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 / Self-reported survey
Every one of 13 Washington DC childcare facilities that reported health data had at least one child with physician-diagnosed asthma, with a typical (median) facility rate of about 10%.
Weak evidence: Center-Director-reported, not chart-confirmed; no exposure-outcome link tested; n=13.
Source: Quirós-Alcalá 2016, Environmental Research Link to this fact
Children and pregnancy / Government agency
In animal studies, a pregnant female's exposure to an endocrine-disrupting chemical can affect not only her offspring but her offspring's offspring, because developmental exposure can alter reproductive-cell programming that carries across generations.
Weak evidence: Evidence for these transgenerational effects comes from animal studies cited in the report; no multigenerational human dataset is cited for this specific claim.
Source: WHO/UNEP 2012 Link to this fact
Children and pregnancy / Other evidence
A 2020 review states that endocrine-disrupting chemicals found in the placenta (pesticides, personal care product chemicals, flame retardants, BPA, PCBs) could be associated with fetal growth restriction, thyroid dysfunction, and neurological disorders, but the mechanisms are largely unknown.
Weak evidence: Association stated through a single cited review; mechanisms rest largely on animal and small human studies; not a demonstrated causal risk.
Source: Street 2020, International Journal of Molecular Sciences Link to this fact
Children and pregnancy / Measured in people or real products
In the same study, higher DEHP in carpet dust (a plastics phthalate, not a fragrance one) was more common in homes of the 27 children with developmental delay (odds ratio 2.12, 95% CI 1.10-4.09 per ln-unit), but the authors report the finding did not survive correction for multiple comparisons and may be due to chance.
Weak evidence: 27 cases; exposure measured after the delay was already present (reverse causation possible); DEHP is not a fragrance ingredient; abstract states OR 2.10, table 2.12.
Source: Philippat 2015 (CHARGE), Environmental Health Link to this fact
Children and pregnancy / Review of other studies
In a 2019 review, newborn total thyroxine from heel-prick screening cards did not predict a later ADHD diagnosis (ORs 0.99 and 1.08, CI 0.95-1.24), and newborn TSH did not predict ADHD symptoms at ages 4-5.
Weak evidence: Few studies; sample timing after birth was not adjusted; some studies may share participants.
Children and pregnancy / Measured in people or real products
In the same Baltimore children, recent scented candle use went with about 2.6 times higher urine methyl paraben (2.57, 95% CI 1.09-6.06) and scented carpet powder with about 2.8 times higher 2,5-dichlorophenol (2.77, 1.21-6.34), but only in models adjusting for other products; the candle result was not significant on its own (2.32, 0.95-5.64).
Weak evidence: Wide intervals, many comparisons, and the authors say carpet powder may only mark carpeted homes; no ingredients checked.
Source: Fandiño-Del-Rio 2024, Journal of Exposure Science & Environmental Epidemiology Link to this fact
Children and pregnancy / Other evidence
In the same Korean first-trimester cohort, triclosan, benzophenone-3 and methyl-, ethyl-, propyl- and butylparaben (personal-care-product chemicals) were not associated with TSH or with the oxidative-stress markers MDA and 8-OHdG.
Weak evidence: A null from one small cohort with one spot urine per woman; it does not show safety, and it contradicts earlier cohorts the authors cite (propylparaben, BPS).
Source: Kim 2025, Environmental Analysis Health and Toxicology Link to this fact
Children and pregnancy / Other evidence
Tobacco smoke exposes a fetus to a mixture including carbon monoxide, ammonia, nitrogen oxides and metals, so animal nicotine findings cannot be assigned to nicotine alone in people; tobacco smoke is not a fragrance ingredient.
Weak evidence: Animal findings (rats, mice, guinea pigs) are not human evidence; no fragrance exposure studied.
Source: Knopik 2009, Developmental Neuropsychology Link to this fact
Fragrance is everywhere / Self-reported survey
Among Atlanta-area adults who reported chemical hypersensitivity, symptom onset was reported before age 20 in about a third of cases (32.4%), suggesting hypersensitivity is not exclusively an adult-onset condition.
Weak evidence.
Caveats
Retrospective self-report of childhood/adolescent onset in adults; no pediatric clinical verification; age-of-onset table has an internal mismatch with the running text for the older age brackets (see the page's Notes).
Source: Caress & Steinemann 2003 (EHP), Environmental Health Perspectives Link to this fact
Fragrance is everywhere / Other evidence
Shopping malls can diffuse a scent blend through their common areas, installed by a professional scent-marketing agency, so every visitor is exposed without any way to opt out; the mall studied used orange, grapefruit, bergamot, cinnamon, cardamom, ginger, and pimento 'and other additives'.
Weak evidence: A single research mall; no concentration or full composition was reported, and the paper makes no health or allergen claim.
Source: Teller 2012, Journal of Marketing Management Link to this fact
Fragrance is everywhere / Other evidence
In the industry's illustrative model of 36,446 US and European adults, the 95th-percentile person received about 7.55 g/day of product on the skin and in the mouth from 19 personal-care product types, with mouthwash, mass-market body lotion, and deodorant roll-on the largest contributors.
Weak evidence: Model output from 2007-2008 diary data, industry-funded; Fig. 3 shares are read from a chart.
Source: Safford et al. 2015, Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
Fragrance is everywhere / Other evidence
After spraying a car air freshener, benzene and several other aromatic VOCs measured in the cabin went down by an average of about 40% for benzene (except in recirculation mode) while limonene went up, so the product masks rather than removes the car's own chemicals.
Weak evidence: The sprays contained no benzene; the drop was transient, came with no unsprayed control, and the authors' masking/displacement explanation was not tested.
Source: Lee 2024, Science of The Total Environment Link to this fact
Fragrance is everywhere / Other evidence
CTV reported a 2014 survey finding about 2.4 per cent of Canadians (more than 770,000) have been diagnosed by a health-care provider with MCS.
Weak evidence: CTV does not name the survey; primary source not checked here. Do not repeat as established until the primary is found.
Source: CTV News, April 2022 (via Smoke-Free Housing BC; redacted copy), CTV News (news article) Link to this fact
Green, natural and unscented / Measured in people or real products
Scented tampons carried a median of 692 ng/g of fragrance terpenes against 2.9 ng/g in unscented ones.
Weak evidence: Only 2 scented vs 20 unscented tampons (p=0.04).
Source: Lin 2020, Environment International Link to this fact
Green, natural and unscented / Other evidence
Candles made from renewable waxes (beeswax, soy, coconut, palm) scented with natural essential oils are generally safer and more sustainable than paraffin candles, but still carry an environmental cost through deforestation and habitat destruction from increased crop demand.
Weak evidence.
Caveats
No emissions or land-use quantification given; our own chamber data (Salthammer 2021, Andersen 2021) also show wax type has little effect on formaldehyde/PAH output compared to fragrance load, so a wax switch alone may not reduce indoor-air health risk even if it changes the environmental footprint.
Source: Singh 2023, Environmental Science & Technology Link to this fact
Health effects / Lab study (cells or chemistry)
In lab tests on cancer-derived nerve cell lines, three unnamed commercial fragrances changed cell shape and structure after 72 hours and cut the share of cells carrying oxytocin and vasopressin receptors in some lines but not others.
Weak evidence: Cell lines only; fragrances unidentified; no replication; only one cell line per sex.
Source: Sealey 2015, Environmental Research Link to this fact
Health effects / Hypothesis
Silent Spring Institute researchers name house cleaners and nurses as priority jobs for cutting exposure to fragrance, cleaning, and personal-care chemicals linked to breast cancer in lab and animal studies.
Weak evidence: No exposure or cancer data in these workers.
Source: Knox 2026, Journal of Exposure Science & Environmental Epidemiology Link to this fact
Health effects / Lab study (cells or chemistry)
Musk ketone does not damage DNA by itself, but in rat liver enzymes and human liver cells it made known carcinogens like benzo[a]pyrene more mutagenic.
Weak evidence: One laboratory's data (the review's senior author); human-cell LOEL 50 ng/ml is 12-70x above whole-milk levels.
Source: Schmeiser 2001, International Journal of Hygiene and Environmental Health Link to this fact
Health effects / Lab study (cells or chemistry)
In human adrenal cells, eight common fragrance terpenes, eucalyptol, geraniol, carvone, 3-carene, ocimene, both pinenes, and dihydro-beta-ionone, cut production of the androgen precursor DHEA by 13–31%, and six others cut the activity of aromatase, the enzyme that makes estrogen, by 22–33%.
Weak evidence.
Caveats
Single 10 µM concentration, ~140–200× above what indoor air or ordinary product use could produce internally; the mass-spectrometry check was non-significant for eucalyptol (p = 0.0574) and null for dihydro-beta-ionone; the same 10 µM killed up to 50% of a prostate-cancer cell line by 48 h. Always state the concentration.
Health effects / Review of other studies
Citronella oil, marketed as a natural insect repellent, has been banned in the European Union and Canada since 2006, partly because it contains methyl eugenol, which the US National Toxicology Program considers 'reasonably anticipated to be a human carcinogen' based on animal studies.
Weak evidence.
Caveats
No human carcinogenicity data exist for methyl eugenol; this is a regulatory ban and an animal-based NTP classification relayed by a secondary review, not measured harm from using citronella products.
Source: Ramsey 2020 (YJBM), Yale Journal of Biology and Medicine Link to this fact
Health effects / Review of other studies
Some solvents can theoretically sensitize the heart muscle to the body's own adrenaline-type hormones, raising a theoretical risk of arrhythmia or cardiac arrest under chemical exposure in people with multiple chemical sensitivity.
Weak evidence.
Caveats
Cited from a toxicology reference textbook (Olson, Acute Intoxications, Poisons, Pharmaceutical Substances and Drugs), not from any MCS-specific study; the review's own authors state this risk "has not been detected in any epidemiological study so far." Mechanistic/theoretical only.
Source: Rossi 2018, Journal of Occupational & Environmental Medicine Link to this fact
Health effects / Measured in people or real products
In a small genetic study of 6 people with multiple chemical sensitivity and 5 controls, every single MCS patient carried at least one rare, homozygous variant in a gene from the SLC "solute carrier" transporter family, compared to only 1 of 5 controls.
Weak evidence.
Caveats
Single unreplicated pilot cohort (n=11 total); at least 8 uncorrected statistical comparisons across four gene groups; no odds ratios or effect sizes reported for any variant; no independent replication cohort tested.
Source: Alcorta & Gomez-Diaz 2025, International Journal of Molecular Sciences Link to this fact
Health effects / Self-reported survey
In this Atlanta sample, women were reported as chemically hypersensitive at roughly 1.75 times the rate of men (about 15.7% of women vs 8.95% of men, wiki arithmetic from the paper's cross-tabulation), a smaller sex skew than the same authors' national survey found (F:M about 4.0).
Weak evidence.
Caveats
Our arithmetic, not stated by the authors; the primary brief gives sample counts of 926 women / 600 men and 71.7/28.3% sensitive, which implies roughly 15.3% vs 9.3% (F:M about 1.6), not the 905/592 denominators behind 1.75; single regional self-report survey.
Source: Caress & Steinemann 2003 (EHP), Environmental Health Perspectives Link to this fact
Health effects / Lab study (cells or chemistry)
BKC aerosol exposure altered secretion of 166 proteins in bronchial epithelial cells (84 up, 82 down); a gene-disease network of the upregulated secreted proteins linked GDF15, MMP1, and VEGFA (each increased two- to three-fold) to atherosclerosis and cardiovascular disease, suggesting inhaled BKC could have a direct, not just stress-mediated, systemic cardiovascular effect.
Weak evidence.
Caveats
This is a novel hypothesis from one cell-culture secretome analysis cross-referenced against disease-association databases (DisGeNET, CTD), not a measured blood biomarker change in an exposed animal or human; the authors describe it as warranting further investigation.
Source: Kim et al. 2025, Ecotoxicology and Environmental Safety Link to this fact
Health effects / Review of other studies
Formaldehyde, an ingredient of candle fragrances with a low boiling point, is released at high concentration during candle burning, but the authors state there is no known mechanism linking formaldehyde to bladder carcinogenesis.
Weak evidence: Association is explicitly postulated, not mechanistic, per the authors' own text.
Source: Adamowicz 2019, Cancer Prevention Research Link to this fact
Health effects / Measured in people or real products
A 2025 global disease-burden model estimates that DEHP exposure from plastics was linked to about 356,000 cardiovascular deaths worldwide in 2018 (about 13.5% of CV deaths among 55-64-year-olds), and about 10.5 million years of life lost.
Weak evidence.
Caveats
A disease-burden model that applies one hazard ratio from a single earlier US cohort (the same group's); that ratio (1.10) is the all-cause estimate in the source cohort, whose CV-specific DEHP estimate was only borderline; assumes causation. Bloomberg Philanthropies (anti-plastics campaign) funded.
Health effects / Review of other studies
A 2004 review in the Journal of Applied Toxicology proposed, as a hypothesis, that parabens in underarm and body care products might contribute to breast cancer, and stated that no causal link is proven.
Weak evidence: Narrative review with no new data; the question is the title; the second author's lab supplies much of the paraben data.
Source: [[src-2004-endocrine-disrupters-estrogenic-chemicals-body-care-cosmetics|Harvey & Darbre 2004]], Journal of Applied Toxicology Link to this fact
Health effects / Review of other studies
Breast cancer researchers reviewing the evidence in 2004 said the link between paraben-containing body care products and breast cancer needed rigorous testing, because tumor detection, cell tests, and rodent studies cannot show human causation.
Weak evidence: Authors' own framing; the review lists Bradford-Hill criteria as a plan, not as applied.
Source: [[src-2004-endocrine-disrupters-estrogenic-chemicals-body-care-cosmetics|Harvey & Darbre 2004]], Journal of Applied Toxicology Link to this fact
Health effects / Review of other studies
Two studies on underarm products and breast cancer disagreed in 2002-2003: one with 813 cases and 793 controls found no association with antiperspirant use, the other, of 437 women already diagnosed, linked heavier use to earlier diagnosis.
Weak evidence: Both secondhand; the second had no cancer-free comparison and measured age at diagnosis, not risk; neither tested parabens.
Source: [[src-2004-endocrine-disrupters-estrogenic-chemicals-body-care-cosmetics|Harvey & Darbre 2004]], Journal of Applied Toxicology Link to this fact
Health effects / Hypothesis
A 2004 review noted that breast tumors are disproportionately found in the upper outer quadrant and left breast and suggested, conditionally, that underarm product use might explain it, with no data presented.
Weak evidence: Conditional suggestion ("if this cannot be explained by … anatomical differences"); not tested in the review.
Source: [[src-2004-endocrine-disrupters-estrogenic-chemicals-body-care-cosmetics|Harvey & Darbre 2004]], Journal of Applied Toxicology Link to this fact
Health effects / Other evidence
Even the author of this review notes that homeopathic consultations may help patients through a caring, time-intensive encounter, which is a context effect and does not show the remedy itself works.
Weak evidence: Author's interpretation of uncontrolled outcome studies, which he says are prone to selection bias.
Source: Ernst 2002, Br J Clin Pharmacol, British Journal of Clinical Pharmacology Link to this fact
Health effects / Other evidence
In a small Swedish clinic sample of 60 women with migraine, 63% (38/60) named odors as a migraine trigger, and 87% of those (33/38) named perfume, followed by car exhaust (45%) and cigarette smoke (42%).
Weak evidence.
Caveats
Recruited specifically to find odor-triggered migraine and told the study was about olfaction, so prevalence is an upper bound (worst case 38/95 = 40%); self-report, no controls, no exposure measurement; does not show perfume causes migraine.
Source: Sjöstrand 2010, Curr Pain Headache Rep, Current Pain and Headache Reports Link to this fact
Health effects / Other evidence
A 2011 study's own closet and car scenarios for dry-cleaned wool (about 50 and 126 ppm if all PCE vaporized) are theoretical ceilings that assume no ventilation, not measured exposure.
Weak evidence: The authors say definitive conclusions need skin-absorption and metabolite data; measured bedroom air in Chao 1998 was far lower; its gram conversions are about 28% low.
Source: Sherlach 2011, Environmental Toxicology and Chemistry Link to this fact
Health effects / Other evidence
The authors argue that placebo effects are real biological and psychological responses to the care encounter, but modest, and call for more trials of open-label placebos; the argument rests on small pilot trials, many from the authors' own group.
Weak evidence: Position paper by leading placebo-research advocates; no data of its own. Contested by the Cochrane view that general placebo effects are not clinically important.
Source: Kaptchuk & Miller 2015, New England Journal of Medicine Link to this fact
Health effects / Measured in people or real products
Cardiovascular death was significantly linked to only one DEHP breakdown product, MEOHP (continuous HR 1.18, 1.04-1.35; top third vs bottom third 1.74, 1.05-2.88); the overall DEHP group was only borderline for cardiovascular death.
Weak evidence: Few cardiovascular deaths per tertile give wide intervals; one metabolite out of several tested, with no correction for multiple comparisons; one cohort.
Source: Trasande, Liu & Bao 2022, Environmental Pollution Link to this fact
Health effects / Other evidence
Healthcare workers' hand-hygiene and surface-disinfection routines are a plausible source of quaternary ammonium skin reactions, and the review says the pandemic increased this exposure, but it presents no pandemic-era incidence data.
Weak evidence: Inference from exposure scale and older case reports; no measured rise in dermatitis is reported.
Source: Okeke 2023, Clinical, Cosmetic and Investigational Dermatology Link to this fact
Health effects / Measured in people or real products
Of the 530 VOCs emitted, 193 appear on California DTSC's Candidate Chemicals List or the EU's ECHA hazard inventory (42 DTSC, 191 ECHA, 40 on both), including neurotoxicants, carcinogens, and reproductive toxicants.
Weak evidence.
Caveats
EWG-authored (advocacy nonprofit that ranks cleaners and licenses EWG VERIFIED to cleaner makers); Skyline Foundation grant; unblinded; List membership is hazard, not risk; ECHA entries include company self-classifications; no dose or health outcome measured.
Health effects / Other evidence
EWG said 1,4-dioxane, a suspected human carcinogen, is a common contaminant of widely used detergent chemicals, and chloroform can escape in fumes from chlorine bleach products.
Weak evidence: Advocacy-group statements with no measurements on this page; 1,4-dioxane is a by-product that does not appear on labels.
Source: EWG press release, Sept. 10, 2012, EWG press release (web page) Link to this fact
Health effects / Other evidence
In rodent studies of a hydrocarbon dry-cleaning solvent (Stoddard Solvent IIC), adrenal tumors appeared in male rats, liver adenomas in female mice were equivocal, and sperm motility fell at 550 milligrams per cubic meter in rats and 2200 in mice.
Weak evidence.
Caveats
Animal data for a related solvent with higher aromatic content (0.58-0.93%) than the 0.1% or less reported for the DC-142 product; the report uses it as a stand-in; current high-flash solvents are not directly tested.
Source: SCDHS 2018 Link to this fact
Health effects / Other evidence
In hamster cheek-pouch studies cited in the CIR hydrogen peroxide report, 30% peroxide given with the carcinogen NNK produced tumors in 23 of 32 animals, with none in controls given either alone; the report's Discussion does not mention this.
Weak evidence: Animal study at 30% peroxide (far above cosmetic use) with a co-administered carcinogen; not evidence of harm at present use levels.
Source: Becker et al. 2024, International Journal of Toxicology Industry-funded Link to this fact
Health effects / Other evidence
The urinary marker of the fragrance-carrier phthalate DEP (MEP), at a median of about 403 ug/g creatinine, showed no link to lower cognitive or motor scores in the Spanish INMA cohort.
Weak evidence: Single cohort; MEP also marks other sources and the fragrance mixture; no product-use data.
Source: [[src-2015-prenatal-exposure-phthalates-neuropsychological-development-during-childhood|Gascon 2015]], International Journal of Hygiene and Environmental Health Link to this fact
Health effects / Other evidence
The same study found no association of parabens, bisphenols (BPA, BPS, BPF), benzophenone-3, triclosan or triclocarban with ADHD-type behavior in 15-year-olds.
Weak evidence.
Caveats
Null in one small cross-sectional sample with one or two spot urines per teen (misclassification biases toward null); absence of association is not proof of safety; none of these is a fragrance ingredient.
Health effects / Measured in people or real products
The study could not test whether maternal thyroid hormones carry the paraben-ADHD link: methylparaben was not associated with ADHD in the 123 women with thyroid data, and preterm birth and birthweight 'mediated' only 20% and 13% of the point estimate with intervals including 1.
Weak evidence: Underpowered subset; a different chemical from the DEHP null in Engel 2018; the authors themselves call the thyroid pattern only 'consistent with' mediation.
Source: Baker 2020, Environment International Link to this fact
Health effects / Other evidence
In the Atlanta survey, 30.2% of the people who called themselves chemically sensitive also reported asthma, against 12.1% of the whole sample.
Weak evidence: Descriptive cross-tabulation only: the brief prints no asthma rate for the non-sensitive group and tests no association; self-reported asthma.
Source: Caress & Steinemann 2004 (AJPH), American Journal of Public Health Link to this fact
Health effects / Other evidence
Among Atlanta adults who reported being chemically sensitive or unsure, about 3 in 10 (29.9%) said it made shopping in stores difficult and 13.5% said they had lost a job because of it.
Weak evidence: Self-report; asked of 'yes' plus 'not sure' respondents, not only the 199 'yes'; causation of job loss not verified.
Source: Caress & Steinemann 2004 (AJPH), American Journal of Public Health Link to this fact
Health effects / Other evidence
Atlanta (12.6%) and California (15.9%) used the same chemical-sensitivity question; the authors call the two 'statistically similar' without printing a test, though a simple two-proportion check (wiki arithmetic, unweighted) puts the 3.3-point gap at about z = 3.3.
Weak evidence: Unweighted check; the California survey was weighted and the Atlanta brief reports no weighting or design effect, so the real gap test is uncertain.
Source: Caress & Steinemann 2004 (AJPH), American Journal of Public Health Link to this fact
Health effects / Other evidence
Nearly half (48.9%) of US adults with asthma in this survey said their asthma began before age 11, and 32.6% said it began after age 20.
Weak evidence: Retrospective recall; percentages computed on 135 not 137; small sample.
Source: Caress & Steinemann 2009 (Toxicol Ind Health), Toxicology and Industrial Health Link to this fact
Health effects / Other evidence
Among adults who knew or suspected a cause of their asthma (59 people), 13.6% (8) named toxic exposure; counted against all 137 asthmatics that is about 6%, and most could not name a cause.
Weak evidence: Self-reported attribution, tiny numerator (8); the abstract words the 13.6% as a share of asthmatics.
Source: Caress & Steinemann 2009 (Toxicol Ind Health), Toxicology and Industrial Health Link to this fact
Health effects / Other evidence
In the same rat study, perfume-exposed animals had higher blood pressure (130 vs 112 mmHg), heart rate (376 vs 352 bpm), cardiac troponin T (3.41 vs 2.06 ng/mL) and creatinine (0.99 vs 0.60 mg/dL) and lung and heart tissue changes on slides.
Weak evidence: Animal only, n = 5; single troponin and creatinine values with large SE; no empty-box or ethanol control; histology unscored; dose unknown relative to human use.
Source: Al-Sowayan 2026, Frontiers in Pharmacology Link to this fact
Health effects / Other evidence
In about 2,700 Barcelona schoolchildren aged 7-11, higher traffic-related air pollution measured at school (elemental carbon, NO2) went with about 7-8% higher parent-reported behavioral difficulty scores per interquartile range, and the pattern held after adjusting for classroom noise.
Weak evidence: Cross-sectional, 39 school-level exposure values, parent-rated only, small effect; not a causal estimate. Air pollution is not fragrance-related.
Source: Forns 2016, Environmental Health Perspectives Link to this fact
Health effects / Other evidence
The Barcelona school study found no association between school traffic air pollution and teacher-rated ADHD symptoms in single-exposure models, and one unexplained inverse estimate for indoor elemental carbon (aMR 0.89, 0.82-0.96) when noise was added.
Weak evidence: Authors state the inverse finding may reflect chance or bias; two different raters scored the two outcomes so they cannot be compared directly.
Source: Forns 2016, Environmental Health Perspectives Link to this fact
Health effects / Animal study
The review's only blue-specific data are animal and cell studies: a rat study of Blue No. 2 found no neurocarcinogenicity, a cell study found Blue No. 1 plus glutamate slowed neurite growth, and a mouse study found slower motor tasks and, in females, more spontaneous 'hyperactive' behavior at high doses of Brilliant Blue FCF.
Weak evidence: Animal and cell results; none is a human finding, and doses and relevance to children are not established. Relayed second-hand, not checked against the primaries.
Health effects / Other evidence
In the olfactory studies the review pooled, children with ADHD stopped from methylphenidate showed no difference from controls in odor threshold or identification in one study (p = 0.345 to 0.855), against a lower threshold in the other (p < 0.004).
Weak evidence: Two small German clinic studies (20 per group; 13-22 per group); the lower-threshold result is not replicated; trait measure on a rose-like odorant, not odor intolerance.
Source: Recarey-Rama 2025, Journal of Psychiatric Research Link to this fact
Health effects / Other evidence
The review's abstract says children on methylphenidate had worse odor discrimination than unmedicated children, but the one study that measured it found higher discrimination in the unmedicated (withdrawal) group than in controls (p = 0.009) and no significant difference from the medicated group (p = 0.068).
Weak evidence: The abstract summary is not supported by its own table; both groups are cross-sectional, different children.
Source: Recarey-Rama 2025, Journal of Psychiatric Research Link to this fact
Health effects / Other evidence
Children with ADHD not on methylphenidate reported less pain than controls (p = 0.015) in a German survey of 260 children, while medicated children did not differ from controls (p = 0.782).
Weak evidence: Single study with a self-constructed parent/child questionnaire; cross-sectional between-group comparison; opposite results in Turkish and US studies cited by the authors.
Source: Recarey-Rama 2025, Journal of Psychiatric Research Link to this fact
Health effects / Other evidence
Two French studies found worse postural control in children with ADHD that improved after about a month of methylphenidate, but a German study with methylphenidate plus atomoxetine did not replicate it.
Weak evidence: Small samples (14 to 38 per group); not an environmental or fragrance finding; mixed medication in the null study.
Source: Recarey-Rama 2025, Journal of Psychiatric Research Link to this fact
Hidden ingredients / Measured in people or real products
Acetaldehyde, a possible human carcinogen (IARC Group 2B), was released by 23 of 42 baby products and was never listed on any label.
Weak evidence: Not quantified; may partly form during 40 C incubation.
Source: Nematollahi 2018, Air Quality, Atmosphere & Health Link to this fact
Hidden ingredients / Other evidence
In 2006 EWG stated that 'the government cannot mandate safety studies of cosmetics, and as a result 89 percent of the ingredients in cosmetics and personal care products have not been adequately assessed for safety,' and described its Skin Deep database as covering 25,000 products.
Weak evidence.
Caveats
An advocacy organization's own unreferenced statistic; the report gives no method or definition of 'adequately assessed', so it should be cited as EWG's claim, not as an established fact.
Source: EWG 2006 Annual Report, EWG annual report (PDF) Link to this fact
Hidden ingredients / Other evidence
GOTS 8.1's list of prohibited hazard statements for general chemical inputs covers carcinogens, mutagens, reproductive toxicants, organ toxicants, and endocrine disruptors but, as printed, not skin (H317) or respiratory (H334) sensitizers, so sensitizing chemicals are only banned by name for dyes.
Weak evidence: Reading of the printed list; other GOTS documents may add restrictions, and certification relies on approved inputs, not this list alone.
Source: GOTS 8.1 (2026) Link to this fact
Hidden ingredients / Other evidence
EWG's own analysis of over 4,000 personal care products found that undisclosed 'fragrance' appeared in 6.4 percentage points more products marketed to Black women than in EWG's 2016 report, which it says equals hundreds more products.
Weak evidence: Advocacy-NGO analysis of its own database, not peer reviewed; the news page gives no statistics or product-selection method.
Source: EWG 2025 (Friedman & Huang), EWG news (web page) Link to this fact
Information, not medical advice. See also: myths we won’t tell you.