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.
Hidden ingredients / Measured in people or real products
When researchers tested 25 best-selling US laundry, cleaning, personal-care, and air-freshener products, they found 133 different chemicals released into the air, but only 1 of them was listed on any product label.
Moderate evidence: Single headspace sample per product; VOC counts depend on detection threshold.
Source: Steinemann 2011, Environmental Impact Assessment Review Link to this fact
Hidden ingredients / Measured in people or real products
In 2018, testing commissioned by Breast Cancer Prevention Partners of 25 personal care and 7 cleaning products found chemicals flagged for cancer, hormone disruption, respiratory, or developmental hazards that were not on the label; 99 of the 124 were on the fragrance industry's own ingredient list.
Moderate evidence: Not peer reviewed; labs, detection limits, and concentrations not reported; hazard = database flag; IFRA list includes multifunctional solvents/preservatives.
Source: BCPP 2018 Link to this fact
Hidden ingredients / Measured in people or real products
Di(2-ethylhexyl) phthalate (DEHP), a plasticizer used to make nail polish more flexible and durable, was the most abundant of six phthalates measured on silicone wristbands in all 10 nail salons tested (median 391.80 ng/g-wristband), with diethyl phthalate (DEP) second highest (median 154.4 ng/g-wristband) — but the paper never discusses what produces its measured DEP, unlike its explicit attribution of DEHP to nail polish and d-limonene to cleaning/fragrance products.
Moderate evidence.
Caveats
Small sample (n=10 for phthalates); wristband measurement is a sorbed dose, not a direct air concentration; the paper's own figures and Discussion text mislabel this unit as ppb instead of the Methods/footnote's ng/g-wristband, an internal inconsistency in the published article.
Source: Han et al. 2022 Link to this fact
Hidden ingredients / Other evidence
The workers were challenged with commercial cleaning products that contained mixtures of irritants and possible sensitizers, so the authors could not formally identify which ingredient caused each reaction.
Moderate evidence: Authors' own limitation statement; they infer QACs from known asthma-hazard predictions (asthma hazard index 0.81-0.95), which is a model score, not a test of the product.
Hidden ingredients / Measured in people or real products
The chamber test detected 530 distinct VOCs from 30 cleaning products and air fresheners, and only 17% of them appear in the cleaning industry association's ingredient database (American Cleaning Institute); 23 of 30 products were not fragrance-free and 7 of those listed just 'fragrance'.
Moderate evidence.
Caveats
EWG-authored (advocacy nonprofit that ranks cleaners and licenses EWG VERIFIED to cleaner makers); Skyline Foundation grant; unblinded; Detection of a chemical in chamber air does not show it was an intentional ingredient; some are impurities, by-products or sampling artifacts; 71% of VOCs were found in a single product.
Hidden ingredients / Other evidence
EWG Verified cleaning products must disclose every intentionally added fragrance ingredient publicly down to 0.01 percent, which no US federal rule requires of household cleaners.
Moderate evidence.
Caveats
Applies only to products that opt in and are licensed; the document states requirements, not compliance rates; amounts of ingredients are not disclosed. The comparison with US law relies on our other pages, not on this document.
Source: EWG Verified criteria for cleaning products (10.24), Environmental Working Group, 2024 Link to this fact
Hidden ingredients / Other evidence
EWG says a cleaning product's A-F grade is not an average of its ingredients' grades: it also counts how fully the maker discloses ingredients, any EWG-approved green certification, and the hazards of the formulation as a whole.
Moderate evidence: This is EWG describing its own method; the formula and weights are not given, and the 2012 method may have changed.
Source: Andrews, EWG, 2012 (web page) Link to this fact
Hidden ingredients / Other evidence
In EWG's cleaning-product grading, an ingredient with little or no public hazard information gets a C, and EWG says lack of safety data is the most common reason an ingredient gets a C.
Moderate evidence: A C therefore often means 'no public data', not 'found hazardous'. Self-described method; no ingredient counts given.
Source: Andrews, EWG, 2012 (web page) Link to this fact
Hidden ingredients / Other evidence
When only a chemical class (not the specific chemical) is known, EWG's cleaning-product method scores the ingredient as the most hazardous chemical in that class.
Moderate evidence: Self-reported rule; the article does not say how often it is applied.
Source: Andrews, EWG, 2012 (web page) Link to this fact
Hidden ingredients / Other evidence
Wet cleaning rests on water, but the detergents and spotting agents hold alcohol ethoxylates, glycol ethers, D-limonene, monoethanolamine, quaternary ammonia and trade secrets; many safety data sheets lacked ingredient data, some noted skin and eye irritation, and ethoxylated alcohols can carry 1,4-dioxane (county study pending).
Moderate evidence: From the county's review of a sample of safety data sheets, not testing of products or garments; the report still rated wet cleaning health-green.
Source: SCDHS 2018 Link to this fact
Hidden ingredients / Review of other studies
Galaxolide and Tonalide are used in perfumes, cleaning products, detergents and cosmetics, so they are typically covered by the single word 'fragrance' on a label.
Moderate evidence: Statement is in the paper's introduction and describes use, not what any given label discloses; this study measures no exposure.
Source: Schreurs 2005, Toxicological Sciences Link to this fact
Hidden ingredients / Other evidence
Limonene and beta-pinene scent terpenes were measurable in every perfume, deodorant and cleaning liquid tested (about 0.1-0.3% and 0.04-0.65% of product weight), even though labels only say 'fragrance' or, for the cleaners, name limonene.
Moderate evidence.
Caveats
Six products; GC-MS of three terpenes only, so other scent chemicals are unmeasured; alpha-pinene was below the detection range. The abstract's beta-pinene range (0.4-0.7%) differs from Table 1 (0.04-0.65%).
Information, not medical advice. See also: myths we won’t tell you.