At a glance
| Chemical family | Anhydrosugar; cellulose pyrolysis product |
| CAS number | 498-07-7 |
| IUPAC name | 1,6-Anhydro-β-D-glucopyranose |
| IARC classification | Not classified by IARC. Levoglucosan is a molecular fingerprint, not a hazard. The hazardous compounds in biomass-burning smoke are the co-deposited PAHs, fine particulate matter, combustion VOCs, and metals — all covered as their own Atlas entries. |
| Formation | Cellulose pyrolysis above ~300°C (Simoneit 2002). Produced by all biomass combustion: wildfire, residential wood stoves, prescribed burns, agricultural and yard waste burning. Yan et al. 2018 documented residential coal combustion as a secondary source, complicating source attribution in regions with solid-fuel residential heating. |
| Atmospheric lifetime | 0.7–2.2 days under typical summer OH concentrations (Hennigan et al. 2010); somewhat longer when partitioned into particles or settled into dust where shielded from oxidant attack. |
| Indoor relevance | Marshall Fire (Boulder Co., Dec 2021) WUI fire produced indoor dust with median levoglucosan ~4,147 ng/g in homes inside the fire perimeter, six months post-fire — alongside elevated PAHs and metals (Silberstein 2023). Routinely measurable in homes with active woodstoves (Vicente 2019/2020). |
| Biomarker use | Surface and dust tracer — not a human biomarker. Urinary levoglucosan is not reliable for personal exposure assessment (Balogh et al. 2025); for that, urinary methoxyphenols (see guaiacol) are the validated tool. |
What it is
Levoglucosan is an anhydrosugar — chemically a dehydrated form of glucose — produced specifically when cellulose breaks down at high temperature. The molecule forms during the pyrolysis stage of biomass combustion, when wood, leaves, grass, and crop residue heat past about 300°C and the cellulose polymer chains depolymerize and rearrange. Because cellulose is a defining component of plant cell walls, and because the pyrolysis pathway that yields levoglucosan is essentially universal across plant material, the compound functions as a robust source-specific marker: detecting it in air or in settled dust documents that something plant-derived was burned and that its smoke reached the sampled environment. Peer-reviewed
The foundational identification of biomass-burning organic tracers, including levoglucosan, is in Simoneit 2002 in Applied Geochemistry — "Biomass burning — a review of organic tracers for smoke from incomplete combustion" — which remains the standard reference for the field. The chemistry distinguishes the major plant biomass categories: cellulose pyrolysis yields levoglucosan; lignin pyrolysis yields the methoxyphenols (guaiacol, syringol, and their substituted derivatives); conifer resin pyrolysis yields the resin acids (dehydroabietic acid and related diterpenoids). Source-apportionment studies typically measure several of these together to identify what fraction of indoor or outdoor particulate matter came from biomass burning and, in some cases, what type of vegetation burned. Peer-reviewed
Levoglucosan itself is not a hazardous compound. It is not classified by IARC, has no notable acute toxicity, and is sometimes used in food-related contexts as a flavor precursor. The reason it earns an Atlas entry is structural: when it appears in indoor dust at elevated concentrations, the hazardous mixture that traveled with it during the original smoke event also appears at elevated concentrations — and continues to expose anyone who lives in that space until the dust is cleaned and the reservoir is reduced.
How it gets to the bedroom
From wildfire smoke deposition
The most striking documentation of indoor levoglucosan deposition from a wildfire event comes from Silberstein et al. 2023 in Air Quality, Atmosphere & Health: "Residual impacts of a wildland urban interface fire on urban particulate matter and dust: a study from the Marshall Fire." The team sampled indoor dust from homes inside the Marshall Fire perimeter approximately six months after the December 2021 wildfire and reported median levoglucosan of 4,147 ng/g, alongside median ΣPAH (EPA priority) of 1,859.3 ng/g and median ΣMetals of 34.6 mg/g. The hazardous co-mixture was still clearly elevated in settled dust at the half-year mark. Where the levoglucosan was, the PAHs and metals were. Peer-reviewed
From residential wood combustion
Households with active woodstoves and wood fireplaces accumulate levoglucosan continuously throughout the heating season. Vicente et al. 2020 in Science of the Total Environment characterized the impact of residential wood combustion on indoor air quality and documented elevated levoglucosan alongside PM2.5, PAHs, and other combustion products. Ward and Noonan 2008 in Indoor Air measured residential indoor PM2.5 before and after a woodstove changeout intervention and documented substantial reductions in indoor particulate burden when older stoves were replaced — direct evidence that the wood-smoke marker chemistry is happening inside the home, not just outside it. Peer-reviewed
From the broader atmospheric transport pathway
Even homes far from active wildfires can accumulate levoglucosan when smoke is carried regionally. Hennigan et al. 2010 in Geophysical Research Letters measured an atmospheric lifetime of 0.7 to 2.2 days under typical summertime OH concentrations — long enough for smoke from a fire hundreds of miles away to reach a home and deposit its tracer chemistry through HVAC intake, window infiltration, and clothing transfer. The implication for residential exposure: a wildfire two states away can still leave a measurable fingerprint in your bedroom dust. Peer-reviewed
What the research says
Documented as the biomass-burning tracer
The classical chemistry of wood combustion organic compounds was characterized in a series of foundational papers by Hawthorne, Schauer, Cass, Fine, and Simoneit. Hawthorne et al. 1988 in ES&T identified the methoxyphenol class as candidate tracers. Schauer et al. 2001 in ES&T ("C₁–C₂₉ Organic Compounds from Fireplace Combustion of Wood") and Fine et al. 2002 in JGR Atmospheres (continental-scale characterization of residential wood combustion emissions) catalog levoglucosan among the consistent and abundant markers. The chemistry is settled; the analytical methods are mature; the source-attribution use is well-validated. Peer-reviewed
Source attribution caveats — stated honestly
Two important limitations are worth surfacing. First, Hedberg et al. 2006 in Journal of the Air & Waste Management Association — "Is Levoglucosan a Suitable Quantitative Tracer for Wood Burning?" — compared the compound against trace-element receptor modeling in a residential wood-burning city (Lycksele, Sweden) and concluded that while it serves well as a qualitative biomass-burning marker, its quantitative conversion to source-specific particulate mass carries non-trivial uncertainty. The compound is a fingerprint of presence; converting that fingerprint to a precise quantitative attribution requires careful auxiliary data. Peer-reviewed
Second, Yan et al. 2018 in ES&T — "Residential Coal Combustion as a Source of Levoglucosan in China" — documented that solid coal burning in residential stoves emits substantial levoglucosan, complicating the assumption that the compound is biomass-specific in regions where domestic coal use is common. In North American residential and wildfire contexts the biomass assumption holds well, but the source caveat is honest and should be stated. Peer-reviewed
Why it is NOT a personal biomarker
A common temptation is to assume that because levoglucosan is the standard environmental tracer, it should also work as a biomarker of personal smoke exposure via urine measurement. Balogh et al. 2025 in Toxics reviewed the question directly — "Levoglucosan and Its Isomers as Markers and Biomarkers of Exposure to Wood Burning" — and concluded that urinary levoglucosan is not a suitable biomarker for assessing residential wood smoke exposure: observed urinary concentrations are dominated by demographic and dietary background rather than by environmental smoke exposure. For personal smoke-exposure biomarker work — including the firefighter exposure assessment context — urinary methoxyphenols (see guaiacol) are the better-validated tool. Levoglucosan stays in the environmental side of the equation. Peer-reviewed
What helps reduce exposure
Tier 1 — most effective. The exposure-reducing actions target the co-deposited hazardous mixture, not the levoglucosan itself. After significant smoke events: vacuum soft surfaces (mattress top, pillows, carpets, upholstery) with a HEPA-filter vacuum; mop hard floors; dust hard surfaces with damp cloths; launder all washable bedding through multiple cycles; replace activated carbon air-cleaner filters. For severe contamination — homes inside a WUI fire perimeter, or homes affected by direct smoke ingress over days — replace mattresses, pillows, and upholstered furniture in the bedroom. See the flagship article The Smoke That Stays for the full surface-cleaning-vs-air-cleaning evidence and timescale.
Tier 2 — ongoing for woodstove households. Maintenance and operation matter for wood-burning households. EPA-certified stoves emit substantially less than older models (Ward 2008 changeout data); good draft and proper seasoning of fuel reduce smoldering, which is when the biomass-burning marker chemistry runs hottest. Run HEPA + activated carbon filtration during the heating season; vacuum and dust more frequently than baseline in homes with active wood heat.
Tier 3 — measurement to document remediation. For households doing thorough post-fire remediation, indoor dust testing for levoglucosan, PAHs, and metals provides an audit trail. The Silberstein 2023 protocol is the methodological reference. Standard analytical chemistry can measure levoglucosan at the nanogram-per-gram level from a small dust sample.
What does NOT help
Air freshening does not address dust-bound markers. Levoglucosan and its hazardous co-mixture sit in settled dust and on surfaces; fragrance products do not remove them.
Activated carbon air cleaners alone are insufficient. Carbon filtration handles the airborne fraction in real time; it does not reach the dust reservoir that re-emits and resuspends. The Li/Farmer 2023 surface-cleaning finding documented in the flagship applies directly.
Waiting for the smell to fade is not waiting for the chemistry to leave. The Silberstein 2023 indoor dust measurements were six months post-fire. Olfactory decline does not track marker persistence.
A urinary levoglucosan test will not document your personal exposure reliably. Balogh 2025 reviewed this directly. For personal biomarker measurement in smoke-exposure contexts, urinary methoxyphenols (see guaiacol) are the validated tool; for tobacco-specific exposure, cotinine serves the analogous role.
Open research questions
- The dose-response relationship between indoor levoglucosan concentration and quantified health outcomes in residents of post-fire homes has not been characterized — levoglucosan itself is not the harmful agent, and the co-mixture (PAHs, metals, PM2.5) is what drives the disease signal. Disentangling these contributions at the residential exposure level is an active area. Inferred
- The Silberstein 2023 Marshall Fire measurements are six-month post-fire snapshots. The full decay curve of indoor levoglucosan in WUI-fire-affected dust over years has not been characterized in a sustained longitudinal cohort. Spec
- The dust resuspension dynamics that determine inhalation exposure from settled levoglucosan-laden dust have been characterized in laboratory chamber work but not at the residential bedroom scale. Spec
Citations
- Silberstein JM et al. Residual impacts of a wildland urban interface fire on urban particulate matter and dust: a study from the Marshall Fire. Air Quality, Atmosphere & Health. 2023;16:1839-1850. doi:10.1007/s11869-023-01376-3 Peer-reviewed
- Simoneit BRT. Biomass burning — a review of organic tracers for smoke from incomplete combustion. Applied Geochemistry. 2002;17:129-162. doi:10.1016/s0883-2927(01)00061-0 Peer-reviewed
- Vicente ED et al. Impact of wood combustion on indoor air quality. Science of The Total Environment. 2020;705:135769. doi:10.1016/j.scitotenv.2019.135769 Peer-reviewed
- Ward T, Noonan C. Results of a residential indoor PM2.5 sampling program before and after a woodstove changeout. Indoor Air. 2008;18(5):408-415. doi:10.1111/j.1600-0668.2008.00541.x Peer-reviewed
- Hennigan CJ, Sullivan AP, Collett JL, Robinson AL. Levoglucosan stability in biomass burning particles exposed to hydroxyl radicals. Geophysical Research Letters. 2010;37:L09806. doi:10.1029/2010GL043088 Peer-reviewed
- Balogh BS et al. Levoglucosan and Its Isomers as Markers and Biomarkers of Exposure to Wood Burning. Toxics. 2025;13(9):742. doi:10.3390/toxics13090742 Peer-reviewed
- Schauer JJ, Kleeman MJ, Cass GR, Simoneit BRT. Measurement of Emissions from Air Pollution Sources. 3. C₁–C₂₉ Organic Compounds from Fireplace Combustion of Wood. Environmental Science & Technology. 2001;35:1716-1728. doi:10.1021/es001331e Peer-reviewed
- Fine PM, Cass GR, Simoneit BRT. Organic compounds in biomass smoke from residential wood combustion: Emissions characterization at a continental scale. Journal of Geophysical Research: Atmospheres. 2002;107(D21):8349. doi:10.1029/2001jd000661 Peer-reviewed
- Hedberg E, Johansson C, Johansson L, Swietlicki E, Brorström-Lundén E. Is Levoglucosan a Suitable Quantitative Tracer for Wood Burning? Comparison with Receptor Modeling on Trace Elements in Lycksele, Sweden. Journal of the Air & Waste Management Association. 2006;56(12):1669-1678. doi:10.1080/10473289.2006.10464572 Peer-reviewed
- Yan C, Zheng M, Bosch C, Andersson A, Desyaterik Y, Sullivan AP, Collett JL, Zhao B, Wang S, He K, Gustafsson Ö. Residential Coal Combustion as a Source of Levoglucosan in China. Environmental Science & Technology. 2018;52:1665-1674. doi:10.1021/acs.est.7b05858 Peer-reviewed
Frequently asked questions
What is levoglucosan?
Levoglucosan (1,6-anhydro-β-D-glucopyranose, CAS 498-07-7) is a sugar-like molecule produced when cellulose pyrolyzes above ~300°C — the temperature range of wood, vegetation, and biomass combustion. It is the standard molecular tracer for biomass-burning aerosols and indoor dust contamination from wildfire and woodstove sources. It is not itself a hazardous compound; it is the fingerprint that the hazardous mixture (PAHs, fine particulate matter, metals, VOCs) was present.
Is levoglucosan a carcinogen?
No. Levoglucosan is not classified by IARC as a carcinogen and has limited toxicity in its own right. The reason it matters for sleep environment chemistry is not that it harms the sleeper directly but that detecting it in indoor dust documents that hazardous combustion residue — PAHs, fine particulate matter, heavy metals, combustion VOCs — was deposited and is still present.
How long does levoglucosan persist in indoor dust?
Months to years in settled dust. Silberstein et al. 2023 measured indoor dust from homes inside the Marshall Fire perimeter approximately six months after the December 2021 wildfire and found a median levoglucosan concentration of 4,147 ng/g — alongside elevated EPA priority PAHs and metals. The molecular fingerprint was still clearly present, and the dust the family was living in carried the chemical signature of the smoke event.
Why is levoglucosan considered the wood-smoke tracer?
It forms in large quantities specifically during cellulose pyrolysis, which means anything that burns plant material — wildfires, woodstoves, prescribed burns, agricultural waste fires — produces it. The Simoneit 2002 review of organic biomass-burning tracers in Applied Geochemistry establishes it as the most useful single tracer because it is produced abundantly, is reasonably stable in deposited particles, and can be measured at low concentrations using standard analytical chemistry.
Is levoglucosan a perfect source-attribution marker?
No. Yan et al. 2018 in Environmental Science & Technology demonstrated that residential coal combustion in China also emits substantial levoglucosan — meaning the compound is not exclusively a biomass-burning marker in regions where solid-fuel residential heating is common. In North American residential and wildfire contexts the assumption holds well, but the source caveat is worth stating honestly. The reliability of levoglucosan as a quantitative tracer was directly questioned by Hedberg et al. 2006.
Can I measure my own urinary levoglucosan to assess exposure?
Not reliably. The Balogh et al. 2025 review concluded that urinary levoglucosan is not a robust biomarker for personal smoke exposure — it does not consistently track exposure intensity at the individual level, and its pharmacokinetics in humans are not well-characterized. Levoglucosan is a surface and dust tracer, not a body biomarker — a contrast with cotinine for tobacco smoke. For personal smoke-exposure biomarkers, urinary methoxyphenols (see guaiacol) are the better-validated tool.
What does finding levoglucosan in my home tell me?
It documents that biomass-combustion residue is present. Where the residue deposited, the hazardous co-mixture also deposited: PAHs that include the Group 1 carcinogen benzo[a]pyrene, fine particulate matter, combustion VOCs like benzene and formaldehyde, and metals released from burned consumer products in WUI-fire contexts. The actions to take are the same surface-cleaning and bedding-replacement steps documented in The Smoke That Stays for any post-smoke remediation.
Related compounds
This page describes documented chemistry and the source-attribution science. It does not provide medical advice. Anyone concerned about smoke residue in their home should consult professional remediation guidance and their healthcare provider for personal medical decisions.
Last reviewed May 31, 2026.