Beauty regulation in the United States has not been meaningfully updated since 1938. The label on your shampoo is often the only information you get — and most of it is written in a language called INCI that shoppers were never taught to read. Here is the short course.
INCI stands for International Nomenclature of Cosmetic Ingredients. It is the global standard adopted by the FDA, EU, and most of Asia so that the same ingredient is listed the same way everywhere. INCI names are often Latinised or chemical — "Butyrospermum Parkii Butter" is shea butter, "Tocopherol" is vitamin E, "Aqua" is water.
Two rules make INCI readable: ingredients above 1% concentration are listed in descending order of weight, and ingredients below 1% can be listed in any order at the end. That end-of-list zone is where preservatives, fragrance, and colour additives live. Those are the ingredients that deliver most of the irritation and endocrine-disruption risk, even at tiny concentrations.
Parabens (methylparaben, propylparaben, butylparaben, ethylparaben, isopropylparaben, isobutylparaben) are broad-spectrum antimicrobial preservatives that have been used in cosmetics since the 1920s. The concern is weak estrogenic activity — they bind and activate the estrogen receptor at roughly 10,000× lower potency than estradiol, but they also concentrate in breast tissue and have been detected in tumour biopsies (Darbre 2004 onwards). The EU has banned five of them in leave-on products. The FDA has not.
Methylparaben and ethylparaben are the lower-concern members and still common. Butyl-, isobutyl-, and propylparaben are the ones a cautious reader should avoid in anything that stays on the skin. Look for them in the last third of the ingredient list.
Sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES) are the foaming surfactants in most drugstore shampoos, body washes, and toothpastes. Their problem is not toxicity — it is that they strip the skin and scalp lipid barrier and trigger contact dermatitis in sensitive users. SLES has a minor secondary concern: its manufacturing process can leave residual 1,4-dioxane, a probable human carcinogen, unless the manufacturer vacuum-strips the final product. Reputable brands now do; bargain brands often do not.
The useful swap is to look for coco-glucoside, decyl-glucoside, coco-betaine, or sodium cocoyl isethionate. All clean well and do not strip the barrier.
This is the single biggest gap in US cosmetic labelling. The word "Fragrance" (or "Parfum," or "Aroma") on an ingredient list is a legal trade-secret placeholder. A single "Fragrance" entry can represent anywhere from three to several hundred individual chemicals, including phthalates (diethyl phthalate, DEP), musks, allergens, and solvents — none of which have to be disclosed.
Phthalates are the specific concern: they are endocrine disruptors, they cross the placenta, and US biomonitoring data (NHANES) still find them in the majority of reproductive-age women. The EU requires 26 specific fragrance allergens to be listed by name once they exceed a threshold. The US requires none of them.
The practical rule: if you are pregnant, trying to become pregnant, or using a product on a child, look for "Fragrance-Free" (not "Unscented" — unscented products often add masking fragrances). For everyone else, treat "Fragrance" as an unknown and prefer products that either omit it or disclose specific essential oils by name.
The Environmental Working Group's Skin Deep database scores individual cosmetic ingredients on a 1 to 10 hazard scale: 1 to 2 is low, 3 to 6 is moderate, 7 to 10 is high. The scoring combines published toxicology, endocrine-disruption signals, carcinogenicity data, and data-gap penalties. It is not perfect — the data-gap penalty can over-rate obscure-but-safe ingredients — but it is the best publicly available tool for quickly triaging an unfamiliar INCI list. Our beauty scoring engine uses EWG scores as one of five inputs.
The "EWG Verified" mark (distinct from the hazard scale) is a stricter certification — no ingredient above EWG 2, full fragrance disclosure, and manufacturing-process transparency. When you see it on a product, the label has already been vetted for you.
The EU prohibits over 1,600 ingredients in cosmetics. The FDA prohibits 11. The practical gap list — ingredients you will still find in US beauty products that are banned or severely restricted in Europe — includes formaldehyde and formaldehyde-releasing preservatives (DMDM hydantoin, quaternium-15, imidazolidinyl urea), coal-tar colours, certain parabens (butyl, propyl, isobutyl, isopropyl in leave-on products), triclosan (also now FDA-banned in soaps but still allowed in toothpaste), and lead acetate in hair dye.
A quick heuristic: if you cannot pronounce it and it ends in "-paraben," "-quaternium," or "-urea," or if it includes "formaldehyde" anywhere, put the bottle back.
First three ingredients: water, the primary emollient or surfactant, the primary active. If these are clean, most of the product is clean. Last third of the list: preservatives, fragrance, colourants. This is where you will find the problems. A clean leave-on product should have phenoxyethanol or a naturally-derived preservative at the end, no "Fragrance" entry, and ideally an EWG Verified or MADE SAFE seal on the front.
The app runs this scan in under a second. Point your camera at any beauty product — What's the Score? cross-references every INCI name against the EU banned list, the EWG hazard scale, and our physician-curated concern database.