Find products and ingredients Learn how Skin Deep® works Meet our experts Discover EWG VERIFIED®

Understanding Skin Deep® ratings

Every product and ingredient in Skin Deep® gets a two-part score – one for hazard and one for data availability.

Hazard Score


Hazards score scale
Hazards score scale
Hazards score scale


The Skin Deep ingredient hazard score, from 1 to 10, reflects known and suspected hazards linked to the ingredients.

Hazards linked to ingredients

A product’s hazard score is not an average of the ingredients’ hazard scores. It is calculated using a weight-of-evidence approach that factors in all of the hazards or health impacts associated with the ingredients. To see details of how our hazard scores are calculated, see the “Hazard Ratings” section of our methodology.

Data Availability

Least Data

Hazards score scale
Hazards score scale
Hazards score scale

Most Data

The Skin Deep data availability rating reflects the number of scientific studies about the product or ingredient in the published scientific literature. Not all ingredients are equal when it comes to safety data. Some have been studied extensively. For others there is only a modest volume of research, and still others have not been assessed at all. The data availability rating indicates the scope of data on which EWG has based an ingredient and/or product score.

Overall Product Score

To calculate a product score, we review individual ingredient hazards and evaluate each product in relation to the rest of the products in the Skin Deep database. The safest products score well by both measures, with a low hazard rating and a fair or better data availability rating.

What does the EWG VERIFIED® mark mean?

The EWG VERIFIED® mark on a product indicates that the product meets EWG’s strictest standards for transparency and health.

checkmark Avoids EWG's Ingredients of concern

EWG VERIFIED products cannot contain any ingredients on EWG’s “Unacceptable” list, which includes ingredients with health, ecotoxicity and/or contamination concerns.

checkmark Full transparency

EWG VERIFIED products must meet EWG’s standards for ingredient disclosure on the label; products with the VERIFIED mark are made by manufacturers that have been fully transparent with EWG about that product’s ingredients, including fragrance ingredients.

checkmark Good manufacturing practices

EWG VERIFIED product manufacturers must develop and follow current good manufacturing practices to further ensure the safety of their products.

Ingredient Concerns

Cancer: Ingredients linked to cancer in government, industry or academic studies or assessments.

Developmental and reproductive toxicity: Ingredients linked to developmental and reproductive toxicity, a broad class of health effects that range from infertility and reproductive organ cancers to birth defects and developmental delays in children.

Allergies and immunotoxicity: Ingredients linked to harm to the immune system, a class of health problems that manifest as allergic reactions or an impaired capacity to fight disease and repair damaged tissue in the body.

Use restrictions: Ingredients restricted or prohibited for use in cosmetics, according to industry safety guidelines, government requirements or guidance from the U.S., EU, Japan or Canada.

Endocrine disruption: Ingredients may affect the proper functioning of the body's hormone system.

Neurotoxicity: Ingredients linked to harm to the brain and nervous system, a class of health problems that can range from subtle developmental delays to chronic nerve degeneration diseases.

Organ system toxicity: Ingredients linked to toxicity of one or more biological systems in the body, for instance, cardiovascular, stomach and digestive track, or respiratory system, through laboratory studies or studies of people.

Biochemical or cellular level changes: Ingredients affect the body at a cellular or biochemical level, potentially leading to larger but poorly understood health implications.

Persistence and bioaccumulation: Ingredients resist normal breakdown in the environment; build up in wildlife, the food chain, and people; and linger in the body for years or even decades after exposure.

Ecotoxicity: Ingredients linked to toxicity of wildlife that may include fish, plants or other wild organisms.

Irritation: Ingredients linked to irritation of the skin, eyes or lungs.

Occupational hazards: Ingredients linked to hazards for workers exposed on the job, including immediate dangers from chemical handling, or longer-term health effects from routine occupational exposures.

Enhanced skin absorption: Ingredients may more readily absorb through the skin due to properties like penetration-enhancing abilities or small particle size, or by virtue of where they are applied on the body (on infant skin, or on lips or damaged skin).

Contamination concerns: Ingredients may be contaminated with toxic impurities, many of which are linked to cancer, according to government and cosmetic industry ingredient safety assessments or peer-reviewed studies.

Skindeep Healthy Living App

Discover a curated selection of healthier beauty and personal care products. Donate today to get your EWG VERIFIED® holiday gift set!