Ingredient safety register
71 substances we flag, each with the authority behind the concern, its regulatory position where one exists, and how often it actually appears across the products we have analysed. 48 of them are present in the catalogue today.
Avoid
13 substances
Peanuts
Major allergen — can cause life-threatening anaphylaxis
Sodium Nitrate
Preservative — converts to nitrite; probable carcinogen
Methylisothiazolinone
Preservative — potent contact sensitiser; banned from EU leave-on products
Erythrosine
Synthetic red dye — US FDA revoked its food authorisation in 2025 after cancer in male rats; still permitted in India
Coal Tar
Dandruff/psoriasis treatment — known carcinogen (IARC Group 1)
Partially Hydrogenated Oil
Partially hydrogenated oil — industrial trans fat, harmful to heart health
Dibutyl Phthalate
Plasticiser — reproductive toxicant; banned in EU cosmetics
Lead
Heavy metal — neurotoxin with no safe exposure level
Sodium Nitrite
Curing agent — classified probable carcinogen (IARC Group 2A)
Potassium Bromate
Flour improver — carcinogen; banned in India & EU
Mercury
Heavy metal — neurotoxin; mercury-added cosmetics phased out under the Minamata Convention
Brominated Vegetable Oil
Citrus-drink emulsifier — bromine accumulates in body fat; authorisation revoked in the US
Formaldehyde
Preservative — known carcinogen (IARC Group 1)
Limit
44 substances
Palm Oil
High in saturated fat — cardiovascular concern with regular high intake
Disodium Ribonucleotides
Flavour enhancer — a purine source; relevant for people managing gout
Hydrogenated Vegetable Fat
Hydrogenated vegetable fat — high saturated fat source
Fruit Juice Concentrate
Concentrated fruit-juice sweetener — a free-sugar source, often used to sweeten "no added sugar" products
Titanium Dioxide
Whitening agent — banned as food additive in EU (2022); potential genotoxin
Sodium Lauryl Sulfate
Surfactant — strong skin and mucous membrane irritant
Caramel Colour (Class III & IV)
Ammonia-process caramel colour (INS 150c/150d) — can generate 4-MEI, an IARC Group 2B classification
Interesterified Vegetable Fat
Modified vegetable fat — high in saturated fat, but not a trans-fat source
Tartrazine
Artificial colour — linked to hyperactivity in children; aspirin-sensitive people may react
Disodium Inosinate
Purine-based flavour enhancer — gout risk
Disodium Guanylate
Purine-based flavour enhancer — gout risk
BHT
Synthetic antioxidant — endocrine-disruption concern (NOT an IARC carcinogen; that is BHA)
Talc
Cosmetic powder — potential asbestos contamination; ovarian cancer concern
Sunset Yellow FCF
Artificial colour — hyperactivity concern in children
TBHQ
Synthetic antioxidant — high doses linked to tumours in animals
Sodium Triphosphate
Phosphate additive — concern for kidney & heart health
DMDM Hydantoin
Formaldehyde-releasing preservative — carcinogen concern
Margarine
Hardened vegetable fat spread — high in saturated fat
High Fructose Corn Syrup
Refined sweetener — linked to obesity, fatty liver, insulin resistance
Triclosan
Antibacterial — endocrine disruptor; banned in US OTC soaps
Sulphur Dioxide
Preservative — triggers asthma and allergic reactions in sensitive people
Climbazole
Anti-dandruff antifungal — concentration restricted in EU cosmetics
CI 47000
Synthetic quinoline dye — recognised contact sensitiser; restricted in cosmetics
Sodium Polyphosphate
Phosphate additive — concern for kidney & heart health
BHA
Synthetic antioxidant — possible carcinogen (IARC Group 2B)
Carbon Black
Pigment — IARC Group 2B possible carcinogen; no skin benefit
Toluene
Solvent in nail products — neurotoxin; avoid during pregnancy
Sodium Dodecylbenzene Sulfonate
Detergent surfactant — a laundry-grade cleanser, harsh on skin
Ammonium Lauryl Sulfate
Harsh primary surfactant — strips the skin barrier, like SLS
Diethyl Phthalate
Fragrance carrier — endocrine disruption concern
Oxybenzone
Sunscreen UV filter — endocrine disruptor; banned in Hawaii (coral reef damage)
Homosalate
UV filter — EU restricted to 7.34% over endocrine concerns
Triclocarban
Antibacterial — endocrine concerns; banned from US wash-off products
Cyclomethicone
Silicone — D4 & D5 banned in EU wash-off cosmetics; endocrine concern
Ethylhexyl Methoxycinnamate
UV filter — hormone-disruption concern; EU capped at 10% after review
Methylparaben
Paraben preservative — suspected endocrine disruptor
Resorcinol
Hair dye component — thyroid disruptor; restricted in EU
Aspartame
Artificial sweetener — contraindicated in phenylketonuria (PKU)
Hydroquinone
Skin lightener — banned in EU cosmetics; potential carcinogen
Imidazolidinyl Urea
Formaldehyde-releasing preservative — allergy and carcinogen risk
Butylparaben
Paraben preservative — strongest endocrine disruption among common parabens
4-Methylbenzylidene Camphor
UV filter — banned in the EU (2025) over thyroid/oestrogenic activity; not permitted in the US
Benzisothiazolinone
Preservative — contact sensitiser; not permitted in EU cosmetics
Propylparaben
Paraben preservative — endocrine disruption concern
Caution
13 substances
Fragrance
Undisclosed fragrance mix — common allergen; 3,000+ possible chemicals
Sodium Carbonate
Sodium source — adds to overall sodium load in diet
Fractionated Fat
Industrially modified fat — the label does not say which fraction, or from which oil
Sodium Laureth Sulfate
Surfactant — can irritate sensitive skin; may carry a 1,4-dioxane impurity
Brilliant Blue
Synthetic blue dye — banned in several countries
Sodium C14-16 Olefin Sulfonate
Anionic surfactant — high-foaming and drying; harshness depends on what it is blended with
Carrageenan
Thickener — linked to gut inflammation in some studies
Camphor
Can cause seizures if swallowed in quantity — supervise young children
Dipotassium Phosphate
Phosphate & potassium additive — caution for kidney patients
Potassium Carbonate
Potassium additive — caution for kidney patients (hyperkalaemia risk)
Sodium Coco-Sulfate
Harsh surfactant — chemically an SLS blend, despite the natural-sounding name
Monosodium Glutamate
MSG — may cause sensitivity reactions in some people
Aluminium
Antiperspirant ingredient — ongoing debate over breast cancer/Alzheimer's link
Note
1 substance
Each entry states the authority it rests on. Prevalence is measured across the products Decode Label has analysed, not the market as a whole, and presence on a label is not a statement about dose. No brand can pay to add, remove or soften an entry.