At a glance
| Chemical family | Synthetic pyrethroid — Type II (alpha-cyano group; one of the most potent pyrethroids by weight) |
| CAS number | 52918-63-5 |
| Classification | Not classified by IARC. WHO Class II (moderately hazardous). WHO-approved for insecticide-treated bed net impregnation. EU CLP Acute Tox. 3 (H301, oral), Aquatic Acute 1 / Chronic 1 |
| Where you encounter it | Professional bed bug and pest treatment (mattress seams, bed frames); insecticide-treated bed nets (ITNs) for malaria prevention; agricultural pest control; mosquito control programmes |
| Sleep micro-environment relevance | Applied directly to mattresses, bed frames, and bed nets — the most direct bedroom pesticide exposure pathway. WHO-approved for sleeping under treated nets |
Regulatory & certification status
| European Union | Approved active substance under the Plant Protection Products Regulation. Authorised under the Biocidal Products Regulation for insect control. CLP Acute Tox. 3 (H301). Regulatory |
| United States | EPA-registered insecticide for residential and agricultural use. Used in bed bug treatment protocols. Not classified as a carcinogen by EPA. Regulatory |
| Canada | PMRA-registered for residential and agricultural use. Regulatory |
| International | WHO Class II (moderately hazardous). WHO Prequalification approved for insecticide-treated bed nets. Not IARC classified. Approved for indoor residual spraying for malaria vector control. Regulatory |
What it is
Deltamethrin is a single-isomer synthetic pyrethroid — it is the most insecticidally active of the eight possible isomers of its parent compound. This makes it one of the most potent pyrethroids by weight: effective doses against insects are measured in milligrams per square metre. Like cypermethrin, deltamethrin is a Type II pyrethroid (contains an alpha-cyano group) that blocks voltage-gated sodium channels in insect neurons. IARC has not evaluated deltamethrin for carcinogenicity. Its mammalian toxicity is relatively low — the selectivity between insect and mammalian sodium channels provides a safety margin. WHO approves deltamethrin for impregnation of bed nets, where people sleep in direct contact with treated fabric for 8+ hours nightly.
Where it shows up in bedding
Deltamethrin has two direct bedroom applications. First, it is applied by pest control operators to mattress seams, bed frames, and headboard crevices for bed bug control — creating residues on surfaces that the sleeper contacts. Second, and uniquely among pesticides, deltamethrin is deliberately incorporated into bed nets for malaria prevention in endemic regions. Long-lasting insecticidal nets (LLINs) are treated with deltamethrin at the factory and designed to retain insecticidal activity through 20+ washes. People sleep under and in contact with these treated nets nightly. WHO has determined that the health benefits of malaria prevention far outweigh the risks of deltamethrin exposure from treated nets.
Citations
- WHO (2023). Guidelines on Insecticide-Treated Nets. World Health Organization. Source Regulatory
- ATSDR (2003). Toxicological Profile for Pyrethrins and Pyrethroids. Source Regulatory
- EPA. Deltamethrin — Pesticide Fact Sheet. Source Regulatory
Frequently asked questions
Is sleeping under a deltamethrin bed net safe?
WHO has determined that the health benefits of sleeping under a deltamethrin-treated bed net in malaria-endemic areas far outweigh the risks of deltamethrin exposure. Extensive studies of people sleeping nightly under treated nets have not found significant adverse health effects. The low mammalian toxicity of pyrethroids and the selectivity of deltamethrin for insect sodium channels provide a safety margin.
How potent is deltamethrin compared to other pyrethroids?
Deltamethrin is one of the most potent pyrethroids by weight — it is effective against insects at lower concentrations than permethrin or cypermethrin. This is because deltamethrin is a pure single isomer with maximal insecticidal activity, while other pyrethroids are mixtures of less active isomers. Its higher potency means lower application rates, which can reduce total chemical exposure.
Related compounds
Embr is a sleep environment company researching and addressing the chemistry of the bedroom. Research and product development in progress.
Last reviewed 2026-07-08. If you find a factual error, contact us.