At a glance
| Chemical family | Indoor Air VOCs (BTEX aromatic) |
| CAS number | 100-41-4 |
| IARC classification | Group 2B (possibly carcinogenic to humans) |
| Activated carbon capture | Moderate — adsorbs reasonably well on standard activated carbon |
| Evidence strength | Strong |
| Primary audience | Firefighters, general population |
Regulatory & certification status
Where Ethylbenzene 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.
| European Union | Ethylbenzene (CAS 100-41-4; EC 202-849-4; Index 601-023-00-4) has a harmonised CLP classification in Annex VI: Flam. Liq. 2 (H225), Acute Tox. 4 (H332), STOT RE 2 (H373, hearing organs) and Asp. Tox. 1 (H304) — notably NOT a harmonised carcinogen category (Note P applies regarding benzene content). It does not appear on the REACH Candidate List of SVHC, the Authorisation List (Annex XIV) or the Annex XVII restriction list, and it is not listed under the EU POPs Regulation. (The ECHA Candidate List page is bot-blocked to automated retrieval, so the SVHC-absence is reported conservatively from the consolidated list rather than a single fetched line.) Regulatory — ECHA · ECHA CHEM |
| United States | California Proposition 65: ethylbenzene is listed as a chemical known to the State to cause cancer, effective 11 June 2004, via the Authoritative Bodies mechanism (IARC). OEHHA has adopted No Significant Risk Levels (NSRLs) of 41 µg/day (oral) and 54 µg/day (inhalation). Federal TSCA: on 18 December 2024 EPA initiated the prioritization process for ethylbenzene (one of five candidate chemicals named that day, alongside benzene, naphthalene, styrene and 4-tert-octylphenol) and opened a 90-day public comment period; as of this record ethylbenzene is still in the prioritization process ('initiated / pending proposed designation') and has NOT been finalized as a High-Priority Substance. Regulatory — OEHHA |
| Canada | Ethylbenzene was assessed under the CEPA 1999 Chemicals Management Plan. The Final Screening Assessment, published 30 April 2016, concluded that ethylbenzene does not meet any of the criteria in section 64 of CEPA (i.e. it is not 'toxic' under the Act), while noting non-cancer effects of concern on the auditory system at higher exposures. It is therefore NOT on CEPA Schedule 1 (List of Toxic Substances). Regulatory — Government of Canada |
| Australia | Ethylbenzene is an industrial chemical regulated under AICIS (which replaced NICNAS on 1 July 2020). No specific AICIS evaluation outcome or IChEMS scheduling/decision could be confirmed against a primary government source. Regulatory — AICIS |
| United Kingdom | Under GB CLP, Great Britain carried over the EU Annex VI harmonised classifications that applied at the end of the transition period into the GB Mandatory Classification and Labelling (GB MCL) list, so ethylbenzene carries the same mandatory entry (Flam. Liq. 2, Acute Tox. 4, STOT RE 2, Asp. Tox. 1; no harmonised carcinogen category). No UK REACH SVHC / Authorisation / restriction action specific to ethylbenzene was identified. Regulatory — HSE |
| International | IARC classifies ethylbenzene as Group 2B, possibly carcinogenic to humans (Monographs Volume 77, 2000), on the basis of inadequate evidence in humans and sufficient evidence in experimental animals. No Stockholm Convention (POPs) or Minamata Convention listing applies. Regulatory — IARC Monographs Vol. 77 (2 · IARC |
| Certifications | CertiPUR-US: prohibits ozone-depleters, certain heavy metals, certain flame retardants, formaldehyde and phthalates and sets a low-VOC emissions requirement for certified foam — it does not name ethylbenzene specifically, but a foam emitting ethylbenzene would count toward its total-VOC limit. OEKO-TEX Standard 100: regulates aromatic-solvent residues and total VOC/odour in textiles — an indirect limit rather than a named-ethylbenzene threshold. GREENGUARD / GREENGUARD Gold: a low-VOC emissions certification in which ethylbenzene is one of the individual VOCs measured and counts toward the TVOC limit; it is not singled out by name in the headline criteria. Industry — CertiPUR-US · OEKO-TEX |
| The 72-hour test window | Well captured. Ethylbenzene is a volatile aromatic hydrocarbon (VOC) that off-gasses into air, so a short ~72-hour emissions chamber test readily detects it as an individual VOC peak rather than relying on dust migration. Inferred — from the compound's volatility/emission profile versus the VOC focus of short chamber tests |
What it is
Ethylbenzene — CAS 100-41-4 — is a single-ring aromatic hydrocarbon, structurally a benzene molecule with one ethyl group attached. It is part of the BTEX family (Benzene, Toluene, Ethylbenzene, Xylenes) — four aromatic VOCs that almost always appear together in indoor air measurements because they share sources and chemical behavior.
Where you encounter it
Ethylbenzene is present in gasoline, petroleum-based solvents, paint thinners, varnishes, some adhesives, and as a combustion product. It is also a precursor in the production of styrene and therefore appears in some plastic-related off-gassing. Indoor air studies routinely detect ethylbenzene in residential settings, particularly in homes with attached garages, recent paint or solvent use, or significant outdoor traffic infiltration. Peer-reviewed — multiple indoor air quality surveys
Why it matters for sleep environments
IARC classifies ethylbenzene as Group 2B (possibly carcinogenic to humans) based on animal studies showing kidney and liver tumors. Peer-reviewed — IARC Monograph 77 For occupational populations — firefighters, painters, gas station workers — exposure can be substantial. For typical residential bedrooms, concentrations are usually well below health-effect thresholds, but the compound's persistence and its appearance with the rest of the BTEX cluster make it worth tracking.
The Atlas covers ethylbenzene as part of the broader BTEX family because the four compounds are essentially never present in isolation — and because the BTEX signature is one of the cleanest indicators of fuel-derived or combustion-derived indoor air contamination.
Related compounds
This is a preview of an Atlas entry under development. Last reviewed 2026-05-19. If you find a factual error, contact us.