Before acting on an EWG score, it helps to understand where the number comes from. The database can be a useful starting point for ingredient research, but it has limitations that matter in practice.
What EWG is
EWG (Environmental Working Group) is a US-based non-profit organization. It is not a government regulatory body and does not hold legal authority like the FDA, Korea's KFDA (Ministry of Food and Drug Safety), or EU regulatory agencies. EWG runs its own Skin Deep cosmetic ingredient database and assigns each ingredient a score from 1 to 10, where 1–2 indicates low concern, 3–6 moderate concern, and 7–10 high concern.
The database is widely used as a consumer reference tool. But the way its scores are calculated has several characteristics that can lead to misinterpretation if you take the number at face value.
How the scores are calculated
EWG reviews each ingredient against a range of concerns including potential carcinogenicity, developmental and reproductive toxicity, allergic reactions, and skin irritation. It also factors in how much published safety data is available for that ingredient. Two concepts are central to making sense of the scores.
The difference between hazard and risk
Hazard refers to an intrinsic property of a substance: its potential to cause harm at high concentrations or under specific conditions. Risk accounts for actual use: how much of the ingredient is in the product, how often it contacts skin, and by what route. An ingredient that causes toxicity in laboratory studies at high doses may be entirely unremarkable at the trace concentrations found in a face cream.
Korea's KFDA and the EU's Scientific Committee on Consumer Safety (SCCS) both base their evaluations on risk. They consider the actual concentration permitted in cosmetics and the realistic level of exposure. EWG scores do not always incorporate this same context, which is why a score and a regulatory assessment can point in different directions for the same ingredient.
How data gaps push scores up
When EWG's database lacks sufficient safety research on an ingredient, it applies a data gap penalty, raising the score to signal uncertainty. The result is that an ingredient backed by decades of safety data can score better than a less-studied plant extract, regardless of their actual risk. A high score due to a data gap is not the same as evidence of harm.
Common misconceptions
| Misconception | Reality |
|---|---|
| EWG score 7 or higher means the ingredient is dangerous and should be avoided | Ingredients permitted within safe concentration limits by KFDA or EU SCCS can still carry high EWG scores. Check regulatory limits alongside the EWG rating rather than using the score alone |
| EWG score 1 or 2 means the ingredient is safe for everyone | A low score means no major concern was found in available data. It does not account for individual allergies or sensitivities, which vary from person to person |
| EWG is an official regulatory standard | EWG is a US non-profit without regulatory authority. Its methodology is not independently peer-reviewed in the same way as KFDA or EU SCCS evaluations |
| Natural ingredients always score low while synthetic ones score high | Some natural-derived ingredients score high when high-dose toxicity data exists for them; some synthetic ingredients score low when extensive safety evidence is on record |
How EWG compares to KFDA and EU SCCS
Korea's KFDA sets permitted ingredients, use limits, and restricted conditions through its "Standards for the Safety of Cosmetics" regulation. The EU does the same under Regulation (EC) No 1223/2009 with supporting SCCS opinions. Both evaluate safety based on realistic cosmetic concentrations and typical exposure patterns.
If an ingredient passes KFDA or EU SCCS review at a specified concentration, using a product formulated to that standard falls within a legally and scientifically assessed range of safety, regardless of its EWG score. The reverse also holds: a low EWG score is not a substitute for a personal patch test, especially if you have a known skin sensitivity.
How to use EWG effectively
- Use it as a starting point, not a verdict. EWG is a reasonable first stop for learning about an ingredient. Do not stop there. Cross-check with regulatory databases and the actual product concentration.
- Check KFDA or EU regulatory limits alongside the score. Korea's KFDA ingredient portal and the EU's CosIng database both show permitted concentrations and any restrictions for individual ingredients.
- Look at which concern is driving the score. EWG displays the breakdown behind each score. A score elevated mainly by a data gap means something different than one driven by documented toxicity findings.
- Patch-test new products regardless of scores. No rating system predicts individual allergic responses. Apply a small amount to the inner forearm or behind the ear and observe for 24 hours before full use.
