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.
Health effects / Government agency
As of 1998, EPA's own environmental-health office stated that certain types of childhood cancer were increasing but the causes were largely unknown, and that the agency lacked a reliable basis to determine whether most untested high-production-volume industrial chemicals were safe or unsafe for children.
Moderate evidence.
Caveats
A general statement about data gaps as of 1998, not a study establishing or ruling out any specific chemical-childhood-cancer link; the paper explicitly states EPA does not know how many, if any, childhood cancers are caused by these exposures.
Source: Goldman 1998, Environmental Health Perspectives Link to this fact
Health effects / Other evidence
The WHO-UNEP 2012 report's claim that the rise in autism spectrum disorder (ASD) prevalence is at least partly caused by environmental factors, including endocrine-disrupting chemicals, rests on only two citations (from 1976 and 2007); separate, non-industry-affiliated research attributes much of the reported increase in ASD prevalence to changes in diagnostic criteria, broader case ascertainment, and diagnostic substitution (children previously diagnosed with intellectual disability now diagnosed with ASD) rather than to any confirmed environmental cause.
Moderate evidence.
Caveats
This does not establish that endocrine-disrupting chemicals play no role in ASD, only that the WHO-UNEP report's specific citations for an environmental/EDC contribution are thin; no causal chemical-to-autism claim is made or implied here.
Source: Lamb et al. 2014, Regulatory Toxicology and Pharmacology Industry-funded Link to this fact
Health effects / Review of other studies
A 1950s-70s antiseptic called hexachlorophene showed how a chemical that binds tightly to the skin's outer dead layer can be both protective and dangerous: routine hexachlorophene baths cut newborn staph-infection admissions from about 6.5% to 0.6%, but when 18 French children were accidentally exposed to 6% hexachlorophene talc in 1972, four died and others developed permanent neurological damage from the same skin-binding property letting the chemical build up to toxic levels.
Moderate evidence.
Caveats
Historical case-series data as reported in a 2018 review citing 1950s-70s primary sources; the review does not re-verify the original studies' methods, and the toxic exposure was accidental overapplication (6% in talc powder to skin, some broken), not typical consumer use.
Source: Li, Cary & Maibach 2018, Archives of Dermatological Research Industry-funded Link to this fact
Health effects / Other evidence
Camphor swallowed above about 50 mg/kg causes vomiting, convulsions, and hallucinations; 50 mg/kg by a pregnant woman caused fetal death and 700 mg killed children, while the flavor-use estimate is only about 3 ug/kg/day, roughly 100,000-fold below a plasma level a survivor reached.
Moderate evidence: Medicinal-camphor poisoning reports, few cases; flavor exposure is far below these doses; the 100,000x plasma comparison is the panel's estimate.
Source: Adams 1996, Food and Chemical Toxicology Industry-funded Link to this fact
Health effects / Other evidence
For 14 conditions, including allergic rhinitis, ADHD in children, fibromyalgia, and rheumatoid arthritis, some studies reported homeopathy beat placebo, but NHMRC judged them unreliable because of poor quality, too few participants, or both.
Moderate evidence: The paper says these results would need confirming by well-designed studies with adequate numbers; it does not say they are false.
Source: NHMRC 2015 Information Paper on the effectiveness of homeopathy (CAM02A) Link to this fact
Health effects / Other evidence
NHMRC says it could not separate individualized from clinical homeopathy because most reviews did not analyze them separately, and that most studies used clinical homeopathy; only for children's diarrhea was the evidence split.
Moderate evidence: A limitation the paper itself states; classical individualized homeopathy is therefore under-tested in this review.
Source: NHMRC 2015 Information Paper on the effectiveness of homeopathy (CAM02A) Link to this fact
Health effects / Other evidence
EFSA's 2015 estimate for the highest-exposed toddlers eating polysorbate-containing foods was 24.5 mg/kg body weight a day, just under the 25 mg/kg safe-intake limit, but that is the mildest of its three high-exposure scenarios: in the regulatory-maximum scenario the high-end (95th percentile) exposure exceeds the limit in every age group (up to 63.7 mg/kg a day in children), and in the brand-loyal scenario in every age group except adolescents (up to 57.5).
Moderate evidence.
Caveats
Modeled scenarios, not measured intake. Usage data were missing for three food categories, and polysorbates from cosmetics, personal care products, textiles and pharmaceuticals were not counted, so true exposure could be higher.
Source: EFSA Panel (2015), abstract only, EFSA Journal Link to this fact
Health effects / Government agency
EFSA's worst-case estimate of ethylene oxide intake from polysorbate additives is 12.7 ng per kg body weight a day (children, maximum permitted use, impurity at the EU limit of 0.2 mg per kg), giving a margin of exposure of at least 1.1 million that EFSA called low risk.
Moderate evidence.
Caveats
A model at the specification limit, not measured contamination. Margin built on an oral equivalent converted from inhalation studies; the appendix does not show the full conversion (about 5.6-fold factor unexplained). Ethylene oxide is carcinogenic to humans; this is the dose estimate only.
Source: EFSA ANS Panel (2015), full opinion, EFSA Journal Link to this fact
Health effects / Review of other studies
The authors of a 2015 systematic review could not combine the 11 phthalate neurodevelopment studies statistically because the studies measured different phthalates at different times with different tests, so no single phthalate or exposure level could be named as the main risk.
Moderate evidence: This is a limitation of 2015-era literature (search ended Feb 2014); later cohorts and meta-analyses exist.
Source: [[src-2015-phthalate-exposure-childrens-neurodevelopment-systematic|Ejaredar 2015]], Environmental Research Link to this fact
Health effects / Review of other studies
In the best-known example the authors cite, children of Norwegian mothers in the top fifth of DEHP exposure had almost 3 times the odds of an ADHD diagnosis (OR 2.99, 95% CI 1.47-5.49), and in a New York cohort the highest quarter of prenatal DBP exposure had IQ about 7 points lower than the lowest.
Moderate evidence.
Caveats
Numbers relayed from the primary cohorts (Engel 2018; Factor-Litvak 2014), not recalculated; DEHP and DBP come mainly from food, plastics and medical products, not fragrance; observational associations.
Source: Engel 2021, American Journal of Public Health Link to this fact
Health effects / Measured in people or real products
In 1,491 U.S. children aged 6-15 (NHANES 2001-2004), higher urine levels of DEHP breakdown products (a plastics and food-contact phthalate) went with about twice the odds of a parent-reported ADD diagnosis per 10-fold increase (OR 2.1, 95% CI 1.1-3.9).
Moderate evidence: Cross-sectional, one spot urine, parent-reported lifetime diagnosis, no multiplicity correction, medication not considered; association only, reverse causation possible.
Source: Chopra 2014 (NHANES), Environmental Research Link to this fact
Health effects / Review of other studies
For lead, a larger meta-analysis rated 'moderate' certainty that exposure is associated with ADHD diagnosis in children (odds ratio about 3.4), and a separate systematic review found 12 of 17 studies positive.
Moderate evidence: Observational designs; both reviews overlap in some primary studies; odds ratio taken from the scoping review's table (90% CI 2.66-4.12); lead is not a fragrance ingredient.
Source: Moore 2022 Link to this fact
Health effects / Other evidence
Maternal and child urine concentrations of phthalate metabolites were not correlated in this Taiwanese cohort (mothers had higher MEP and MnBP than their children; children higher MEHP), and 20 of 300 outcome estimates reached p<0.05 with no multiplicity correction, so a single spot-urine design cannot say which period matters.
Moderate evidence: Descriptive observation from one cohort; only 98 children had urine.
Source: Huang 2024, Toxics Link to this fact
Health effects / Other evidence
The average effect in this trial was about 0.18 standard deviations, which the authors put at roughly 10% of the gap between children with ADHD and those without; it was measured in children from the general population, not children with ADHD.
Moderate evidence: Authors' framing; GHA is a composite not validated against clinical impairment (EFSA).
Health effects / Other evidence
A 2007 systematic review pooled 102 surveys of 171,756 children and adolescents (1978-2005) and found about 5.3% (95% CI 5.0-5.6%) met ADHD criteria, with large differences between studies.
Moderate evidence.
Caveats
Pooled survey point prevalence of diagnostic criteria; significant heterogeneity, no publication-bias test or quality scoring; 1978-2005 only; four of five authors disclose ADHD-drug industry ties, funders reported no role.
Source: Polanczyk 2007, American Journal of Psychiatry Industry-funded Link to this fact
Health effects / Review of other studies
The review found sensory problems in ADHD to be measured almost entirely by parent report, and noted that parents of these children often have depression or anxiety and that whether this colors their ratings has not been studied.
Moderate evidence: Author's own caveat; no data on the size of any reporting bias.
Source: Ghanizadeh 2011, Psychiatry Investigation Link to this fact
Health effects / Other evidence
A 2012 meta-analysis of 20 double-blind challenge studies (794 children) found synthetic food colors went with a small increase in parent-rated ADHD-type symptoms (standardized effect 0.18, 95% CI 0.08 to 0.29), shrinking to 0.12 (0.01 to 0.23) after adjusting for possible publication bias.
Moderate evidence.
Caveats
Mostly small, old trials on children preselected as diet responders; heterogeneity moderate (I2 52%); funded by an industry-supported institute and the National Confectioners Association; food colors are not fragrance ingredients.
Source: Nigg 2012 Industry-funded Link to this fact
Health effects / Other evidence
In the same meta-analysis, teacher and observer ratings (10 studies, 323 children) showed no reliable overall effect of food colors (0.07, 95% CI -0.03 to 0.18), and the parent-rated effect was not significant in studies using only FDA-approved colors (13 studies, 0.13, -0.04 to 0.30).
Moderate evidence: Small pooled samples; only one small US-color study used valid measures in non-preselected children; industry-supported funding.
Source: Nigg 2012 Industry-funded Link to this fact
Health effects / Other evidence
A 2013 meta-analysis of 33 studies (10,232 children and adolescents) found a small association between lead exposure and ADHD symptoms: inattention r about .16 (95% CI .12-.20, 27 studies) and hyperactivity/impulsivity r about .13 (.09-.16, 23 studies).
Moderate evidence: Observational studies only; heterogeneity I2 71% (inattention) and 50% (hyperactivity/impulsivity); causation not established.
Source: Goodlad 2013, Clinical Psychology Review Link to this fact
Health effects / Review of other studies
The review says lead is the one ADHD-linked chemical exposure whose associations are unlikely to be fully explained by residual confounding, but still grades it as risk factor not proven causal, and advises reducing toxin exposure for children.
Moderate evidence: Lead is not a fragrance ingredient; the review is narrative; the 'unlikely confounded' view is the authors' reasoning, not a pooled adjusted estimate.
Source: Thapar 2013, Journal of Child Psychology and Psychiatry Link to this fact
Health effects / Other evidence
The rise in diagnosed and treated ADHD that US, UK and Canadian administrative data show is, in the authors' reading of this meta-regression, probably awareness and access to services rather than more children meeting criteria; they say a change in clinical practice cannot be ruled out and that this inference is indirect.
Moderate evidence: Inference from flat community estimates, not a direct test of why diagnoses rose; flat prevalence says nothing about causes in individual children.
Source: Polanczyk 2014, International Journal of Epidemiology Link to this fact
Health effects / Other evidence
Traffic air pollution at school was associated with slower cognitive growth in children, but the paper is observational and does not show that traffic pollution causes lower cognitive ability.
Moderate evidence: Authors write 'demonstrated' and 'strong support', while conceding residual confounding could not be discarded completely.
Source: Sunyer 2015 (BREATHE, Barcelona), PLOS Medicine Link to this fact
Health effects / Review of other studies
A US EPA meta-analysis of child ADHD studies found that children with higher blood lead had about 3 to 4 times the odds of ADHD (odds ratio 3.08 to 4.06 depending on whether text or table is read), graded moderate certainty.
Moderate evidence: Crude observational pool with I2 96 to 99%; several comparisons per study; probable publication bias; text and Table 1 numbers differ; lead is not a fragrance ingredient.
Source: Nilsen and Tulve 2020, Environmental Research Link to this fact
Health effects / Other evidence
A 2022 review that searched PubMed (2000-2022) for studies of blue food dyes (Blue No. 1 and No. 2) and ADHD in children included only four papers, none testing a blue dye alone; the human evidence it relies on is about dye mixtures and restriction diets, and the authors say blue-dye research in children is very limited.
Moderate evidence: Description of what the review found, not evidence on blue dyes; the search was narrow (4 of 20 hits kept) and the review is a low-rigor Cureus paper. Food dyes are not fragrance.
Health effects / Other evidence
Among US children with current ADHD in 2022, about 3 in 4 (77.9%) had another diagnosed condition, most often behavioral or conduct problems (44.1%), anxiety (39.1%) or learning disability (36.5%); 14.4% had autism.
Moderate evidence: Parent report; co-occurrence only, no direction or cause implied.
Source: Danielson 2024 (NSCH 2022), Journal of Clinical Child & Adolescent Psychology Link to this fact
Health effects / Other evidence
A 2025 systematic review of European children and adolescents with ADHD on methylphenidate found 7 eligible studies (2007-2016) and none of them examined genetic variants linked to sensory differences.
Moderate evidence: Absence of studies within a narrow filter (European only, methylphenidate, under 18, English, 2000-2024); not evidence that no genetic link exists.
Source: Recarey-Rama 2025, Journal of Psychiatric Research Link to this fact
Information, not medical advice. See also: myths we won’t tell you.