Five principles sit under every verdict on this site. They are load-bearing: change one and the whole directory has to be re-examined.
An ingredient's safety depends on the concentration and the product type it shows up in. Salicylic acid at 0.5% in a leave-on moisturizer and 2% in a rinse-off cleanser are not the same thing — and a tool that rates them identically is lying to you. Our ingredient packets carry the dose math; Phase 2 will apply it to finished formulas.
We publish the parent company behind every brand we rate. We don't accept paid verification, seals, or tiered listings. When an authority we cite has a disclosed industry relationship (a CIR panelist consults for a supplier), we say so next to the citation.
1,4-dioxane, NDELA, heavy-metal residues and similar process byproducts are not the ingredient itself, but they're what the ingredient can ship with. We list them separately, labeled as manufacturing notes — not alarmist, but not hidden.
A product that grows mold is not a safe product. We rate preservatives on whether they work at the pH and concentration they're used at, and we don't dock points for the mere presence of a preservative — only for unresolved toxicology.
Every page carries the date it was last verified and a re-review cadence. When a new CIR opinion, SCCS reassessment, or peer-reviewed paper changes the picture, we rewrite the packet — and we keep the previous version's hash visible.
If we make a claim and can't produce the excerpt, the page doesn't publish. If a source gets retracted, the packet gets a public errata note, not a silent edit.
Has the ingredient been reviewed by at least one of: CIR, SCCS, CosIng, FDA, or a peer-reviewed safety assessment? If not, tier is Insufficient data.
Take the most authoritative explicit verdict available. Regulatory opinions outrank individual papers. CIR outranks a single PubMed entry.
If the verdict carries a concentration ceiling, compare to typical in-use concentrations for the product classes where it appears. If typical usage is under the ceiling, Safe; if it routinely exceeds, Safe with conditions.
Flag any documented manufacturing byproducts (1,4-dioxane, NDELA, etc.) and list separately. Does not change the tier — changes what the consumer should check on the product.
Packet is stamped with today's date. Re-review when a new CIR / SCCS opinion publishes or on trigger events.