Insecticidal dusts are one of the most effective pest control measures for both professional exterminators and DIYers. These dusts come in ready-to-use formulations and typically retain their insect-killing power over long periods, sometimes for months after application.
Insecticidal dust is extremely versatile for pest control because it can be dispersed to cover a wide area easily, quickly, and cheaply. With a small hand-held billow duster, you can spray into holes, burrows, and nests with much greater coverage than a wet spray could achieve.
What makes Delta Dust unique though is that it’s the only insecticidal dust that can be used in moist areas.
What is Delta Dust?
Delta Dust is a ready-to-use insecticide manufactured by Bayer. The insecticide is effective for exterminating a wide range of crawling and flying insects and is approved for indoor and outdoor use.
Delta Dust is the only 100% waterproof dust insecticide on the market. It is odorless and kills insects for up to 8 months if left undisturbed.
The dust does not absorb moisture or clump which makes it the dust of choice for pests that prefer moist environments (such as roaches) or insects that like to build outdoor underground nests (such as wasps).
Delta Dust is a broad-spectrum insecticide which kills a wide range of pests including bees, ants, carpenter ants, boxelder bugs, carpet beetles, carpenter bees, cockroaches (including resistant and non-resistant strains), centipedes, crickets, fleas, confused flour beetles, drugstore beetles, granary weevils, grain mites, firebrats, saw-toothed grain beetles, red flour beetles, silverfish, scorpions, termites, sowbugs, tobacco moths, wasps, warehouse moths, yellow mealworms, and webbing clothes moths among other pests.
How Does Delta Dust Kill Insects?
Delta Dust is very effective at killing insects because of its active ingredient, Deltamethrin. This insecticide interferes with the proper functioning of the pest’s nervous system, eventually killing it. It works pretty quickly killing most bugs within 24-48 hours.
For Delta Dust to start working on the insects it needs to come into contact with the bugs or be ingested by the bug. As a result, for Delta Dust to be effective on flying insects you should try to get it into their nest area.
Deltamethrin is a synthetic pyrethroid insecticide that is very similar in structure to natural pyrethrins such as pyrethrum. This pyrethroid works on contact or through ingestion and begins to work almost immediately.
The active ingredient attacks the insect’s central nervous system and over-stimulates the nerve cells to cause paralysis. The paralyzed insect is rendered unable to perform its regular bodily functions including feeding and dies from any number of causes including starvation.
Deltamethrin (and other pyrethroids) contains much higher levels of toxicity than pyrethrins and therefore more effective for controlling insects.
Deltamethrin entered the market in 1978 and was largely used for agricultural applications. Today, many commercial insecticide products contain deltamethrin including ones formulated for indoor use. Deltamethrin comes in a variety of formulations in insecticide products including wettable powders, granules, dusts, sprays, and aerosols.
Pyrethrins are naturally occuring while pyrethroids are man-made.
How to Apply Delta Dust
Safety precautions: Avoid contact with skin, eyes, and clothing. Please wear gloves, face mask, and eye protection before using. Keep away from children and pets. Store in a cool, dry place and in its original container.
The best way to apply delta dust is to use a hand duster or power duster. You need roughly 2-3 grams of Delta Dust per square yard or 0.5lbs. per 1,000 sq. ft of floor space.
Apply a thin layer of the dust, uniformly, to places where you know the insects are nesting or along trails in the case of ants.
Focus on pest hot spots including behind cabinets, around water and sewer pipes, around electrical and telephone fittings, around door frames and windows, in attics and crawlspaces, along baseboards, in wall voids, and directly to cracks and crevices.
You can also spray the insecticide dust into nests and ground nests and use it in a variety of places including in animal quarters, recreational vehicles and mobile homes, on ornamental plants, in greenhouses, and on vegetables and plants.
You can find detailed instructions on how to treat various insects indoors and outdoors here.
Tips for Using a Hand Duster
Do not fill the hand duster to the brim with powder. Instead, fill it halfway or about two-thirds full. The space allows for good air to dust ratio which gives you even, thin, and mess-free application.
Shake the duster slightly after each squeeze to get the dust suspended inside the duster.
Use a hand duster with a rubber, plastic, or fiberglass spout, or put a rubber hose over the metal tip. This feature helps to protect against electric shocks when treating electrical outlets or around electrical wires.
Remove the tip of the duster from cracks or crevices before relaxing your grip on the applicator. This will help to avoid sucking up dust, lint, and debris which can clog your duster.
Squeeze the duster gently to apply thin, even layers of insecticide dust.
How safe is Delta Dust?
Delta Dust is EPA approved for indoor and outdoor use and is generally safe to use if you follow the product instructions. The U.S. EPA classifies deltamethrin, the active ingredient in Delta Dust, as “not likely to be a human carcinogen.”
Overexposure to Delta Dust can, however, cause mild to severe side-effects depending on the nature of exposure.
Inhalation: Symptoms include rapid heartbeat, dizziness, headache, and respiratory irritation.
Ingestion: Symptoms include abdominal pain, vomiting, nausea, and muscle twitches.
Skin contact: Symptoms include tingling, numbness, or burning sensation on the area of contact. Rinse the skin with lots of water for at least 15 minutes to relieve the symptoms.
Generally speaking, deltamethrin has low to moderate toxicity to mammals including humans and you shouldn’t have any problems if you follow the product instruction and use proper safety gear.
A pet ingesting a large amount of Delta Dust may experience drooling, lack of coordination, muscle tremors, and vomiting. The pet may also scratch, bite, or lick the contact area excessively if the product gets on their skin.
Delta Dust and the Environment
Delta Dust degrades relatively quickly in the soil and has a half-life of anywhere from 5-209 days depending on a variety of factors including water content in the soil, soil chemistry, and temperature. The insecticide has a much longer half-life in soils with abundant organic material and in soils with high clay content.
Delta Dust also binds tightly to soil particles making it unlikely to be taken up by plants.
Deltamethrin is highly toxic to aquatic life, however. Do NOT use the pesticide around storm drains, surface waters, gutters, and drainage ditches. Also, use this product when the weather is calm and there is no prediction of rain for the next 24 hours.
Deltamethrin is also proven to be toxic to honeybees in laboratory conditions. Field studies, however, did not show any harm to the bees although the deltamethrin-based products did repel the bees.
Either way, use the product sparingly and/or carefully around bees and where they work or nest given the rapidly shrinking bee population.