Desiccant Dusts
Insecticidal dusts that kill by physically abrading the waxy cuticle causing dehydration - cannot be resisted and provide permanent control if kept dry.
Detailed Overview
Desiccant dusts (diatomaceous earth, silica aerogel, amorphous silica) kill through physical mode of action - absorb waxy protective coating from insect cuticle causing death by dehydration. Unlike chemical insecticides affecting nervous system, desiccants work mechanically making resistance impossible. Microscopic sharp particles abrade cuticle, waxy layer absorbed by dust, moisture escapes body, insect dies of dehydration in hours to days. Highly effective against: cockroaches, bed bugs, fleas, ants, silverfish, carpet beetles, and stored product pests. Ineffective against pests with hard shells (beetles) or those not susceptible to dehydration. Critical: must be applied as light dust - heavy piles avoided by pests. Permanent control if dust remains dry - can last decades in dry voids. Ineffective in wet locations where dust becomes saturated. Best applications: wall voids, attics, crawl spaces, electrical conduits, under appliances. Food-grade diatomaceous earth labeled for use in food facilities. Silica gel formulations (CimeXa, MotherEarth D) more effective than DE for bed bugs and cockroaches. Combine with chemical treatments for comprehensive programs - dusts provide permanent void protection while chemicals give immediate results.
When to Use
Apply light dust to dry voids, attics, wall cavities, and concealed areas for permanent control. Best for bed bugs, roaches, and insects in protected harborage. Cannot be used in wet areas.
Required Skill Level
Requires some training and experience in pest management
Benefits
- Physical kill - resistance impossible
- Permanent control if kept dry
- Longest residual of any product type
- Effective against chemically-resistant pests
- Low toxicity to mammals
- Cost-effective long-term solution
Limitations
- Slow kill - hours to days
- Completely ineffective when wet
- Must apply as light dust - technique critical
- Not for rapid knockdown situations
- Can create airborne particles if over-applied
- Limited to dry protected areas
Related Concepts
Other product types that may be useful
Reduced-Risk Pesticides
Low-toxicity pesticide products that pose minimal risk to humans, pets, and the environment while remaining effective against target pests.
Insect Growth Regulators (IGRs)
Pesticides that disrupt insect development and reproduction by mimicking or blocking growth hormones - providing long-term population suppression.
Non-Repellent vs Repellent Chemistry
Understanding the difference between insecticides pests cannot detect (non-repellent) versus those they avoid (repellent) - critical for colony elimination.