.
Further, the carcinogen status of indoxacarb has not been properly evaluated and the environmental effects of the chemical also need further study.
For the home consumer, indoxacarb is primarily available for use against fleas, ants, termites, and cockroaches. Since it needs to be eaten to be most effective, indoxacarb is not used for ticks because even a single tick bite on a human can spread disease.
Fleas, ants, termites, and cockroaches baits lead to a 100% death rate with most formulas.
When Was Indoxacarb Created?
Specifically, indoxacarb is an off-balanced mixture of chiral (left- and right-handed) molecules. While DPX-JW062 contains 50%S:50%R enantiomers, indoxacarb contains 75%S:25%R enantiomers – since the S enantiomer is much more effective.
Indoxacarb was patented by the agribusiness giant, DuPont, and is now used in a wide variety of agricultural and residential products ranging from crop protection to flea control.
The original patent claims insecticidal action against many different types of insects – including moths, beetles, butterflies, ants, flies, and most classes of pest insect. Today, indoxacarb is used mostly in commercial agricultural applications, though it is slowly expanding into specific home applications such as cockroach baits.
What is Indoxacarb?
In its pure, dry form, indoxacarb is a white powder. Commercially, the product is mostly sold as a soluble concentrate or granular formula, which is diluted greatly before use. Residential products – including flea treatments and bait products – are pre-diluted to low levels and should be perfectly safe to handle if you follow the manufacturer’s instructions.
The first residential approvals of indoxacarb came after 2003 when several products were approved as ant, roach, and termite baits. These baits seem to be very effective due to the horizontal transfer of the chemical between insects, as well as the fact that social insects share a common source of collected food.
These applications typically use indoxacarb in a gel or paste formula, which worker insects feed on and carry back to the colony to share. Though it can take some time, this usually wipes out entire colonies of ants and termites.
Indoxacarb is an oxadiazine insecticide. Studies have shown that oxadiazine insecticides do not seem to affect the egg stages of most organisms. Oxadiazine has been shown to be effective only when it is ingested by insects – part of the reason it is effective against many species of caterpillar, grub, ant, and termite.
While indoxacarb is acutely toxic to insects that come in contact with a wet spray, it is much more toxic after it has been ingested and metabolized.
Indoxacarb is the only approved oxadiazine insecticide, though the oxadiazine insecticide class is related to the pyrazoline-type insecticide class that includes the pyrethroids and other synthetic disruptors of the insect nervous system. Interestingly, pyrethroids and oxadiazine products work on similar parts of neurons in slightly different ways. This slightly different biochemical pathway keeps indoxacarb effective against pyrethroid-resistant insects.
What Insects Does Indoxacarb Control?
Indoxacarb is known to control a wide variety of agricultural pests, though no indoxacarb spray applications are available for consumer use. However, indoxacarb products have been created for the following home pest species:
How Does Indoxacarb Work?
Indoxacarb binds to and blocks the action of important proteins within nerve cells, known as voltage-dependent sodium channels. This is similar to the action of pyrethroid insecticides. By blocking these channels, nerve cells cannot balance the distribution of ions across their cell membranes.
This leads to an inability to transfer a nervous signal, much like the effect of an anesthetic drug. For insects, this insecticide works across so many nerves at once that it effectively shuts the entire nervous system down and kills the insects.
While pyrethroid compounds work in a similar manner, indoxacarb seems to work on a different set of proteins or binds to the ion channels in a different way. This is useful for insect control because it means that insects resistant to pyrethroids will not necessarily be resistant to indoxacarb.
Common Uses for Indoxacarb
This particular insecticide is the preferred spray chemical for a number of farmers harvesting apples, pears, tomatoes, broccoli, brussels sprouts, cabbage, cauliflower, eggplant, potato, lettuce, soybeans, alfalfa, and peanuts. Not surprisingly, all of these are crops that suffer from sucking and chewing insects, making indoxacarb very effective against their later life stages.
As a consumer product, indoxacarb is found in ant and termite granules and bait formulas, cockroach bait traps, and as a gel topical treatment for fleas on cats and dogs.
Unfortunately, regulators in the European Food Safety Authority have identified a large number of gaps in the scientific knowledge about the toxicity and safety of indoxacarb – from it’s toxicity to mammals to the amount of indoxacarb ingested by consumers of treated food products.
Humans (and other mammals) have an ability to break down indoxacarb in the body, making it much more toxic to insects at low levels.
Here, we break down studies that have observed the toxic effects of indoxacarb on various types of organisms.
Though not enough toxicity studies on mammals have been conducted, researchers have found that after 4 applications of indoxacarb, lettuce fields exposed field workers to levels of indoxacarb that were above the acceptable operator exposure level.
This means that agricultural operations need to be extremely cautious when using the chemical and need to let it dissipate before harvesting or otherwise working with a treated crop.
Further, the lack of study on the long term effects of indoxacarb on voles and other small mammals led the European Union to more strictly monitor the use of the pesticide on crops.
Indoxacarb is moderate to very highly toxic in almost all aquatic organisms – with as little as .024 mg/L being lethal to some fish species and important invertebrates.
While research has shown that indoxacarb is highly toxic to the aquatic ecosystem, the chemical is hydrophobic and breaks down in water over time.
So, if it is applied away from bodies of water it will likely not make it to a waterway. However, many governments regulate the use of indoxacarb on certain crops and near waterways to be safe.
In quail, this insecticide was found to be moderately toxic on a dietary basis, as low as 808 mg/kg. While a quail would have to ingest quite a bit of treated plant and insect material to reach this level of toxicity, it may be possible directly after a fresh application of the insecticide in a field or if a bird ingested a cockroach or ant bait trap.
Like many broad-spectrum insecticides, indoxacarb is highly toxic to bees. However, the creator of indoxacarb – DuPont – points to studies that suggest fields are safe for bees in as little as 3 hours after the application of indoxacarb.
However, much more research is needed to determine the long-term effects of indoxacarb on resident pollinator populations – especially since the larval forms of many butterfly and moth species are particularly sensitive to even small amounts of the chemical.
Though the carcinogen status of indoxacarb has not been sufficiently evaluated, it has been shown (and noted by the EPA) that lettuce seems to absorb and retain the most indoxacarb of all treated crops. Treated lettuce has nearly twice the allowable concentration the EPA recommends.
Indoxacarb Study Summaries
Indoxacarb may be a new addition to the pesticide arsenal, but many studies have already rigorously tested indoxacarb in a variety of different situations against many insects!
Indoxacarb does seem to be effective on ants and termites in part due to horizontal transfer – when an insect that has come into contact with indoxacarb exposes other insects within the colony.
In the lab, as little as 100 nanograms on a single insect can lead to 100% mortality of a colony within 20 days. While indoxacarb was also 100% effective as a cockroach bait, it took nearly twice as long for cockroaches to die off, compared to similar applications of fipronil and clothianidin.
As a flea treatment, indoxacarb is extremely effective. In one study, researchers found that indoxacarb treatment was 100% effective in eliminating all fleas present for up to 30 days.
As a topical formula, the indoxacarb sits on the surface of your pet’s skin and is subsequently ingested by fleas when they bite. This inoculates the fleas with indoxacarb, killing them a short time after. Other studies have confirmed indoxacarb’s efficacy in a challenging flea-infestation environment.
Insect Resistance to Indoxacarb
Studies have shown that indoxacarb-treated insect populations can develop resistance to the insecticide in as little as 3 generations. After resistance has been developed, it takes up to 118-times more concentrated indoxacarb to kill insects.
However, only limited levels of cross-resistance were found with pyrethroid insecticides, suggesting these products could work in sequence to successfully eliminate pest populations.
Other studies in moth populations have shown that indoxacarb resistance was developed in certain moth populations, but not others. Unfortunately, the resistant populations developed an extremely high level of resistance – rendering indoxacarb almost completely ineffective.
Indoxacarb has been shown to be slightly more effective at killing termites than another popular chemical, chlorantraniliprole. While chlorantraniliprole is more effective in the lab, indoxacarb seems to be more effective at killing termites when applied to soils in the field. This may be due to indoxacarb’s increased toxicity when it is ingested and metabolized by digging termites.
Specificity For Actively Feeding Insects
While indoxacarb affects nearly all insects it is directly applied to, it seems to be much more effective when it is ingested by growing insects. Studies in cabbage loopers (a species of moth) showed that indoxacarb has almost no effectiveness against eggs or the first larval stage of the insects.
Though the first larval stage does feed, they are so small that they consume very little indoxacarb. It is only the second or third instar larvae that begin to eat enough indoxacarb to experience toxic effects.
Indirect exposure may not be as harmful to insects that do not directly ingest the chemical. In another instance, a study found that indoxacarb had few effects on an important parasitic wasp (Trichogramma brassicae) that helps control pest insect populations. For this reason, indoxacarb is sometimes preferred over other insecticides with a less-specific mode of action.
This is part of the reason people claim that indoxacarb is “better for the environment” – because it may have fewer off-target effects. However, other studies have shown that the insecticide is acutely toxic to a wide number of aquatic species and can easily disrupt aquatic environments. So, it really depends on how indoxacarb is used.
Is Indoxacarb Banned by Any Countries?
Indoxacarb is subject to a complex array of partial-bans globally, though it seems to retain many uses across both agricultural and consumer markets. In the United States, the EPA allows indoxacarb as a crop insecticide, given that final consumer products do not contain more than 15 parts per million indoxacarb. This is an extremely small amount, usually achieved by letting indoxacarb degrade naturally before harvest.
In Europe, indoxacarb is approved for many uses as well – though it received a restricted renewal in 2019 when scientists noted its possible long-term risk to herbivorous mammals, earthworm-eating mammals, and honeybees.
China and India have also allowed indoxacarb in various applications, though its use near waterways and swampy areas is typically restricted due to its high toxicity to aquatic organisms.