Don’t take our word for it. Here’s every fact on this site, with its evidence grade, its caveats, and a link to the source, so you can check us.
We start you on the strong ones: findings that have been replicated or come from one large, well-controlled study. Moderate and weak facts are here too, labeled for what they are. Use “Link to this fact” to share a single card.
Fragrance is everywhere / Measured in people or real products
The more personal care products a woman used, the higher her levels of diethyl phthalate; deodorant (2.8x), nail polish (2.1x) and hair spray (1.8x) users also had higher levels.
Moderate evidence: Cross-sectional association; one urine sample.
Source: Parlett 2013, Journal of Exposure Science and Environmental Epidemiology Link to this fact
Fragrance is everywhere / Measured in people or real products
All five scented personal-care products tested, including a hand lotion and a roll-on deodorant, released terpene fragrance chemicals that react with ozone in indoor air.
Moderate evidence: 5 Swiss grocery-store products; lotion/roll-on emissions measured from a Kimwipe for 1 h, not skin.
Source: Wu 2024, Environmental Science & Technology Letters Link to this fact
Fragrance is everywhere / Measured in people or real products
A silicone ingredient in everyday deodorants, lotions, and hair products (D5) shows up in city outdoor air on a clear morning schedule tracking when people shower and dress for work, peaking around 6-7 AM and fading over the following several hours.
Moderate evidence.
Caveats
Diurnal emission-rate profile derived for one mid-sized US city (Boulder, CO, winter 2015/2017); Toronto ground-site data (2009) show a similarly timed morning peak in concentration, but the emission-rate model itself is Boulder-only.
Source: Coggon 2018, Environmental Science & Technology Link to this fact
Fragrance is everywhere / Measured in people or real products
In a study of 427 people smelling real body-odor samples, individuals stayed identifiable by smell even when wearing a deodorant, but any deodorant (their own or an assigned one) still made people significantly worse at telling them apart than smelling the unfragranced body odor alone.
Moderate evidence.
Caveats
Direct triangle-test design (large for this subfield); deodorants only, not perfumes; public-venue convenience sample; one subgroup (female donor odor + assigned fragrance) fell to chance level.
Source: Allen, Havlíček & Roberts 2015, Frontiers in Psychology Link to this fact
Fragrance is everywhere / Measured in people or real products
People were better at telling two individuals apart when both wore their own habitual deodorant than when both wore an unfamiliar, experimenter-assigned deodorant, consistent with fragrance choice tracking a person's own body chemistry rather than being arbitrary.
Moderate evidence.
Caveats
Own-vs-assigned effect is modest (Exp(B)=1.375, p=0.03); cannot rule out a familiarity confound (using a product you already use vs. a brand-new one) separate from body-chemistry matching.
Source: Allen, Havlíček & Roberts 2015, Frontiers in Psychology Link to this fact
Fragrance is everywhere / Other evidence
In a 36,446-subject Europe/US market-research survey, most people use only one type of deodorant rather than combining formats: 59% used roll-on only, 17% used spray only, and only about 2% used both spray and roll-on deodorant.
Moderate evidence.
Caveats
Deodorant format preference was strongly regional: in the EU roughly 30% used roll-on only and 30% used spray only, while in the US about 80% used a non-spray format and only about 5% used spray only.
Source: Comiskey 2015 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
Fragrance is everywhere / Other evidence
The most common personal-care product combination in this 36,446-subject Europe/US survey was deodorant, oral care, and a shower product used together, at about 19% of subjects; only about 1% of men but about 7% of women used products from all 7 surveyed product categories.
Moderate evidence: This reflects only the 19 personal-care/cosmetic product types surveyed; it says nothing about household, laundry, or air-care product use, which were not included in this study.
Source: Comiskey 2015 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
Fragrance is everywhere / Measured in people or real products
Besides the fragrance-mix allergens, 14 other common fragrance materials (including linalool, benzyl acetate, and hedione) were found in 40-97% of the 73 deodorants tested in 1996; for three of them (hedione, linalyl acetate, alpha-isomethyl ionone) no published human contact-allergy case existed at the time despite their widespread use.
Moderate evidence.
Caveats
Absence of published reports as of 1998 is not the same as absence of risk; testing history for these three substances specifically was not systematically reviewed by the authors beyond a literature check.
Source: Rastogi et al. 1998, Contact Dermatitis Link to this fact
Fragrance is everywhere / Measured in people or real products
Unlike the classic hazardous air pollutants in the same 482-deodorant survey (formaldehyde, benzene, methanol, ethylene oxide, trichloroethylene, chloroform), which each appeared in only 0.4-13.7% of products at generally low concentration, the two intentionally added biocides (chlorine dioxide, silver) and the fragrance allergens were found far more consistently and at far higher concentrations, consistent with the classic HAPs being incidental base-formulation contaminants rather than deliberately added ingredients.
Moderate evidence.
Caveats
An inference from detection-frequency and concentration patterns in one survey, not a source-attribution (chemical-origin) study; the paper itself does not test whether these HAPs come from the base formulation.
Source: Kim et al. 2018, Science of The Total Environment Link to this fact
Fragrance is everywhere / Measured in people or real products
Matching the ingredient lists of 7,603 Korean household chemical products (cleaners, synthetic detergents, fabric softeners, air fresheners, deodorants) against a hormone-disruption hazard database found 293 flagged chemicals, and nearly two out of three products listed more than one of them.
Moderate evidence: Counts ingredient-list matches against EPA ToxCast/CompTox hazard flags, not measured concentrations or confirmed toxicity in the products as sold; single-country database study.
Source: Lee & Ji 2022, Ecotoxicology and Environmental Safety Link to this fact
Fragrance is everywhere / Measured in people or real products
The study's own protocol lists 'hygiene products (e.g., deodorant sprays; aftershave lotions; perfumes; cosmetics; insect repellents)' alongside mouthwash as products that contain or may contain ethanol, and had participants avoid them as confounding ethanol sources.
Moderate evidence: This is a study-design control list, not a measurement of ethanol content or absorption from perfumes/cosmetics specifically.
Source: Reisfield 2021, Journal of Analytical Toxicology Link to this fact
Fragrance is everywhere / Measured in people or real products
Aerosol deodorant/antiperspirant delivers more product per application (mean about 1.27-1.39 g) than roll-on (about 1.0 g) or stick (about 0.6 g) formats, for both French men and women — a pattern relevant to comparing inhalation-relevant exposure across deodorant formats.
Moderate evidence.
Source: Ficheux et al. 2016 (amount data), Food and Chemical Toxicology Link to this fact
Information, not medical advice. See also: myths we won’t tell you.