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.
The industry / Animal study
This lavender study was funded by a university with no declared industry involvement, unlike much of the evidence used to argue these oils are safe for children, which comes from the essential-oil trade or from a manufacturer of lavender's main constituents.
Moderate evidence.
Caveats
Funding source is not evidence quality: this study is small (n = 5 per group) and the industry studies it contrasts with are larger and guideline-compliant, though narrower in scope.
Source: Kim & Lim 2022, Journal of Korean Medical Science Link to this fact
The industry / Animal study
The industry's guideline testing cleared the two lavender molecules that were NOT the most active ones: in the study it was answering, alpha-terpineol and terpinen-4-ol were the strongest on both the estrogen and androgen receptors, and BASF tested neither.
Moderate evidence: Comparison across two papers (Hareng 2024 vs Ramsey 2019) using different assay systems; the point is the untested molecules, not a disagreement about the tested ones.
Source: Hareng 2024, Archives of Toxicology Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
The hormone safety testing on lavender and tea tree oil constituents is incomplete: no regulatory steroidogenesis assay (OECD Test Guideline 456) has been published for any of the eight internationally defined constituents of either oil — including the two that an industry laboratory reported as clear on hormone receptors.
Moderate evidence: An absence-of-evidence claim about the published record as of 2026-09; states a testing gap, not a harm. Say 'not tested', never 'found unsafe'.
The industry / Review of other studies
Fragrance safety is self-regulated: IFRA, which represents about 90% of fragrance suppliers, issues voluntary guidelines, and much of the safety research it relies on is done by the industry's own institute (RIFM) and is unpublished.
Moderate evidence: Secondary figures; the unpublished-studies point is better sourced from RIFM dossiers themselves.
Source: BCPP 2018 Link to this fact
The industry / Industry source
The industry's standard safety package for a fragrance ingredient in 1994 covered acute poisoning and skin effects (irritation, allergy, sun reactions); breathing it in was not tested, because the industry judged inhalation 'not a route of toxicological concern'.
Moderate evidence.
Caveats
As of 2024, RIFM/Creme Global's aggregate exposure model (Lee 2024) does now include a full inhalation-TTC branch across ~3,000 fragrance ingredients (99% below the inhalation TTC), so the industry itself has since closed this specific 1994 scope gap methodologically — though whether ingredients assessed only under the older dermal-only dossiers were individually revisited is not stated. The gap's closure was gradual, not a single 2024 event: Comiskey et al. 2017 (Phase 2 of the same RIFM/Creme model) added the model's first-ever inhalation branch, 23 years after this 1994 dismissal, but only for air-care and personal-care spray products — household cleaning and laundry products were explicitly still excluded and named as future work in 2017, closing only in the 2024 paper.
Source: Ford 1994 (RIFM) Industry-funded Link to this fact
The industry / Review of other studies
EPA's reviewers warned that replacing one phthalate with a close relative (DINP for DEHP, DIBP for DBP) should not be assumed to be safer.
Moderate evidence: Based on weaker data for the substitutes (fewer studies, lower exposures), not on evidence they are equally harmful.
Source: Radke 2018 (US EPA), Environment International Link to this fact
The industry / Measured in people or real products
The essential-oil industry's published defense of lavender oil in a child's breast-growth case rested on showing the child's cologne was synthetic fragrance containing a phthalate: that clears lavender oil, not the cologne.
Moderate evidence: Describes the letter's argument; one case, no dose, no biomarker; does not show the phthalate or anything else caused the breast growth.
Source: Giroux & Orjubin 2020 (JCEM letter; Consortium Huiles Essentielles), The Journal of Clinical Endocrinology & Metabolism Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
A 2026 lab test that adds simulated human liver metabolism to a DNA-damage (Ames mutagenicity) test found MORE mutagenic activity in skin creams and lotions than the conventional animal (rat) version of the same test — the opposite of metabolism detoxifying the product. Standard safety testing, including industry fragrance-material dossiers, defaults to the rat version.
Moderate evidence.
Caveats
One paper, 11 unnamed cosmetic/skin-care-cream extracts, no compound identified; not tested on perfumes or on named fragrance materials; species differences in metabolism can go either direction depending on the chemical.
Source: Schmidtmann 2026, Analytical Chemistry Link to this fact
The industry / Review of other studies
The cosmetics industry's own safety panel found that 5% benzyl alcohol and 2% benzoic acid provoke a non-allergic skin reaction (redness, swelling, itching) in most people tested with no prior sensitization needed, yet concluded both are "safe" up to 5% in cosmetics because it judged typical exposure limited, not because the reaction is rare.
Moderate evidence.
Caveats
The exposure-limited reasoning was built around occasional hair-dye use; the same industry data table lists benzyl alcohol and benzoic acid in daily leave-on products (moisturizers, body/hand skin care) without a separate exposure justification for that pattern.
Source: Nair 2001 (CIR Expert Panel), International Journal of Toxicology Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
The replacement tests are least accurate for the strongest allergens: they were wrong by about 6-fold for strong sensitizers and about 18-fold for the most extreme ones, almost always guessing them weaker than they are.
Moderate evidence: Geometric-mean fold error by LLNA potency class (Table 4); no human-outcome validation for this specific breakdown.
Source: Natsch 2015, Toxicological Sciences Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
When the same lab-dish tests that replace animal testing are checked against real human allergy-test panels instead of mouse data, they explain only about 32-45% of how strongly a chemical causes allergy in people, and the mouse test itself does barely better, explaining only 43%.
Moderate evidence: The strictly-human comparison dataset (n=62) is small and the author flags it as biased/non-representative; a larger human dataset might do better.
Source: Natsch 2023, ALTEX Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
Neither the animal test nor its lab-dish replacements are strong predictors of real human allergy thresholds; they are about equally weak, shown independently in 2015 and again in 2023.
Moderate evidence: Both comparisons reuse overlapping historical human patch-test literature (HRIPT/HMT), not independent new human data.
Source: Natsch 2023, ALTEX Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
Whether a chemical is irritating to cells in a dish, not just whether it reacts with proteins, drives a lot of the mouse allergy test's readout in ways that don't reflect real human allergy.
Moderate evidence: Statistical inference from regression coefficients across three chemical subsets, not a direct mechanistic experiment.
Source: Natsch 2023, ALTEX Industry-funded Link to this fact
The industry / Review of other studies
AETT was in fragrance use for 22 years before its neurotoxicity was documented, and cosmetic color additives are the only ingredient class the FDA actually regulates.
Moderate evidence: Regulatory-gap claim is accurate for the 1979 US framework described in the paper; verify current FDA cosmetic regulation status before using as a present-tense claim.
Source: Spencer 1979, Science Industry-funded Link to this fact
The industry / Animal study
The study's own authors, including two Research Institute for Fragrance Materials scientists, stated that the doses causing clear nerve damage in rats were 50 to 250 times their own estimate of maximum human fragrance exposure to musk ambrette, and that the lower-dose, longer-term study needed to assess real human risk was never done.
Moderate evidence: This is the study authors' own stated limitation, not an independent follow-up; no lifetime low-dose study has been conducted since (as far as this evidence base has found).
Source: Spencer 1984, Toxicology and Applied Pharmacology Industry-funded Link to this fact
The industry / Animal study
Musk ambrette is no longer used in fragrances; it was withdrawn from all skin-contact products in the 1980s, following both this neurotoxicity finding and separate reports of photoallergic skin reactions in real-world cologne use.
Moderate evidence.
Caveats
The proximate cause of the total skin-contact ban was photoallergy (Cronin 1984), not the neurotoxicity finding directly, which RIFM had already argued had an adequate safety margin via absorption data.
Source: Spencer 1984; Ford 1994, Toxicology and Applied Pharmacology Industry-funded Link to this fact
The industry / Review of other studies
The fragrance industry's own most detailed exposure model to date estimates that about three-quarters of roughly 3,000 fragrance ingredients fall below a conservative safety threshold (TTC) for long-term systemic exposure, and 99% fall below it for inhalation — but by the same industry analysis, about a quarter of ingredients (777) are above their own systemic threshold and about half are above the skin-sensitization threshold (DST).
Moderate evidence.
Caveats
Industry-funded, self-run model (RIFM/Creme Global) using industry-supplied, largely unpublished concentration and habits-and-practices survey data. The DST gap is driven mostly by natural complex substances (essential oils etc.), which are conservatively defaulted to the more hazardous 'reactive' category without analyzing their actual components — only 19% of these clear the DST versus 65% of single, chemically-defined ingredients.
Source: Lee 2024 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Review of other studies
As of 2024, the fragrance industry's aggregate exposure model finally covers household-care, air-care, and oral-care products and the inhalation route for its full ~3,000-ingredient inventory — a scope earlier industry safety dossiers from 1994, 2003, and 2007 explicitly left out or dismissed by a single-ingredient calculation.
Moderate evidence.
Caveats
Whole-inventory average from an industry-run model; the paper does not show that any specific earlier dossier (e.g. the 2007 salicylates group review) was individually re-run through the expanded model, so whether that scope gap has closed for those specific materials is unconfirmed.
Source: Lee 2024 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Review of other studies
The industry's own model finds fragrance exposure from household-care and air-care products is far lower than from cosmetics and personal-care products, and almost entirely by inhalation rather than skin contact (household 95th percentile 0.2 ug/kg/day, air care 5 ug/kg/day, versus cosmetics/personal care about 50 ug/kg/day, nearly all dermal).
Moderate evidence: Based on a 350-ingredient sample modeled from industry-supplied concentration and use-frequency survey data, not measured breathing-zone concentrations.
Source: Lee 2024 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Government agency
FDA's own 2006 testing concluded there was insufficient data to find a human health hazard from phthalate esters in cosmetics and took no regulatory action, even though the phthalates were already known to be common and concentrated in fragrance and nail products.
Moderate evidence: This is the regulator's own stated position at the time (2006), not a new toxicity finding; FDA said it would continue to monitor and could revisit if new hazard data emerged.
Source: Hubinger & Havery 2006, Journal of Cosmetic Science Link to this fact
The industry / Industry source
The fragrance industry's aggregate consumer exposure model did not include any estimate of inhaled fragrance exposure until 2017, when it added an inhalation route for air fresheners, scented candles, and personal-care sprays only — 23 years after the industry's 1994 safety package dismissed inhalation testing.
Moderate evidence.
Caveats
This is a modeled inhalation exposure fraction from a compartmental model run at single default parameter values, not measured breathing-zone data; the model's own validation against real chemical concentrations is reported in a companion paper (Safford et al. 2017) not yet in this evidence base.
Source: Comiskey 2017 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded 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
The industry / Industry source
To build this exposure model, the fragrance industry combined three surveys that were never designed to work together — a 7-day product diary, a monthly recall survey, and a categorical daily-frequency questionnaire — by matching subjects only on age and gender and assuming they share the same habits for entirely unrelated products.
Moderate evidence.
Caveats
The paper's authors are explicit about this assumption's uncertainty and do not test it directly; a companion validation paper (Safford et al. 2017) is not yet in this evidence base to check how much this integration step affects final exposure estimates.
Source: Comiskey 2017 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Industry source
Some of the amount-per-use values feeding this industry exposure model come from very small studies — 10 Dutch adults for bar-soap-in-the-shower amounts, and a single non-distributional value for scented-candle amount per day — rather than large, representative samples.
Moderate evidence.
Caveats
Small external studies feeding a large aggregate model is a data-provenance observation, not itself evidence the resulting exposure estimates are biased in a particular direction; the paper does not report sensitivity analysis on these specific inputs.
Source: Comiskey 2017 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
The fragrance industry's own 2007 safety review of benzyl salicylate assessed allergy, toxicity, and cancer risk in detail but never tested it for hormone-like activity at all; the first test came two years later, from an independent lab with no fragrance-industry funding.
Moderate evidence.
Caveats
The independent test found only a weak, partial effect, at concentrations well above the industry's own worst-case exposure estimate, so this closes a testing gap rather than reversing the 2007 review's 'safe as used' conclusion.
Source: Charles & Darbre 2009, Journal of Applied Toxicology Link to this fact
The industry / Measured in people or real products
In RIFM's own comparison of 57 fragrance chemicals, the mouse test used to set fragrance skin-allergy safety limits agreed with real human sensitization thresholds within about 3-fold for 76% of the chemicals tested, but was off by up to nearly 800-fold for others, including hexyl and benzyl salicylate.
Moderate evidence.
Caveats
Single paper/author group (RIFM staff plus an industry consultant), though a large (57-chemical), systematically protocolled primary dataset; the authors themselves call the outlier groups 'an alert for consideration, rather than… a general rule' given only 7 materials populate each. Corroborates, from a different metric and era, the LLNA-human accuracy gap C230 documents for the newer non-animal replacement tests.
Source: Api, Basketter & Lalko 2014, Cutaneous and Ocular Toxicology Industry-funded Link to this fact
The industry / Measured in people or real products
The older claim that PGME solvent vapor irritates the eyes and throat at 250 ppm comes from an unblinded 1970 study without objective eye measurements (20 of 23 subjects reported eye irritation at 250 ppm); a later double-blind study with objective eye tests found no effect at 100-150 ppm.
Moderate evidence.
Caveats
The double-blind study only tested up to 150 ppm, so it does not directly re-test the 250 ppm figure; it undermines confidence in the method that produced it, not the number itself.
Source: Emmen et al. 2003, Toxicology Letters Industry-funded Link to this fact
The industry / Government agency
California's 2022 law banning intentionally added PFAS in cosmetics (AB 2771), effective January 1, 2025, is expected by state toxicologists' own modeling to reduce PFAS reaching California wastewater treatment plants, particularly from shaving creams and gels, hair care products, and facial cleansers rather than from makeup.
Moderate evidence.
Caveats
This is a projection from the same modeled estimate, not a before/after measurement; the ban had not yet taken effect when the paper was published, and DTSC has an institutional interest in the policy it also administers.
Source: Balan 2024, Environmental Science & Technology Link to this fact
The industry / Measured in people or real products
The study's own authors note that current diagnostic patch-test concentrations for oxidized linalool allergy are more than 500 times higher than the hydroperoxide levels they actually found in consumer products.
Moderate evidence: Industry-funded interpretation; does not itself prove patch tests over-diagnose, since already-sensitized skin can react to much lower doses than the diagnostic test threshold.
Source: Kern 2014, Analytical and Bioanalytical Chemistry Industry-funded Link to this fact
The industry / Other evidence
RIFM's founding scientific director personally authored the sole primary study behind the fragrance industry's 'quenching' safety exception; IFRA later codified it into a formal use-with-limonene rule (≥25% d-limonene) that required a higher proportion of the 'quenching' terpene than Opdyke's own 1976 test (~20% d-limonene) actually used.
Moderate evidence: The evidence base does not have IFRA's own documentation of why 25% (rather than the tested ~20%) was chosen, or of when/why the quenching exception was later withdrawn.
Source: Ford 1994 (RIFM), citing Opdyke 1976 Industry-funded Link to this fact
The industry / Measured in people or real products
Despite thousands of positive allergy-test reactions to oxidized limonene and linalool reported worldwide, the fragrance industry's own market-testing program concluded that where people are actually getting exposed to these allergens "remains elusive" — the industry itself has not identified the real-world consumer-product source of a widely documented skin allergy.
Moderate evidence.
Caveats
This is the industry's own conclusion, from an industry-funded study; it does not mean the allergy is not real or not caused by fragrance chemicals — only that the specific consumer-product exposure route has not been chemically confirmed even by the party with the strongest incentive to find an innocuous explanation.
Source: Natsch 2019, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Measured in people or real products
A musk fragrance chemical called ATTN (Versalide) disappeared entirely from human tissue in this 1996 study because industry had already stopped making it in 1980, after animal testing showed it damaged nerves – a real-world example of a musk being phased out after a toxicity finding.
Moderate evidence: Absence in 19 samples is consistent with, but does not by itself prove, the discontinued-production explanation the authors give; based on a small single-country sample.
The industry / Measured in people or real products
SC Johnson funded and co-authored a study that tested what was apparently its own newly developed fragranced air-sanitizer product in asthmatics and found no adverse ocular, nasal, or lung effects.
Moderate evidence.
Caveats
Record as the industry's own finding, not independent confirmation of safety; the null is broadly consistent with independent Elberling 2006/Millqvist findings but was not independently replicated.
Source: Opiekun 2003, Clinical and Experimental Allergy Industry-funded Link to this fact
The industry / Animal study
When RIFM's own scientists restrict the comparison to fragrance chemicals without known problematic chemistry, the mouse test used to set fragrance safety limits correlates strongly with real human sensitization thresholds (R-squared = 0.78 for 35 chemicals).
Moderate evidence.
Caveats
This correlation excludes, by design, the 14/57 chemicals already known (from the same underlying RIFM dataset) to disagree badly between mouse and human data, some by up to ~790-fold (Api 2014). Only 2 of those 14 exclusions could have been identified before seeing the human data; the other 12 were fit to the very outliers they exclude.
Source: Roberts & Api 2018, Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Measured in people or real products
This foundational human PGME irritation study has a direct Dow Chemical link stronger than later PGME papers in the wiki: one author was a Dow Chemical employee and the test material was Dow-supplied ('Dowtherm 209'), yet the study documents substantial irritation at concentrations relevant to Dow's own radiator-coolant product rather than minimizing it.
Moderate evidence: A single industry-linked study reporting an adverse finding is still one study; the funding link is recorded for transparency, not as proof the finding is unbiased in general.
Source: Stewart 1970 (Arch Environ Health), Archives of Environmental Health: An International Journal Industry-funded Link to this fact
The industry / Animal study
A commercial testing laboratory's mouse-bioassay claims of consumer-product toxicity (the same ASTM E-981/FOB method the lab later applied to air fresheners and colognes) failed an independent, blinded EPA/ManTech replication attempt when applied to carpets; the largest toxicity-looking signals traced instead to stress from the restrained-exposure test procedure itself, present even in air-only control animals.
Moderate evidence.
Caveats
Applies to carpets specifically (2 CPSC-complaint carpets, one lab-replication attempt); the fragrance papers' headline airflow-limitation (mid-expiratory flow) endpoint was never measured by this study, so it is method/lab-level caution about the testing program, not a direct refutation of the fragrance-specific findings.
Source: Tepper et al. 1995, American Industrial Hygiene Association Journal Link to this fact
The industry / Review of other studies
Modern (post-1980s) European fabric conditioners almost all use esterquats, a cationic surfactant class engineered with a hydrolyzable ester linkage to biodegrade faster than the older DHTDMAC/DSDMAC softeners it replaced; the industry's own account frames the switch as environmental (biodegradability), not human-health, driven.
Moderate evidence.
Caveats
Industry source, coi/industry-funded, unnamed underlying studies; the chemistry/history claim itself (ester linkage -> faster hydrolysis/biodegradation) is basic, uncontested chemistry, but the framing and any 'therefore always safer' inference is the industry's own.
Source: HERA Project 2008 (A.I.S.E./CEFIC) Industry-funded Link to this fact
The industry / Measured in people or real products
Tumble dryer manufacturers give directly conflicting instructions on cleaning the lint filter: some tell consumers to rinse it under water, others recommend a dishwasher, others dry methods only, and one (John Lewis) explicitly says never use water, for environmental reasons.
Moderate evidence: One UK market snapshot (24 brands, January 2023), not checked against other countries or against what consumers actually do.
Source: Cummins 2023, PLOS ONE Industry-funded Link to this fact
The industry / Other evidence
The clinical safety testing (HRIPT, CIT, or SIU) required to earn the NEA Seal is arranged and paid for by the manufacturer through a testing company of its own choosing; NEA states it "does not endorse or have a relationship with any clinical safety testing company" and instead reviews the submitted reports on paper through an independent physician panel.
Moderate evidence.
Caveats
This is a structural/COI description from the criteria page itself, not a finding that any specific product's submitted testing was inadequate; whether NEA audits the chosen labs is unknown from this page (see linked-but-uncaptured testing-requirements PDF).
Source: NEA 2026 Link to this fact
The industry / Review of other studies
The US fragrance and cosmetics industry's principal safety-review and standard-setting bodies (IFRA, RIFM/REXPAN, the Personal Care Products Council, the Cosmetic Ingredient Review, the Voluntary Cosmetics Regulation Program) are industry-created and industry-funded, and their safety findings are not legally binding on member companies.
Moderate evidence.
Caveats
Institutional description only, as of 2010-11; does not measure whether member companies actually comply. IFRA's Standards list was described as subscription-only at the time; a separate, later 'IFRA Transparency List' is cited elsewhere in our evidence base as publicly accessible, so 'IFRA's list is not available to the public' should not be repeated without specifying which list.
Source: Reebs 2011 Link to this fact
The industry / Measured in people or real products
This 1977 dose-response safety study of a laundry-product preservative was conducted and authored in part by Procter & Gamble, the product's manufacturer, using an experimental in-house formulation; the co-author (Maibach) who supplied the sensitization-testing methodology also co-authored the wiki's other major P&G-funded laundry allergic-contact-dermatitis study 25 years later (Belsito et al. 2002).
Moderate evidence.
Caveats
Recurring author/sponsor relationship across our two main laundry-product ACD safety studies is relevant context for weighing how independent they are of each other, not evidence that either study's data are wrong.
Source: Weaver & Maibach 1977, Contact Dermatitis Industry-funded Link to this fact
The industry / Other evidence
In a random sample of 100 high-production-volume industrial chemicals, 47 were also listed on EPA's Toxics Release Inventory (meaning they are emitted into air, land, or water in quantities over 10,000 pounds a year), and toxicity data were publicly available for less than half of those 47.
Moderate evidence: A single external audit, not independently replicated; concerns industrial chemicals broadly, not a named fragrance or consumer-product ingredient.
Source: Goldman 1998, Environmental Health Perspectives Link to this fact
The industry / Measured in people or real products
This study — the largest and most-cited test of whether laundry detergents cause allergic contact dermatitis — was funded by Procter & Gamble, which also supplied both detergents tested and had previously conducted its own unpublished non-irritancy testing of the same test concentrations with one of the study's authors.
Moderate evidence.
Caveats
The multicenter NACDG design, blinded phases II/III, and the authors' own caveats about probable false-positive irritant reactions argue against simple result-shopping, but no independently funded replication exists to check the direction of the funding effect.
Source: Belsito et al. 2002, Journal of the American Academy of Dermatology Industry-funded Link to this fact
The industry / Animal study
Unilever toxicologists reviewed 92 public rat inhalation toxicology studies (from US EPA HPV/OECD SIDS reports and BfR, TNO, and ECETOC evaluations) and derived generic inhalation 'thresholds of toxicological concern' (TTCs), so that a consumer aerosol ingredient's measured exposure could be compared to a threshold instead of running a new ingredient-specific inhalation toxicology study.
Moderate evidence.
Caveats
Single industry research group (Unilever); the TTC framework is a conservative screening tool, not a replacement for chemical-specific testing when structural alerts or existing hazard data raise concern, and it explicitly excludes polymers and several other chemical classes.
Source: Carthew, Clapp & Gutsell 2009, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Animal study
The paper's proposed inhalation systemic TTC ranges from 16.4 μg/kg/day for the least-toxic Cramer Class 1 chemicals down to 2.8 μg/kg/day for the more toxicity-presumptive Class 3 chemicals (roughly a 6-fold spread), while its separate local respiratory-tract TTC ranges from 2.1 to 0.73 μg/g lung tissue/day (about a 3-fold spread) — equivalent to 980/170 μg/day and 1400/470 μg/day respectively for a 60 kg adult.
Moderate evidence.
Caveats
Derived from the 5th percentile of NOAEC/NOAEL across 92 rat studies plus a 25-fold uncertainty factor; a conservative statistical screening threshold, not a measured no-harm level, and the paper treats local and systemic thresholds as two separate comparisons that later citations sometimes conflate.
Source: Carthew, Clapp & Gutsell 2009, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Animal study
The dataset behind these inhalation TTCs excluded genotoxic carcinogens, in vivo mutagens, heavy metals, dioxins/PCBs, organophosphates, and polymers — chemical classes the authors say would already be disqualified from consumer aerosol use on other safety grounds — before applying a default uncertainty (safety) factor of 25 to the 5th-percentile NOAEC/NOAEL of the remaining 92 rat studies.
Moderate evidence.
Caveats
Exclusion criteria and the 25-fold uncertainty factor are the authors' own choices, following precedent from the oral/dietary TTC literature; not independently audited by a regulator.
Source: Carthew, Clapp & Gutsell 2009, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Animal study
Only 5 of the 92 chemicals in the database had local (respiratory-tract) NOAECs below the study's own 5th-percentile benchmark — sulfuric acid, trimellitic acid, glutaraldehyde, hydrogen peroxide, and 1,2-dichloro-4-nitrobenzene — and all were strong acids, bases, or reactive irritants that the authors say would already be excluded from consumer aerosol use on physicochemical grounds alone.
Moderate evidence.
Caveats
A post-hoc observation about which chemicals happened to fall below the benchmark in this specific 92-study set; not a claim that physicochemical screening alone catches every locally toxic inhalable chemical.
Source: Carthew, Clapp & Gutsell 2009, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Animal study
The paper reports its inhalation-derived systemic TTCs (980 μg/day Class 1, 170 μg/day Class 3, for a 60 kg adult) sit within, and are not dramatically lower than, the oral-exposure-derived systemic TTCs for the same Cramer classes (1800 and 90 μg/day) — despite the inhalation calculation assuming 100% absorption versus the oral route's assumed 50% absorption factor.
Moderate evidence.
Caveats
A comparison the authors themselves frame as reassuring; it does not establish that the inhalation route is equally well characterized as the oral route, only that the two threshold estimates are of similar magnitude for these particular chemical classes.
Source: Carthew, Clapp & Gutsell 2009, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Review of other studies
All three named authors of this inhalation-TTC methodology paper were Unilever employees at Unilever's own research center (Colworth Science Park, UK), and the paper states 'The authors declare that there are no conflicts of interest' even though the work was industry research explicitly aimed at reducing inhalation-toxicology testing requirements on the authors' own company's aerosol consumer products under REACH and the EU Cosmetics Directive's 2013 animal-testing ban.
Moderate evidence.
Caveats
A self-declared 'no conflicts of interest' statement from an industry-employed author group performing industry-funded research aimed at reducing regulatory testing burden on their own company's products.
Source: Carthew, Clapp & Gutsell 2009, Food and Chemical Toxicology Industry-funded Link to this fact
The industry / Journalism
The fragrance industry trade group RIFM (Research Institute for Fragrance Materials) publicly disputed the dryer-vent study, arguing it did not rule out the dryers, ambient air, or towels as VOC sources and lacked enough methodological detail for independent replication.
Moderate evidence.
Caveats
Coi/industry-funded framing: RIFM is a fragrance-industry trade association responding to a study on its own members' products; quoted on-the-record via a press release and interview, not itself a data-based rebuttal.
Source: Kessler 2011 (EHP Forum), Environmental Health Perspectives Link to this fact
The industry / Industry source
The fragrance industry's aggregate consumer exposure model began in 2015 covering 19 personal-care and cosmetic product types across a 36,446-subject Europe/US survey, using dermal and oral exposure routes only — it did not estimate inhaled fragrance exposure at all.
Moderate evidence.
Caveats
This is the founding Phase 1 methods paper of the same RIFM/Creme model line whose Phase 2 (Comiskey 2017) added a first, partial inhalation route two years later, and whose Phase III (Lee 2024) closed the gap industry-wide nine years later.
Source: Comiskey 2015 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Industry source
This industry exposure model's default assumptions are stated by its own authors to be conservative: 100% of a fragranced product applied to skin is assumed absorbed, and 100% of the contents of a spray product (body spray, eau de parfum, eau de toilette) is assumed to land on the skin, with none modeled as inhaled or lost to the air.
Moderate evidence.
Caveats
The authors state these assumptions generally push exposure estimates upward (toward overestimation), which is standard conservative risk-assessment practice, but this is a stated design choice, not something independently verified against measured human exposure.
Source: Comiskey 2015 (RIFM/Creme Global), Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Other evidence
The fragrance industry's own probabilistic (Monte Carlo) exposure model estimated aggregate systemic exposure for four fragrance ingredients (vanillin, benzaldehyde, BMHCA, isoeugenol) at 11.5 to 25-fold lower than the deterministic worst-case method recommended by the EU's SCCS for assessing cosmetic ingredient safety.
Moderate evidence.
Caveats
Industry-funded (RIFM); both sides of the comparison are modeled, not measured; limited to 4 of the 8 ingredients studied and to 13 of the SCCS's 17 product types (the model does not cover 4 make-up categories).
Source: Safford 2017, Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Other evidence
In this industry model, the highest simulated exposure to vanillin came from body lotion (prestige range, P95 8.79 mg/kg bw/day), eau de parfum (8.34) and eau de toilette (6.34), while plug-in air freshener and scented candles — despite having the highest simulated in-product concentrations of vanillin — produced comparatively low exposure (P95 1.81 and 0.81 mg/kg bw/day) because there is no direct skin contact and the modeled inhalation fraction is low.
Moderate evidence: Modeled, not measured; industry-funded (RIFM); pattern shown for vanillin, generalized by the authors to the other 7 ingredients tested.
Source: Safford 2017, Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Other evidence
The same industry exposure model's aggregate (whole-population) P95 exposure estimate can be lower than its own P95 exposure estimate among consumers of a single high-exposure product, because usage of any one product type is well under 100% of the population — e.g. body lotion use was modeled at about 17.3% of the population, and body spray, mouthwash, and hand cream use at only 1-2%.
Moderate evidence: Modeled usage proportions from industry-commissioned survey data (Kantar, SUPERB, BodyCare), not independently verified.
Source: Safford 2017, Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
The industry / Lab study (cells or chemistry)
The study comparing BAK against a preservative-free alternative (TBE) was co-authored by an employee of Lion Corporation, the company behind the TBE formulation, and declared no conflict of interest despite this employment relationship; no external funding was received.
Moderate evidence.
Caveats
This is an employer/product-interest conflict, not a disclosed funding conflict; the paper's own stated 'no conflict of interest' should not be taken at face value given the named employment tie to the favorably-assessed product.
Source: Kabashima 2020, Journal of Ocular Pharmacology and Therapeutics Industry-funded Link to this fact
The industry / Measured in people or real products
The same manufacturer developed and scaled up (to an 11-kilogram batch) a process that keeps PFOA below the 5 ppb detection limit: irradiating PTFE with gamma rays inside a sealed, oxygen-free polymer bag, then heat-treating it at about 150 degrees C, with the low PFOA level still holding after a year of storage.
Moderate evidence.
Caveats
Industry-authored process-development study (Daikin Industries); demonstrates the company's own manufacturing improvement rather than an independent audit, and describes production of industrial low-Mw PTFE micropowder for wax/automotive/printing uses, not a named cosmetic product.
Source: Oshima et al. 2020, Scientific Reports Industry-funded Link to this fact
The industry / Measured in people or real products
The study authors point out that a batch of PTFE can be made to test 'PFOA-free' simply by heat-treating it in open air, but they state this only evaporates the PFOA into the surrounding atmosphere rather than destroying it, and call this approach a clear violation of the EU REACH regulation rather than a genuine fix.
Moderate evidence.
Caveats
This is the authors' own regulatory interpretation of their lab results, not an independent legal analysis; concerns industrial off-gassing during manufacture, not a described exposure route for a finished cosmetic or consumer product.
Source: Oshima et al. 2020, Scientific Reports Industry-funded Link to this fact
The industry / Review of other studies
When RIFM's own scientists switched from mainly human patch-test data (their 2017 categorization) to a full weight-of-evidence approach that also folds in animal, computer-model, and lab-dish data, the assigned allergy-potency category changed for 29% of the same 82 fragrance chemicals — moving to a weaker category for 20.5% of them and a stronger one for 8.5%.
Moderate evidence.
Caveats
Same authors and institution comparing their own two categorization schemes; independent validation of either scheme against real-world human sensitization rates is not addressed in this paper.
Source: Na et al. 2022, Dermatitis Industry-funded Link to this fact
The industry / Measured in people or real products
Perfume that washes off fabric during rinsing does not just disappear into the drain: as surfactant concentration drops below the critical micelle concentration (measured at about 73.4 ppm in this study), micelles trapped in the wet fabric break open and redeposit their more hydrophobic perfume ingredients back onto the fabric, more strongly on cotton than on polyester because cotton retains far more water after spinning (about 0.7 kg water per kg dry cotton vs about 0.1 kg/kg for polyester).
Moderate evidence.
Caveats
Coi/industry-funded (Procter & Gamble); single small-scale bench wash simulator, one model detergent formulation, and one synthetic perfume accord; mechanism inferred from surfactant titration and headspace GC-MS, not directly visualized.
Source: Marcotullio 2025, Journal of Surfactants and Detergents Industry-funded Link to this fact
Information, not medical advice. See also: myths we won’t tell you.