At a glance
| Chemical family | Organochlorine insecticide; technical endosulfan is a two-diastereoisomer mixture, not a single pure substance |
| CAS number | 115-29-7 (technical endosulfan, a two-diastereoisomer mixture; alpha-endosulfan 959-98-8, beta-endosulfan 33213-65-9; the metabolite endosulfan sulfate is 1031-07-8) |
| Classification | Not evaluated by IARC. Stockholm Convention Annex A (elimination). EU harmonised classification Acute Tox. 2 by inhalation, H330 — fatal if inhaled |
| Where you encounter it | Farm and field residue: soil and dust tracked indoors, drift from treated land, and long-range atmospheric transport. Never a residential product, never a textile or foam input |
| Sleep micro-environment relevance | Low and indirect. Detected in indoor air of occupied housing years after registrations lapsed, but found in under 25% of dust samples even in farm households |
Regulatory & certification status
Where endosulfan stands across the major regulatory systems. Each row names the governing instrument; where a jurisdiction's record could not be opened directly, that is stated rather than guessed at.
| European Union | Banned. Listed in Annex I Part A of Regulation (EU) 2019/1021, the POPs Regulation, so manufacture, placing on the market and use are prohibited. The entry covers CAS 115-29-7, 959-98-8 and 33213-65-9 under EC 204-079-4. One exemption is recorded: articles already in use before or on 10 July 2012 that contain endosulfan may still be placed on the market and used. Annex I is a genuine prohibition, unlike the REACH Candidate List, which only identifies a substance. Regulatory — Regulation (EU) 2019/1021 Annex I |
| European Union — CLP | Harmonised classification exists at Annex VI index 602-052-00-5, introduced by Commission Regulation (EC) No 790/2009: Acute Tox. 2 (H330, fatal if inhaled), Acute Tox. 2 (H300, fatal if swallowed), Acute Tox. 4 (H312), Aquatic Acute 1 (H400) and Aquatic Chronic 1 (H410), pictograms GHS06 and GHS09, signal word Danger. There is no harmonised CMR or STOT classification. That records what has been formally harmonised, not a finding that those endpoints are clear: Annex VI covers only the harmonised subset and everything outside it is industry self-classification. Regulatory — Commission Regulation (EC) No 790/2009 |
| United States | EPA classified endosulfan a restricted-use pesticide and it was never approved for residential use. EPA signed a Memorandum of Agreement with the registrants in July 2010 ending all US uses; the final uses, including livestock ear tags, pineapple, perennial strawberries and vegetable crops grown for seed, terminated 31 July 2016. IRIS holds a chronic oral reference dose of 6 × 10-3 mg/kg-day, last updated 1994, and records the inhalation reference concentration as not assessed. NTP has not classified it. It is not listed under California Proposition 65. NIOSH recommends 0.1 mg/m³ in workplace air over a 10-hour day; OSHA has set no legal limit. Regulatory — US EPA IRIS |
| Canada | Not on CEPA Schedule 1, the List of Toxic Substances, and therefore outside the Prohibition of Certain Toxic Substances Regulations, 2025 (SOR/2025-270), whose text does not name it. Those Regulations reach only substances that are both on CEPA Schedule 1 and in column 1 of their own Schedule 1. Endosulfan is controlled instead at item 34 of Part 2 of CEPA Schedule 3, the Export Control List, amended by SOR/2026-28 to name the technical substance and both isomers. Registrations were cancelled by Health Canada's PMRA under the Pest Control Products Act, Re-evaluation Note REV2011-01; the PMRA record could not be opened from here, so no final Canadian use date is published. Regulatory — CEPA 1999 Schedule 3, Part 2, item 34 |
| United Kingdom | Great Britain applies assimilated Regulation (EU) 2019/1021, whose Annex I Part A carries the same endosulfan entry, the same three CAS numbers and the same exemption for articles in use on or before 10 July 2012. Northern Ireland continues to apply the EU Regulation. Separately, endosulfan was refused inclusion in Annex I to Directive 91/414/EEC by Commission Decision 2005/864/EC of 2 December 2005, which withdrew plant-protection authorisations six years before the POPs prohibition took effect. Regulatory — legislation.gov.uk |
| Australia | Australia is a Party to the Stockholm Convention, under which endosulfan sits in Annex A. The APVMA is reported to have cancelled active-constituent approvals and product registrations, with a phase-out period following, but the APVMA review page and its cancellation report both timed out from this machine, so no Australian date is published here. Regulatory — Stockholm Convention Annex A |
| International | Stockholm Convention Annex A (elimination), listed as technical endosulfan and its related isomers by decision SC-5/3, adopted at COP-5 on 25–29 May 2011 and communicated to Parties on 27 October 2011. Specific exemptions at listing covered production by Parties entered in the Register of specific exemptions, and use on the crop-pest complexes listed under Part VI of Annex A. Regulatory — Stockholm Convention Secretariat |
What it is
Endosulfan is an organochlorine insecticide, used against aphids, fruit worms, beetles, leafhoppers, moth larvae and white flies on a wide range of crops. Regulatory — ATSDR 2015 One point matters before any number is quoted: CAS 115-29-7 is the technical material, a mixture of two diastereoisomers. Analytical papers report them separately as endosulfan I and endosulfan II, the EU POPs Annex and Canada's Export Control List name all three CAS numbers, and the persistent metabolite endosulfan sulfate carries a fourth. A single CAS does not cover the whole entry.
IARC has not evaluated endosulfan. It does not appear in the IARC list of agents classified through Volume 123, and ATSDR states independently that DHHS, EPA and IARC have not classified endosulfan as to its ability to cause cancer. Read that as an absence of assessment, not an absence of hazard. The EU has separately harmonised it as fatal if inhaled and fatal if swallowed.
Where it shows up
Not in the bed
Endosulfan was never a mattress, foam or textile input, and it was never registered for use inside a home. ATSDR names dietary intake as the main source of exposure for the general population. Nothing you buy for a bedroom has ever been a plausible source.
It travels, then it settles
Weber and colleagues describe endosulfan as one of the most abundant organochlorine pesticides in the global atmosphere, capable of long-range transport to remote locations such as the Arctic. Peer-reviewed — Weber et al. 2010 A compound with that behaviour reaches buildings it was never applied near. Closer to home, the ordinary routes do most of the work: soil and field dust carried in on shoes, and drift into homes near treated land.
Measurable indoors after the registrations lapsed
Vaezafshar and colleagues measured 28 particle-phase pesticides in the indoor air of 46 occupied units across seven Toronto social-housing buildings in 2017. Endosulfan I came back at concentrations 11 times higher than earlier residential studies in the United States and France had reported, measurements made up to 30 years earlier. Peer-reviewed — Vaezafshar et al. 2024 Semivolatile organochlorines sorb onto indoor surfaces and settled dust, so a building holds them long after supply stops.
What the research says
- Still present in occupied homes after the ban. Indoor-air endosulfan I in Toronto social housing in 2017 ran 11 times higher than prior residential studies. The paper reports a relative comparison, not an absolute concentration in the text. Peer-reviewed — Vaezafshar et al. 2024, DOI 10.1038/s41370-024-00665-y
- But uncommon in house dust, even on farms. Across 295 vacuum dust samples from 213 US farm-household participants, endosulfan sat in the under-25% detection group with aldrin and cyanazine. Farm households are the homes most likely to carry agricultural residue indoors. Peer-reviewed — Xie et al. 2024, DOI 10.1016/j.envint.2024.109123
- It travels far from where it was sprayed. Weber and colleagues describe endosulfan as one of the most abundant organochlorine pesticides in the global atmosphere and capable of long-range transport to remote locations such as the Arctic. That is why a crop chemical turns up in places no one applied it. Peer-reviewed — Weber et al. 2010, DOI 10.1016/j.scitotenv.2009.10.077
- Classified fatal if inhaled, with no inhalation benchmark. The EU harmonised entry is Acute Tox. 2, H330. EPA's IRIS record has a chronic oral reference dose of 6 × 10-3 mg/kg-day and records the inhalation reference concentration as not assessed under the IRIS Program. Presence has been measured; dose has no yardstick. Regulatory — US EPA IRIS; CLP Annex VI 602-052-00-5
The honest position is narrow. Endosulfan is a legacy agricultural residue that can reach a bedroom in tracked-in soil and settled dust. It is uncommon in the general housing stock, it does not persist indoors the way chlordane, heptachlor and dieldrin do, and where it does appear the source is outside the building rather than inside the bed.
What helps reduce it
Take shoes off at the door. Keep a washable mat there. Endosulfan reaches a bedroom in tracked-in soil and field dust, so interrupting that path is close to the whole intervention.
Vacuum with a sealed HEPA machine and damp-dust hard surfaces. Semivolatile organochlorines partition onto settled dust. Removing the dust removes the reservoir.
If you live near active or recently retired cropland, keep bedroom windows shut during spraying seasons and run filtration instead. Endosulfan reached homes by drift and atmospheric transport, not from anything indoors.
Older housing with a documented pest-control history deserves more attention than newer housing. The Toronto study reported its highest legacy-pesticide concentrations in 1970s buildings with active pest-eradication programmes.
If you want a number rather than a guess, a dust or indoor-air screen is the only way to get one. Endosulfan cannot be smelled, seen, or inferred from a product label.
What does NOT help
- Replacing a mattress or buying certified bedding. Endosulfan was never a mattress or textile input, so the bed is not the source.
- Reading mattress certifications for endosulfan. It will not appear on any of them, and its absence tells you nothing about what is in your dust.
- Airing a room out to clear it. Indoors it sits on surfaces and in dust rather than mainly in the gas phase, so ventilation alone leaves the reservoir in place.
- Treating the EU and Stockholm bans as an all-clear. The EU POPs Regulation still allows articles already in use before or on 10 July 2012 to be placed on the market and used, and no ban removes what already settled in a building.
- Reading "IARC has not evaluated it" as "IARC found it safe." It means no monograph was written. The EU has separately harmonised it as fatal if inhaled.
- Assuming an inhalation safety number exists. EPA has an oral reference dose for endosulfan and has never derived an inhalation reference concentration.
Open research questions
- No absolute indoor-dust concentration for endosulfan in North American or European homes was located for this page. Vaezafshar et al. give a relative comparison for indoor air; the absolute endosulfan I value sits in that paper's supplementary tables. Inferred — gap identified from the cited literature
- Why endosulfan turns up in indoor air at concentrations well above older residential studies while staying under 25% detection in farm-household dust. Air and dust are answering different questions here, and the two results have not been reconciled. Speculation
- Whether the ratio of the two isomers, or of endosulfan to its sulfate metabolite, can distinguish recent local application from long-range transport in an indoor sample. Speculation
- Health Canada PMRA Re-evaluation Note REV2011-01 could not be opened from this machine, so the final Canadian use date remains unconfirmed here. Inferred — source access limitation, not a finding
The exposure ledger for Endosulfan
One chemical, several public questions, answered from independent datasets and joined here — the environment it shows up in, the body burden it carries, how it is regulated, and what actually reduces it.
Detection and body-burden figures are occurrence data, not a personal measurement or a health diagnosis. Part of the Embr Exposure Ledger — an open, cross-dataset chemical join (download the data), reusable with attribution.
Where you meet Endosulfan across your home
The same compound turns up in more than one place you live. Here's where it shows up in Embr — each links to the full breakdown for that part of your home.
Citations
- Agency for Toxic Substances and Disease Registry (2015). Toxicological Profile for Endosulfan. U.S. Department of Health and Human Services, Public Health Service. atsdr.cdc.gov Regulatory
- Secretariat of the Stockholm Convention on Persistent Organic Pollutants (2011). Decision SC-5/3: Listing of technical endosulfan and its related isomers. United Nations Environment Programme. pops.int Regulatory
- European Parliament and Council of the European Union (2019). Regulation (EU) 2019/1021 on persistent organic pollutants (recast), Annex I Part A. Official Journal of the European Union; assimilated Great Britain text at legislation.gov.uk. legislation.gov.uk Regulatory
- European Commission (2009). Commission Regulation (EC) No 790/2009 amending Regulation (EC) No 1272/2008 (1st ATP to CLP) — Annex VI harmonised classification entry 602-052-00-5, endosulfan (ISO). eur-lex.europa.eu Regulatory
- U.S. Environmental Protection Agency (1994). Endosulfan; CASRN 115-29-7 — Integrated Risk Information System (IRIS) Chemical Assessment Summary. National Center for Environmental Assessment. cfpub.epa.gov Regulatory
- Vaezafshar S, Siegel JA, Jantunen L, Diamond ML (2024). Widespread occurrence of pesticides in low-income housing. Journal of Exposure Science & Environmental Epidemiology. DOI: 10.1038/s41370-024-00665-y (PMID 38909155) Peer-reviewed
- Xie S, Hofmann JN, Sampson JN, Josse PR, Madrigal JM, Chang VC, Deziel NC, Andreotti G, Keil AP, Ward MH, Beane Freeman LE, Friesen MC (2024). Quantitative measures of recent and lifetime agricultural pesticide use are associated with increased pesticide concentrations in house dust. Environment International, 193. DOI: 10.1016/j.envint.2024.109123 (PMID 39541787) Peer-reviewed
- Weber J, Halsall CJ, Muir D, Teixeira C, Small J, Solomon K, Hermanson M, Hung H, Bidleman T (2010). Endosulfan, a global pesticide: A review of its fate in the environment and occurrence in the Arctic. Science of The Total Environment. DOI: 10.1016/j.scitotenv.2009.10.077 (PMID 19939436) Peer-reviewed
Frequently asked questions
Is endosulfan in my mattress?
No. Endosulfan is a crop insecticide, and ATSDR states plainly that it was not approved for residential use. No mattress, pillow or bedding textile has ever had a reason to contain it. Where it turns up indoors it arrives from outside the building, in soil and field dust carried in on shoes or drifting in from treated land.
It was banned years ago. Why is it still measurable indoors?
Organochlorines are semivolatile: they sorb onto indoor surfaces and settled dust and leave a building slowly. Vaezafshar and colleagues sampled indoor air in 46 occupied social-housing units in Toronto in 2017, after the Canadian registrations had lapsed, and reported endosulfan I at concentrations up to 11 times higher than earlier residential studies in the United States and France. A ban stops new supply; it does not remove what already settled.
How common is endosulfan in house dust?
Uncommon, even where you would most expect it. Xie and colleagues vacuumed 295 dust samples from US farm households and put endosulfan in the under-25-percent detection group alongside aldrin and cyanazine. Chlordane, heptachlor and dieldrin stay routinely detectable in homes for decades; endosulfan does not persist indoors in the same way.
Is there a safe indoor air level for endosulfan?
No number exists to answer that. The EU has harmonised endosulfan as Acute Tox. 2 by inhalation, H330, fatal if inhaled. EPA's IRIS record carries a chronic oral reference dose of 6 × 10-3 mg/kg-day but records the inhalation reference concentration as not assessed under the IRIS Program. A compound classified as acutely toxic by inhalation has no inhalation benchmark to compare a measurement against.
Related compounds
Embr is a sleep environment company researching and addressing the chemistry of the bedroom. Research and product development in progress.
Last reviewed 2026-07-25. If you find a factual error, contact us.