Indoor environment factor · measured in µg/m³
Limonene
Part of: Terpenes
Also: d-limonene, dipentene, citrus terpene, limonene
The terpene that smells of citrus peel, and the single most abundant fragrance compound in indoor air. It is used in cleaning products, air fresheners and cosmetics, and it reacts with ozone indoors to make compounds that were not in the product.
Where it comes from indoors
Limonene is extracted from citrus peel and used wherever a product needs to smell clean, which is nearly everywhere: surface cleaners, washing-up liquid, polishes, air fresheners, cosmetics. It is also released by wood. In survey after survey it is among the compounds found in almost every dwelling and often the one present at the highest concentration, with peaks that follow cleaning rather than the building.
Its importance is chemical rather than toxicological. Limonene has two double bonds and reacts with ozone within minutes at ordinary indoor concentrations. The products of that reaction include formaldehyde and other aldehydes, hydroxyl radicals that then attack whatever else is present, and secondary organic aerosol — new ultrafine particles formed in the room out of gases.
The practical consequence is that the composition of the air after cleaning is not the composition of the cleaning product.
What the studies report
| Linked to | Effect | Population | Study design | Source | Checked |
|---|---|---|---|---|---|
| — | other 18947 | — · spa treatment room | measurement study in spa salons in Gdynia, Poland: total volatile organic compounds and individual terpenes sampled before, during and after massage treatments, with the applied essential oils recorded | F-1041 Pytel Investigation on air quality of specific indoor environments… (2021) | machine |
| — | ratio 2.02 (1.61–2.55) per a parental history of migration against none ratio of concentrations | children and adolescents aged 3 to 14 years · home | analysis of repeated cross-sectional data from the German Environmental Survey and the KiGGS health survey: benzene, toluene, xylene, limonene and formaldehyde measured in the homes of children and adolescents aged 3 to 14 against equivalized disposable income, socioeconomic status and parental history of migration, in fifteen random-intercept models | F-1085 Indoor air pollution inequalities among children and adolesc… (2025) | machine |
| — | median 15 | — · home | study of Japanese homes: 75 target volatile organic compounds sampled indoors, the samples clustered by their compound composition, and the clusters compared with the symptoms the occupants reported | F-1171 Takaguchi The association between clustering based on composition of v… (2024) | machine |
| Cleaning products | mean 12 | — · personal exposure of the office worker | measurement study of volatile organic compounds in a hotel in the United States: personal samplers worn by room cleaners, housekeepers, office and maintenance workers together with stationary samples in guest rooms, the laundry room, the lobby, the offices and the break room, and the content of the cleaning products themselves | F-1380 Lin et al. Occupational Exposure and Health Risks of Volatile Organic C… (2021) | machine |
| Cleaning products | mean 5.7 | — · personal exposure of the housekeeper | measurement study of volatile organic compounds in a hotel in the United States: personal samplers worn by room cleaners, housekeepers, office and maintenance workers together with stationary samples in guest rooms, the laundry room, the lobby, the offices and the break room, and the content of the cleaning products themselves | F-1381 Lin et al. Occupational Exposure and Health Risks of Volatile Organic C… (2021) | machine |
| Air fresheners | other 159 | — · classroom | measurement campaign in school buildings: volatile organic compounds sampled in 144 school rooms and 35 outdoor locations across conventional, EnergyStar and LEED schools, with walk-through surveys recording the sources present in each room | F-1589 Zhong et al. Volatile Organic Compounds (VOCs) in Conventional and High P… (2017) | machine |
Each row is one Finding — a sentence as printed in one study, recorded with its page in the Coridum Knowledge Base. Follow the Finding number for the exact wording and the citation. Checked says who verified the row: machine means every automatic check passed and the surrounding text was read; person means someone read the sentence in the document. Rows are re-checked by a person over time. The studies are curated in the Coridum Knowledge Base; the reading of them together is a Claim, shown separately.
Identifiers
- Molecular formula
- C₁₀H₁₆
- IUPAC name
- 1-methyl-4-(prop-1-en-2-yl)cyclohex-1-ene
- MeSH
- D000077222
Cite this page
Coridum Research. Limonene. Coridum Knowledge G-0146, 16 September 2026. https://coridum.com/k/G-0146/