References
Sources cited across all six volumes. Organised by volume and tiered by verification level — from primary regulatory text (Tier 1) to flagged tertiary sources (Tier 4) retained for completeness but explicitly named as below this project's standard.
Verification Tiers
- T1 Primary
- Regulatory text, government agency pages, legal documents fetched and read in full.
- T2 Peer-reviewed
- Published academic literature in named journals.
- T3 Reputable secondary
- Encyclopedias, major trade associations, official company histories, established science journalism.
- T4 Flagged / tertiary
- Commercial blogs, industry supplier content, hobbyist sites. Used but explicitly named as below this project's own standard.
Volume One — Facial Care
Volume One's references predate the per-claim citation discipline used in later volumes — they list general reference databases rather than tying each specific fact to its own source. That is an honest difference, not an error.
| Source | Tier | Covers |
|---|---|---|
| CosIng (European Commission) | T1 | Official EU cosmetic ingredient database: INCI names, functions, regulatory status |
| Regulation (EC) No 1223/2009 | T1 | EU Cosmetic Regulation — ingredient ordering, permitted preservatives |
| Commission Regulation (EU) 2024/996 | T1 | Current retinol concentration limits |
| 21 CFR Part 701 | T1 | US cosmetic labelling: descending order of predominance, 1% provision |
| COSMOS-standard | T1 | Organic/natural certification requirements |
| ECHA Substance Database | T1 | Chemical identity, classification, REACH status |
| PubChem / ChemSpider | T1 | Chemical structures, formulas, properties |
| CIR (Cosmetic Ingredient Review) | T2 | Published safety assessments |
| FDA Cosmetic Ingredient Database | T1 | US regulatory status and restrictions |
Volume Two — Makeup
| Source | Tier | Covers |
|---|---|---|
| 21 CFR § 74.2327 (Cornell LII / eCFR) | T1 | D&C Red No. 27 identity, uses, restrictions, 1982 approval |
| 21 CFR § 82.1327 | T1 | D&C Red No. 27 drug-use identity requirements |
| 21 CFR § 73.575 | T1 | Titanium dioxide color additive authorization |
| 21 CFR § 73.2250 (eCFR / Cornell LII) | T1 | Iron oxide identity and eye-area inclusion |
| 21 CFR § 701.13 | T1 | Net-quantity labelling by weight/volume |
| FDA, Sunscreen Drug Products for OTC Human Use | T1 | GRASE status for titanium dioxide and zinc oxide |
| FDA, Color Additives and Cosmetics: Fact Sheet | T1 | Eye-area listing requirement |
| FDA, Summary of Color Additives for Use in the US | T1 | Comparable eye-area colorant entries |
| FDA, published position on "cruelty-free" | T1 | Confirms no legal definition governs the term |
| Commission Regulation (EU) 2022/63; EFSA opinion (2021) | T1 | EU titanium dioxide food-additive withdrawal and rationale |
| European Commission, DG SANTE statement (2022) | T1 | Confirms TiO₂ ban's food-additive-only scope |
| Commission Regulation (EU) 2024/1328; REACH Annex XVII entry 70 | T1 | D4/D5 siloxane rinse-off restriction and 2026 extension |
| Regulation (EC) No 1223/2009 | T1 | EU compliance cost basis (Safety Report, Responsible Person) |
| COSMOS-standard | T1 | Silicone prohibition, mineral organic-percentage threshold |
| PubChem CID 83511 | T1 | D&C Red No. 27 formula and CAS number |
| CAS Reg. No. 1332-37-2; Color Index Nos. 77491/77492/77499 | T1 | Iron oxide chemical identity |
| CAS Registry No. 541-02-6 | T1 | Cyclopentasiloxane (D5) identity |
| US Patent 9,856,189; US Patent 5,888,485 | T1 | Beeswax composition, CAS number, melting point |
| Cosmetic Ingredient Review (CIR), via Cosmetics Info | T2 | "Cyclomethicone" as a mixture term (D4–D6) |
| Health Canada, Siloxane D5 info sheet (2012) | T1 | Canada's D5 assessment history and conclusion |
| Gobas et al., Environmental Toxicology and Chemistry (2015) | T2 | Independent fugacity analysis supporting D5's non-bioaccumulation |
| Baeyer, Berichte der deutschen chemischen Gesellschaft (1871) | T2 | Original fluorescein synthesis |
| Hektoen International, A Brief History of Fluorescein | T3 | Fluorescein's ophthalmic/hydrological/forensic uses |
| Springer, Titanium Dioxide Pigments; Works in Progress | T3 | Titanium discovery, 1916 pigment production, lead-carbonate replacement |
| Multiple corroborating pigment-history sources | T3 | Lead carbonate whitening history, 1930 lead-paint ban |
| Blombos Cave findings, published in Science | T2 | 100,000-year-old ochre-processing evidence |
| Multiple corroborating industrial-use sources | T4 | Jeweler's rouge composition, magnetite in recording media |
| Multiple corroborating archaeological/historical sources | T3 | Beeswax's Egyptian, Chinese, Greek/Roman history |
| Britannica, Carnauba Wax | T3 | Botanical source, growing region, industrial applications |
| CAMEO (Museum of Fine Arts, Boston) | T3 | Carnauba wax composition, melting point |
| New World Encyclopedia; Encyclopedia.com, Castor Oil | T3 | Egyptian tomb evidence, Ebers Papyrus reference |
| Engineering News; The Aerodrome Forum | T3 | Castor oil's WWI immiscibility mechanism |
| Fischer, Chemie in unserer Zeit (2009) | T2 | PVP's WWII plasma-substitute history |
| Schwarz, PVP: A Critical Review... | T2 | 1930s PVP development at I.G. Farben |
| ScienceDirect, PVP pharmaceutical excipient review | T2 | 1950s hairspray entry, K-value grading |
| BASF/BTC Europe, official company history | T3 | 1939 patent, monomer-vs-polymer distinction, Periston name |
Volume Three — Body Care
| Source | Tier | Covers |
|---|---|---|
| 21 CFR Part 350 | T1 | Antiperspirant OTC monograph, actives, concentration limits |
| 21 CFR 350.50 | T1 | Mandatory kidney-disease warning |
| 21 CFR 701.13 | T1 | Net-quantity labelling |
| NCATS Inxight Drugs, Aluminum Chlorohydrate record | T1 | OTC-approved status, 1903 Everdry date |
| US Patent 8,801,909 | T1 | Aluminum chlorohydrate empirical formula |
| Microbead-Free Waters Act of 2015 | T1 | Scope: rinse-off exfoliating products |
| Commission Regulation (EU) 2023/2055; REACH Annex XVII, Entry 78 | T1 | Microplastic definition, 2023–2035 phase-out |
| Freshfields; Care Europe | T3 | October 2025 compliance deadline confirmation |
| ScienceDirect, Theobroma Oil/Cocoa Butter | T2 | Polymorphism, melting range, stable beta-form |
| PMC (2021); PubMed, cocoa butter polymorphism studies | T2 | β2/βV crystal form, six polymorphic forms |
| Cornell University Library; Britannica, van Houten | T3 | 1828 hydraulic press, fat-reduction figure |
| Britannica, Soap and Detergent | T3 | WWI detergent development, whale-oil origin |
| Hendrikse, Bayly & Jimack (2022) | T2 | Ethoxylation's effect on SLES structure |
| Jayakumar & Micheletti, British Journal of Dermatology (2021) | T2 | Chesebrough's 1859 origin, whale-oil career shift |
| Wikipedia, Vaseline/Chesebrough Manufacturing | T4 | 1872 patent, corporate history |
| Science History Institute, WebElements, Chemicool, Jargonium, ScienceNordic (citing historian Helge Kragh) | T2 | 1825 anhydrous aluminum chloride prep, Wöhler's 1827 credit |
| Parchem, History of Sodium Bicarbonateflagged | T4 | Egyptian natron, Leblanc/Solvay process |
| Made How, How Baking Soda Is Madeflagged | T4 | Corroborates Leblanc-to-Solvay timeline |
| Sophim, 70 Years of Squalane Historyflagged | T4 | Tsujimoto's 1906 discovery |
| Typologyflagged | T4 | INCI labelling gap (animal/plant squalane) |
| bioRxiv preprint | T2 | Squalene vaccine-adjuvant use, CAS confirmation |
| Vanicream; antiperspirant-industry sources | T3 | "Clinical Strength" as undefined marketing language |
Volume Four — Hair Care
| Source | Tier | Covers |
|---|---|---|
| Britannica, Minoxidil | T3 | Upjohn's development, vasodilator discovery, approvals |
| US Patent Nos. 4,139,619, 4,596,812 | T1 | Topical hair-growth use as distinct patented application |
| Congressional Research Service (Congress.gov) | T1 | NDA pathway vs. ingredient-class monograph |
| HealthRX | T4 | Minoxidil patent/generic timeline |
| ScienceDirect Topics, Zinc Pyrithione | T2 | 1950s antimicrobial research, 1956 discovery |
| DrugBank, Pyrithione Zinc | T3 | Early-1960s FDA approval |
| Springer, zinc pyrithione antifouling biocide | T2 | Tributyltin ban, marine paint adoption |
| 21 CFR Part 358 Subpart H | T1 | Anti-dandruff OTC monograph |
| FDA, Hair Dyes consumer guidance | T1 | PPD sensitization, coal-tar caution requirement |
| CIR Safety Assessment of PPD (2023/2024) | T2 | Coal-tar exemption, eyelash restriction, US limits |
| News-Medical | T3 | EU SCCS 2% PPD restriction |
| Environmental Sciences Europe | T2 | 1863 PPD dye-synthesis date |
| ChemistryViews; Wikipedia | T3 | Perkin's 1856 mauveine discovery |
| Jacobs, Journal of Experimental Medicine (1916) | T2 | Bactericidal quaternary ammonium salts |
| Domagk, Deutsche Medizinische Wochenschrift (1935) | T2 | Long-chain-alkyl discovery |
| Industry database citing 2010 SCCS opinion | T3 | EU 2014 BTAC/CETAC restriction |
| US patent literature, dry shampoo compositions | T1 | Starch materials, modified starches |
| Unilever recall notice (FDA-published); Health Canada | T1 | Benzene-contamination recall |
| Burnett et al. (2021, peer-reviewed) | T2 | Keratin molecular weight range, source species |
| PMC/PubMed, feather keratin hydrolysates | T2 | Low-MW hydrolysates in hair conditioning |
| 21 CFR 701.13 | T1 | Net-quantity labelling |
Volume Five — Hand & Nail Care
| Source | Tier | Covers |
|---|---|---|
| PubChem CID 5634 | T1 | Undecylenic acid identity, 1877 isolation |
| Ross, Gebhart & Gerecht, JACS (1945) | T2 | Early polymer-chemistry interest |
| 21 CFR Part 333, Subpart C | T1 | OTC antifungal monograph |
| Del Rosso et al. (PMC) | T2 | Onychomycosis treatments are prescription-only |
| American Academy of Dermatology | T3 | OTC antifungal cannot treat nail fungus |
| Practical Dermatology | T3 | Nitrocellulose's automotive origin, Revlon founding |
| American Coatings Association | T3 | DuPont Duco development, GM adoption |
| FDA, Nail Care Products | T1 | No formal MMA ban; formaldehyde mechanism |
| California DTSC; Arizona Barbering Board | T1 | State-level MMA regulation, 2024–2025 rulemaking |
| ECHA, REACH Annex XVII; CLH documentation | T1 | No EU restriction on MMA/EMA; hazard classification |
| CIR Expert Panel, Int'l Journal of Toxicology (2005, fetched in full) | T2 | 1974 "Long Nails" injunction; 1999 EMA assessment |
| Chemistry World; McGill; Microbiology Society | T2 | 1915 Weizmann fermentation, WWI acetone crisis |
| Britannica; Hektoen International; EBSCO | T2 | Wöhler's aluminum/urea work, vitalism correction |
| SCCS/1538/14 | T1 | Formaldehyde nail-hardener limit reduction |
| Lazzarini et al. (2024); Sainio et al. (1997) | T2 | TSFR's 1939 entry, patch-test data |
| Evans & Bishop (1922, via PMC); UpToDate; JAMA | T2 | Vitamin E discovery, tocopherol etymology |
| Wikipedia, Ducoflagged | T4 | Cross-industry uses (Duco Cement, Fender guitars) |
| NailKnowledgeflagged | T4 | Timeline corroboration |
Volume Six — Hygiene & Cleansing
| Source | Tier | Covers |
|---|---|---|
| 21 CFR § 701.20 (Cornell LII) | T1 | True soap's exact two-part legal test |
| CPSC.gov | T1 | CPSC/FDA split, 2022 MoCRA effect |
| STENDERS Cosmetics; Auctores | T3 | Saponification, Chevreul's 1823 formalization |
| Singapore Soap Supplies; soaphistory.net; HLS Linen Servicesflagged | T4 | ~2800 BC Babylonian origin, ~2200 BC clay tablet recipe |
| Federal Register (2016) | T1 | GRAS/GRAE finding, 19 named ingredients |
| Halden et al., Florence Statement (PMC) | T2 | EU 2016 decision, Minnesota ban |
| eosCUflagged | T4 | Triclosan's 1970s hospital-scrub origin |
| GOJO Industries; Forbes | T3 | 1946 founding, 1988/1997 Purell history |
| FDA, Import Alert 62-08 | T1 | Methanol death/poisoning counts |
| Yip et al., CDC MMWR (2020) | T2 | Methanol vs. ethanol poisoning distinction |
| 21 CFR § 740.12 (eCFR) | T1 | Feminine deodorant spray definition, "hygiene" prohibition |
| FDA 510(k) letters K152168, K221243, K202017 | T1 | 21 CFR § 884.5300, "Condom" classification |
Still Open
Five specific items remain flagged across all six volumes. None blocks any core teaching point — in each case the material is uncontroversial and independently corroborated. They are tracked here so "still open" means something specific and actionable, not a general hedge.
| Volume | Material | What is flagged | Severity |
|---|---|---|---|
| Three | Sodium Bicarbonate | Historical section (Leblanc 1791, Solvay 1860s, Church & Dwight 1846) rests on Parchem and Made How — no peer-reviewed or primary anchor | Low |
| Three | Squalane | 1906 discovery and INCI-labelling-gap claims rest on manufacturer content and a brand blog, with one bioRxiv preprint as the strongest anchor | Low |
| Five | Nitrocellulose | Peripheral details only (Duco Cement, Fender Telecaster facts via Wikipedia; timeline via NailKnowledge) — core DuPont/Revlon claim is solidly sourced | Very low |
| Six | True Soap | Ancient-history section (~2800 BC Babylon, ~2200 BC clay tablet) rests on a soap supplier, a hobbyist history site, and a linen-services company blog | Low |
| Six | Triclosan | 1970s hospital-scrub origin traces to a single blog (eosCU) — the regulatory core of the same profile is excellently sourced and unaffected | Low |