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.
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
About half of children's cosmetics in a Danish registry (634 of 1,179, 53.8%) listed perfume or a named fragrance allergen, and a US survey of 533 baby/child personal care products found a closely similar share (255/533, 47.8%; Bonchak 2018); in Danish baby-care products the commonest named allergens were linalool, limonene and benzyl alcohol (the US primary does not report limonene or linalool by name).
Strong evidence.
Caveats
Danish half is primary (Botvid 2023): baby-care products specifically were 38.0% (178/468), the least fragranced category — do not write 'half of baby products' for Denmark. 'Fragranced' there includes products naming only an allergen such as benzyl alcohol (often a preservative). US half is now also primary (Bonchak 2018): 47.8% (255/533) across wipes/diaper care/soap/moisturizer/shampoo/sunscreen — but Bonchak's fragrance count is a ~20-keyword composite that does not report limonene or linalool individually, so the 'top three' allergen list is confirmed only for Denmark. Label counts remain lower bounds.
Source: Sukakul 2024, Acta Dermato-Venereologica Industry-funded Link to this fact
Children and pregnancy / Measured in people or real products
Pregnant women who had used perfume or cologne in the past day had 167% higher urine levels of MEP, the breakdown product of the fragrance solvent diethyl phthalate (DEP), than women who hadn't (177 women, Boston).
Strong evidence.
Caveats
Exposure marker, not health outcome; independently replicated in two further US cohorts with overlapping confidence intervals: Parlett 2013 (2.92x, postpartum, SFF multi-site) and Just 2010 (2.3x, 95% CI 1.6-3.3, pregnant, NYC minority cohort, with a dose-response and a null personal-air DEP association pointing to a dermal exposure route).
Source: Braun 2014, Journal of Exposure Science and Environmental Epidemiology Link to this fact
Children and pregnancy / Measured in people or real products
Synthetic musk fragrance chemicals were found in the breast milk of every one of 39 Massachusetts mothers tested in 2004; the most common, galaxolide (HHCB), was in 97% of them.
Strong evidence: One US state, 2004 samples, n=39; no product-use data; no health outcome.
Source: Reiner 2007, Environmental Science & Technology Link to this fact
Children and pregnancy / Measured in people or real products
Musk scent chemicals used in perfumes, deodorants and detergents turn up in mothers' milk fat; a breastfed baby takes in an estimated ~2 micrograms of galaxolide a day.
Strong evidence.
Caveats
Intake is a model estimate from means of detects; the printed intakes do not reproduce from the stated method. Independently corroborated: Lignell 2008 (N=101, Swedish mothers, single lab) estimated median infant HHCB intake at 1650 ng/day (range 50-6950) using the same milk-intake modeling approach, closely matching this paper's printed 1830 ng/day figure in an unrelated country and cohort.
Source: Reiner 2007, Environmental Science & Technology Link to this fact
Children and pregnancy / Review of other studies
Indoor irritant limits are built on studies of healthy young adults; a 2024 toxicology review found only one controlled irritation study in children (none under age 5) and concluded no evidence-based safety factor for children could be set.
Strong evidence: Absence of data, not evidence of harm; the review lists reasons children could be more or less susceptible (e.g. more stable tear film).
Source: Kleinbeck & Wolkoff 2024, Archives of Toxicology Industry-funded Link to this fact
Children and pregnancy / Measured in people or real products
16.5% of children and adolescents patch tested in 9 population studies had a contact allergy, and in Swedish 16-year-olds fragrance (2.1%) was the second most common allergen after nickel.
Strong evidence: Any allergen, not fragrance only; some adolescent studies read too early and underestimate.
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 three independent prospective birth cohorts. 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 three cohorts are observational and use self-reported product-use frequency, not measured indoor air chemistry. 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. ELSPAC-CZ's asthma outcome is unusually strong methodologically (pediatrician-diagnosed at school age), but that link runs through the wheeze phenotype rather than directly from exposure to asthma. Casas 2013 is the only cohort with genuinely prenatal (rather than early-postnatal) exposure measurement, which strengthens the prenatal-timing evidence specifically, but its own summed cleaning-product-count score was NOT a significant predictor, unlike CHILD's and ELSPAC-CZ's composite scores — an open methodological tension that means 'more products used' is not yet a uniformly replicated exposure metric across all three 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 / Review of other studies
The government scientists who first linked lavender and tea tree oils to breast growth in children agree that four case reports cannot prove the oils caused it, and have called for epidemiological studies.
Strong evidence: Correspondence; the same letter also calls ER-agonist exposure 'substantial evidence of causality'.
Source: Ramsey et al. 2020 (JCEM reply), The Journal of Clinical Endocrinology & Metabolism Link to this fact
Children and pregnancy / Review of other studies
A 2018 US EPA systematic review found robust evidence that two common phthalates, DEHP and DBP, are linked to male reproductive harm (lower sperm quality; shorter anogenital distance in baby boys exposed before birth) at everyday exposure levels.
Strong evidence: Associations graded by protocol; DEHP/DBP are mainly plasticizers, not fragrance ingredients; no meta-analysis.
Source: Radke 2018 (US EPA), Environment International Link to this fact
Children and pregnancy / Measured in people or real products
A perfume ('eau de cologne') marketed for babies listed 16 different fragrance allergens, the most of 1,179 children's products in a Danish registry.
Strong evidence: A single product (the maximum), not typical; mean 0.4-1.8 named allergens per product by category; label presence, not dose.
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
Children and pregnancy / Measured in people or real products
Even products marketed 'fragrance free' for children commonly contain contact allergens: of 52 US pediatric products so labeled in 2013, 42 (80.8%) contained at least one NACDG-tray allergen and 29 (55.8%) contained two or more.
Strong evidence: Label-based; allergens are not broken down by which ones appeared specifically in the 'fragrance free' subgroup beyond the count, and no concentration data exist.
Source: Hamann 2015, Journal of Allergy and Clinical Immunology Link to this fact
Children and pregnancy / Measured in people or real products
Three in four children's cosmetics (295 of 398, 74.1%) on sale in a Brazilian city listed "parfum/fragrance" on the label, including 90% of children's shampoos and 79% of baby wet wipes.
Moderate evidence.
Caveats
Label count only, one city, lower bound. Scope also excludes perfume/cologne, which 65.9% of children in the same city used (Melo 2020). A US survey of a broader category mix of personal-care products (Bonchak 2018, n=533) found a lower fragrance-keyword prevalence (48%), and Denmark's named-allergen tally found 53.8% (Botvid 2023) — country, category mix and label-counting method all move this figure, so 74.1% should not be read as a universal children's-cosmetics rate.
Source: Uber 2024, Jornal de Pediatria (Rio de Janeiro) 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 / Measured in people or real products
Pregnant women who used lotion had 111% higher butyl paraben, a preservative that weakly mimics estrogen.
Moderate evidence: Exposure marker only.
Source: Braun 2014, Journal of Exposure Science and Environmental Epidemiology Link to this fact
Children and pregnancy / Measured in people or real products
In a US study, baby boys whose mothers had higher levels of several phthalates in their urine during pregnancy had a shorter distance between the anus and genitals, a sign of reduced male-hormone action during development in animal studies. A much larger (N=753), purpose-designed prospective follow-up by the same research group (TIDES, Swan 2015) confirmed this specifically for DEHP metabolites (a PVC plasticizer), with a significant, dose-responsive association at about half the original exposure level. It found no association for diethyl phthalate (DEP), the phthalate used in fragrance, nor for the other three phthalates (DBP, BBzP, DiBP) that had appeared linked in the original small study.
Moderate evidence.
Caveats
Swan 2005: 85 mother-son pairs, one urine sample, association. Swan 2015/TIDES (N=753, primary source, reconciled 2026-09-27): DEHP metabolites replicated (P=0.008-0.036); DEP/MEP null (P=0.374/0.953); DBP/BBzP/DiBP also non-significant as continuous associations in this larger cohort. US EPA (Radke 2018) rates DBP/DEHP-AGD moderate and DEP-AGD slight, consistent with this primary. Do not use this study for a fragrance/DEP claim; the replicated component is DEHP, a plasticizer, not a fragrance ingredient.
Source: Swan 2005, Environmental Health Perspectives Link to this fact
Children and pregnancy / Review of other studies
Synthetic musks reach mothers and babies mainly through the skin (cosmetics and clothes washed in scented detergent), not through food.
Moderate evidence.
Caveats
Inferred from absence in sea fish and no nursing-duration effect in newborns' fat; Reiner 2007 reaches the same conclusion. Hutter 2009 (100 Vienna adults, blood + cosmetics-use questionnaire) found cosmetics-use frequency significantly predicted only polycyclic-musk (galaxolide, tonalide) blood levels, not nitro-musk (musk ketone, musk xylene) levels. Lignell 2008 (101 Swedish mothers, milk) replicates this exact split in the matrix that actually reaches the infant: perfume use predicted HHCB, perfumed-laundry-detergent use predicted AHTN, but no product-use variable predicted musk xylene. No study has directly tested a dietary/food route for any musk in any of these populations, so 'not through food' remains an inference from the absence of nitro musks in sea fish (Schmeiser 2001), not a measured food-vs-skin comparison.
Source: Schmeiser 2001, International Journal of Hygiene and Environmental Health Link to this fact
Children and pregnancy / Review of other studies
As of 2019, the evidence that lavender or tea tree oil causes breast growth in young children consisted only of case reports: 11 children described in detail in 4 papers, with no controlled study.
Moderate evidence: Systematic review of case reports; undercounts (one included paper reports ~20 more cases in clinic tallies).
Source: Hawkins 2020, Complementary Therapies in Medicine Industry-funded Link to this fact
Children and pregnancy / Animal study
In the only independent animal experiment on the question, female rats housed with a lavender-oil diffuser from weaning reached puberty about 4.6 days earlier than unexposed rats (33.8 vs 38.4 days), with luteinizing hormone about 35% higher and follicle-stimulating hormone about 45% higher and no difference in body weight.
Moderate evidence: Five rats per group, one species, one sex, a single dose that was never measured in the cage air; no human data. The paper's abstract mislabels which group was exposed how.
Source: Kim & Lim 2022, Journal of Korean Medical Science Link to this fact
Children and pregnancy / Animal study
The effect appeared through breathing the air rather than through skin contact, which matters because the main scientific defense of lavender products is that too little gets through the skin to do anything.
Moderate evidence: Rat study; the inhaled dose was not measured, and no one has measured what a real room diffuser puts into the air either.
Source: Kim & Lim 2022, Journal of Korean Medical Science Link to this fact
Children and pregnancy / Animal study
In the same industry study's one-generation rat screen, the highest linalool dose (800 mg/kg/day, high enough to make the mother rats visibly ill) produced more stillbirths, worse pup survival in the first four days and pups that stayed smaller throughout nursing; the authors call follow-up testing 'mandatory' before this can be dismissed.
Moderate evidence.
Caveats
Only at a maternally toxic dose, orders of magnitude above any human exposure, in a screening study with few litters; the authors attribute it to maternal toxicity. Not a consumer risk claim.
Source: Hareng 2024, Archives of Toxicology Industry-funded Link to this fact
Children and pregnancy / Measured in people or real products
In a Danish/multi-country test of 25 children's cosmetics and cosmetic-toys, all 7 hydro-alcoholic children's fragrance products (5 eau de toilette, 1 eau de parfum, 1 roll-on deodorant) contained the allergen geraniol, and a separate children's toy-cosmetic perfume-blending kit's lilac essence contained cinnamic alcohol at 3.7% — about 4.6x (the paper's abstract states "by a factor of 5") the IFRA guideline of 0.8%.
Moderate evidence.
Caveats
Now sourced from the primary study (Rastogi 1999; n=25 products, Denmark/Germany/England/Sweden, 1997-98) rather than relayed via a review. Single small study, not replicated: strength stays moderate per the grading rule. The geraniol finding is for regular children's fragrance products, not toys; only 1 of 3 toy-perfume-set essences had the elevated cinnamic alcohol — the review's original "cosmetic-toy perfumes" framing conflated the two.
Source: Pastor-Nieto 2021 (Rastogi 1999), Current Treatment Options in Allergy Link to this fact
Children and pregnancy / Animal study
When rats were fed the sunscreen ingredient 4-MBC from before conception through pregnancy and nursing, male offspring reached puberty later and had smaller prostates as adults; the lowest dose that did this was 7 mg/kg/day, and for the related compound 3-BC it was 0.24 mg/kg/day, the lowest dose tested.
Moderate evidence.
Caveats
Long Evans rats, dietary dosing so intake is estimated; tables give direction of change only, no effect sizes or group sizes for most endpoints; female puberty was unaffected; 3-BC effects are non-monotonic and no NOAEL was established.
Children and pregnancy / Animal study
Developmental exposure to 4-MBC changed the activity of estrogen-controlled genes in the adult offspring's uterus, prostate and hypothalamus, erased the normal male-female difference in hypothalamic progesterone-receptor mRNA, and changed how those tissues later responded to an estrogen challenge.
Moderate evidence.
Caveats
Rat only; real-time PCR mRNA endpoints, no protein or functional behavior measured; gene-expression endpoints gave the same lowest effective dose as the classical endpoints, so they did not lower the threshold.
Children and pregnancy / Self-reported survey
In a Brazilian hospital survey, caregivers said two in three children aged 14 and under (182 of 276, median age 4) wore perfume.
Moderate evidence: One Curitiba tertiary-hospital clinic sample, 2015-16; 'perfume' undefined; no frequency, age or sex breakdown; count identical to children's shampoo (possible copy error).
Source: Melo 2020, Revista Paulista de Pediatria Link to this fact
Children and pregnancy / Self-reported survey
A quarter of Brazilian children in a hospital survey (71 of 276) already wore make-up, starting at a median age of 4, usually because the child asked for it (75% of users).
Moderate evidence: One hospital sample; caregiver report; frequency not asked.
Source: Melo 2020, Revista Paulista de Pediatria Link to this fact
Children and pregnancy / Measured in people or real products
In a Danish registry of 1,179 cosmetics marketed for children, more than half (634, 53.8%) listed perfume or a named fragrance allergen, and nearly half (550, 46.6%) named at least one of the 26 EU-listed fragrance allergens.
Moderate evidence.
Caveats
Label tally from a user-scanned consumer-app registry (2015-22), not market-weighted; 'fragranced' includes products naming only benzyl alcohol (often a preservative); sub-threshold allergens not declared.
Children and pregnancy / Measured in people or real products
93% of children's facial-care products in a Danish registry (80 of 86, almost all lip balms) listed fragrance, averaging nearly two named fragrance allergens each.
Moderate evidence: Label data; n=86; registry sample.
Children and pregnancy / Review of other studies
Balsam of Peru, a strong skin sensitizer that the fragrance industry's own standards body (IFRA) had recommended banning, was an ingredient of popular US diaper-rash ointments in the 1990s, applied under occlusion to inflamed infant skin.
Moderate evidence: One clinical commentary citing one 1990 case series (Fisher); current diaper-rash product formulations were not checked for this page.
Source: Scheinman 1999, Journal of the American Academy of Dermatology Link to this fact
Children and pregnancy / Measured in people or real products
In a US label survey of 533 personal care products marketed for babies and children, 48% (255/533) contained a fragrance-category allergen and 55% (294/533) contained at least one of eight screened contact allergens.
Moderate evidence.
Caveats
Single US retail platform (Drugstore.com/Walgreens), one 2018 snapshot; fragrance is a ~20-keyword composite tally, not a per-chemical breakdown; no chemical verification of labels.
Children and pregnancy / Measured in people or real products
Cheaper baby and children's personal care products contain significantly more contact allergens than pricier ones: products with two or more screened allergens averaged $1.39 per ounce versus $4.35 per ounce for products with none.
Moderate evidence.
Caveats
Correlation only, no mechanism tested; a similar but non-significant trend was found in adult moisturizers (Xu 2017), so the effect size and significance may not generalize beyond baby products.
Children and pregnancy / Measured in people or real products
Pregnant women who used perfume in a 48-hour window had 2.3 times higher urinary levels of MEP, the breakdown product of the fragrance solvent diethyl phthalate (DEP), than non-users, in a study of 186 low-income African American and Dominican pregnant women in New York City — independently replicating the same finding in a Boston fertility-clinic cohort (Braun 2014, 167% higher) and a postpartum cohort (Parlett 2013, 2.92x).
Moderate evidence: Exposure marker only, no health outcome; single cohort, cross-sectional; 95% CI 1.6-3.3 overlaps Braun 2014 and Parlett 2013.
Source: Just 2010, Journal of Exposure Science and Environmental Epidemiology Link to this fact
Children and pregnancy / Measured in people or real products
More frequent perfume use tracked higher urinary MEP in pregnant women in a clear dose-response pattern.
Moderate evidence: N=128 subset; exposure marker only, no health outcome.
Source: Just 2010, Journal of Exposure Science and Environmental Epidemiology Link to this fact
Children and pregnancy / Measured in people or real products
In an ordinary primary-school classroom, children were exposed to ultrafine-particle bursts reaching 140,000 particles per cubic centimeter during art activities, the highest classroom particle level measured among the wiki's school-exposure studies — with no health outcome measured.
Moderate evidence.
Caveats
Exposure measurement only; no symptom, lung-function or biomarker data were collected; one school; the specific art-material source was not identified (only 4 of ~30 paints/glues were tested, none containing limonene).
Source: Morawska 2009, Environmental Science & Technology Link to this fact
Children and pregnancy / Measured in people or real products
In a 1999 European lab test, all 7 children's hydro-alcoholic fragrance products (eau de toilette, eau de parfum, roll-on deodorant) contained the allergen geraniol, and a children's toy perfume-blending kit's "lilac essence" contained cinnamic alcohol at 3.7% — about 4.6x (the paper's abstract states "by a factor of 5") the industry's own 0.8% safety guideline.
Moderate evidence.
Caveats
N=25 products total, n=7 hydro-alcoholic products and n=1 toy item for the two headline numbers; single small study (Denmark/Germany/England/Sweden, 1997-98), not replicated for this specific product set.
Children and pregnancy / Measured in people or real products
Everyday children's shampoos, shower gels, creams and lotions rarely contained fragrance-mix allergens — cinnamic alcohol, cinnamic aldehyde and isoeugenol were absent from every sample tested — while the notable allergen exposure was concentrated in perfume-type products and one toy.
Moderate evidence: N=5 shampoos/shower gels, n=4 creams/lotions; small sample.
Children and pregnancy / Measured in people or real products
In a small pilot study of 14 Washington DC childcare facilities, chloroform – a byproduct of the chlorine bleach used to clean – was found in every single air sample, at levels averaging 1.4-1.8 times higher than in a comparable California childcare study.
Moderate evidence: Small unfunded pilot (14 facilities), single-day snapshot, convenience sample; measured no fragrance chemicals at all.
Source: Quirós-Alcalá 2016, Environmental Research Link to this fact
Children and pregnancy / Measured in people or real products
Two no-lye hair relaxer kits marketed for children had the highest measured levels of chemicals banned in EU cosmetics or listed under California's Proposition 65 (DEHP, nonylphenol, o-phenylphenol, diethanolamine) of any products tested in this study.
Moderate evidence: N=3 relaxer kits (2 marketed for children); no health outcome measured in children who used these products.
Children and pregnancy / Measured in people or real products
In a Czech birth cohort of 3,411 children (ELSPAC-CZ), each 1-SD increase in an 18-product household chemical exposure score measured at 6 months raised the odds of intermediate-onset transient wheeze (adjusted OR 1.27), early-onset persistent wheeze (adjusted OR 1.36) and intermediate-onset persistent wheeze (adjusted OR 1.23) through age 5, and those persistent wheeze phenotypes carried 5-8x higher odds of a doctor-diagnosed asthma by age 7 (pediatrician records, not self-report).
Moderate evidence.
Caveats
Single prospective cohort; exposure and wheeze through age 5 are maternal self-report (only the school-age asthma outcome is medically ascertained); the asthma link runs through the wheeze phenotype, not directly from exposure to asthma, and the paper's own direct exposure-to-asthma model was underpowered. Independently replicates the Canadian CHILD cohort (Parks 2020), which together raises the combined wheeze/asthma claim to strong (see regrade on src-2024-cleaning-products-chemistry-indoor-air-quality-health).
Source: Mikeš 2019, Science of the Total Environment Link to this fact
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 / Self-reported survey
Teenage girls reported chemical sensitivity about twice as often as boys (20.6% vs 9.9%), and being female, being sensitive to noise, or having probable anxiety each roughly doubled the odds of reporting it.
Moderate evidence: Logistic regression with low explanatory power (Nagelkerke R2=0.092); only modeled for the general-CS outcome.
Source: Andersson 2008, International Journal of Hygiene and Environmental Health Link to this fact
Children and pregnancy / Measured in people or real products
In a US EPA/CDC study of 33 breastfeeding women, phthalate breakdown products were detected in fewer than 10% of breast milk samples and were essentially absent from saliva, even though the same women had detectable phthalate metabolites in nearly all of their urine samples.
Moderate evidence.
Caveats
Small pilot study (n=33, two visits); the metabolites reported for milk are four DEHP-derived oxidative metabolites, not MEP (the fragrance phthalate DEP's metabolite), which was analyzed only in urine.
Source: Hines 2009, Environmental Health Perspectives Link to this fact
Children and pregnancy / Measured in people or real products
In a large US study of 753 pregnant women and their newborns, higher first-trimester urinary levels of DEHP (a plasticizer found in PVC, food packaging and some medical devices, not primarily a fragrance ingredient) were associated with a shorter anogenital distance in baby boys, a sign of reduced male-hormone action during development, replicating an earlier smaller study at about half the exposure level.
Moderate evidence.
Caveats
Single first-trimester urine sample per mother; association, not proof of causation; cohort was largely White, college-educated and married, limiting generalizability; effect sizes were smaller than in the earlier, smaller cohort (Swan 2005).
Children and pregnancy / Measured in people or real products
In the same large study (N=753), urinary levels of diethyl phthalate (DEP), the phthalate most strongly and consistently tied to perfume and fragranced personal-care product use, showed no association with anogenital distance in baby boys — the largest and best-controlled human test yet of this specific fragrance-phthalate reproductive claim, in the same boys where DEHP did show an effect.
Moderate evidence.
Caveats
A null result in one (albeit the largest) cohort cannot fully rule out an effect at higher exposure levels than this population had; two smaller medium-confidence cohorts (Odense, SELMA) were also null, per US EPA's review.
Children and pregnancy / Review of other studies
The developing fetal and infant brain is far more vulnerable to industrial-chemical injury than the adult brain: the placenta is not an effective barrier to most industrial chemicals, the blood-brain barrier is not fully formed until about 6 months after birth, and lipophilic persistent chemicals concentrate in breast milk at up to 100-fold the mother's bodyweight-adjusted exposure.
Moderate evidence.
Caveats
General toxicological vulnerability argument for industrial chemicals (lead, methylmercury, PCBs, arsenic, toluene are the paper's 5 confirmed causes); does not measure or name any fragrance ingredient. Should not be cited as fragrance-specific evidence.
Source: Grandjean & Landrigan 2006, Lancet Link to this fact
Children and pregnancy / Measured in people or real products
In 101 Swedish first-time mothers tested over seven years, women who used perfume once a week or more had significantly higher levels of the musk chemical galaxolide (HHCB) in their breast milk than women who used it less often.
Moderate evidence: Product-use data from a N=44 subset; cross-sectional association, not an intervention; adjusted for sampling year.
Source: Lignell 2008, Environmental Science & Technology Link to this fact
Children and pregnancy / Measured in people or real products
Mothers who used perfumed laundry detergent had significantly higher levels of the musk chemical tonalide (AHTN) in their breast milk than mothers who used unscented detergent.
Moderate evidence: Product-use data from a N=44 subset; cross-sectional association, not an intervention; adjusted for sampling year.
Source: Lignell 2008, Environmental Science & Technology Link to this fact
Children and pregnancy / Measured in people or real products
In a national Canadian survey of 98 baby care products, diaper cream — not fragrance — was the largest single modeled source of infant dermal DEP exposure, contributing about half of babies' modeled total.
Moderate evidence: Exposure model uses non-Canada-specific consumer-use-pattern data and a fixed 5% skin-absorption assumption for all phthalates; it is a modeled dose, not a measured biomarker.
Source: Koniecki 2011, Environmental Research Link to this fact
Children and pregnancy / Measured in people or real products
About half of children's diaper-rash creams (13 of 28) and a third of children's sunscreens (10 of 29) listed fragrance.
Weak evidence.
Caveats
Small category counts; label count only. Sunscreen share is market-specific: 64.9% (87/134) of Danish children's sunscreens and sun sprays listed fragrance or a named allergen (Botvid 2023), so 'a third of sunscreens' should not be generalized beyond Brazil; diaper creams were not reported separately in Denmark.
Source: Uber 2024, Jornal de Pediatria (Rio de Janeiro) Link to this fact
Children and pregnancy / Measured in people or real products
In 130 Danish and Finnish mothers, phthalate breakdown products were reported in essentially every breast milk sample (95-100% for each of the six measured) — but an independent, more contamination-controlled US study (Hines 2009) found the analogous class of monoester phthalate metabolites in under 10% of milk samples from a separate cohort, and declined to report its own milk hydrolytic-monoester data (which would include MEP) as likely contamination-inflated.
Weak evidence.
Caveats
1997-2001 samples; composite home-collected milk; phosphoric acid was not added at collection 'due to logistics' (this page's own Methods/limitations), a known contamination risk for hydrolytic monoesters. Hines 2009 (EPA/CDC, tighter contamination controls) found the analogous metabolite class in <10% of milk samples and withheld its own milk hydrolytic-monoester data on contamination grounds. US EPA systematic review (Radke 2018) separately excluded this study's milk data as a critically deficient exposure matrix.
Source: Main 2006, Environmental Health Perspectives Link to this fact
Children and pregnancy / Measured in people or real products
Baby boys whose mothers' milk contained more dibutyl phthalate had slightly lower free testosterone at 3 months (about 15% lower per 10-fold rise). For diethyl phthalate, the fragrance phthalate, the link was with higher SHBG, and its free-testosterone trend was not significant. These are correlations in 96 boys, not proof of harm.
Weak evidence.
Caveats
MBP–free T r = −0.22 (p = 0.033); mEP–free T r = −0.19 (p = 0.07, NS). US EPA review excluded this study (breast milk critically deficient as an exposure matrix for short-chain phthalates) and rated infant-testosterone evidence indeterminate (Lin 2011: MEP r = −0.10). 46% of Danish mothers used breast pumps.
Source: Main 2006, Environmental Health Perspectives Link to this fact
Children and pregnancy / Measured in people or real products
In one early, small US study, boys in the highest phthalate group had about 4 to 10 times the odds (3.8-10.2) of a shorter-than-expected anogenital distance than the lowest group, depending on the phthalate. A larger (N=753) follow-up by the same group found much smaller effect sizes for the one phthalate class (DEHP) that replicated, and did not test comparable categorical odds ratios.
Weak evidence.
Caveats
Single small cohort with very wide CIs (MEP OR 3.8, 1.03-13.9); US EPA rated this cohort's AGD data (extended n=106) low confidence. The DEP (MEP) part did not replicate in three larger cohorts, including the same group's own N=753 TIDES follow-up (Swan 2015), which also found smaller continuous effect sizes for the metabolites that did replicate (DEHP: beta -1.12 to -1.43 in TIDES vs -3.50 to -5.13 in this cohort, per Swan 2015's Discussion), consistent with lower current-day exposure. Quote as one small study's result only; prefer the EPA review or Swan 2015 for general claims.
Source: Swan 2005, Environmental Health Perspectives Link to this fact
Children and pregnancy / Self-reported survey
In a US survey, parents reported that 7 in 10 children aged 12 and under (219 of 312) had used makeup or body products such as face paint, glitter, nail polish or body spray, including more than half of children aged 3 or younger (48 of 84).
Weak evidence.
Caveats
207 self-selected parents recruited mostly online in NYC/Boston/Houston; not nationally representative; ~60% of raw responses excluded as spam/fraud. Partial external check: in a Brazilian clinic survey (Melo 2020) per-category color-cosmetic rates matched Medley's (lipstick 18.8% vs lip ≈21%, nail 22.4% vs ≈22%), but the 70% total is driven by body products (face paint, glitter, bath bombs) that Melo did not ask about, and Melo found make-up in only ≈3% of infants, so the under-3 figure reflects body products, not make-up.
Source: Medley 2023 Link to this fact
Children and pregnancy / Self-reported survey
Among US children who used makeup or body products, about 1 in 8 used them daily, about 1 in 5 wore them for 8 hours or more, and about 1 in 3 had swallowed some in the past year.
Weak evidence: Parent report for 217 child users; ingestion differed sharply by ethnicity (41% vs 11%), possibly a question-wording effect.
Source: Medley 2023 Link to this fact
Children and pregnancy / Self-reported survey
Most US children who use makeup also use products made for adults: only about a third (36%) used mostly children's products.
Weak evidence.
Caveats
Parent estimate of product share; small non-representative sample. Applies to makeup only: for cleansers, a Brazilian clinic survey (Melo 2020) found the majority used children's products (children's soap 56.5%, children's shampoo 65.9%; adult soap 37.3%, adult shampoo 27.2%, rising with age), so do not write 'most children use adult products' generally.
Source: Medley 2023 Link to this fact
Children and pregnancy / Self-reported survey
In a US survey, boys and girls who used makeup or body products used fragrance products (perfume, cologne, body spray) at the same rate, about 31%.
Weak evidence.
Caveats
Scent-purpose products only; cleansers excluded, so not a fragrance-exposure prevalence. Indirect support for sex parity: in Melo 2020 (Brazil, 182/276 perfume users, 126 girls) at least 56/150 boys (≥37%) used perfume, so perfume is not a girls-only product; but the Brazilian level (66% of all children) is 3x the US level (≈21%), so the ~31% figure must not be generalized.
Source: Medley 2023 Link to this fact
Children and pregnancy / Self-reported survey
The only population study of lavender and tea tree oils and hormone problems in children (556 US children) was too small to rule out a risk: regularly exposed children had 2.8 times the rate of endocrine diagnoses, with a 95% confidence interval from 0.35 to 22 times.
Weak evidence: Not statistically significant; parent-reported diagnoses; self-selected natural-product users; 9 events. Supports 'not ruled out', not 'causes'.
Source: Hawkins 2021, International Journal of Pediatrics and Adolescent Medicine Industry-funded Link to this fact
Children and pregnancy / Measured in people or real products
In 2007, US government (NIEHS) scientists described three boys aged 4–10 who developed breast tissue while using products containing lavender oil or lavender and tea tree oil (a homemade balm, hair gel and shampoo, soap and lotions); in each case it went away within months of stopping the products.
Weak evidence: 3 case reports, dechallenge only, no rechallenge, products not analyzed; causation contested (BASF guideline tests negative for linalool/linalyl acetate; Braunstein 2023 review).
Source: Henley 2007, New England Journal of Medicine Link to this fact
Children and pregnancy / Review of other studies
In the reported cases, children had been using lavender-scented products regularly (violet-water colognes, shampoos, soaps, baby bath, lotions) or sat beside a classroom diffuser, and breast growth went away after the products were stopped; early breast growth in children often goes away on its own, so this does not prove cause.
Weak evidence.
Caveats
Case reports with dechallenge only; no comparison group; at least one of the violet-water colognes declared and contained no essential oil by an industry analysis (Giroux & Orjubin 2020). Linklater 2015's own transient alpha-fetoprotein/prolactin elevation resolved on its own over the same 12 months, for an unrelated physiological reason (infant liver immaturity) the authors themselves cite — a concrete illustration, from inside this same case, that concurrent findings can normalize without being caused by the product change.
Source: Hawkins 2020, Complementary Therapies in Medicine Industry-funded Link to this fact
Children and pregnancy / Measured in people or real products
Four prepubertal children (three girls with early breast development and one boy with breast growth) whose doctors recorded continuous use of products they identified as containing lavender saw the breast tissue disappear within three to six months of stopping the product.
Weak evidence.
Caveats
Four uncontrolled case reports, dechallenge only, no product analysis by the authors and no chemical measured in any child; both conditions can resolve spontaneously. An essential-oil industry analysis later reported the boy's violet-water cologne declared and contained no essential oil (DEP, alpha-isomethyl ionone and azo dyes instead), and one girl's baby bath only 'very low' lavender oil (unquantified).
Source: Ramsey 2019, The Journal of Clinical Endocrinology & Metabolism Link to this fact
Children and pregnancy / Self-reported survey
At one Miami children's hospital, 16 of the 24 children seen over seven years for unexplained early breast growth had been using lavender-scented products; 14 of the 16 were Hispanic and the products were violet-water colognes of a kind often applied to babies.
Weak evidence.
Caveats
Clinic case tally with no unexposed comparison group and no use-prevalence denominator; a clinic aware of the lavender hypothesis will ask about lavender; one violet-water cologne from this clinic's case reports declared and contained no essential oil by an industry analysis. Diaz 2016 (2015, same hospital, corresponding author Alejandro Diaz also a co-author here) reported 3 boys with the same outcome in the years just before this tally's window; those 3 cases are almost certainly a subset of this 16/24 figure, not additional to it, so this figure and Diaz 2016 should never be added together.
Source: Ramsey 2019, The Journal of Clinical Endocrinology & Metabolism Link to this fact
Children and pregnancy / Measured in people or real products
One of the four children had never used a lavender product at all: she sat beside a classroom lavender oil diffuser that ran all day for a year, and her breast tissue regressed three months after the diffuser exposure stopped.
Weak evidence: Single case report, no air measurement was made in the classroom, and measured indoor terpene levels elsewhere are far below the concentrations that were active in the cell assays.
Source: Ramsey 2019, The Journal of Clinical Endocrinology & Metabolism Link to this fact
Children and pregnancy / Measured in people or real products
In the same 2018 NGO test, a children's shampoo had 24 unlabeled chemicals flagged for health hazards (17 on the fragrance-industry list), and a baby shampoo had 6.
Weak evidence: Counts, not amounts; single samples; not peer reviewed; not a risk ranking.
Source: BCPP 2018 Link to this fact
Children and pregnancy / Measured in people or real products
In a Danish–Finnish study (hormones measured in 96 of 130 baby boys), some phthalates in mothers' breast milk went with hormone changes at 3 months that point to weaker male-hormone action (higher SHBG; lower free testosterone for dibutyl phthalate only).
Weak evidence.
Caveats
Association; hormones in 96 boys; mEP (DEP) free-T link not significant (p = 0.07); 46% of Danish mothers used breast pumps; US EPA review excluded this study (milk critically deficient as exposure matrix) and rated infant testosterone indeterminate. Cite the primary, not the thesis, which inverted the direction.
Source: Main 2006 Link to this fact
Children and pregnancy / Self-reported survey
Children's lipstick, nail polish and eyeshadow use was about the same in a Brazilian hospital survey and a US parent survey (roughly 19-22%, 22% and 11-13%), but perfume use was three times higher in Brazil (66% vs about 21%).
Weak evidence.
Caveats
Our cross-study arithmetic (Medley per-user rates re-based to all 312 children); different definitions ('perfume' vs 'fragrance products primarily for children'), ages (<=14 vs <=12) and sampling.
Source: Melo 2020, Revista Paulista de Pediatria Link to this fact
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 / Measured in people or real products
Three more boys (ages 9-11) developed breast tissue while using lavender-labeled products, a shampoo or an 'agua de violetas' cologne sprayed on by a parent since early childhood; in each case it resolved within about 4 months of stopping the product.
Weak evidence.
Caveats
Three uncontrolled case reports, dechallenge only, no rechallenge; same hospital and a shared corresponding author (Alejandro Diaz) as Ramsey 2019's later clinic tally, so this is not an independent replication of the case count.
Source: Diaz 2016, Journal of Pediatric Endocrinology and Metabolism Link to this fact
Children and pregnancy / Measured in people or real products
A 14-month-old girl in Melbourne, Australia developed breast tissue while being given five different lavender-scented infant products every day (wipes, shampoo, body wash, cream and lotion); it went away after the products were stopped, and this case has no connection to the better-known United States case series.
Weak evidence.
Caveats
One case report (letter to the editor), dechallenge only, no rechallenge, no product testing; the exposure was identified only after the family saw a documentary about this exact link, not through routine clinical questioning.
Source: Linklater & Hewitt 2015, Journal of Paediatrics and Child Health Link to this fact
Information, not medical advice. See also: myths we won’t tell you.