At a glance
| Chemical family | Organochlorine insecticide |
| CAS number | 50-29-3 |
| Classification | IARC Group 2B — possibly carcinogenic to humans; Stockholm Convention POP (Annex B, restricted) |
| Where you encounter it | Was sprayed directly on mattresses, bedding, and interior walls for mosquito and insect control; still used for indoor residual spraying (IRS) in malaria-endemic regions |
| Sleep micro-environment relevance | Persistent in household dust decades after use; the bedroom was literally a primary application site |
Regulatory & certification status
Where DDT stands across the major regulatory systems and the certifications a bedroom product might carry. Each row links to the governing instrument; where a jurisdiction has no specific measure, that is stated plainly rather than left blank.
| Stockholm Convention | Annex B (restriction) — permitted only for disease vector control under WHO guidelines. The exemption is reviewed regularly and intended to phase out as alternatives become available. Regulatory |
| European Union | Banned for all uses; listed under the EU POPs Regulation. No exemptions for any application within the EU. Regulatory |
| United States | EPA cancelled all uses in 1972 — one of the first major EPA regulatory actions and a landmark in environmental law. Regulatory |
| Canada | Cancelled all registrations under the Pest Control Products Act. Prohibited under the Prohibition of Certain Toxic Substances Regulations, 2025 (SOR/2025-270), which came into force 30 June 2026 — manufacture, use, sale and import are banned. Regulatory — Justice Laws |
| OEKO-TEX STD 100 | Screened as an organochlorine pesticide; restricted at strict limits in finished textiles. Industry |
What it is
DDT is a synthetic organochlorine insecticide first synthesised in 1874 and deployed at scale from the 1940s. Its effectiveness against mosquitoes and other insect vectors made it one of the most widely used pesticides in history. Its environmental persistence — DDT and its metabolite DDE resist degradation for years to decades — and its tendency to bioaccumulate up food chains eventually led to widespread bans. Peer-reviewed — IARC Monographs Vol. 113
IARC classifies DDT as Group 2B (possibly carcinogenic to humans). The epidemiological evidence links DDT exposure to liver cancer and non-Hodgkin lymphoma, though the evidence is not considered sufficient for a higher classification.
How it relates to the bedroom
The bedroom was the application site
DDT was sprayed directly on mattresses, bed frames, bedding, and interior walls as standard practice for mosquito and bed-bug control from the 1940s through the 1970s in many countries. This was not incidental contamination — the bedroom was the target. Indoor residual spraying (IRS) placed the insecticide precisely where people slept, because that is where mosquitoes bite.
Still present in household dust
Because DDT and its metabolite DDE are extraordinarily persistent, household dust in homes where DDT was historically applied — or near agricultural areas where it was sprayed — still contains measurable residues decades later. The half-life of DDT in indoor environments is measured in years to decades. The levels are typically low, but they are persistent and detectable. Inferred — persistence from known environmental half-life data applied to indoor settings
Still used for malaria control
In malaria-endemic regions, indoor residual spraying with DDT continues today under WHO protocols. Regulatory — WHO Position Statement 2011 The Stockholm Convention grants this specific exemption because DDT remains one of the most effective and affordable tools for reducing malaria transmission, and malaria kills hundreds of thousands of people annually. This is a genuine public-health trade-off — not regulatory oversight or failure.
What the research says
- IARC Group 2B — possibly carcinogenic. Epidemiological evidence links DDT to liver cancer and non-Hodgkin lymphoma, but is not considered sufficient for a higher classification. Peer-reviewed — IARC 2018
- Environmental persistence is extreme. DDT and DDE resist degradation for decades in both outdoor and indoor environments. Peer-reviewed
- The malaria exemption reflects a real trade-off. WHO continues to recommend DDT for IRS where alternatives are insufficient, with the goal of eventual phase-out. Regulatory — WHO 2011
What helps reduce it
Dust control. In homes where DDT was historically applied, regular wet-cleaning of floors and surfaces reduces dust-bound DDT/DDE exposure. Dry sweeping can re-suspend dust particles.
HEPA filtration. HEPA air purifiers and vacuum cleaners with HEPA filters capture fine dust particles that carry persistent organic pollutants including DDT residues.
Know your home's history. If your home was built before the 1970s in a region where DDT was used for residential pest control, DDT residues in household dust are plausible. Testing is available through environmental labs.
What does NOT help
- Replacing the mattress alone. DDT residues are in household dust, not in modern mattress materials. A new mattress in a contaminated room will accumulate the same dust.
- Assuming it is gone because it was banned decades ago. DDT's persistence means "banned" and "absent" are not the same thing. The half-life measured in decades means measurable levels remain long after the last application.
Open research questions
- Quantified DDT/DDE levels in household dust of pre-1970s homes across different regions, and the contribution of dust-bound exposure to total body burden. Speculation
- Timeline and feasibility of DDT alternatives achieving equivalent malaria-vector efficacy in all settings where DDT IRS is currently used. Speculation
Citations
- IARC (2018). DDT, Lindane, and 2,4-D — Group 2B. IARC Monographs Vol. 113. Peer-reviewed
- Stockholm Convention on Persistent Organic Pollutants — DDT listing, Annex B (restricted use for disease vector control). Regulatory
- WHO (2011). The use of DDT in malaria vector control — WHO Position Statement. Regulatory
Frequently asked questions
Is DDT still in my home?
If DDT was ever applied in your home — which was common practice through the 1970s in many countries — measurable DDT and DDE (its primary metabolite) are almost certainly still present in household dust. DDT's half-life in indoor environments is measured in years to decades. The levels are typically low, but they are persistent and detectable.
Why is DDT still allowed anywhere?
The Stockholm Convention grants a specific exemption for indoor residual spraying in malaria-endemic regions because DDT remains one of the most effective tools for reducing malaria transmission, and malaria kills hundreds of thousands of people annually. The exemption is reviewed regularly and is meant to phase out as alternatives become available. This is a genuine public-health trade-off, not regulatory failure.
Related compounds
Embr is a sleep environment company researching and addressing the chemistry of the bedroom. Research and product development in progress.
Last reviewed 2026-07-07. If you find a factual error, contact us.