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.
Children and pregnancy / Measured in people or real products
In 34 California childcare centers, the chemicals at the highest levels in the air children breathed came from cleaning and personal-care products: a silicone ingredient called D5 (median 51 µg/m³) and the citrus-scent chemical limonene (median 33 µg/m³).
Strong evidence: Single-day samples; upper values capped by calibration (underestimates).
Children and pregnancy / Review of other studies
Children exposed to household chemical/cleaning products before birth or in their first year wheeze more often, now replicated in four independent prospective birth cohorts. The founding ALSPAC cohort (UK, n=7,019, Sherriff et al. 2005) found that an 11-product, frequency-weighted prenatal household chemical (TCB) score was significantly associated with persistent wheeze through 3.5 years (adjusted OR 1.06 per unit increase; top-vs-bottom-decile adjusted OR 2.3), but not with transient early or late-onset wheeze; this is the same ALSPAC cohort and composite-score methodology that both Casas 2013 and Mikeš 2019 name as their model. In the Canadian CHILD cohort (n=2,022), frequent use in early infancy was linked to higher odds of recurrent wheeze (adjusted OR 1.35) and asthma diagnosis (adjusted OR 1.37) by age 3, but not isolated skin-prick allergy (adjusted OR 1.14, ns), though wheeze combined with allergy was itself raised (adjusted OR 1.49). In the Czech ELSPAC-CZ cohort (n=3,411), each 1-SD increase in an 18-product household chemical exposure score at 6 months raised the odds of intermediate-onset transient, intermediate-onset persistent, and early-onset persistent wheeze phenotypes through age 5 (adjusted OR 1.23-1.36), and those persistent phenotypes carried 5-8x higher odds of doctor-diagnosed asthma at age 7 (pediatrician records, not self-report). In the pooled Spanish INMA cohorts (n=2,292), prenatal (third-trimester) use of cleaning sprays raised the odds of both wheezing (OR 1.37) and lower respiratory tract infection (OR 1.29) in the first year of life, with solvents raising wheezing odds (OR 1.30) and air fresheners raising LRTI odds (OR 1.29); bleach, ammonia, and non-spray cleaners showed no association.
Strong evidence.
Caveats
All four cohorts are observational and use self-reported product-use frequency, not measured indoor air chemistry. The ALSPAC/Sherriff 2005 and ELSPAC-CZ signals are specific to persistent-type wheeze phenotypes, not wheeze in general; ALSPAC found no association with transient early or late-onset wheeze. The 'not atopy' finding remains single-cohort (CHILD only); ELSPAC-CZ's atopic-rash variable is a covariate, not an outcome, and Casas 2013 measured neither atopy nor a physician asthma diagnosis, only maternal-reported LRTI and any-wheezing through 12-18 months, so it neither confirms nor refutes the atopy finding; ALSPAC/Sherriff 2005 did not assess atopy or asthma at all. Casas 2013 is the only cohort among the three post-2010 cohorts with genuinely prenatal (rather than early-postnatal) exposure measurement, but ALSPAC/Sherriff 2005 is also prenatal and its composite score behaved like CHILD's and ELSPAC-CZ's (significant), not like Casas's (null) — evidence against prenatal timing per se explaining the Casas null. Casas 2013's own summed cleaning-product-count score was NOT a significant predictor, unlike ALSPAC's, CHILD's, and ELSPAC-CZ's frequency-weighted composite scores — an open methodological tension (register entry C262) that means 'more products used' is not yet a uniformly replicated exposure metric across all cohorts, even though several specific products (sprays consistently, plus solvents and air fresheners) are.
Source: Salonen 2024, Environment International Link to this fact
Children and pregnancy / Measured in people or real products
In a national Canadian birth cohort (n=2,022), infants in homes with more frequent use of household cleaning products at 3–4 months of age had higher odds of recurrent wheeze (adjusted OR 1.35 per interquartile increase in use) and of an asthma diagnosis (adjusted OR 1.37) by age 3, but no higher odds of isolated allergic sensitization (skin-prick positivity).
Strong evidence.
Caveats
Observational; the authors explicitly state their results do not prove causation. Recurrent wheeze combined with atopy was itself significantly increased (adjusted OR 1.49), so isolated atopy — not allergic sensitization in general — is what showed no association.
Source: Parks et al. 2020, CMAJ (Canadian Medical Association Journal) Link to this fact
Green, natural and unscented / Other evidence
EWG Verified does not mean fragrance-free: fragranced cleaners can be licensed with fragrance up to 1 percent of the formula.
Strong evidence: Pet grooming products are limited to an EWG 'acceptable fragrance list' not reproduced in the document.
Source: EWG Verified criteria for cleaning products (10.24), Environmental Working Group, 2024 Link to this fact
Hidden ingredients / Other evidence
For EWG Verified cleaners whose fragrance has more than five ingredients, the package may show only 'fragrance*' plus the first five; the full list is online.
Strong evidence: Describes the rule as written; no data on how many licensed products use the shortened form.
Source: EWG Verified criteria for cleaning products (10.24), Environmental Working Group, 2024 Link to this fact
Indoor air / Review of other studies
A chemical released indoors is roughly 1,000 times more likely to be breathed in than the same amount released outdoors (exact when comparing the low end of each range; only ~100x at the high end, since the ranges overlap at 10⁻³), so cleaning products and air fresheners (about 1% of California's smog-forming emissions) may deliver an inhaled dose on the same scale as all outdoor sources combined.
Strong evidence.
Caveats
Modeled population intake fractions (not measurements), population-average estimate. Traced to the primary source, Lai, Thatcher & Nazaroff 2000 (JAWMA 50:1688-1699), which derives outdoor PITF 10⁻⁶-10⁻³ vs indoor/in-vehicle PITF 10⁻³-10⁻¹ from Gaussian-plume and mass-balance modeling (Nazaroff co-author of both papers, so this is not independent replication). The ranges overlap at 10⁻³, so '1000x' is a floor-to-floor comparison, not a fixed multiplier under all conditions.
Source: Nazaroff & Weschler 2004, Atmospheric Environment Link to this fact
Indoor air / Review of other studies
Scent chemicals such as limonene and pine oil react with ozone indoors to make new pollutants, including formaldehyde and fine particles, that keep forming for hours after cleaning ends.
Strong evidence: Size of the effect depends on dose and indoor ozone; confirmed by later chamber and field studies.
Source: Nazaroff & Weschler 2004, Atmospheric Environment Link to this fact
Indoor air / Measured in people or real products
Questionnaires about habits and routines correctly sorted only 20% of people by their measured exposure to cleaning and fragrance chemicals, vs 61% for traffic fumes; exposure depends on individual behavior and product choice.
Strong evidence.
Caveats
'Product choice' is the authors' explanation, not directly tested in this paper; independently corroborated by a larger, more direct 2021 UK study (Heeley-Hill 2021, 60 homes, daily diary-logged — not recalled — product-use frequency vs measured concentrations) that found cumulative product-use frequency has essentially no predictive power for measured indoor VOC concentrations (R²<0.001 for total VOC; no individual VOC significant).
Source: Edwards 2006, Atmospheric Environment Industry-funded Link to this fact
Indoor air / Measured in people or real products
In week-long air measurements across 11 European cities, the scent chemicals limonene and alpha-pinene were the compounds most concentrated in homes compared with workplaces (about 4x), attributed to perfumes, cleaning and fragranced products.
Strong evidence: Source attribution by the authors, not measured per product.
Source: Geiss 2011, Atmospheric Environment Link to this fact
Indoor air / Measured in people or real products
Scent-type chemicals typical of fragranced and cleaning products (limonene, pinene, carene) were the signature of home air: close to zero outdoors but tens to hundreds of times higher inside homes.
Strong evidence.
Caveats
Small original study (n=7); the indoor-source signature (not the specific product-category attribution) is now independently replicated by a much larger 2021 UK study with real paired outdoor sampling (Heeley-Hill 2021, 60 homes: limonene indoor:outdoor ~19x, alpha-pinene ~10x), though that larger study also found cumulative product-use frequency does not predict concentration (only insecticide/plug-in-air-freshener use showed weak covariance with limonene) — so the indoor-source signature is strong, the specific 'cleaning products' attribution stays inferential. Givaudan-funded (COI); analysis independent.
Source: Gokhale 2008, Science of the Total Environment Link to this fact
The industry / Other evidence
EWG Verified is a licensing program in which EWG writes the criteria, scores the products, pre-approves the mark's use in marketing, and can bar claims that 'would harm or discredit EWG'.
Strong evidence: EWG is an advocacy nonprofit, not an industry body, but it is an interested party acting as standard-setter, certifier and publisher.
Source: EWG Verified criteria for cleaning products (10.24), Environmental Working Group, 2024 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 / Other evidence
FDA's food allergen labeling law explicitly does not apply to cosmetics, drugs, or household cleaning products, so fragrance allergens in those products have no allergen-naming duty under it.
Strong evidence: Says nothing about the separate MoCRA fragrance-allergen rulemaking, which is still pending.
Source: FDA food allergen Q&A Ed. 5 (2025), FDA guidance for industry (Docket FDA-2022-D-0099) Link to this fact
Laws and loopholes / Other evidence
OSHA lists perfumes and colognes, cleaning products, pesticides and personal-care products among sources of workplace indoor air pollutants, but sets no limit or rule for any of them.
Strong evidence: Mentions are brief source lists; fragrance is not named as a category, and no health data are given.
Source: OSHA 3430-04, 2011 Link to this fact
Skin allergy / Measured in people or real products
In a clinical study of 658 hand-eczema patients across 3 European centers, 67 (10.2%) reacted on patch testing to at least one fragrance chemical selected because it is common in household cleaning and personal-care products used on the hands.
Strong evidence: Clinic-referred hand-eczema population (3 tertiary centers), not a random sample of the general public.
Source: Heydorn 2003, Contact Dermatitis Industry-funded Link to this fact
What you can do / Government agency
EPA says to never mix chlorine bleach solution with other cleaning solutions or detergents that contain ammonia, because toxic fumes could be produced.
Strong evidence: Well-established chemistry (chloramine gas formation); stated here as a direct safety instruction, not a study finding.
Source: US EPA, "A Brief Guide to Mold, Moisture and Your Home" Link to this fact
What you can do / Other evidence
EWG will not license air fresheners, candles, plug-in or timed-release odor products, or liquid laundry and dishwasher pods, so an EWG Verified mark will not be found on those product types.
Strong evidence: Reflects the 10.24 criteria; EWG may change categories, and unlicensed products are not necessarily worse.
Source: EWG Verified criteria for cleaning products (10.24), Environmental Working Group, 2024 Link to this fact
Children and pregnancy / Measured in people or real products
Childcare air had about three times more limonene than new California homes (33 vs 11 µg/m³), which the authors link to frequent cleaning.
Moderate evidence: Comparison with a different study (Offermann 2009); daytime vs 24-h sampling.
Children and pregnancy / Self-reported survey
Mothers who use cleaning sprays during pregnancy have infants with higher odds of both a lower respiratory tract infection (29% higher, OR 1.29) and wheezing (37% higher, OR 1.37) in their first year of life, in a pooled analysis of four Spanish birth cohorts (n=2,292); prenatal solvent use also raised wheezing odds (30% higher) and prenatal air freshener use raised LRTI odds (29% higher).
Moderate evidence.
Caveats
Single research group/dataset (pooled INMA cohorts, all Spanish, one study design), self-reported exposure and outcome by mothers, and only 12-18 month follow-up (no atopy or physician-diagnosed asthma measured). Consistent in direction with two other independent cohorts (Parks 2020, Canada; Mikeš 2019, Czech Republic) that measured early-postnatal rather than prenatal exposure, which is why the combined three-cohort claim is graded strong elsewhere while this single-paper prenatal-specific finding stays moderate.
Source: Casas 2013, International Journal of Public Health Industry-funded Link to this fact
Children and pregnancy / Self-reported survey
In a random sample of Swedish teenagers aged 13-19, about 1 in 6 (15.6%) said they were bothered by strong odors such as perfume, cleaning agents, or flower scents, most often affecting the nose.
Moderate evidence: Single-item self-report; general odor sensitivity, not fragranced-product-specific; one Swedish town.
Source: Andersson 2008, International Journal of Hygiene and Environmental Health Link to this fact
Children and pregnancy / Measured in people or real products
The protective association between bleach cleaning and reduced allergy/asthma risk was abolished in households with parental smoking; in that subgroup, bleach use was instead linked to a higher rate of recurrent bronchitis (adjusted OR for the smoking-by-bleach interaction, 2.03, 95% CI 1.12-3.66).
Moderate evidence: Subgroup/interaction analysis from a single cross-sectional study; the recurrent-bronchitis outcome is parent-reported, not medically confirmed.
Source: Nickmilder, Carbonnelle & Bernard 2007, Pediatric Allergy and Immunology Link to this fact
Children and pregnancy / Self-reported survey
In a Dutch birth cohort of 2,333 adolescents (age 14), a composite score for household use of 10 types of cleaning agents was not associated with asthma, rhinitis, or eczema, even at the highest exposure quartile: adjusted OR (95% CI) 0.95 (0.56, 1.63) for asthma, 1.23 (0.83, 1.82) for rhinitis, and 0.95 (0.56, 1.63) for eczema, comparing highest to never/seldom use.
Moderate evidence.
Caveats
Cross-sectional, single cohort, parent-reported exposure and outcomes; adolescents are not the ones doing the cleaning, so this speaks to a low-exposure life stage rather than ruling out effects at higher exposure (e.g. prenatal/infancy).
Source: Bukalasa et al. 2019, Environment International Link to this fact
Children and pregnancy / Self-reported survey
A sensitivity analysis restricted to the 988 adolescents (42% of the cohort) reported to be sometimes or mostly present at home during cleaning activities again found no association between the composite cleaning-agent-use score and asthma, rhinitis, or eczema, confirming the main null result.
Moderate evidence.
Caveats
Smaller subsample (n≈988) with wider confidence intervals; one rhinitis point estimate for the low-exposure category rose to adjusted OR 2.14 (95% CI 1.04, 4.41) without a dose-response pattern across categories, which the authors do not treat as a real effect.
Source: Bukalasa et al. 2019, Environment International Link to this fact
Fragrance is everywhere / Review of other studies
In California's 1997 inventory, air fresheners were the single largest category of cleaning-product chemical emissions: 7.5 metric tons a day, just ahead of general-purpose cleaners.
Moderate evidence: 1997 sales-based inventory; later SoCAB inventory had air fresheners <2.5 t/d.
Source: Nazaroff & Weschler 2004, Atmospheric Environment Link to this fact
Fragrance is everywhere / Measured in people or real products
Scented product categories (personal care and cleaning) made about half of the ozone from consumer and industrial chemical products in New York, mostly through their alcohol and glycol solvents rather than the fragrance molecules.
Moderate evidence: Box-model budget, one city/episode; 'fragranced VCP' is a product category: fragrance compounds are ~6% of VCP ozone, oxygenates 24%, and ethanol 15%.
Source: Coggon 2021 Link to this fact
Fragrance is everywhere / Self-reported survey
In a 1995 population-based telephone survey of 4,046 California adults, 15.9% said they were 'allergic or unusually sensitive to everyday chemicals' (like cleaning supplies, paints, perfumes, or soaps) and 6.3% reported a doctor's diagnosis of environmental illness or multiple chemical sensitivity.
Moderate evidence.
Caveats
Self-report only, no clinical verification of diagnosis or symptoms; California-specific, not national; the study's own authors take no position on whether this reflects a real physiologic condition or societal apprehension about chemicals.
Source: Kreutzer, Neutra & Lashuay 1999, American Journal of Epidemiology Link to this fact
Fragrance is everywhere / Other evidence
In a 2016 barcode-scan inventory of 2,963 household products from 131 German homes, EU-regulated biocidal active substances (preservatives, disinfectants, insecticides, repellents) were found in every single household, and personal care products plus washing/cleaning agents accounted for 90% of all such ingredient observations, far outnumbering the biocidal products the regulation is actually built around.
Moderate evidence.
Caveats
German sample; convenience sampling in 2 of 3 neighborhoods (response rate not calculable there); 65% response rate in the rural site; ingredient-list presence, not measured wastewater concentration or biological exposure.
Source: Wieck 2016, Environment International Link to this fact
Fragrance is everywhere / Other evidence
Researchers found multiple fragrance sources (cosmetics, air fresheners, cleaning/laundry products, fragrance-emitting devices, or candles) in every one of the 37 homes they surveyed for a chemical-intolerance study.
Moderate evidence.
Caveats
Sample is self-selected chemical-intolerance patients recruited from a specialty clinic, not a general-population sample; fragrance ubiquity may be overrepresented relative to the general population's home inventories.
Source: Rincón et al. 2024, Primary Health Care Research & Development Link to this fact
Fragrance is everywhere / Other evidence
Perchloroethylene in Suffolk County groundwater: not detected in about 92% of supply wells sampled 2009-2013, but found in three times as many wells in 2013 as in 1987 with the average concentration doubled; public-supply maximum 93 ppb against a 5 ppb limit, and orders of magnitude higher at dry-cleaning sites.
Moderate evidence: Local county data summarized second-hand; trend reflects the wells sampled and is not attributed to dry cleaning alone.
Source: SCDHS 2018 Link to this fact
Green, natural and unscented / Journalism
Green-claim auditors named 'all-natural' as a textbook example of a vague green claim and called household cleaning-product makers 'among the worst greenwash offenders'.
Moderate evidence: Opinion of TerraChoice staff; '3 of 397 cleaners' figure not text-verified.
Source: Dahl 2010, Environmental Health Perspectives Link to this fact
Green, natural and unscented / Measured in people or real products
In a chamber test of 30 US cleaning products and air fresheners, fragrance-free green cleaners gave off significantly fewer volatile chemicals than conventional ones: about 500 vs 4,700 ug/m3 total on average (approx., read from Fig. 4A), and about 6 vs 46 distinct VOCs per product (approx., read from Fig. 4D).
Moderate evidence.
Caveats
EWG-authored (advocacy nonprofit that ranks cleaners and licenses EWG VERIFIED to cleaner makers); Skyline Foundation grant; unblinded; 7 fragrance-free vs 14 conventional products, one product per brand, single lab; green products also applied less product per use; chamber concentration, not personal exposure. Group means are read from Fig. 4.
Health effects / Review of other studies
Cleaning products were the suspected exposure in 236 of 1,915 (12%) confirmed work-related asthma cases across California, Massachusetts, Michigan, and New Jersey (1993-1997); in California, janitors and cleaners had roughly double the confirmed-case rate of all other occupations combined (4.3 vs 2.3 per 100,000 workers).
Moderate evidence.
Caveats
Now traced to its primary source (Rosenman 2003), not a secondary citation. But the underlying surveillance system's own authors say it misses 53-87% of true cases (Michigan capture-recapture) and that up to 37% of confirmed cases in such systems may not be truly work-related (Malo et al., cited by Rosenman); 'cleaning products' is a broad, mostly unspecified chemical category (36% of named agents never identified further than 'cleaning compound'), not fragrance-specific (limonene only 2/300 exposure counts).
Source: Nazaroff & Weschler 2004, Atmospheric Environment Link to this fact
Health effects / Measured in people or real products
In a Toronto clinic for work-related breathing problems, about 1 in 10 referred workers had an irritable larynx (throat) syndrome rather than asthma; perfumes and cleaning agents, bleaches and air fresheners were among the named triggers.
Moderate evidence.
Caveats
Single referral clinic, retrospective, n=30; perfume named by 5/30 and cleaning agents/fresheners by 4/30; 10% of referrals, not of workers. Morrison 1999, the founding case series behind the diagnostic criteria Hoy applied, independently found perfume was a named trigger in only 26% (10/39) of its own ILS cohort, behind reflux (72%) and other airborne irritants (51%) — the syndrome is not fragrance-specific at its point of origin either.
Health effects / Self-reported survey
In the same 2016 US survey, about 1 in 4 adults (25.9%) said they were unusually sensitive to everyday chemicals such as cleaning products, perfume, and detergents, and 81% of them reported health problems from fragranced products.
Moderate evidence: Self-report; adults 18-65 in an opt-in online panel; earlier US telephone surveys gave 11-16%.
Source: Steinemann 2018 (JOEM), Journal of Occupational and Environmental Medicine Link to this fact
Health effects / Measured in people or real products
Cleaning products were the suspected exposure in 236 of 1,915 (12%) confirmed work-related asthma cases across California, Massachusetts, Michigan, and New Jersey, 1993-1997; most were new-onset asthma (80%) and about a fifth were consistent with reactive airways dysfunction syndrome, an irritant-induced, non-allergic asthma type.
Moderate evidence.
Caveats
This is a primary surveillance source, not a population prevalence estimate: the authors' own capture-recapture analysis found the surveillance system misses 53-87% of true work-related asthma cases in Michigan, and up to 37% of confirmed cases in such systems may not be truly work-related (Malo et al., cited by the authors). Fragrance/limonene was a minor named agent (2 of 300 exposure counts); bleach, acids, disinfectants, and quaternary ammonium compounds dominate.
Source: Rosenman 2003, Journal of Occupational and Environmental Medicine Link to this fact
Health effects / Self-reported survey
In a large random sample of Swedish adults (Vasterbotten, n=3,406), 12.2% said they get symptoms from odorous or pungent chemicals such as perfumes and cleaning agents in doses that don't bother most other people, but only 3.3% had actually been given a doctor's diagnosis of a chemical-intolerance condition.
Moderate evidence: Single region (Vasterbotten county), not national; diagnosis status is itself self-reported, not verified against medical records.
Source: Palmquist 2014, International Journal of Hygiene and Environmental Health Link to this fact
Health effects / Self-reported survey
In a 2002-03 US national telephone survey of 1,054 randomly selected adults, 11.2% self-identified as unusually sensitive to everyday chemicals such as cleaning products, perfume, and detergents, and 2.5% said they had been medically diagnosed with multiple chemical sensitivity (MCS).
Moderate evidence.
Caveats
Single national random-digit-dial telephone survey; self-report with no clinical verification of hypersensitivity or diagnosis; the earliest in a cross-country series of self-report chemical-sensitivity prevalence figures.
Source: Caress & Steinemann 2003, Archives of Environmental Health: An International Journal Link to this fact
Health effects / Self-reported survey
In a 10-country European cohort of 3,503 adults who did the cleaning at home and were asthma-free at baseline, using household cleaning sprays at least once a week was associated with a 49% higher rate of new asthma symptoms or asthma-medication use over about 9 years of follow-up.
Moderate evidence: Single multinational cohort (not yet independently replicated by a different research group); exposure and symptom outcomes were both self-reported at one follow-up interview.
Source: Zock et al. 2007, American Journal of Respiratory and Critical Care Medicine Link to this fact
Health effects / Self-reported survey
Using household cleaning sprays at least 4 days a week was linked to roughly double the rate of new physician-diagnosed asthma (HR 2.11, 95% CI 1.15-3.89) compared with light or no spray use, with a clear dose-response across frequency categories (P for trend 0.041) and number of different sprays used (P for trend 0.022).
Moderate evidence: Physician-diagnosed asthma relied on participant report of a doctor's diagnosis, not independent verification; single cohort.
Source: Zock et al. 2007, American Journal of Respiratory and Critical Care Medicine Link to this fact
Health effects / Self-reported survey
Cleaning products that were not applied as a spray (liquid multiuse cleaners, washing powders, polishes, bleach, ammonia, decalcifiers) showed no significant association with new-onset asthma in this study, while glass-cleaning, furniture, and air-refreshing sprays did.
Moderate evidence.
Caveats
Correlation between spray use and other product use was generally weak but not zero (Spearman's r up to 0.41 for some product pairs), so residual confounding by broader cleaning intensity cannot be fully excluded.
Source: Zock et al. 2007, American Journal of Respiratory and Critical Care Medicine Link to this fact
Health effects / Self-reported survey
The single highest-risk activity for asthma and nasal symptoms was manual dilution of concentrated disinfectant products (adjusted OR 4.01, 95% CI 1.34-12.00 for asthma; 1.90, 95% CI 1.13-3.18 for nasal symptoms), higher than general disinfection or cleaning tasks alone.
Moderate evidence.
Caveats
Task-level self-report from a single cross-sectional study; the authors interpret this as likely reflecting dilution errors that create exposure peaks to concentrated, strongly irritant product, not a tested causal mechanism.
Source: Gonzalez 2014, Clinical & Experimental Allergy Link to this fact
Health effects / Self-reported survey
Weekly use of disinfectant/cleaning sprays at work was associated with worse asthma control in US nurses (OR 1.50, 95% CI 1.16-1.94 for poorly controlled; OR 1.38, 95% CI 1.00-1.92 for very poorly controlled), and the association held even among nurses who used sprays less than once a week.
Moderate evidence.
Caveats
Self-reported spray use; the paper attributes the effect to higher inhalation potential from spray application rather than to a specific chemical, since sprays covered multiple product types (surface, patient care, air-refreshing).
Source: Dumas 2017, European Respiratory Journal Link to this fact
Health effects / Review of other studies
Formaldehyde, released by household cleaning products both directly and via reaction with indoor ozone, is described as a human carcinogen as well as a respiratory irritant.
Moderate evidence.
Caveats
This is a background descriptive statement in an emissions-chamber study, not new primary carcinogenicity data; it does not itself cite IARC or NTP classifications by name. Corroborated separately in our evidence base by US EPA's own indoor-air VOC guidance, which states plainly that benzene is 'a known human carcinogen' (src-2026-epa-voc-impact-indoor-air-quality) — so both halves of the video's statement (benzene and formaldehyde) are independently backed by evidence base source pages, though not yet as a combined graded claim.
Source: Rossignol 2013, Atmospheric Environment Link to this fact
Health effects / Other evidence
Four cleaning occupations (unspecified cleaners, domestic helpers and cleaners, helpers/cleaners in offices and hotels, and hand-launderers) were associated with adult onset asthma in this cohort, with odds ratios from 1.58 to 2.26; the offices/hotels cleaning code (OR 1.82, 95% CI 1.34-2.48) and home-based personal care workers (OR 1.94, 95% CI 1.40-2.69) remained significant after correcting for testing 61 occupations.
Moderate evidence: Job-title-level exposure, not product-level; the lowest estimate (unspecified cleaners, OR 1.58) did not reach significance on its own (p=0.078).
Health effects / Other evidence
Using a job-exposure matrix built specifically for asthma research (ASJEM), lifetime exposure to low-molecular-weight reactive cleaning or disinfecting products was associated with 67% higher odds of adult onset asthma (OR 1.67, 95% CI 1.26-2.22), the single exposure category that remained significant after correcting for 18 tested high-risk exposures (q<0.001).
Moderate evidence.
Caveats
The ASJEM exposure category is an expert judgment covering an unspecified mix of cleaning/disinfecting chemicals, not a named ingredient; single-cohort, not yet independently replicated.
Health effects / Self-reported survey
Among the same 113 migraineurs, 90.2% had migraine crises triggered by odors, and of those, perfume was by far the most common odor trigger (95.1%), followed by cleaning products (81.3%), cigarette smoke (71.5%) and motor vehicle exhaust (70.5%).
Moderate evidence: Self-report, unvalidated questionnaire, single clinical sample, no provocation testing of the named odors.
Source: Fornazieri 2016, Headache: The Journal of Head and Face Pain Link to this fact
Health effects / Measured in people or real products
Among hotel workers directly handling cleaning products, bleach, and laundry chemicals, the average estimated excess lifetime cancer risk from inhaled VOCs (4.1 in 100,000) was about 40 times the EPA's 1-in-a-million screening threshold, driven more than two-thirds by formaldehyde (then chloroform and benzene), even though measured VOC concentrations were at the low end of those reported in US buildings generally.
Moderate evidence: Preliminary/screening-level risk estimate extrapolated from short-term (6-9h) measurements to a 40-hr workweek; small sample (2 hotels); not a measured cancer incidence.
Health effects / Measured in people or real products
Despite directly and repeatedly handling cleaning products and bleach all shift, hotel housekeepers', laundry, maintenance, and office workers' calculated non-cancer hazard ratios for VOC exposure all fell below the standard threshold of 1 (ranging 0.3-0.5 across worker groups), though all remained above the more conservative 0.1 margin-of-safety benchmark the authors mention; formaldehyde contributed most of the hazard for every group except the single maintenance worker, where a lubricant-derived alkane (n-nonane) contributed slightly more (54% vs 46%).
Moderate evidence: Preliminary screening-level estimate from short-term sampling; maintenance-worker group size n=1.
Health effects / Other evidence
In a Belgian referral clinic, 17 of 44 workers (39%) who had asthma symptoms they linked to cleaning or disinfecting products had a measurable asthmatic reaction (a sustained 20% or greater fall in FEV1) when exposed to their own work products under controlled conditions.
Moderate evidence.
Caveats
Retrospective single-center chart review of workers referred (mostly via compensation claims); not a prevalence among cleaners. No blinding described; products were commercial mixtures and exposure was not measured.
Health effects / Other evidence
Of the 17 workers who reacted to cleaning products, 10 reacted to products containing quaternary ammonium compounds (mainly benzalkonium and didecyldimethylammonium chlorides), 3 to glutaraldehyde, 1 to both, and 2 to ethanolamines.
Moderate evidence.
Caveats
The causal agent was inferred from product ingredients, not isolated; 9 workers challenged with QAC-containing products did not react (derived from Table 1). Authors name lack of quantitative exposure assessment as the main limitation.
Health effects / Review of other studies
A 2016 review of professional clothing-cleaning methods reports that perchloroethylene (perc), the most widely used dry-cleaning solvent, is classed by the International Agency for Research on Cancer as probably carcinogenic to humans (group 2A), with kidney cancer, liver cancer, and non-Hodgkin lymphoma among the cancers linked to it in workers or residents.
Moderate evidence.
Caveats
Secondary review funded by Australian Wool Innovation (wool industry body); 'systematic' is a self-label with no study counts or appraisal; relies on agency, trade and manufacturer sources. The review restates other studies' findings; it contains no new exposure or outcome data, and the IARC class is a hazard rating, not a risk estimate for wearing dry-cleaned clothes.
Source: Troynikov 2016, Journal of Environmental Management Industry-funded Link to this fact
Health effects / Other evidence
The panel says frequent use of bleach, ammonia and degreasing sprays has been consistently associated with asthma in cleaning workers, but the specific chemicals and mechanisms are unclear because cleaning products contain many ingredients, some irritants and some sensitizers.
Moderate evidence: Occupational cleaners, not consumers; consensus statement; cited studies used qualitative exposure assessment.
Health effects / Review of other studies
Published cases of lasting asthma after a single accidental inhalation (RADS) have most often involved chlorine or chlorine-releasing chemicals, including cleaning of bathrooms, kitchens and toilets (44 cases in one series) and accidentally mixed chemicals at work.
Moderate evidence: Review of case reports, series and conference abstracts; mostly workplace accidents; frequency of report is not potency or incidence; no exposure levels.
Source: Walters 2020, Occupational Medicine Link to this fact
Health effects / Other evidence
In a random survey of 1,582 adults in the Atlanta, Georgia metro area (1999-2000), 12.6% said they were allergic or unusually sensitive to everyday chemicals like cleaning products, paints, perfumes, detergents and insect spray, and 3.1% said a doctor had diagnosed multiple chemical sensitivity or environmental illness.
Moderate evidence: Self-report only, one metro area; sampling frame, interview mode and response rate are not reported in this brief; no clinical verification.
Source: Caress & Steinemann 2004 (AJPH), American Journal of Public Health 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
In 2018, testing commissioned by Breast Cancer Prevention Partners of 25 personal care and 7 cleaning products found chemicals flagged for cancer, hormone disruption, respiratory, or developmental hazards that were not on the label; 99 of the 124 were on the fragrance industry's own ingredient list.
Moderate evidence: Not peer reviewed; labs, detection limits, and concentrations not reported; hazard = database flag; IFRA list includes multifunctional solvents/preservatives.
Source: BCPP 2018 Link to this fact
Hidden ingredients / Measured in people or real products
Di(2-ethylhexyl) phthalate (DEHP), a plasticizer used to make nail polish more flexible and durable, was the most abundant of six phthalates measured on silicone wristbands in all 10 nail salons tested (median 391.80 ng/g-wristband), with diethyl phthalate (DEP) second highest (median 154.4 ng/g-wristband) — but the paper never discusses what produces its measured DEP, unlike its explicit attribution of DEHP to nail polish and d-limonene to cleaning/fragrance products.
Moderate evidence.
Caveats
Small sample (n=10 for phthalates); wristband measurement is a sorbed dose, not a direct air concentration; the paper's own figures and Discussion text mislabel this unit as ppb instead of the Methods/footnote's ng/g-wristband, an internal inconsistency in the published article.
Source: Han et al. 2022 Link to this fact
Hidden ingredients / Other evidence
The workers were challenged with commercial cleaning products that contained mixtures of irritants and possible sensitizers, so the authors could not formally identify which ingredient caused each reaction.
Moderate evidence: Authors' own limitation statement; they infer QACs from known asthma-hazard predictions (asthma hazard index 0.81-0.95), which is a model score, not a test of the product.
Hidden ingredients / Measured in people or real products
The chamber test detected 530 distinct VOCs from 30 cleaning products and air fresheners, and only 17% of them appear in the cleaning industry association's ingredient database (American Cleaning Institute); 23 of 30 products were not fragrance-free and 7 of those listed just 'fragrance'.
Moderate evidence.
Caveats
EWG-authored (advocacy nonprofit that ranks cleaners and licenses EWG VERIFIED to cleaner makers); Skyline Foundation grant; unblinded; Detection of a chemical in chamber air does not show it was an intentional ingredient; some are impurities, by-products or sampling artifacts; 71% of VOCs were found in a single product.
Hidden ingredients / Other evidence
EWG Verified cleaning products must disclose every intentionally added fragrance ingredient publicly down to 0.01 percent, which no US federal rule requires of household cleaners.
Moderate evidence.
Caveats
Applies only to products that opt in and are licensed; the document states requirements, not compliance rates; amounts of ingredients are not disclosed. The comparison with US law relies on our other pages, not on this document.
Source: EWG Verified criteria for cleaning products (10.24), Environmental Working Group, 2024 Link to this fact
Information, not medical advice. See also: myths we won’t tell you.