Every fact on this site, with its evidence grade, its caveats and a link to the source.
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.
Laws and loopholes / Review of other studies
As of 2008, no US federal law required companies to list all the chemicals in a consumer product or in its fragrance; air fresheners and laundry products did not even have to say they contained fragrance.
Strong evidence.
Caveats
US law as of 2008; MoCRA (2022) later required FDA-designated fragrance-allergen labeling for cosmetics only (rule pending at enactment); household products still uncovered for cosmetics.
Source: Steinemann 2009, Environmental Impact Assessment Review Link to this fact
Laws and loopholes / Government agency
The 2022 US cosmetics law does not cover air fresheners, cleaning products or laundry products at all.
Strong evidence: MoCRA amends the FFDCA cosmetics chapter only; household products fall under CPSC/EPA law.
Source: MoCRA 2022 Link to this fact
Laws and loopholes / Government agency
FDA names laundry detergents, fabric softeners, dryer sheets, and room and carpet fresheners as fragranced products that fall under the Consumer Product Safety Commission rather than FDA cosmetics regulation.
Strong evidence: Statement of jurisdiction only; says nothing about what CPSC does or does not require of these products.
Source: FDA 2026 (Fragrances in Cosmetics) Link to this fact
Children and pregnancy / Measured in people or real products
Mothers who used perfumed laundry detergent had significantly higher levels of the musk chemical tonalide (AHTN) in their breast milk than mothers who used unscented detergent.
Moderate evidence: Product-use data from a N=44 subset; cross-sectional association, not an intervention; adjusted for sampling year.
Source: Lignell 2008, Environmental Science & Technology Link to this fact
Fragrance is everywhere / Measured in people or real products
A lab analysis of 59 soaps, surface cleaners, laundry and dish-washing products from four European countries found the citrus-scent chemical limonene in 78% of them, linalool in 61% and citronellol in 47%; all three are fragrance chemicals linked to skin allergy.
Moderate evidence: Products c. 2000, EU only; parent terpenes measured, not the allergenic oxidized forms; Unilever co-author.
Source: Rastogi 2001, Contact Dermatitis Industry-funded Link to this fact
Fragrance is everywhere / Measured in people or real products
In a test of 59 best-selling Korean household products, the citrus-scent chemical limonene was the chemical most often given off: it came from 44% of products, including bleach, dish soap, laundry detergent, disinfectant and even a liquid pesticide.
Moderate evidence: Heated headspace, library-match ID, presence not exposure.
Source: Kwon 2007, Journal of Hazardous Materials Link to this fact
Fragrance is everywhere / Measured in people or real products
Tumble drying real household laundry released 256-342 milligrams of textile microfiber per kilogram of fabric dried, whether the dryer vented outdoors or condensed the moisture indoors, a similar order of magnitude to what washing machines release.
Moderate evidence: One UK lab, one detergent, one condenser model and one vented model, n=8 real loads per dryer type; measures plain cotton/polyester fiber, not fragrance or VOCs.
Source: Cummins 2023, PLOS ONE Industry-funded Link to this fact
Green, natural and unscented / Government agency
Health Canada's cosmetic labeling guidance on 'unscented'/'fragrance-free' does not cover laundry detergent, fabric softener or dryer sheets; Canada's legal definition of 'cosmetic' (Food and Drugs Act s.2) covers products for the complexion, skin, hair or teeth, not fabric.
Moderate evidence.
Caveats
The 'cosmetic' definition and its exclusion of fabric-care products is confirmed directly from the source text; that laundry products instead fall under Canada's consumer chemical product safety rules (CCPSA) is background knowledge, not itself stated in either captured Health Canada page, so graded moderate rather than strong.
Source: Health Canada 2026 Link to this fact
Health effects / Self-reported survey
Among adults with a diagnosis of autism or autism spectrum disorder, 71.4% (US) and 51.2% (Australia) report health problems from the scent of laundry products coming from a dryer vent — the highest prevalence of any group measured (general population, asthmatics, autistic adults, migraineurs) in either country.
Moderate evidence.
Caveats
These country-specific figures are restated from Steinemann's 2018 autistic-adults survey, which this evidence base has not yet independently ingested and read in full; the primary's own main-text tables report only a pooled 3-country figure (57.5%) for this specific exposure item, so the US/AU split has not been directly verified against the primary's own tables here (only checked for internal arithmetic consistency).
Source: Goodman, Nematollahi & Steinemann 2020/2021, Air Quality, Atmosphere & Health Link to this fact
Health effects / Self-reported survey
Among people who get migraines, 40.8% (US) and 29.1% (Australia) report health problems from the scent of laundry products coming from a dryer vent, with asthma attacks the most frequently reported effect in this group.
Moderate evidence.
Caveats
Restated from Steinemann & Nematollahi's 2020 migraine survey, which this evidence base has not yet independently ingested; self-report only, no clinical migraine diagnosis confirmation described in this source.
Source: Goodman, Nematollahi & Steinemann 2020/2021, Air Quality, Atmosphere & Health Link to this fact
Hidden ingredients / Measured in people or real products
In a test of 6 best-selling US air fresheners and laundry products, researchers found 98 chemical detections (58 different chemicals) released into the air; none appeared on any product label, and only 1 (ethanol) appeared on a safety data sheet.
Moderate evidence: N=6 products, headspace only, semi-quantitative.
Source: Steinemann 2009, Environmental Impact Assessment Review Link to this fact
Hidden ingredients / Measured in people or real products
When researchers tested 25 best-selling US laundry, cleaning, personal-care and air-freshener products, they found 133 different chemicals released into the air, but only 1 of them was listed on any product label.
Moderate evidence: Single headspace sample per product; VOC counts depend on detection threshold.
Source: Steinemann 2011, Environmental Impact Assessment Review Link to this fact
Hidden ingredients / Measured in people or real products
The best-selling US laundry detergent's label and safety sheet disclosed almost none of what it released; only ethanol was listed.
Moderate evidence: Same detergent measured in 2009, 2011 and 2013 papers; count once.
Source: Steinemann 2013, Air Quality, Atmosphere & Health Link to this fact
Indoor air / Measured in people or real products
Scented laundry products put fragrance chemicals into outdoor air: in two homes, limonene (a citrus scent chemical) came out of the dryer vent only when fragranced detergent or dryer sheets were used (up to 14.7 ug/m3), not in the no-product runs.
Moderate evidence.
Caveats
2 homes (Steinemann 2013), single grab samples; undiluted vent air, not a breathing-zone dose. Replicated at much higher magnitude and with a dose-response signal by Goodman et al. 2019 (6 Melbourne homes, before/after switch design): fragranced-detergent vent D-limonene 2.35-118 ug/m3 vs 0.24-0.26 ug/m3 in fragrance-free-only homes, and switching from fragranced to fragrance-free detergent cut vent D-limonene by up to 99.7% (mean 79.1%) within a month. The two studies share one author (Anne Steinemann) and neither ran statistical significance tests, so the combined evidence (8 homes total) stays below strong, but the qualitative and dose-response finding is now cross-country replicated within one research program rather than resting on a single 2-home study.
Source: Steinemann 2013, Air Quality, Atmosphere & Health Link to this fact
Indoor air / Measured in people or real products
Dryer-vent air carried far more of the citrus-scent chemical D-limonene when households used fragranced laundry detergent (2.35-118 ug/m3, mean 33.34) than when they used fragrance-free detergent (0.13-1.50 ug/m3 after switching; 0.24-0.26 ug/m3 in households that never used fragranced detergent).
Moderate evidence.
Caveats
6 Melbourne-area homes, D-limonene only (not the fuller VOC/HAP panel), no statistical significance testing; shares one author (Anne Steinemann) with the earlier 2-home study it builds on, so not a fully independent replication.
Source: Goodman 2019, Air Quality, Atmosphere & Health Link to this fact
Indoor air / Measured in people or real products
Switching to fragrance-free laundry detergent also reduced D-limonene in the laundry room's own indoor air, not just at the dryer vent, by up to 72.7% (mean 45.8%) within one month.
Moderate evidence: 4 households, single background-air sample per round, no statistical testing.
Source: Goodman 2019, Air Quality, Atmosphere & Health Link to this fact
Indoor air / Measured in people or real products
Every one of 25 fragranced laundry products tested (US and Australian detergents and dryer sheets) emitted a terpene fragrance chemical (such as limonene, alpha-pinene or eucalyptol), while none of 10 fragrance-free laundry products emitted any terpene at all.
Moderate evidence.
Caveats
This paper restates chemical-panel data from Steinemann 2015 and Nematollahi 2018/2019, which are not yet independently checked in this evidence base; treat the 100%-vs-0% split as a secondary report until those primaries are read directly.
Source: Goodman, Nematollahi & Steinemann 2020/2021, Air Quality, Atmosphere & Health Link to this fact
The industry / Industry source
Even after this 2017 update, the fragrance industry's own aggregate exposure model still explicitly excluded household cleaning and laundry products — the product category the industry's own 2003 safety-process paper says accounts for about 60% of fragrance volume — and named their inclusion as future work.
Moderate evidence.
Caveats
Single industry methods paper describing its own model's scope; the gap was closed industry-wide only in a later 2024 paper (Lee et al.), which this claim's caveat should be read alongside.
Source: Comiskey 2017 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
Skin allergy / Measured in people or real products
Among all detergent types studied, laundry (textile) detergents had both the highest share of products naming a fragrance allergen (50.0% of 270 products) and the highest average number of named allergens per product (1.7) — ahead of dish soap, glass cleaner, toilet cleaner, and dishwasher detergent.
Moderate evidence: Named-on-label only, not measured concentration or skin dose; German 2015 sample.
Source: Wieck 2018, Regulatory Toxicology and Pharmacology Link to this fact
What you can do / Review of other studies
Fragrance-free cosmetics and laundry products cut the main routes by which synthetic musks enter the body: skin contact and washed clothing.
Moderate evidence.
Caveats
Route inferred from exposure data; no intervention study of musk body burden. Hutter 2009 (100 Vienna adults) gives cross-sectional human support for the polycyclic musks specifically: monthly-frequency of body lotion and perfume use significantly predicted blood galaxolide/tonalide (beta=0.188-0.192, p<0.05); no cosmetics-use variable predicted nitro-musk (musk ketone/musk xylene) blood levels there. Lignell 2008 (101 Swedish mothers, milk 1996-2003) gives a second, milk-matched confirmation with per-product specificity: perfume use predicted HHCB and perfumed-laundry-detergent use predicted AHTN, but musk xylene showed no association with any product category tested. Still no before/after intervention trial for any musk, and the nitro-musk part of the action's benefit remains unverified in two independent studies now.
Source: Schmeiser 2001, International Journal of Hygiene and Environmental Health Link to this fact
What you can do / Measured in people or real products
Musk levels in blood and milk seem to track current personal-care product use rather than lifetime storage: Hutter 2009 found that how often people used perfume and body lotion significantly predicted their blood levels of the polycyclic musks (galaxolide, tonalide) in 100 adults, so choosing fragrance-free personal care and laundry products during pregnancy and breastfeeding is a plausible way to lower a mother's musk levels and, in turn, transfer to the baby.
Moderate evidence.
Caveats
Route inferred in Reiner 2007 from the absence of an age trend in milk, and now supported by direct product-use data in two independent populations and matrices: Hutter 2009 (blood, non-pregnant Vienna adults) and Lignell 2008 (101 Swedish mothers, milk itself — the exact matrix this claim concerns). Lignell 2008 found perfume-use frequency predicted HHCB and perfumed-laundry-detergent use predicted AHTN in milk, but no product-use variable predicted musk xylene, matching Hutter's blood-based polycyclic/nitro split. Still correlational and cross-sectional; no study has measured milk musk levels before and after a change in a mother's product use, and no cosmetics-use variable has ever predicted a nitro musk in either study.
Source: Reiner 2007, Environmental Science & Technology Link to this fact
What you can do / Self-reported survey
Fragrance-free policies need to cover cleaning and laundry products, not just perfume: of 60 people who react to fragranced products, 50 named cleaning products, 47 perfume and 41 laundry products as persistent triggers.
Moderate evidence: Self-selected Canadian sample (90% female); counts of participants naming a source, not exposure measurements.
Source: Roy 2026 Link to this fact
What you can do / Review of other studies
For fragrance-allergic people, dermatologists recommend removing diffusers, scented candles, room deodorizers, incense and wax melts, switching household cleaners, wipes and laundry products to fragrance-free, and bringing your own shampoo to the salon and your own oil to massages.
Moderate evidence: Expert advice; the salon point rests on a single exposure keeping skin flared up to ~4 weeks (clinical observation).
What you can do / Self-reported survey
Fragrance-free health-care policies should cover cleaning and laundry products, not just staff perfume; Canadian advocates ask for exactly this, and people who react name cleaning products as their most common trigger (50 of 60).
Moderate evidence: Advocacy position plus a self-selected focus-group sample; no evidence yet that policies reduce exposure or symptoms.
What you can do / Measured in people or real products
Because galaxolide (HHCB) levels in milk tracked perfume use and tonalide (AHTN) levels tracked scented-laundry-detergent use specifically, choosing fragrance-free perfume and fragrance-free laundry detergent during pregnancy and breastfeeding are each independently plausible ways to lower the corresponding musk chemical passed to a nursing infant.
Moderate evidence.
Caveats
Correlational and cross-sectional, no before/after intervention trial; musk xylene (a nitro musk) showed no association with any product category tested, so this action would not address that compound.
Source: Lignell 2008, Environmental Science & Technology Link to this fact
What you can do / Measured in people or real products
Switching from a fragranced to a fragrance-free laundry detergent cut the fragrance chemical D-limonene coming out of the dryer vent by up to 99.7% (mean 79.1%) within one month, in real households, with no extra cost or apparent inconvenience.
Moderate evidence.
Caveats
4 households switched, D-limonene only; one household's no-product baseline (machine run with no detergent) actually rose 70.3% after the switch, which the paper attributes to residual fragrance chemicals left in the machine or clothing; no statistical testing.
Source: Goodman 2019, Air Quality, Atmosphere & Health Link to this fact
Health effects / Review of other studies
No published study has been found that tests whether quaternary ammonium compounds specifically from laundry fabric softeners or dryer sheets, as opposed to disinfectant or cosmetic-preservative exposure, cause asthma or skin sensitization in consumers.
Weak evidence: This is an evidence-gap statement, not a positive finding; the review also never discusses esterquats, the ester-linked chemistry that dominates modern fabric softeners, at all.
Source: Peyneau 2022, Frontiers in Toxicology Link to this fact
What you can do / Review of other studies
If households switch from fragranced to fragrance-free laundry detergent, modeling suggests dryer-vent limonene emissions across a whole city or state could drop substantially — an estimated 1.58 tons per year for metropolitan Melbourne, or 8.66 tons per year for the state of California.
Weak evidence.
Caveats
This is a modeled extrapolation, not a measurement: it multiplies a mean vent concentration from just 2-6 households (one grab sample each) by census household counts and usage-rate assumptions, with no confidence interval or sensitivity analysis anywhere in the calculation; the Melbourne input is dominated by a single outlier household roughly 11 times the other three.
Source: Goodman, Nematollahi & Steinemann 2020/2021, Air Quality, Atmosphere & Health Link to this fact
Information, not medical advice. See also: myths we won’t tell you.